Brazilian Journal of Cardiovascular Surgery 27.2 - 2012

Page 1

27.2 APRIL/JUNE 2012

AR SURGERY ARDIO REVIST A BRASILEIRA DE CIRURGIA C ARDIO VASCUL AR/ BRAZILIAN JOURNAL OF C ASCULAR ARDIOV CARDIO REVISTA CARDIO ARDIOV ASCULAR/ VASCUL V OL. 27 Nยบ 2 APRIL/JUNE 2012 VOL.


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RBCCV

EDITOR/EDITOR Prof. Dr. Domingo M. Braile - PhD

REVIST A BRASILEIRA DE REVISTA CIRURGIA C A RDIO VASCUL AR CA RDIOV BRAZILIAN JOURNAL OF CARDIOVASCULAR SURGERY

São José do Rio Preto - SP - Brasil domingo@braile.com.br EDITORES ANTERIORES/FORMER EDITORS • Prof. Dr. Adib D. Jatene PhD - São Paulo (BRA) [1986-1996] • Prof. Dr. Fábio B. Jatene PhD - São Paulo (BRA) [1996-2002]

ASSESSORA EDITORIAL/EDITORIAL ASSISTANT Rosangela Monteiro PhD - São Paulo (BRA) rosangela.monteiro@incor.usp.br

EDITOR EXECUTIVO EXECUTIVE EDITOR Ricardo Brandau Pós-graduado em Jornalismo Científico - S. José do Rio Preto (BRA) brandau@sbccv.org.br

EDITORES ASSOCIADOS/ASSOCIATE EDITORS • • • • • • •

Antônio Sérgio Martins Gilberto Venossi Barbosa José Dario Frota Filho José Teles de Mendonça Luciano Cabral Albuquerque Luis Alberto Oliveira Dallan Luiz Felipe Pinho Moreira

Botucatu (BRA) Porto Alegre (BRA) Porto Alegre (BRA) Aracaju (BRA) Porto Alegre (BRA) São Paulo (BRA) São Paulo (BRA)

• • • • • • •

Manuel Antunes Mario Osvaldo P. Vrandecic Michel Pompeu B. Oliveira Sá Paulo Roberto Slud Brofman Ricardo C. Lima Ulisses A. Croti Walter José Gomes

Coimbra (POR) Belo Horizonte (BRA) Recife (BRA) Curitiba (BRA) Recife (BRA) S.J. Rio Preto (BRA) São Paulo (BRA)

EDITOR DE ESTATÍSTICA/STATISTICS EDITOR • Orlando Petrucci Jr.

Campinas (BRA)

CONSELHO EDITORIAL/EDITORIAL BOARD • Adib D. Jatene • Adolfo Leirner • Adolfo Saadia • Alan Menkis • Alexandre V. Brick • Antônio Carlos G. Penna Jr. • Bayard Gontijo Filho • Borut Gersak • Carlos Roberto Moraes • Christian Schreiber • Cláudio Azevedo Salles • Djair Brindeiro Filho • Eduardo Keller Saadi • Eduardo Sérgio Bastos • Enio Buffolo • Fábio B. Jatene • Fernando Antônio Lucchese • Gianni D. Angelini • Gilles D. Dreyfus • Ivo A. Nesralla • Jarbas J. Dinkhuysen • José Antônio F. Ramires • José Ernesto Succi • José Pedro da Silva • Joseph A. Dearani

São Paulo (BRA) São Paulo (BRA) Buenos Aires (ARG) Winnipeg (CAN) Brasília (BRA) Marília (BRA) Belo Horizonte (BRA) Ljubljana (SLO) Recife (BRA) Munique (GER) Belo Horizonte (BRA) Recife (BRA) Porto Alegre (BRA) Rio de Janeiro (BRA) São Paulo (BRA) São Paulo (BRA) Porto Alegre (BRA) Bristol (UK) Harefield (UK) Porto Alegre (BRA) São Paulo (BRA) São Paulo (BRA) São Paulo (BRA) São Paulo (BRA) Rochester (USA)

VERSÃO PARA O INGLÊS/ENGLISH VERSION • Alexandre Werneck • Fernando Pires Buosi • Marcelo Almeida • Pablo Sebastian Maluf

• • • • • • • • • • • • • • • • • • • • • • • •

Joseph S. Coselli Luiz Carlos Bento de Souza Luiz Fernando Kubrusly Mauro Paes Leme de Sá Miguel Barbero Marcial Milton Ary Meier Nilzo A. Mendes Ribeiro Noedir A. G. Stolf Olivio Souza Neto Otoni Moreira Gomes Pablo M. A. Pomerantzeff Paulo Manuel Pêgo Fernandes Paulo P. Paulista Paulo Roberto B. Évora Pirooz Eghtesady Protásio Lemos da Luz Reinaldo Wilson Vieira Renato Abdala Karam Kalil Renato Samy Assad Roberto Costa Rodolfo Neirotti Rui M. S. Almeida Sérgio Almeida de Oliveira Tomas A. Salerno

Houston (USA) São Paulo (BRA) Curitiba (BRA) Rio de Janeiro (BRA) São Paulo (BRA) Rio de Janeiro (BRA) Salvador (BRA) São Paulo (BRA) Rio de Janeiro (BRA) Belo Horizonte (BRA) São Paulo (BRA) São Paulo (BRA) São Paulo (BRA) Ribeirão Preto (BRA) Cincinatti (USA) São Paulo (BRA) Campinas (BRA) Porto Alegre (BRA) São Paulo (BRA) São Paulo (BRA) Cambridge (USA) Cascavel (BRA) São Paulo (BRA) Miami (USA)

ÓRGÃO OFICIAL DA SOCIEDADE BRASILEIRA DE CIRURGIA CARDIOVASCULAR DESDE 1986 OFFICIAL ORGAN OF THE BRAZILIAN SOCIETY OF CARDIOVASCULAR SURGERY SINCE 1986


ENDEREÇO/ADDRESS

Sociedade Brasileira de Cirurgia Cardiovascular Rua Beira Rio, 45 • 7º andar - Cj. 72 • Vila Olímpia • Fone: 11 3849-0341. Fax: 11 5096-0079. Cep: 04548-050 • São Paulo, SP, Brasil E-mail RBCCV: revista@sbccv.org.br • E-mail SBCCV: sbccv@sbccv.org.br • Site SBCCV: www.sbccv.org.br • Sites RBCCV: www.scielo.br/rbccv / www.rbccv.org.br (também para submissão de artigos)

Publicação trimestral/Quarterly publication Edição Impressa - Tiragem: 200 exemplares (*)

REVISTA BRASILEIRA DE CIRURGIA CARDIOVASCULAR (Sociedade Brasileira de Cirurgia Cardiovascular) São Paulo, SP - Brasil. v. 119861986, 1: 1,2 1987, 2: 1,2,3 1988, 3: 1,2,3 1989, 4: 1,2,3 1990, 5: 1,2,3 1991, 6: 1,2,3 1992, 7: 1,2,3,4 1993, 8: 1,2,3,4 1994, 9: 1,2,3,4

1995, 10: 1,2,3,4 1996, 11: 1,2,3,4 1997, 12: 1,2,3,4 1998, 13: 1,2,3,4 1999, 14: 1,2,3,4 2000, 15: 1,2,3,4 2001, 16: 1,2,3,4 2002, 17: 1,2,3,4 2003, 18: 1,2,3,4

2004, 19: 1,2,3,4 2005, 20: 1,2,3,4 2006, 21: 1 [supl] 2006, 21: 1,2,3,4 2007, 22: 1 [supl] 2007, 22: 1,2,3,4 2008, 23: 1 [supl] 2008, 23: 1,2,3,4 2009, 24: 1 [supl]

2009, 24: 1,2,3,4 2009, 24: 2 [supl] 2010, 25: 1,2,3,4 2010, 25: 1 [supl] 2011, 26: 1,2,3,4 2011, 26: 1 [supl] 2012, 27: 1,2 2012, 27: 1 [supl]

ISSN 1678-9741 - Publicação online ISSN 0102-7638 - Publicação impressa RBCCV 44205

CDD 617.4105 NLM18 WG 168

(*) ASSOCIAÇÃO PAULISTA DE BIBLIOTECÁRIOS. Grupo de Bibliotecários Biomédicos. Normas para catalogação de publicações seriadas nas bibliotecas especializadas. São Paulo, Ed. Polígono, 1972

INDEXADA EM • Thomson Scientific (ISI) http://science.thomsonreuters.com • PubMed/Medline www.ncbi.nlm.nih.gov/sites/entrez

• ADSAUDE - Sistema Especializado de Informação em Administração de Saúde www.bibcir.fsp.usp.br/html/p/ pesquisa_em_bases_de_dados/ programa_rede_adsaude

• SciELO - Scientific Library Online www.scielo.br

• Index Copernicus www.indexcopernicus.com

• Scopus www.info.scopus.com

• Google scholar http://scholar.google.com.br/scholar

• LILACS - Literatura Latino-Americana e do Caribe em Ciências da Saúde. www.bireme.org • LATINDEX -Sistema Regional de Información en Línea para Revistas Cientificas de America Latina, el Caribe, España y Portugal www.latindex.uam.mx

Distribuída gratuitamente a todos os sócios da Sociedade Brasileira de Cirurgia Cardiovascular


SOCIEDADE BRASILEIRA DE CIRURGIA CARDIOVASCULAR BRAZILIAN SOCIETY OF CARDIOVASCULAR SURGERY DEPARTAMENTO DE CIRURGIA DA SOCIEDADE BRASILEIRA DE CARDIOLOGIA DEPARTMENT OF SURGERY OF THE BRAZILIAN SOCIETY OF CARDIOLOGY

“Valorizando o profissional em prol do paciente” DIRETORIA 2011 - 2013 Presidente: Vice-Presidente: Secretário Geral: Tesoureiro: Diretor Científico:

Walter José Gomes (SP) João Alberto Roso (RS) Marcelo Matos Cascudo (RN) Eduardo Augusto Victor Rocha (MG) Fábio Biscegli Jatene (SP)

Conselho Deliberativo:

Bruno Botelho Pinheiro (GO) Henrique Barsanulfo Furtado (TO) José Glauco Lobo Filho (CE) Rui M.S. Almeida (PR) Henrique Murad (RJ)

Editor da Revista: Editor do Site: Editores do Jornal:

Domingo Marcolino Braile (SP) Vinicius José da Silva Nina (MA) Walter José Gomes (SP) Fabricio Gaburro Teixeira (ES) Josalmir José Melo do Amaral (RN) Luciana da Fonseca (SP)

Presidentes das Regionais Afiliadas Norte-nordeste: Rio de Janeiro: São Paulo: Minas Gerais: Centro-Oeste: Rio Grande do Sul: Paraná: Santa Catarina:

Maurílio Onofre Deininger (PB) Marcelo Sávio da Silva Martins Carlos Manuel de Almeida Brandão AntonioAugusto Miana Luiz Carlos Schimin (DF) Marcela da Cunha Sales Rodrigo Mussi Milani Lourival Bonatelli Filho

Departamentos DCCVPED: DECAM: DECA: DECEN: DEPEX: DECARDIO:

Marcelo B. Jatene (SP) Alfredo Inácio Fiorelli (SP) Wilson Lopes Pereira (SP) Rui M. S. Almeida (PR) Melchior Luiz Lima (ES) Miguel Angel Maluf (SP)


SOCIEDADE BRASILEIRA DE CIRURGIA CARDIOVASCULAR BRAZILIAN SOCIETY OF CARDIOVASCULAR SURGERY E-mail: revista@sbccv.org.br Sites: www.scielo.br/rbccv www.rbccv.org.br


REVISTA BRASILEIRA DE CIRURGIA CARDIOVASCULAR

ISSN 1678-9741 - Publicação online ISSN 0102-7638 - Publicação impressa RBCCV 44205

Impact Factor: 1.239

BRAZILIAN JOURNAL OF CARDIOVASCULAR SURGERY Rev Bras Cir Cardiovasc, (São José do Rio Preto, SP - Brasil) apr/jun - 2012;27(2):187-346

CONTENTS/SUMÁRIO

EDITORIALS/EDITORIAIS New Impact Factor: 1.239. Goal is to surpass 1.5 in 2013 Domingo M. Braile ....................................................................................................................................................................... I On-and off-pump coronary artery bypass surgery. The heart surgeon should master both techniques Walter J. Gomes ........................................................................................................................................................................... V Pediatric cardiovascular surgery: what we must preserve, what we should improve and what we must transform Luis Fernando Caneo ................................................................................................................................................................. IX The risk of risk scores and the dream of BraSCORE Omar Asdrúbal Vilca Mejía, Luiz Augusto Ferreira Lisboa ...................................................................................................... XII

ORIGINAL ARTICLES/ARTIGOS ORIGINAIS 1370

Validation of the 2000 Bernstein-Parsonnet and EuroSCORE at the Heart Institute - USP Validação do 2000 Bernstein-Parsonnet e EuroSCORE no Instituto do Coração - USP Omar Asdrúbal Vilca Mejía, Luiz Augusto Ferreira Lisboa, Luis Alberto Oliveira Dallan, Pablo Maria Alberto Pomerantzeff, Luiz Felipe Pinho Moreira, Fabio Biscegli Jatene, Noedir Antonio Groppo Stolf ........................................................................... 187

1371

Comparison of electrophysiological parameters of septal and apical endocardial cardiac stimulation Comparação de parâmetros eletrofisiológicos das estimulações cardíacas endocárdicas septal e apical Juan Carlos Pachón Mateos, José Carlos Pachón Mateos, Remy Nelson Albornoz Vargas, Enrique Indalécio Pachón Mateos, Khalil Cosac, Hugo Belloti Lopes, Fabrizio Achilles Soares, Amanda Guerra Moraes Rego Sousa ......................................... 195

1372

Preoperative risk factors for mediastinitis after cardiac surgery: analysis of 2768 patients Fatores de risco pré-operatórios para mediastinite após cirurgia cardíaca: análise de 2768 pacientes Marcos Gradim Tiveron, Alfredo Inácio Fiorelli, Eduardo Moeller Mota, Omar Asdrúbal Vilca Mejia, Carlos Manuel de Almeida Brandão, Luís A. O. Dallan, Pablo A. M. Pomerantzeff, Noedir A.G. Stolf ............................................................................. 203

1373

Impact of socio-economic profile on the prosthesis type choice used on heart surgery Impacto do perfil socioeconômico na escolha da prótese valvar em cirurgia cardíaca André Maurício S. Fernandes, Larissa Santana Bitencourt, Igor Nogueira Lessa, Agnaldo Viana, Felipe Pereira, Gabriel Bastos, Cristiano Ricardo Bastos de Macedo, Roque Aras Júnior ........................................................................................................ 211

1374

Risk factors for low cardiac output syndrome after coronary artery bypass grafting surgery Fatores de risco para síndrome de baixo débito cardíaco após cirurgia de revascularização miocárdica Michel Pompeu Barros de Oliveira Sá, Joana Rosa Costa Nogueira, Paulo Ernando Ferraz, Omar Jacobina Figueiredo, Wagner Cid Palmeira Cavalcante, Thiago Cid Palmeira Cavalcante, Hugo Thiago Torres da Silva, Cecília Andrade Santos, Renato Oliveira de Albuquerque Lima, Frederico Pires Vasconcelos, Ricardo de Carvalho Lima ........................................................................... 217


1375

Heart defects treatment in Sergipe: propose of resources’ rationalization to improve care Tratamento das cardiopatias congênitas em Sergipe: Proposta de racionalização dos recursos para melhorar a assistência Debora Cristina Fontes Leite, José Teles de Mendonça, Rosana Cipolotti, Enaldo Viera de Melo .......................................... 224

1376

Six-minute walk test as a tool for assessing the quality of life in patients undergoing coronary artery bypass grafting surgery Teste de caminhada de seis minutos como ferramenta para avaliar a qualidade de vida em pacientes submetidos à cirurgia de revascularização miocárdica Vanessa Cristina Baptista, Luciana Campanatti Palhares, Pedro Paulo Martins de Oliveira, Lindemberg Mota Silveira Filho, Karlos Alexandre de Souza Vilarinho Elaine Soraya Barbosa de Oliveira Severino, Carlos Fernando Ramos Lavagnoli, Orlando Petrucci ....................................................................................................................................................................... 231

1377

Predicted preoperative maximal static respiratory pressures in adult cardiac surgeries: evaluation of two formulas Pressões respiratórias máximas no pré-operatório de cirurgias cardíacas em adultos: avaliação de duas fórmulas Ricardo Kenji Nawa, Ada Clarice Gastaldi, Elisângela Aparecida Soares da Silva, Viviane dos Santos Augusto, Alfredo José Rodrigues, Paulo Roberto Barbosa Evora ................................................................................................................................. 240

1378

Use of intra-aortic balloon pump in cardiac surgery: analysis of 80 consecutive cases Uso do balão intra-aórtico no trans e pós-operatório de cirurgia cardíaca: análise de 80 casos consecutivos Fernando Pivatto Júnior, Ana Paula Tagliari, Anderlise Bard Luvizetto, Edemar Manuel Costa Pereira, Erci Maria Onzi Siliprandi, Ivo Abrahao Nesralla, Rodrigo Pires dos Santos, Renato Abdala Karam Kalil ......................................................................... 251

1379

Calcium dobesilate may improve hemorheology in patients undergoing coronary artery bypass grafting Dobesilato de cálcio pode melhorar hemorreologia em pacientes submetidos à cirurgia de revascularização miocárdica Kazim Besirli, Birsen Aydemir, Caner Arslan, Ali Riza Kiziler, Emir Canturk, Bekir Kayhan ............................................... 260

1380

Results of aortic valve surgery in patients over 75 years old, at 4.5 years of follow-up Resultados da cirurgia por estenose aórtica em pacientes acima de 75 anos, em 4,5 anos de seguimento Ana Paula Tagliari, Fernando Pivatto Júnior, Felipe Homem Valle, João Ricardo Michielin Sant’Anna, Paulo Roberto Prates, Ivo Abrahão Nesralla, Renato Abdala Karam Kalil ......................................................................................................................... 267

1381

Fetal cardiac output and ejection fraction by spatio-temporal image correlation (STIC): comparison between male and female fetuses Débito cardíaco e fração de ejeção fetal por meio do spatio-temporal image correlation (STIC): comparação entre fetos masculinos e femininos Christiane Simioni, Edward Araujo Júnior, Wellington P. Martins, Liliam Cristine Rolo, Luciane Alves da Rocha, Luciano Marcondes Machado Nardozza, Antonio Fernandes Moron ...................................................................................................................... 275

1382

Flowmetry of left internal thoracic artery graft to left anterior descending artery: comparison between on-pump and offpump surgery Fluxometria da artéria torácica interna esquerda na revascularização da artéria descendente anterior com e sem circulação extracorpórea Filinto Marques de Cerqueira Neto, Marco Antonio Vieira Guedes, Leonardo Eugênio Fonseca Soares, Gustavo Santiago Almeida, André Raimundo F Guimarães, Mauricio Alves Barreto, Emerson Costa Porto, Álvaro Rabelo Júnior ................................. 283

1383

Initial experience with Pomerantzeff´s technique for reduction of the size of giant left atrium Experiência inicial com a técnica de Pomerantzeff para redução do tamanho do átrio esquerdo gigante Jocerlano Santos de Sousa, Pablo Maria Alberto Pomerantzeff, Carlos Manuel de Almeida Brandão, Lisandro Azeredo Gonçalves, Marcos Gradim Tiveron, Marcelo Luiz Campos Vieira, Flavio Tarasoutchi, Noedir Antônio Groppo Stolf ........................... 290

REVIEW ARTICLES/ARTIGOS DE REVISÃO 1384

Point-of-care test (POCT) INR: hope or illusion? RNI Point-of-care test (POCT): Esperança ou ilusão? Luci Maria Sant’Ana Dusse , Nataly Carvalho Oliveira, Danyelle Romana Alves Rios, Milena Soriano Marcolino .............. 296

1385

Cardiology in Brazilian scientific journals: an overview Cardiologia em revistas científicas brasileiras: um panorama Kavita Kirankumar Patel, Mauricio Rocha e Silva ................................................................................................................... 302

1386

Conservative surgical management of mitral insufficiency: an alternative approach Tratamento cirúrgico conservador da insuficiência mitral: uma abordagem alternativa Francisco Gregori Junior ........................................................................................................................................................... 312


SPECIAL ARTICLE/ARTIGO ESPECIAL 1387

Greek language: analysis of the cardiologic anatomical etymology: past and present Idioma grego: análise da etimologia anatomocardiológica: passado e presente Georges Bezas, Alexandre Lins Werneck .................................................................................................................................. 318

CASE REPORT/RELATO DE CASO 1388

Heart retransplantation in children without the use of blood product Retransplante cardíaco em criança sem o uso de hemoderivados Antonio Alceu dos Santos, José Pedro da Silva, Luciana da Fonseca, José Francisco Baumgratz ............................................ 327

MY OPINION/OPINIÃO 1389

The medical education and the Unified Health System Alexandre V. Brick .................................................................................................................................................................... 331

1390

Evidence-Based Medicine - New Paradigm or Pseudoscience? Marcelo Derbli Schafranski ...................................................................................................................................................... 334

LETTERS/CARTAS 1391

Letter to the Editor Cartas ao Editor ........................................................................................................................................................................ 338

Impresso no Brasil Printed in Brazil

Projeto Gráfico: Heber Janes Ferreira Impressão e acabamento:


SOCIEDADE BRASILEIRA DE CIRURGIA CARDIOVASCULAR BRAZILIAN SOCIETY OF CARDIOVASCULAR SURGERY E-mail: revista@sbccv.org.br Sites: www.scielo.br/rbccv www.rbccv.org.br


Editorial

New Impact Factor: 1.239. Goal is to surpass 1.5 in 2013 Domingo M. BRAILE*

DOI: 10.5935/1678-9741.20120029

he new Impact Factor (IF) of the Brazilian Journal of Cardiovascular Surgery (BJCVS) is 1.239. The relationship was announced in late June, by ISIThomson Reuters. This represents a significant growth of 30% compared to last year’s rate of 0.963. We are now ranked the 6th journal of national scientific publications and the 1st of the surgical area. The Immediacy Index is 0.329, the second highest among the top 20 Brazilian journals listed in ISI. For comparison, the Annals of Thoracic Surgery has IF = 3.741, the Journal of Thoracic and Cardiovascular Surgery has IF= 3.406 and the European Journal of Cardio-Thoracic Surgery has IF = 2.550. We are the fifth journal of the specialty in the world ranking. To CAPES, we are still classified in Medicine I - II and III as B2 stratum = 40 points without limits, however we are B1 = 60 points, without limits, in the areas of Physical

T

Education, Nursing and Veterinary Medicine. To reach BI in Medicines I - II and III we will have to reach an IF above 1.599. That is our goal for 2013. Figure 1 shows the journals that cited the BJCVS and Figure 2 compares the number of citations from other journals in BJCVS and vice versa, we cite a lot more than we have been cited in most journals. We note, however, that we are being cited in foreign journals, which should increase with the facilities that have implemented this year, as the EPUB and FLIP. In addition to celebrate the new IF, this edition of the Brazilian Journal of Cardiovascular Surgery (BJCVS) marks the beginning of a new stage. After long deliberations between the Editorial Board of the Journal and the Board of the Brazilian Society of Cardiovascular Surgery (BSCVS), with the approval of the General Assembly during the 39th Brazilian Congress of Cardiovascular Surgery, it was

I


Fig. 1 - Chart showing which journals cited BJCVS

Fig. 2 - Chart comparing the number of BJCVS citations in other journals and vice versa

decided to perform a drastic reduction in the number of copies printed. As the matter was of interest to the members, statutorily, the question was under discussion during the General Assembly. By overwhelming majority, it was chosen to accept the suggestion, however, before consulting the partners so that those who wished to continue receiving the printed version could manifest. The consultation was made by electronic means in the month of May. With those who chose to continue to receive II

the printed version, educational institutions, sponsors, peers, Scielo, Pubmed, Thompson Reuters, EBSCO, SCImago and others, in addition to copies that will be in the collection of BSCVS and BJCVS, it totalized the demand of 200 copies. This corresponds to about one sixth of that volume was printed until issue 27.1 and will provide considerable savings in printing and postage, funds to be invested in the acquisition of software to enhance and streamline the electronic edition, as well as improve the structure and professionalize the translation of articles into


English, a fundamental factor to be more readable and therefore cited. Furthermore, this decision follows the current world trend of keeping electronic editions as the primary means of disseminating scientific journals. It also contributes, of course, to preserve the environment by saving paper. The electronic BJCVS in its online edition, can be accessed in full and free, in many ways, in the sites www.rbccv.org.br or www.bjcvs.org or even www.scielo.br/ rbccv in various formats (HTML, PDF, and FLIP, desktops and laptops). Ii is also available in full version in modern and universal ePub (Electronic Publication) for iPads, iPhones and the like, enabling the use of advanced information technologies. This includes unimaginable electronic benefits before scanning. An immediate consequence is the enormous benefit of no longer depending exclusively on the “Keywords” to find the item or service, since we can make the search for the desired subject by submitting just one word that describes it. In the English edition of BJCVS, there is a difference of great value. For any term that is not understood, the reader can just press it with his finger and choose the option “set”, then displays an English-English dictionary with the meaning of the word. There are many other facilities, which will soon be perceived by our attentive readers. This diversity of electronic media in which BJCVS is available has as a consequence, an increase in the number of potential readers, which together with the provision in the various databases, such as SciELO, Google Scholar, PubMed, Scopus, EMBASE, EBSCO and ISI-Thomson, among others, allows the increase in the number of articles cited, reflecting the impact factor. These innovations we have implemented, always with the support of the Boards of BSCVS, since I assumed the post of Chief Editor of BJCVS in 2002, reinforce our commitment to deliver a publication increasingly robust in terms of content and form. Over time, it manifested itself as a vehicle for the dissemination of Brazilian Cardiovascular Surgery, which since the middle of last century [1] has shown vigorous and active, even if not always providing the ideal conditions for working of professionals. On the other hand, international integration is gradually being established, by the recognition of experts around the world. That confidence was evident at the 39th Congress of the BSCVS in Maceió. The Board of BSCVS and Organizing Committee, coordinated by Dr. José Wanderley Neto, did a tireless work, which was reflected in the high-level scientific activities, besides the continuity of skills sessions: Hands On, thanks to the dedicated work of many, led by the indefatigable former president Gilberto Barbosa.

The Techno College also proved to be useful for members, offering a quick and proactive update of the latest techniques. All these innovations have become tradition, incorporating the very latest in learning teaching methods. Always concerned with the updating of surgeons in Brazil each year, the Board of BSCVS seeks new models of education in different areas, so that we can always be renewed with the knowledge, an example for other medical societies. Another point of outstanding importance is a result of fraternization among peers, allowing us to continue united in the ideal inherited from the pioneers, striving together for the best patient care, ideal working conditions for colleagues and behavioral harmony essential to the welfare of community that surrounds us. With each passing year, the congress is no longer “exclusivity” of cardiac surgeons, adding professionals of related fields, such as nurses, physiotherapists, psychologists, engineers and perfusionists. Academics have also greatly participated, presenting studies of high scientific value, demonstrating that the future is in good hands. Among the studies of heart surgery, Free Themes winners were: 1st place: “Comparison of cardiac histology and left ventricular function after transplantation of purified endothelial progenitor cells and expanded in the infarcted myocardium of rats”, presented by former President, Dr. Paulo Brofman (PR) and colleagues, 2nd place: “Autologous bone marrow stem cells and physical activity after myocardial infarction in rats”, presented by Dr. Luiz Cesar Guarita Souza (PR) and colleagues; 3rd place (tied): “Metaanalysis of 6136 patients treated with percutaneous coronary intervention with drug-eluting stents or coronary artery bypass surgery for stenosis of unprotected left main coronary artery”, presented by Dr. Michel Pompeu Sá (PE) and colleagues, and “Activity of the enzyme glucose 6phosphate dehydrogenase in acute right ventricular hypertrophy underwent banding of the pulmonary trunk in adults”,presented by Dr. Leonardo Miana (MG) and colleagues. Posters: 1st place: “Follow-up and evolution of the Braile’s Inovare transcatheter prosthesis implantation” presented by Dr. Diego Gaia (SP) and colleagues, 2nd place: “In vitro study of the effect of crimping on pericardium fibrillar structures of the Inovare transcatheter bioprostheses” presented by Dr. Marcus Gimenez (SP) and colleagues, 3rd place (tied): “Hybrid procedure in treating the syndrome of hypoplastic left heart (HLHS) and anatomic variants: results in 35 neonates”, presented by Dr. Marcelo Jatene (SP) and colleagues, and “Benefit from the elimination of early vs late CNI and introduction of everolimus in HTx recipients, long-term follow-up”, presented by Dr. Arnt Fiane (Norway) and colleagues. III


The BSCVS Award of Professional of the Year was awarded to Dr. José Wanderley Neto for his brilliant work in favor of cardiac surgery in the Northeast and Brazil over the past decades. To him, my compliments. The time now is wait for the 40th Congress, which promises to be an even bigger success. I register with joy, the gratitude for the homage, at the Closing Dinner, to me, to Editor, Ricardo Brandau, and editorial assistant, Rosângela Monteiro, by dedication and competence shown by the Journal of Cardiovascular Surgery (BJCVS), positioning it among the top five Journals on Cardiovascular Surgery of the world. This homage is a great honor for us and encourages work harder for the Journal. We are making available to interested parties a further category of manuscripts: “Images in Cardiovascular Surgery”. The text should be up to 300 words, including title and references, and a maximum of two images, which are currently below the required standard (wider than 1000 pixels and DPI equal to or greater than 200). All contributions and suggestions are welcome. In this edition, there are four items available for testing by the system of Continuing Medical Education (CME): “Comparison of electrophysiological parameters of septal

IV

and apical endocardial cardiac stimulation”, page 195, “Risk factors for low cardiac output syndrome after coronary artery bypass grafting”, page 217, “Use of an intra-aortic balloon in the trans- and postoperative cardiac surgery: analysis of 80 consecutive cases”, page 251, and “INR Pointof-care test (POCT): Hope or Illusion?”, page 296. With the certainly that the Brazilian Cardiac Surgery is a marker of the viability of our country, I wish all good reading.

My warmest regards,

*Editor in Chief BJCVS

REFERENCE 1. Braile DM, Godoy MF. História da cirurgia cardíaca no mundo. Rev Bras Cir Cardiovasc. 2012;27(1):125-34.


Editorial

On-and off-pump coronary artery bypass surgery. The heart surgeon should master both techniques Cirurgia de revascularização miocárdica com e sem circulação extracorpórea. O cirurgião cardíaco deve dominar ambas as técnicas

Walter J. Gomes1

DOI: 10.5935/1678-9741.20120030

Coronary artery bypass grafting (CABG) has reinforced its importance in the treatment of coronary artery disease (CAD) with the latest scientific evidence, proving to be the most effective in improving patient outcomes when compared to other therapies, such as drug or interventionist, especially in high risk patients. However, controversy remains as to the technique to be employed, particularly with regard to employment or not of cardiopulmonary bypass (CPB). The OPCABG emerged as an alternative technique to avoid the deleterious effects of CPB, which negatively affect the outcome of MRI, notably the systemic inflammatory response syndrome, which leads to complications, inducing organ dysfunction, and the need for cannulation and aortic clamping which increases the incidence of cerebrovascular accident (CVA). With the increasing complexity of cases referred for surgery, these complications can compromise the expected result and the implicit benefit for patients, especially those with higher morbidity and older. However, OPCAB surgery has been questioned regarding its efficacy and safety in comparison to the conventional technique, especially with the outcomes related to incomplete revascularization and quality of grafts. In this issue of BJCVS, the findings of the study by

Cerqueira Neto et al. [1] [pg. 283] reinforce that the quality of the anastomosis of the left internal thoracic artery (LITA) to left anterior descending artery (LAD) is similar, with fluxometric data showing no difference between them, either performed with or without CPB. Unfortunately, there was no comparison with the grafts to other areas of the heart, what would allow additional information and verifying that the results also apply. However, the anastomosis of the LITA to LAD stands today as the only strategy in CABG surgery that increases survival.

1. Associated Professor; Full Professor of the Discipline of Cardiovascular Surgery. Escola Paulista de Medicina - Federal University of São Paulo. Associated Editor of the Brazilian Journal of Cardiovascular Surgery and São Paulo Medical Journal. President of the Brazilian Society of Cardiovascular Surgery, São Paulo, SP, Brasil.

Correspondence address: Walter J. Gomes. Rua Borges Lagoa, 1080 cj 608 – São Paulo, SP Brasil – CEP 04038-002 E-mail wjgomes.dcir@epm.br

READ THE ORIGINAL ARTICLE ON PAGES 283-289 The quality of anastomosis in off-pump surgery is implicitly related to surgeon experience. While experienced surgeons performing the technique reported the same degree of patency of the techniques over 8 years of followup [2,3] in assays in which less experienced surgeons operated, the results were inferior and high intraoperative conversion rates as described in the Rooby study [4]. Similarly, while more experienced surgeons tend to perform more complete revascularization, other surgeons reported low outcomes.

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Meta-analyzes that compared the two strategies have shown similar results, with a tendency to favor survival and other outcomes in OPCAB [5], although other studies have shown negative results. The Rooby study demonstrated worse prognosis with this technique and a published meta-analysis suggested a higher mortality rate with off-pump technique [6]. The most recent published meta-analysis examined 59 trials, comprising 8966 patients and showed that off-pump surgery reduces the incidence of stroke by 30% compared to the conventional technique, with no difference in the outcomes of 30-day mortality and perioperative infarction, which were not affected by age, gender and number of grafts [7]. The concept of incomplete revascularization has been changing and new knowledge brought have changed this dogmatic and stereotyped plea, whose different settings involved in controversies about results in the medium and long term. Although complete revascularization is considered superior to incomplete revascularization, with better survival and lower reintervention in the long term, it is not yet clear whether this difference is a direct consequence of incomplete revascularization or if this approach is merely a marker of more severe coronary disease and complex with more rapid progression. Currently, it is discussed if indeed incomplete revascularization may negatively affect longterm outcome or may be the optimal treatment strategy in selected cases of high-risk patients, minimizing risk of perioperative mortality and morbidity and possibly allowing a safer revascularization. Thus, the analysis of the follow-up of 5 years of MASS III study comparing 308 patients undergone surgery with and without CPB, showed that the number of grafts per patient was higher in the on-pump group than in the offpump group (2.97 vs. 2 , 49, P <0.001), but no difference between groups in long-term outcomes (death, myocardial infarction, new revascularization or stroke). [8] In the BARI trial, complete or incomplete revascularization had no impact on results in 7 years follow-up of patients [9]. Likewise, data from three years of the SYNTAX trial reported the incidence and predictors of incomplete revascularization after percutaneous coronary intervention (PCI) or CABG, while incomplete revascularization was associated with adverse events after PCI, and compared to MRI there was no difference between groups. The rate of incomplete revascularization was 43% for PCI and 37% for MRI, reinforcing that the incidence of incomplete revascularization was higher in patients with more complex coronary artery disease, as patients enrolled in SYNTAX, reflecting our current practice [10]. In the study group of Leipzig, in a cohort of 8806 patients undergoing CABG with multivessel disease in which VI

approximately 10% had incomplete revascularization (within the circumflex artery and the right coronary artery, but with all the LITA grafted to the LAD) there was no difference in survival at 3 years follow-up compared to those with complete revascularization. The incomplete revascularization was five times more frequent in patients with more complex coronary heart disease. The authors conclude that, in the presence of LITA grafted to the LAD and other arteries (circumflex and right coronary) of poor quality, incomplete revascularization did not affect survival in the short or long term and may be a good therapeutic option and should be balanced with the risks [11]. The anatomical criteria (SYNTAX score) and ischemic functional tests have been challenged in the estimation of the risk profile in incomplete revascularization. The FAME study randomized 1005 patients with multivessel CAD to complete anatomic revascularization (PCI in vessels of adequate size, with stenoses of 50% to 100%) against physiological incomplete revascularization based on fractional flow reserve <0.80. The anatomically incomplete revascularization, but configuring a complete ischemic revascularization resulted in a 34% lower relative risk of death or myocardial infarction at one year [12]. The CORONARY study, the largest prospective randomized trial performed so far comparing strategies for CABG with and without CPB, reported the results of 30 days involving 4752 patients and showed no significant difference in the primary composite endpoint (death, myocardial infarction, stroke or renal failure requiring dialysis) between the two techniques. The off-pump group showed a lower incidence of acute renal failure, reducing the duration of mechanical ventilation and the incidence of reoperation for bleeding, and lower rates of blood transfusions and decreased respiratory complications. However, there were fewer grafts and increased risk of repeated revascularization. Interestingly, for the composite endpoint in this study, patients operated in South America had statistically better with OPCAB than with CPB [13]. The DOORS study randomized 900 patients elderly (> 70 years) for CABG with and without CPB, including surgeons with intermediate experience in off-pump surgery. Results at 30 days showed no statistical difference between the two techniques, the composite endpoint of death, MI and stroke [14]. The guidelines for revascularization of the European Society of Cardiology 2010 and the American societies published in 2011 reinforce the indications for use of offpump CABG in selected patients and with greater severity. They recommend OPCAB in patients with mild to moderate chronic renal insufficiency, with calcified aorta and consequent increased risk of intraoperative stroke (in this case, the technique of no-touch aorta is specifically recommended), after angioplasty without success and also


in patients with coagulation disorders, where without using CPB may benefit the patient [15,16]. Likewise, in 2011, the National Institute for Health and Clinical Excellence (NICE) has issued a document update in OPCAB surgery, which, after review of the published evidence, which reinforces that the safety and effectiveness are adequate to support its use, since the conditions for clinical use are provided, patient consent and data audit. The NICE document emphasizes that OPCAB may also be particularly useful in patients with left ventricular dysfunction, advanced aortic atherosclerosis and the elderly [17]. It should be emphasized that the property of off-pump CABG in reducing stroke event is related to surgical technique, which effectively only the no-touch technique of the ascending aorta reduces the risk of neurological damage. The multiple manipulations of the ascending aorta required by conventional surgery promote atheromatous embolization, providing the probable mechanism for the increased risk of stroke. Depending on the particular technique used in OPCAB, there is elimination of 2 or 3 of these aortic manipulations maneuvers. Most studies comparing CABG with and without CPB used the partial clamping of the ascending aorta to the construction of the proximal anastomoses of vein grafts, eliminating the plausible protective power of OPCAB. Additionally, current guidelines also recommend the intraoperative measure of graft flow, which can be especially useful in OPCAB in order to reduce the incidence of early grafts occlusion. In the economic aspect, off-pump surgery has shown to reduce the cost of the procedure in our country, which constitutes an additional advantage in a country like ours, with serious constraints of health budget and with welfare hospitals tending to become budgeted. The substudy of MASS-III, comparing the costs of the two techniques showed that in OPCAB, there was decreased operating expenses and that the economy could increase the ability to care for patients by 25% [18,19]. In short, the training, the experience of the surgical team and the organizational aspect is fundamental in achieving results on the MRI, but more sharply in OPCAB technique. Specific subgroups of patients may benefit from more than one technique or the other, while a patient with chronic renal failure may benefit most from OPCAB, another diabetic patient with very ill arteries might need complete revascularization with CPB using both ITAs. Both techniques should therefore be seen as complementary and not antagonistic, with property used to provide the best outcome for our patients. In this context, the emerging data suggests that an additional beneficial to patients can be obtained if the surgeon and staff dominate the two techniques and, therefore, must now be trained in both.

REFERENCES 1. Cerqueira Neto FM, Guedes MAV, Soares LEF, Almeida GS, Guimarães ARF, Barreto MA, et al. Fluxometria da artéria torácica interna esquerda na revascularização da artéria descendente anterior com e sem circulação extracorpórea. Rev Bras Cir Cardiovasc. 2012;27(2):283-9 2. Puskas J, Williams WH, Mahoney EM, Huber PR, Block PC, Duke PG, et al. Off-pump vs. conventional coronary artery bypass grafting: early and 1-year graft patency, cost, and quality-of-life outcomes: a randomized trial. JAMA. 2004;291(15):1841-9. 3. Angelini GD, Culliford L, Smith DK, Hamilton MC, Murphy GJ, Ascione R, et al. Effects of on- and off-pump coronary artery surgery on graft patency, survival, and health-related quality of life: long-term follow-up of 2 randomized controlled trials. J Thorac Cardiovasc Surg. 2009;137(2):295-303. 4. Shroyer AL, Grover FL, Hattler B, Collins JF, McDonald GO, Kozora E, et al. On-pump versus off-pump coronary-artery bypass surgery. N Engl J Med. 2009;361(19):1827-37. 5. Kuss O, von Salviati B, Börgermann J. Off-pump versus onpump coronary artery bypass grafting: a systematic review and meta-analysis of propensity score analyses. J Thorac Cardiovasc Surg. 2010;140(4):829-35. 6. Møller CH, Penninga L, Wetterslev J, Steinbruchel DA, Gluud C. Off-pump versus on-pump coronary artery bypass grafting for ischaemic heart disease. Cochrane Database Syst Rev. 2012;3:CD007224. 7. Afilalo J, Rasti M, Ohayon SM, Shimony A, Eisenberg MJ. Off-pump vs. on-pump coronary artery bypass surgery: an updated meta-analysis and meta-regression of randomized trials. Eur Heart J. 2012;33(10):1257-67. 8. Hueb W, Lopes NH, Pereira AC, Hueb AC, Soares PR, Favarato D, et al. Five-year follow-up of a randomized comparison between off-pump and on-pump stable multivessel coronary artery bypass grafting. The MASS III Trial. Circulation. 2010;122(11 Suppl):S48-52. 9. Vander Salm TJ, Kip KE, Jones RH, Schaff HV, Shemin RJ, Aldea GS, et al. What constitutes optimal surgical revascularization? Answers from the Bypass Angioplasty Revascularization Investigation (BARI). J Am Coll Cardiol. 2002;39(4):565-72. 10. Kappetein AP, Feldman TE, Mack MJ, Morice MC, Holmes DR, Ståhle E, et al. Comparison of coronary bypass surgery with drug-eluting stenting for the treatment of left main and/or three-vessel disease: 3-year follow-up of the SYNTAX trial. Eur Heart J. 2011;32(17):2125-34. 11. Rastan AJ, Walther T, Falk V, Kempfert J, Merk D, Lehmann S, et al. Does reasonable incomplete surgical revascularization affect early or long-term survival in patients with multivessel

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coronary artery disease receiving left internal mammary artery bypass to left anterior descending artery? Circulation. 2009;120(11 Suppl):S70-7. 12. Tonino PA, De Bruyne B, Pijls NH, Siebert U, Ikeno F, van't Veer M; FAME Study Investigators, et al. Fractional flow reserve versus angiography for guiding percutaneous coronary intervention. N Engl J Med. 2009;360(3):213-24. 13. Lamy A, Devereaux PJ, Prabhakaran D, Taggart DP, Hu S, Paolasso E; CORONARY Investigators, et al. Off-pump or on-pump coronary-artery bypass grafting at 30 days. N Engl J Med. 2012;366(16):1489-97. 14. Houlind K, Kjeldsen BJ, Madsen SN, Rasmussen BS, Holme SJ, Nielsen PH, et al. On-pump versus off-pump coronary artery bypass surgery in elderly patients: results from the Danish on-pump versus off-pump randomization study. Circulation. 2012;125(20):2431-9. 15. Task Force on Myocardial Revascularization of the European Society of Cardiology (ESC) and the European Association for Cardio-Thoracic Surgery (EACTS); European Association for Percutaneous Cardiovascular Interventions (EAPCI), Kolh P, Wijns W, Danchin N, Di Mario C, Falk V, Folliguet T, et al. Guidelines on myocardial revascularization. Eur J Cardiothorac Surg. 2010;38 (Suppl):S1-S52.

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16. Hillis LD, Smith PK, Anderson JL, Bittl JA, Bridges CR, Byrne JG; American College of Cardiology Foundation; American Heart Association Task Force on Practice Guidelines; American Association for Thoracic Surgery; Society of Cardiovascular Anesthesiologists; Society of Thoracic Surgeons, et al. 2011 ACCF/AHA Guideline for Coronary Artery Bypass Graft Surgery. A report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Developed in collaboration with the American Association for Thoracic Surgery, Society of Cardiovascular Anesthesiologists, and Society of Thoracic Surgeons. J Am Coll Cardiol. 2011;58(24):e123-210. 17. National Institute for Health and Clinical Excellence. Off-pump coronary artery bypass grafting. Interventional procedure guidance 377. Disponivel em: http://guidance.nice.org.uk/ IPG377. 18. Girardi P, Hueb W, Nogueira CR, Takiuti M, Nakano T, Garzillo CL, et al. Custos comparativos entre a revascularização miocárdica com e sem circulação extracorpórea. Arq Bras Cardiol. 2008;91(6):369-76. 19. Gomes WJ, Braile DM. On-pump versus off-pump coronary artery bypass surgery: the impact on costs of health care systems. Arq Bras Cardiol. 2008;91(6):338-9.


Editorial

Pediatric cardiovascular surgery: what we must preserve, what we should improve and what we must transform

Luiz Fernando Caneo1

Cardiac surgery has been available for many years in several developing countries, thanks to the creativity and hard work of individuals who were able to produce good work in spite of the limited resources. Rodolfo Neirotti

DOI: 10.5935/1678-9741.20120031

It is really evident how the lack of sustainable pediatric surgical services in developing or emerging countries is responsible for a significant number of preventable deaths and complications from heart disease potentially treatable. The more we approach the developed world, the more congenital heart disease contributes to the number of preventable deaths in the neonatal period and first year of life. In this context, pediatric cardiac surgery represents perhaps one of the biggest challenges for our country Taking into consideration all those facts, we started to ask what should be preserved, which can be done to improve, by whom, and how and what we must transform. What we must preserve Scientific contributions in pediatric surgery, as the arterial switch operation, the Teles technique for coarctation of the aorta, the Barbero-Marcial technique for correction of common arterial trunk in the past and more recently, the

1 . Cardiovascular surgeon. Medical Assistant, Heart Institute, Hospital das Clinicas, School of Medicine, University of Sao Paulo, Sao Paulo, Brazil.

Cone technique, by JosĂŠ Pedro da Silva, for the treatment of Ebstein, are examples of the creativity, expertise and innovation of our surgeons. The labor force in our culture of care is very striking and made our surgery, while dependent on individual effort, always stand out in the local and global scenario. Leadership, tolerance, perseverance, dedication and adaptability have been the key to success, but not necessarily ensure sustainability. Making pediatric cardiac surgery a reality in Brazil is the work of “a few men for a great challengeâ€? [1]. READ ORIGINAL ARTICLE ON PAGES 224-230 What we must improve In countries as Brazil, where there are many priorities in public health, pediatric cardiac surgery is often considered a secondary problem to be solved. This explains the number of children undergoing surgery, which does not reach 40% of the demand population scenarios, depending on the region of the country [2]. This situation worsens when analyzing the numbers of newborns operated on the most complex procedures carried out. Few places are prepared IX


to perform neonatal surgery and many have limited capacity due to excessive demand. It is hard to imagine the number of children progressing with secondary pulmonary hypertension to a non-operated interventricular communication or a myocardial dysfunction due to an obstructive lesion. The structural problems are not the only difficulties we have to face, since the shortage of human resources is obvious and concerning in many regions. It is not only the lack of surgeons, lack of pediatric cardiologists, specialist nurses and all other professionals. In a complex system such as pediatric cardiac surgery, the surgical outcome depends not only on technical factors, but it is the result of organizational, personal facts and their interactions [3]. “No human investigation can claim to be scientific if it does not pass the test of mathematical proof.” - Leonardo Da Vinci. In Brazil, the evaluation of surgical results is only possible through the government data, the DATASUS. A more detailed analysis of these data is very difficult to achieve, both by the procedures terminology used by the government, and the difficulty in risk stratification of procedures performed. We still do not a national data bank, and there are few centers that participate in international databases or have the culture to analyze their results. Information a bit more detailed, specific diseases, are presented in congresses or scientific articles, but often do not reflect the totality of the operated cases and do not represent the reality of care assistance. In addition, most of them have focused only on the success and rarely discuss the problems and the reasons for unsatisfactory results. This issue has caused much concern to the population and the government for being ignored for a long time, and especially the cardiovascular surgeon, who lives with the severity of the problem and realize that the current situation is unacceptable. The current system of care for children with heart disease is inefficient. What we must transform Transforming the model based on individual performance in a real program of pediatric cardiac surgery in a systematic way may be one of our biggest challenges. Recognizing the reality, accepting our failures and rethink the model seems to be a good start. Go beyond our technical qualities means rewriting our institutions, their processes and way of working in the high complexity health system. The need for collaboration in solving these problems is increasingly evident. The creation of the Department of Pediatric Cardiac Surgery, within our specialty society in 2003, allowed deeper discussion of the problems and the opportunity to find solutions adapted to adversity and regional differences. Since then, meetings have occurred X

in order to discuss the present scenario, education and training. More recently, a struggle in the search for solutions was triggered in conjunction with the Brazilian Society of Cardiology and the Brazilian Society of Interventional Cardiology. In order to build a national program of assistance to children with congenital heart disease to be submitted to the federal government, our society has proved to be in a well-defined and consolidated position. In this edition of the BJCVS, the article “Treatment of congenital heart disease in Sergipe: proposed rationalization of human resources to improve care,” Milk et al. [4], represents the effort of a group of people to organize and structure the health system of a state, with regard to the care of children with congenital heart disease. It is so exemplary that the authors put into practice some important points, such as optimization of existing resources and the centralization of high complexity care. They present the data in a structured, distributed complexity, and perform a critical analysis of the results observed. They also objectively demonstrate superior results in the number of procedures performed, decreased mortality, increased number of children served and an increase in the number of complexity, after the centralization of surgery at a single hospital. That is the result of people’s work that was not limited only to their prior technical contributions, but realized that they can go beyond the operating room and act directly in the government health system by creating, suggesting and implementing actions that can surely modify their own technical results. Unfortunately, solutions based on personal effort cannot be sustained. Only the interdependence of the components listed below can ensure the preservation, improvement and transformation of our current scenario (Neirotti RA, personal communication): % Local and federal government: through the implementation of health policies and ensuring the appropriate resources needed to finance it, considering that most of the patients depend on the Unified Health System. % Universities and other educational institutions: increasing its human capital through improving the quality of education. % Specialty societies: contributing their knowledge and ability to defend the practice of the specialty. % Hospital institutions: promoting the active participation of senior management in support to structural, organizational and personal specialty. % Non-governmental paying sources: understanding that the health system is unique and that the private sector is part of the problem and solutions must be solved together. % Health professionals: recognizing the importance of teamwork, because while knowledge and individual clinical practice are important to a high quality health care system,


we now know that a professionals cannot practice a high quality Medicine working by themselves, even for good doctors. We can state that only the union of thoughts and objectives, beyond personal interests, can preserve, improve and transform our specialty.

REFERENCES 1. Stolf NA. Congenital heart surgery in a developing country: a few men for a great challenge. Circulation. 2007;116(17):1874-5.

2. Pinto Júnior VC, Daher CV, Sallum FS, Jatene MB, Croti UA. Situação das cirurgias cardíacas congênitas no Brasil. Rev Bras Cir Cardiovasc. 2004;19(2):III-VI. 3. Dearani JA, Neirotti R, Kohnke EJ, Sinha KK, Cabalka AK, Barnes RD, et al. Improving pediatric cardiac surgical care in developing countries: matching resources to needs. Semin Thorac Cardiovasc Surg Pediatr Card Surg Annu. 2010;13(1):35-43. 4. Leite DCF, Mendonça JT, Cipolotti R, Melo EV. Tratamento das cardiopatias congênitas em Sergipe: proposta de racionalização dos recursos para melhorar a assistência. Rev Bras Cir Cardiovasc. 2012;27(2):224-30.

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Editorial

The risk of risk scores and the dream of BraSCORE Omar Asdrúbal Vilca Mejía1, Luiz Augusto Ferreira Lisboa2

DOI: 10.5935/1678-9741.20120032

The risk scores are predictive tools that can help patients and health professionals in decision-making, the report on the likely risk of complications or death of groups of patients with similar risk profile and subjected to the same procedure. The existence of risk scores goes back to the Collaborative Study in Coronary Artery Surgery (1980), but what really sparked the creation and proliferation of risk scores was the publication by the Health Care Financing Administration (1986), the results without adjustment to the risk of mortality in Medicare hospitals in the United States. The advantage of the score is its practicality, because it expresses the overall risk of the patient, represented by the sum of the values assigned to each of the independent variables. In Brazil, Ribeiro et al. [1] brought in the same context, memories of a crude mortality, impossible to be accepted in modern cardiac surgery. Over time, the incorporation of the EuroSCORE [2] in the main services from Europe brought the sight of the Hawthorne effect, explaining that nothing has improved, neither the results of cardiac surgery at the beginning of the century, nor monitoring by the EuroSCORE. However, we must be careful in the incorporation of risk models, because we must respect the principles of statistical validation. Validating a model means to investigate the calibration and discrimination against a particular population under certain conditions. For this, the study variables must be defined similarly to those described by the model and the sample should include at least 100 deaths. The recording data should preferably be prospective and binding. In the validation, calibration evaluates the accuracy of the model to predict risk in a group of patients and discrimination measures the ability of the model to distinguish between patients at low and high risk. A suitable calibration and especially good discrimination are the basis

1. Doctor of Science (Cardiovascular Surgery), School of Medicine, University of São Paulo (USP), São Paulo, Brazil. 2. Professor in Cardiovascular Surgery FMUSP, São Paulo, Brazil.

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for a good performance of the model. So to have a model with high discriminatory power in general there must be many variables, bringing the risk of overfitting. Moreover, smaller models, but including such variables as those described by Jones et al. [3], tested by Tu et al. [4] and confirmed by Ranucci et al. [5], show good calibration, but unfortunately decreased the power of discrimination. Yet we must not forget that “fewer variables as possible” is better for a model. Another important characteristic for the incorporation of the model is that it must be comprehensive, therefore the methods are important. Among the techniques, the bootstrap is the most efficient way to find true independent predictors [6]. READ ORIGINALARTICLE ON PAGES 187-194 Clearly models derived risk and validated at a location usually have lower performance when applied at another location and even the same location over time. On this, Ivanov et al. [7] stated that in applying a risk score, it must first be remodeled (adaptation of the variables and their weights) or at least recalibrated (adjusting the weights of the variables) and never used the ready-made form (without adjustment of variables and their weights). Over time, the remodeling EuroSCORE would be necessary. That way, gave rise to the EuroSCORE II [8]. However, the concept of Ivanov took force when external models were applied locally and reshaped. Thus, Antunes Coimbra, followed by Billah, Australia, Shih, Taiwan, Berg, Norway, and Qadir, Pakistan, worked on this aspect. In Brazil, at the local level to merit the work of Cadore et al. [9] presented the first model for preoperative coronary surgery. At InCor-HCFMUSP remodeling all the model2000Bernstein EuroSCORE and Parsonnet, through the bootstrap technique gave the InsCor [10,11]. This model has similar performance to the EuroSCORE and was simpler than this and that-Parsonnet 2000Bernstein to predict mortality in patients undergoing coronary and / or valve at InCor (Figure 1).


But without doubt, the concept of BraSCORE ((Brazilian System for Cardiac Operative Risk Evaluation) goes further, will provide a predictive reference curve of the impact of the structure and resources available for programs on the results in morbidity and mortality of patients operated on cardiac surgery in Brazil. The BraSCORE will become the challenge to be overcome by teaching us the weaknesses of the practice. Thus, from the InsCor to the BraSCORE there is a long, but important, way to go. At the end, national or international reference, which will be easier, cheaper and appropriate?

evaluation (EuroSCORE). Eur J Cardiothorac Surg. 1999;16(1):9-13. 3. Jones RH, Hannan EL, Hammermeister KE, Delong ER, O’Connor GT, Luepker RV, et al. Identification of preoperative variables needed for risk adjustment of short-term mortality after coronary artery bypass graft surgery. The Working Group Panel on the Cooperative CABG Database Project. J Am Coll Cardiol. 1996;28(6):1478-87. 4. Tu JV, Sykora K, Naylor CD. Assessing the outcomes of coronary artery bypass graft surgery: how many risk factors are enough? Steering Committee of the Cardiac Care Network of Ontario. J Am Coll Cardiol. 1997;30(5):1317-23. 5. Ranucci M, Castelvecchio S, Conte M, Megliola G, Speziale G, Fiore F, et al. The easier, the better: age, creatinine, ejection fraction score for operative mortality risk stratification in a series of 29,659 patients undergoing elective cardiac surgery. J Thorac Cardiovasc Surg. 2011;142(3):581-6. 6. Austin PC, Tu JV. Bootstrap methods for developing predictive models. Am Stat. 2004;58(2):131-7. 7. Ivanov J, Tu JV, Naylor CD. Ready-made, recalibrated, or remodeled? Issues in the use of risk indexes for assessing mortality after coronary artery bypass graft surgery. Circulation. 1999;99(16):2098-104. 8. Nashef SA, Roques F, Sharples LD, Nilsson J, Smith C, Goldstone AR, et al. EuroSCORE II. Eur J Cardiothorac Surg. 2012;41(4):734-45.

Fig. 1 - ROC curve for InsCor (10 variables), the 2000BernsteinParsonnet (44 variables) and EuroSCORE (17 variables) in InCorHCFMUSP

REFERENCES 1. Ribeiro AL, Gagliardi SP, Nogueira JL, Silveira LM, Colosimo EA, Nascimento CAL. Mortality related to cardiac surgery in Brazil, 2000-2003. J Thorac Cardiovasc Surg. 2006;131(4):907-9. 2. Nashef SA, Roques F, Michel P, Gauducheau E, Lemeshow S, Salamon R. European system for cardiac operative risk

9. Cadore MP, Guaragna JCVC, Anacker JFA, Albuquerque LC, Bodanese LC, Piccoli JCE, et al. Proposição de um escore de risco cirúrgico em pacientes submetidos à cirurgia de revascularização miocárdica. Rev Bras Cir Cardiovasc. 2010;25(4):447-56. 10. Mejía OAV. Predição de mortalidade em cirurgia de coronária e/ ou valva no InCor: validação de dois modelos externos e comparação com o modelo desenvolvido localmente (InsCor) [Tese de doutoramento]. São Paulo: Faculdade de Medicina, Universidade de São Paulo; 2012. 11. Mejía OAV, Lisboa LAF, Dallan LAO, Pomerantzeff PMA, Moreira LFP, Jatene FB, Stolf NAG. Validação do 2000 Bernstein-Parsonnet e EuroSCORE no Instituto do CoraçãoUSP. Rev Bras Cir Cardiovasc. 2012;27(2):187-94.

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SOCIEDADE BRASILEIRA DE CIRURGIA CARDIOVASCULAR BRAZILIAN SOCIETY OF CARDIOVASCULAR SURGERY E-mail: revista@sbccv.org.br Sites: www.scielo.br/rbccv www.rbccv.org.br


ORIGINAL ARTICLE

Rev Bras Cir Cardiovasc 2012;27(2):187-94

Validation of The 2000 Bernstein-Parsonnet and Euroscore at the Heart Institute - USP Validação do 2000 Bernstein-Parsonnet e EuroSCORE no Instituto do Coração - USP

Omar Asdrúbal Vilca Mejía1, Luiz Augusto Ferreira Lisboa2, Luis Alberto Oliveira Dallan3, Pablo Maria Alberto Pomerantzeff4, Luiz Felipe Pinho Moreira5, Fabio Biscegli Jatene6, Noedir Antonio Groppo Stolf7

DOI: 10.5935/1678-9741.20120033

RBCCV 44205-1370

Abstract Objective: To validate the 2000 Bernstein Parsonnet (2000BP) and additive EuroSCORE (ES) to predict mortality in patients who underwent coronary bypass surgery and/or heart valve surgery at the Heart Institute, University of São Paulo (InCor/HC-FMUSP). Methods: A prospective observational design. We analyzed 3000 consecutive patients who underwent coronary bypass surgery and/or heart valve surgery, between May 2007 and July 2009 at the InCor/HC-FMUSP. Mortality was calculated with the 2000BP and ES models. The correlation between estimated mortality and observed mortality was validated by calibration and discrimination tests. Results: There were significant differences in the

prevalence of risk factors between the study population, 2000BP and ES. Patients were stratified into five groups for 2000BP and three for the ES. In the validation of models, the ES showed good calibration (P = 0.596), however, the 2000BP (P = 0.047) proved inadequate. In discrimination, the area under the ROC curve proved to be good for models, ES (0.79) and 2000BP (0.80). Conclusion: In the validation, 2000BP proved questionable and ES appropriate to predict mortality in patients who underwent coronary bypass surgery and/or heart valve surgery at the InCor/HC-FMUSP.

1. PhD in Sciences at Faculty of Faculty of Medicine of the University of São Paulo (FMUSP), São Paulo, SP, Brazil. 2. Full Professor, Physician assistant of the Coronary Heart Diseases Unit at Heart Institute of the Clinics Hospital, Faculty of Medicine, University of São Paulo (InCor/HC-FMUSP), São Paulo, SP, Brazil. 3. Full Professor, Associate Professor at FMUSP, Director of the Coronary Heart Diseases Unit of InCor/HC-FMUSP, São Paulo, SP, Brazil. 4. Full Professor, Associate Professor at FMUSP, Director of the Surgical Unit of Valve Diseases at InCor/HC-FMUSP, São Paulo, SP, Brazil. 5. Full Professor, Associate Professor at FMUSP, Director of the Research Surgical Unit at InCor/HC-FMUSP, São Paulo, SP, Brazil. 6. Titular Professor of the Thoracic Surgery Discipline at FMUSP, São Paulo, SP, Brazil. 7. Titular Professor of the Discipline of Cardiovascular Surgery at FMUSP, São Paulo, SP, Brazil.

This study was carried out at Heart Institute of the Clinics Hospital, Faculty of Medicine, University of São Paulo (InCor/HC-FMUSP), São Paulo, SP, Brazil.

Descriptors: Risk factors. Cardiovascular surgical procedures. Risk assessment. Hospital mortality. Validation studies.

Correspondence address Omar A. V. Mejía. Av. Dr. Enéas de Carvalho Aguiar, 44 – Cerqueira César – São Paulo, SP, Brazil – Zip Code 05403-000. E-mail: omarvilca@incor.usp.br

Support: National Council for Scientific and Technology Development

Article received on March 15th, 2012 Article accepted on May 2nd, 2012

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Abbreviations, Acronyms & Symbols 2000BP CAPPesq

2000 Bernstein Parsonnet Ethics Committee for Research Projects Analysis CRM CABG ES Aditive EuroSCORE InCor/HC-FMUSP Heart Institute, University of São Paulo

Resumo Objetivo: Validar o 2000 Bernstein Parsonnet (2000BP) e EuroSCORE aditivo (ES) na predição de mortalidade cirúrgica nos pacientes operados de coronária e/ou valva, no Instituto do Coração da Universidade de São Paulo (InCor/ HC-FMUSP). Métodos: Desenho prospectivo e observacional. Foram analisados, 3000 pacientes consecutivos operados de coronária e/ou valva, entre maio de 2007 e julho de 2009 no InCor/HC-FMUSP. A mortalidade foi calculada com os

INTRODUCTION Risk stratification informs patients and professionals about the likely risk of complications or death for the group of individuals with similar risk profile undergoing the proposed procedure [1]. However, in order to compare results using the same risk score, we would also have similar levels of accuracy and adequacy of the model in the populations studied [2]. Currently, the use of risk scores in decision making in coronary artery bypass surgery is considered IIa recommendation, with level of evidence B [3]. However, to be used, the risk models should be validated. Validating a model means investigating its calibration and discrimination in another population of which was developed [4]. The analysis of calibration requires that the use of the model is strict, without artificially increasing the weight of each variable, and the data is collected from all patients during a given period. Assessment of discrimination power requires no loss of outcome (death) in the calculations. The sample size and number of events are the most important aspects in the validation of a model, where at least 100 deaths should be considered [5]. Unfortunately, several studies performed in order to validate a score involving disabled people, 188

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escores 2000BP e ES. A correlação entre mortalidade estimada e mortalidade observada foi validada mediante testes de calibração e discriminação. Resultados: Houve diferença significativa na prevalência dos fatores de risco entre as populações do estudo, ES e 2000BP. Os pacientes foram estratificados em cinco grupos para o 2000BP e três para o ES. Na validação dos modelos, o ES apresentou uma boa calibração (P=0,596); no entanto, o 2000BP revelou-se inadequado (P=0,047). Na discriminação, a área abaixo da curva ROC revelou-se boa para ambos os modelos, ES (0,79) e 2000BP (0,80). Conclusão: Na validação, o 2000BP revelou-se questionável e o ES adequado para predizer mortalidade nos pacientes operados de coronária e/ou valva, no InCor/ HC-FMUSP.

Descritores: Fatores de risco. Procedimentos cirúrgicos cardiovasculares. Medição de risco. Mortalidade hospitalar. Estudos de validação.

making difficult the applicability of the models and therefore the interpretation of the results. In Brazil, no score predictor of mortality in cardiac surgery has been adequately validated, although several have already been used. Differences in clinical presentation due to socioeconomic, cultural and geographic reasons, unequal distribution of medical facilities, and high endemicity of subclinical inflammation, infection and rheumatic disease are evident, which could alter the performance of the models. For this, the EuroSCORE [6] and the 2000 Bernstein-Parsonnet [7] in several publications demonstrating its applicability in Brazil [8-11], were finally validated in patients undergoing coronary and/or valve surgery at the Heart Institute of the Clinics Hospital of Faculty of Medicine of the University of São Paulo (InCor/ HCFMUSP). METHODS Sample This prospective, observational study was performed at the Division of Cardiovascular Surgery, Department of Cardiology InCor/HCFMUSP. To calculate the sample size for validation of risk scores


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(minimum 100 deaths), the publication of Lisbon et al. [12] on the results of Incor-HCFMUSP in the past 23 years, reports an overall mortality of 6.9% and 4.8% for elective CABG and 8.4% for elective valve surgery. As in our study patients undergoing coronary and/or valve surgery were included, we considered reasonable to use lower mortality as a parameter, in this case the elective coronary surgery, resulting in a minimum sample size of 2084 patients.

model is well calibrated. The force calibration was assessed by testing the goodness of adjustment by the HosmerLemeshow test[13]. The P value > 0.05 indicates that the model fits the data and predicts mortality properly.

Inclusion and exclusion criteria Inclusion Criteria We included all consecutive patients who underwent surgery between May 2007 and July 2009, in the modality elective, urgent or emergency: • Valve surgery (replacement or repair); • coronary surgery (with or without the use of cardiopulmonary bypass); • Associated surgery (CABG and valve surgery). Exclusion Criteria Other types of associated surgery were excluded. Collecting, defining and organizing the data Data were collected preoperatively to clinical assessment and electronic medical records of the institution (SI3) and stored in a single spreadsheet. This spreadsheet has been adapted in order to include all the variables described by the model of the 2000 Bernstein Parsonnet and EuroSCORE. Sixty preoperative variables (demographic, clinical and laboratory) per patient were collected. All definitions assigned to variables for both scores were observed with their respective values, according to their relevance to the death event. Thus, after calculating the value of 2000BP and ES for each patient, they were ordered according to risk groups established by the scores and placed in the database made on Excel for this purpose. All patients were followed until hospital discharge. No patient was excluded from analysis due to missing data. The outcome of interest was in-hospital mortality, defined as death occurring in the time interval between surgery and discharge. Validation of the 2000 Bernstein Parsonnet and EuroSCORE To assess the performance of 2000BP and ES in predicting mortality, we performed a validation of predictive models in 3000 patients. The assessment was performed by testing calibration and discrimination. Calibration Calibration evaluates the accuracy of the model to predict risk in a group of patients. In other words, the model proposes that mortality in 1000 patients would be 5% and observed mortality is 5% or thereabouts, we say that the

Discrimination Discrimination measures the ability of the model to distinguish between patients at low and high risk. In other words, if the majority of deaths occurring in patients that the model identifies as high risk, we say that the model has good discrimination. Conversely, if the majority of deaths occurring in patients that the model identifies as low risk, we can say that the model has poor discrimination. The discrimination is measured by using the statistical technique called area under the ROC curve (sometimes called cstatistic-index or c). Thus, excellent discrimination refers to values above 0.97, very good discrimination is in the range from 0.93 to 0.96, good discrimination between 0.75 and 0.92; below corresponds to 0.75 models deficient in the ability of discrimination. [14] In practice, the models rarely exceed 0.85. Statistical analysis Statistical analysis was performed using SPSS software, version 16.0 for Windows (IBM Corporation Armonk, New York). Continuous variables were expressed as the mean ± standard deviation and categorical variables as percentages. The logistic regression analysis for the outcome of inhospital mortality was performed by using the value given to each patient by the 2000BP and ES scores. Calibration and discrimination were measured for each value of the score in the patient population. The performance of the models was also measured by comparing the observed mortality and expected mortality in risk groups established by the models. The Fisher exact test was used for contingency tables. The value of P <0.05 was considered significant. Ethics and Written Informed Consent This study was approved by the Ethics Committee for Research Projects Analysis (CAPPesq), Clinics Hospital, University of São Paulo, under number 1575. RESULTS Casuistry All patients undergoing coronary and/or valve surgery, between May 2007 and July 2009, at InCor/HCFMUSP, were included in the study. Of the 3000 patients who underwent surgery, 268 (8.9%) died. Of the total procedures, 57.7% (1731) underwent surgery for coronary, 36.8% (1104), valve and 5.5% (165), coronary and valve. For descriptive purpose, we show in Table 1 the 189


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prevalence of risk factors in the study population and the population of the ES. Similarly, Table 2 shows the prevalence of risk factors in the study population and the population of 2000BP. Because these populations are potentially comparable, we assessed the statistical difference in the prevalence of risk factors in ES and 2000BP, with respect to the study population.

Outcomes of 2000 Bernstein Parsonnet and EuroSCORE validation. Calibration Results 2000 Bernstein Parsonnet Association was found between model 2000BP and death with OR: 1.079 (P <0.001). The Hosmer-Lemeshow test showed a goodness-of-fit statistic = 15.678 with 8 degrees of freedom, P = 0.0472 (Table 3). For a better suitability analysis, the 2000BP was divided into five categories (Table 4). The 2000BP shows a poor fit in the subgroups established.

Table 1. Prevalence of risk factors in the study group comparing the risk factors of the EuroSCORE population. VARIABLES P STUDY EuroSCORE Age (N=3000) (N=19030) <60 years 44.27% 33.20% < 0.001 60-64 years 0.007 15.80% 17.80% 65-69 years 13.87% 20.70% < 0.001 70-74 years 12.20% 17.90% < 0.001 >75 years 0.001 11.50% 9.60% Female 35.90% 27.80% < 0.001 Chronic lung disease < 0.001 2.60% 3.90% Extracardiac arteriopathy 4.80% 11.30% < 0.001 Neurological dysfunction < 0.001 6.90% 1.40% < 0.001 Previous cardiac surgery 17.80% 7.30% Creatinine > 2,3 mg/dl < 0.001 4.40% 1.80% < 0.001 Active endocarditis 4.10% 1.00% Critical preoperative state < 0.001 10.30% 4.10% 0.059 Unstable angina 7.00% 8.00% EF 30 – 50 0.569 26.10% 25.60% 0.998 EF <30 5.80% 5.80% Recent AMI < 0.001 16.80% 9.70% < 0.001 Pulmonary hypertension 8.10% 2.00% Emergency < 0.001 3.10% 4.90% Combined surgery 6.90% 36.40% < 0.001 Thoracic aortic surgery < 0.001 0.70% 2.40% 0.002 Postinfarction VSD 0.50% 0.20% EF = ejection fraction; AMI = acute myocardial infarction; CIV = interventricular communication

Table 2. Prevalence of risk factors in the study group comparing the risk factors of the 2000 Bernstein Parsonnet population. VARIABLES P STUDY 2000BP Age (N=3000) (N=10703) 70-74 years 12.20% 18.50% < 0.001 >75 years 0.002 11.50% 13.70% Female 35.90% 31.30% < 0.001 Chronic lung disease 2.60% 10.80% < 0.001 Extracardiac arteriopathy < 0.001 4.80% 9.10% Neurological dysfunction 0.008 6.90% 8.40% < 0.001 Previous cardiac surgery 17.80% 7.60% Creatinine > 2,3 mg/dl 4.40% 0.809 4.50% EF 30 – 50 26.10% 38.60% < 0.001 EF <30 < 0.001 5.80% 8.40% Pulmonary hypertension 8.10% 10.70% < 0.001 EF = ejection fraction

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EuroSCORE Association was found between ES model and death with OR: 1.337 (P <0.001). The Hosmer-Lemeshow test showed a goodness-of-fit-statistic = 5.5301, with 7 degrees of freedom, P = 0.5956 (Table 5). For a better suitability analysis, the ES was divided into three categories (Table 6). The ES presents an appropriate fit in the subgroups established.

Table 3. Observed and expected mortality by use of 2000BP as predictor variable in the groups defined by the HosmerLemeshow test. DEATH=1 DEATH=0 Group Total Observed Expected Observed Expected 287 5.42 287.58 1 293 6 7.43 297 293.57 2 301 4 9.17 297 290.83 3 300 3 10.82 280 281.18 4 292 12 266 12.15 259.85 5 272 6 274 15.52 270.48 6 286 12 20.97 274 278.03 7 299 25 27.90 263 268.10 8 296 33 244 43.60 255.40 9 299 55 249 116.03 245.97 10 362 113 * Goodness of fit statistic = 15.678 with 8 DF (P=0.0472)

Table 4. Percentages of observed and estimated mortality by 2000BP risk group. Risk EM OM N % OM/EM 19.8 <9 0.77 2.19 1.68 594 9-14 0.75 3.38 2.53 592 19.7 18.6 14.1-19.9 0.67 4.84 3.23 558 20-28.9 1.18 8.24 9.75 595 19.8 > 29 1.05 24.21 25.42 661 22 OM / EM = Observed Mortality/Expected Mortality, EM = expected mortality, OM = observed mortality; N = Number of patients; % = Percentage


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Table 5. Observed and expected mortality by use of ES as a predictor variable in the groups defined by the Hosmer – Lemeshow test. DEATH=1 DEATH=0 Group Total Observed Expected Observed Expected 5 296 1 4.83 291.17 291 10 378 2 8.20 369.80 368 6 287 3 8.27 281 278.73 12 397 4 15.15 381.85 385 19 358 5 18.04 339.96 339 14 269 6 17.83 255 251.17 19 264 7 22.89 241.11 245 53 345 8 43.97 292 301.03 131 406 9 129.83 276.17 275

Table 7. Area under the ROC curve for the 2000BP and ES from the analysis performed in 3000 patients. Area CI 95% ep P 2000BP 0.800 0.772 – 0.827 0.014 < 0.001 ES 0.796 0.766 – 0.826 0.015 < 0.001

EuroSCORE Assessing the discriminative power of ES, we observe that the area under the ROC curve was 0.796 (95% CI, 0.766 to 0.826, P=0.015) (Table 7).

* Goodness of fit statistic = 5.5301 com 7 DF (P=0.5956)

DISCUSSION Table 6. Percentages of observed and estimated mortality by risk groups of ES. EM OM N % Risc OM/EM 0–2 1 2.19 2.19 961 32.03 3–5 0.88 4.98 4.39 1024 34.13 >6 1.03 19.41 20.00 1015 33.83 OM / EM = Observed Mortality/Expected Mortality, EM = expected mortality, OM = observed mortality; N = Number of patients; % = Percentage

Outcomes of Discrimination (ROC curves, Figure 1). 2000 Bernstein Parsonnet Assessing the discriminative power of 2000BP, we observe that the area under the ROC curve was 0.800 (95% CI, 0.772 to 0.827, P=0.014) (Table 7).

Fig 1 - ROC curve for 2000BP and ES in assessing the power of discrimination performed in 3000 patients. 2000BP ROC ROC curve = 2000 presented by Bernstein Parsonnet score, ES ROC = ROC curve resulting from the EuroSCORE

Only predictive models consisting of preoperative variables can be used in making decisions, by not including variables per and/or postoperative. Thus, several publications for the use of 2000BP and ES models in predicting mortality in cardiac surgery, even in our country [8], consolidated the importance of these models. One of the first analysis was published in Saudi Arabia in 2004 by Syed et al. [15] comparing the ES model with the initial Parsonnet, in 194 patients. The areas under the ROC curve were 0.77 for the ES model and 0.69 for the initial Parsonnet. However, the sample size, with only 13 deaths loses in credibility and statistical power. In the same year, an assessment made in Taiwan by Chen et al. [16] used the ES in 801 consecutive patients with coronary artery bypass graft (CABG). With just over 80 deaths, the area under the ROC curve reached 0.75. One of the best study was performed by Berman et al. [17] in Israel in 2006. The 2000BP was compared to ES. They assessed 1639 consecutive patients with coronary and/or valve disease. The area under the ROC curve was 0.83 for 2000BP and 0.73 for the ES. This result was similar to our initial analysis performed in InCor/HCFMUSP [8] in 744 patients using the same risk scores. In this analysis, the Hosmer-Lemeshow test for 2000BP (P = 0.70) and the ES (P = 0.39) indicated good calibration. Also, the ROC curve for the 2000BP = 0.84 and = 0.81 for the ES was suitable for predicting mortality. However, the interpretation of model validation was limited by the number of deaths. In the final analysis, with 3000 patients, we can see that for this sample size the calibration is reversed, the 2000BP no longer calibrates (P = 0.047) and ES increases its calibration (P = 0.597). However, good discrimination persists with an area under the ROC curve of 0.80 for ES and 0.81 for 2000BP. In this context, the literature shows that the origin, nature and evolution of these models are in favor of better performance of ES in larger populations, while the 2000BP makes smaller groups. One explanation for this is known in 191


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statistics as overfitting of the models when presenting many variables [5.18]. This was confirmed by an analysis of 1000 patients in the same sample, where 2000BP presented a calibration with P = 0.157 and P = 0.593 with ES (unpublished data). Therefore, since the sample size increases, the calibration of ES improves, and the 2000BP, worsens. Thus, we recommend that in the calibration, the 2000BP is chosen to populations up to 744 patients, and from that, the ES is preferred. Even then, the persistence of discrimination adequate for both models indicates that the variables contained in the models are true predictors of mortality [19]. One of the first studies performed in Brazil, Pernambuco, is authored by Moraes et al. [9] who in 2006, retrospectively assessed the applicability of the ES in 752 patients undergoing CABG. With only 13 deaths, the sample had an area under the ROC curve of 0.70, lower than that found in our study, which also assessed valve and associated surgery. In 2008, Campagnucci et al. [10] published in Brazil, a retrospective analysis with ES in 100 consecutive patients undergoing CABG. The sample size limited the statistical analysis, hampering proper conclusion of the study. In 2009, Ranucci et al. [18] published in Italy, an analysis of 11,150 patients undergoing cardiac surgery, demonstrating that limiting the number of variables used by EuroSCORE would decrease the risk of overfitting, multicollinearity and human error. The best accuracy was obtained with five variables (age, ejection fraction, creatinine, emergency surgery and CABG combined), with an area under the ROC curve of 0.76 compared to 0.75 of the logistic EuroSCORE. In this study it was shown that models of few variables, but with strong association with mortality, could provide good calibration, obviously the expense of proper discrimination. In 2010, Malik et al. [20] published in India, the validation of the ES in 1000 consecutive patients after cardiac surgery. The area under the ROC curve was 0.827. In calibration, the Hosmer-Lemeshow test showed P = 0.73. The difference in the clinical profile of patients between both populations was marked by a high prevalence of variables associated with late presentation of the disease. The data from this analysis are very similar to those of our study, both in methodology, results and prevalence of risk factors. In March 2011, Shih et al. [21] published in Taiwan, the performance of the ES in 1240 patients undergoing cardiac surgery. The area under the ROC curve was 0.839. In calibration, all subgroups except for CABG, demonstrated good application of the model. A study published in Pakistan in April 2011, by Qadir et al. [22] retrospectively assessed the ES in 2004 patients undergoing CABG. The area under the ROC curve was 0.866. In calibration, it was yielded a P value = 0.424. The model overestimated mortality in the group of low and medium risk. Currently, the use of risk scores is made preoperatively,

to aid in making decisions (questionable in indicating new technologies) and postoperatively, for the prevention of adverse effects and cost control, mainly in intensive care unit. It is logical to think that, in time and space, variations in the systems of prevention, diagnosis and treatment of risk factors can alter the accuracy of the models. Thus, in order to use these mathematical models, we must first validate them with the principles of proper statistical analysis. In our reality, the lack of proper validation of external models, required in developing a population with high prevalence of rheumatic disease and Chagas, was impairing the knowlegement about the risk assessment of patients undergoing cardiac surgery in Brazil. As can be evidenced in Tables 2 and 3, in most validation studies, there is a significant difference in the prevalence of risk factors between the study population and the populations of the analyzed models. Even so, the appropriate application (respecting the statistical principles) for accurate risk models consisting of variables strongly predictive of mortality can succeed. Certainly, the fact of recalibrating the model (adapting the weights of the variables according to their importance in the study population), or better yet, reshaping the model (adding new variables related to mortality or removing variables that may hinder the stability of the model), would lead to a more sophisticated and accurate for the population under study, with larger areas under the ROC curve [23]. A Brazilian model (even without external validation), published in 2010 by Cadore et al. [24], in Rio Grande do Sul, brings a proposal for a local model to predict outcomes in coronary artery bypass surgery. This model demonstrates a practical and simple good area under the ROC curve of 0.86. However, it is derived from a retrospective database of patients who have undergone surgery in 1996-2007 (> 5 years) and that with a mortality of 10% could overestimate results. In 2010, SĂĄ et al. [11] published in Pernambuco, a retrospective analysis of 500 patients on the ES, including 65 deaths. In addition to the limited number of events in the study, difficulty in defining and collecting data for the retrospective nature of the analysis, may have hindered the allocation of patients to the risk group established by ES. In our study, the mortality of 20% (including coronary and/or valve surgery) in high-risk patients was similar to that expected of 19.41%, even though between 75 and 80% of patients who have undergone surgery at InCor/ HCFMUSP are served by the Unified Health System (SUS). This high mortality was confirmed by ES, considering the high prevalence of risk factors in this group of patients. Therefore, controlling and decreasing the prevalence of risk factors result in lower values of observed mortality. Moreover, for the calibration of the models, it is

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recommended to use the Hosmer-Lemeshow test. The Kappa index depends on the prevalence of the disease under study. A high prevalence results in high level of agreement expected by chance, resulting in lower k value. Therefore, we may make the mistake of basing this index on a comparison of two studies with different prevalences. Limitations of this study were: first, although as unicentric, the most important limitation is the generalizability of the results, about 50% of patients attending the hospital are from different states of Brazil. Secondly, because of its nature, the additive EuroSCORE tends to underestimate risk in high-risk patients, although this has not been shown in multicenter studies [25]. Finally, although hospital mortality (up to 30 days after surgery) appears to be more complete than the in-hospital mortality, the current definitions suggest that both have equivalent accuracy, and in-hospital mortality was more practical and easy to use [26]. Thus, also the advances in perioperative care in cardiac surgery could be better assessed with the remodeled EuroSCORE (EuroSCORE II) [27], especially in places where the EuroSCORE lost calibration. But even so, we should be careful about the limitations of the new model, because it was the inappropriate use of the first version which led to a dramatic expansion of the market for transcatheter aortic valve implantation. Finally, it is important to clarify that the scores assess only a tiny part of the multiple variables known and unknown to the patient and the health care structure, which directly influence the outcome of the process. Therefore, the conclusions derived from its application must be carefully assessed.

3. Hillis LD, Smith PK, Anderson JL, Bittl JA, Bridges CR, Byrne JG, et al. 2011 ACCF/AHA guideline for coronary artery bypass graft surgery: executive summary: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. J Thorac Cardiovasc Surg. 2012;143(1):4-34.

CONCLUSIONS The 2000 Bernstein Parsonnet proved to be poor in calibration and good discrimination, being questionable in validating to predict mortality in patients undergoing coronary and/or valve surgery at InCor/HCFMUSP. The EuroSCORE proved to good both in calibration and discrimination, with appropriate validation to predict mortality in patients undergoing coronary and or valve surgery in InCor/HCFMUSP.

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20. Malik M, Chauhan S, Malik V, Gharde P, Kiran U, Pandey RM. Is EuroSCORE applicable to Indian patients undergoing cardiac surgery? Ann Card Anaesth. 2010;13(3):241-5. 21. Shih HH, Kang PL, Pan JY, Wu TH, Wu CT, Lin CY, et al. Performance of European system for cardiac operative risk evaluation in Veterans General Hospital Kaohsiung cardiac surgery. J Chin Med Assoc. 2011;4(3):115-20. 22. Qadir I, Perveen S, Furnaz S, Shahabuddin S, Sharif H. Risk

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ORIGINAL ARTICLE

Rev Bras Cir Cardiovasc 2012;27(2):195-202

Comparison of electrophysiological parameters of septal and apical endocardial cardiac stimulation Comparação de parâmetros eletrofisiológicos das estimulações cardíacas endocárdicas septal e apical

Juan Carlos Pachón Mateos1, José Carlos Pachón Mateos2, Remy Nelson Albornoz Vargas1, Enrique Indalécio Pachón Mateos1, Khalil Cosac1, Hugo Belloti Lopes1, Fabrizio Achilles Soares1, Amanda Guerra Moraes Rego Sousa3

DOI: 10.5935/1678-9741.20120055

RBCCV 44205-1371

Abstract Background: The conventional right ventricle (RV) endocardial pacing leads QRS widening and myocardial desynchronization compromising ventricular function. With the need for less deleterious stimulation, RV septal pacing has been used more. Eventually have been reported higher thresholds and smaller R waves in the septal stimulation. Objective: To compare the parameters of the septal and apical stimulation, intra-patient, if there are any differences that may affect the choice of the point of stimulation. Methods: A prospective controlled study. We included 25 patients, 67.2±9 years, 10 (40%) women with indications for pacemaker for bradyarrhythmias. Etiologies were degenerative in nine (36%), Coronary disease in eight (32%), Chagas disease in seven (28%), and valve disease in one (4%) patient. Electrodes were active fixation and assessed the thresholds of command, impedance and R wave in uniand bipolar implant and after six months.

Results: The average acute threshold command, R wave and impedance unipolar / bipolar septais x apicais were respectively 0.73 x 0.73V and 0,74V x 0,78V; 10 x 9,9mV and Ω and 611 x 629Ω Ω. Comparisons 12,3 x 12,4mV; 579 x 621Ω between parameters with septal and apical two-tailed paired t-test showed a P > 0.1. After six months, the mean control thresholds, R wave impedances and unipolar/bipolar septais x apicais were respectively 0.5V x 0 72V and 0.71V x 0,87V; 11.4 x 9,5mV and 12x11,2mV; 423x426 Ω and 578x550 Ω, with P > 0.05, except compared to unipolar pacing threshold septal apical unipolar P 0.02. Conclusion: Using intra-patient comparisons, no significant differences between electrophysiological parameters septal and apical pacing and there are no restrictions for choosing the right ventricular septal pacing.

1. Physician at Dante Pazzanese Cardiology Institute, São Paulo, SP, Brazil. 2. Director of the Pacing Service at Dante Pazzanese Cardiology Institute, São Paulo, SP, Brazil. 3. Director at Dante Pazzanese Cardiology Institute, São Paulo, SP, Brazil.

Correspondence address: Juan Carlos Pachón Mateos Rua Doutor Dante Pazzanese, 500 – Vila Mariana – São Paulo, SP, Brazil – Zip Code: 04012-909 E-mail: juanpachon@gmail.com

This study was carried out at Dante Pazzanese Cardiologiy Institute São Paulo, SP, Brazil.

Article received on June 7th, 2012 Article accepted on June 17th, 2012

Descriptors: Pacemaker, artificial. Bradycardia. Cardiac resynchronization therapy.

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Abbreviations, acronyms & symbols AV block Complete AV block DECA

SND AF EF CAD NYHA RV SOBRAC

LV

Atrioventricular block Complete atrioventricular block Departamento de Estimulação Cardíaca Artificial [Artificial Heart Stimulation Department] Sinus Node dysfunction Atrial Fibrillation Ejection Fraction Coronary Artery Disease New York Heart Association Right Ventricle Sociedade Brasileira de Arritmias Cardíacas [Brazilian Society of Cardiac Arrhythmias] Left Ventricle

Resumo Fundamento: A estimulação endocárdica convencional do ventrículo direito (VD) ocasiona alargamento do QRS e dessincronização do miocárdio, comprometendo a função ventricular. Com a necessidade de estimulação menos deletéria, a estimulação septal do VD tem sido mais utilizada. Eventualmente têm sido relatados limiares mais altos e ondas R menores na estimulação septal. Objetivo: Comparar os parâmetros das estimulações apical e septal, intrapaciente, para verificar se existem diferenças

INTRODUCTION The normal QRS duration is < 120 ms owing to the very rapid ventricular activation mediated by the His-Purkinje system and by the subendocardial branches of Purkinje. This organized activation also determines the location of the normal QRS axis to the left (between -30 and +90 degrees) and backwards, pointing to the left ventricle (LV) due to its electrical predominance. Apart from speed and synchronism, the normal course of the cardiac conduction favors the optimum maintenance of the intramyocardial tensions. These benefits are lost when the QRS widens, which results in significant damage of the cardiac function [1-3]. The wide QRS (mainly with morphology of left bundle branch block-LBBB) promotes ventricular desynchronization. Thus, while part of the cells is contracting the other part is still relaxing, blunting the increase in intraventricular pressure which creates a high preload in lately activated cells. Eventually, the desynchronized activation of the papillary muscles worsens or even provokes mitral regurgitation. These abnormalities result in significant loss of ventricular effectiveness, especially in cases with cardiomyopathy. The conventional cardiac pacemaker with the implanted 196

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que possam interferir na escolha do ponto de estimulação. Métodos: Estudo prospectivo controlado. Foram incluídos 25 pacientes, com 67,2 ± 9 anos, 10 (40%) mulheres, com indicações de marca-passo por bradiarritmias. Etiologias foram degenerativa em nove (36%), coronariopatia em oito (32%), doença de Chagas em sete (28%), e valvopatia em um (4%) pacientes. Foram utilizados eletrodos de fixação ativa e avaliados os limiares de comando, impedância e onda R uni e bipolares no implante e após seis meses. Resultados: A média aguda dos limiares de comando, ondas R e impedâncias unipolares/bipolares septais x apicais foram, respectivamente, 0,73x0,74V e 0,73x0,78V; 10x9,9 mV e 12,3x12,4 mV; 579x621 Ω e 611x629 Ω . Comparações entre parâmetros septais e apicais com teste t-pareado bicaudal demonstraram um P > 0,1. Após seis meses, a média dos limiares de comando, ondas R e Impedâncias unipolares/ bipolares septais x apicais foram, respectivamente, 0,5 x 0,72 Ωe V e 0,71 x 0,87 V; 11,4x9,5 mV e 12x11,2 mV; 423x426Ω Ω, com P > 0,05, exceto comparando-se limiar de 578x550Ω estimulação unipolar septal com apical unipolar p de 0,02. Conclusão: Utilizando comparações intrapaciente, não existem diferenças expressivas entre parâmetros eletrofisiológicos de estimulação septal e apical sendo que não há restrições para a escolha da estimulação septal em ventrículo direito. Descritores: Marca-Passo artificial. Bradicardia. Terapia de ressincronização cardíaca.

lead in the right ventricle (RV) apex promotes an important widening of the QRS which is similar in morphology and mechanical dyssynchrony to the one caused by LBBB [46]. This phenomenon is an important factor which promotes an unwanted ventricular remodeling [7-9]. Great progress has been achieved to prevent, correct or reduce the ventricular desynchronization, such as biventricular (BiV) pacing [10,11] or the bifocal right ventricular pacing [12,13] which depend on placement of one more ventricular lead. Septal pacing has been widely used in the search for a less deleterious right ventricular pacing, but preliminary data have possibly shown isolated cases with higher thresholds and shorter R waves. Primary Endpoint To compare apical and septal pacing during acute and chronic phases in the same patient. It aims to identify any significant differences in threshold, R wave and impedance which may reject or recommend any pacing point. Secondary Endpoints 1. To compare the QRS durations originated by septal and apical pacing; 2. To check if the QRS axis is more or less physiological


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(between -30 degrees and +90 degrees) in septal pacing in relation to apical pacing; 3. To evaluate the stability of the septal lead and the risk of displacement.

In order to access the high septum, it was used a manual modeling of a steel guide in two planes, so that it could be directed to the high portions with its tip turned backwards. This position was confirmed by radioscopy in left anterior oblique position (Figure 1), aiming to prevent unintended and unwanted implantation into the RV free wall. It was used endocardial leads from three manufacturers with the following features: active fixation by screw-in, narrow diameter, short distance between the poles and similar impedances. Biotronik DR Philos II and Entovis were used because they were the only pacemakers allowing programming to a DVIR mode with an very short AV interval of 15 ms. These resources are indispensable for the RV bifocal pacing, since it allows virtually simultaneous activation of the two points being the high septum 15 ms prior to the RV apex. Additionally this mode of pacing enables a noninvasive and independent programming of the two points, at any stage of the follow-up. Unipolar and bipolar parameters - threshold, R wave and impedance - in both positions were evaluated by Biotronik ICS-300 system during the implantation and six months later by telemetry. The12-lead electrocardiograms (EKG) were recorded by the TEB ECG PC computerized electrocardiograph.

METHODS The features of the patients of this trial are summarized in Table 1. The pacemakers indications were determined according to SOBRAC-DECA and American Heart Association [14] guidelines. Implantation Technique In each patient two leads were intravenously implanted, one in the RV apex, in the classical position of the conventional endocardial pacing, and another in high portions of the intraventricular septum next to His Bundle, called septal in this trial, searching for the best command and sensitivity parameters. The lead was placed in high, mid-septal or para-Hisian region, and that of narrower QRS was chosen. The endocardial injury current in endocavitary electrogram was registered and evaluated in both septal and apical implantations, searching for a good myocardial viability and for the best placement of the lead.

Table 1. Basic patients features. Feature Male Female Age Etiology Chagas Disease SND CAD Valvar pathology Pacemaker Indication AF + High Degree AV block AF + complete AV block EF (%) Functional class (NYHA) II III IV Paced QRS duration (ms) Paced QRS axis (degrees) Pacemaker Philos II DR Pacemaker Entovis DR

N or Mean 15 10 67,2 ± 8,8

Interval __ 44 to 81

7 9 8 1

% 60 40 28 36 32 4

21 4 36 ± 6 2,8 ± 0,4 4 20 1 134 ± 19 45 ± 73,8 20 5

84 16 16 80 4 80 20

__ __ 21 to 48 II to IV __ __ __ 90 to 160 -150 to +135 __ __

__ __ __ __

NYHA = New York Heart Association, AV block = atrioventricular block, complete AV block = complete atrioventricular block; CAD = coronary artery disease; AF = atrial fibrillation; EF = ejection fraction; SND = sinus node dysfuntion

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Fig. 1 – Chest X-ray (CXR) in PA and in left anterior oblique (LAO) position, showing the final position of the implanted leads into the RV apex (A) and into RV septal region (S). It is observed that in LAO position the septal lead is fully geared to the vertebral column, opposite to the RV free wall of

Table 2. Means of the measures of the thresholds, R wave and impedances, unipolar and bipolar in acute phase (implantation) and chronic phase (six months later) with two-tailed p-value t-test. Acute Chronic Threshold R Impedance Threshold R Impedance Uni Bi Uni Bi Uni Bi Uni Bi Uni Bi Uni Bi Septal 0.73 0.73 10.0 12.3 579 611 0.5 0.71 11.4 11.2 423 578 Apical 0.74 0.78 9.9 12.4 621 629 0.72 0.87 9.5 12.0 426 550 P 0.17 0.39 0.8 0.93 0.09 0.34 0.02 0.12 0.09 0.5 0.8 0.24

During the follow-up all the patients were kept with RV bifocal pacing as this stimulation was the one with the narrower paced QRS. The patients were observed for 60 days to check possible complications associated with the implantation.

paired t test. The differences with P value < 0.05 were considered significant. Informed consent was obtained from all patients for pacemaker and lead implantation and for all the measurements during the follow-up. RESULTS

Statistical Analysis and Informed Consent Data were inserted on Excel-2010 spreadsheet and means, standard deviation, maximum and minimum values, confidence intervals as well as median were established. The continuous variables were evaluated by two-tailed

Table 3. Comparison of the QRS duration under apical and septal RV pacing. Even though it is not the aim of this study, QRS duration of bifocal pacing was also compared, since it provided the narrower paced QRS and was chosen as the background pacing method in these patients. Mean ±SD Interval P (ms) (ms) Apical QRS 192.5 ± 18.9 160 to 227 < 0.01 Septal QRS 164 ± 13.3 140 to 187 < 0.01 < 0.01 Bifocal QRS 152.7 ± 16.9 107 to 177

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The pacing thresholds, R wave and impedances unipolar and bipolar, acute and chronic at the sixth month of followup are shown in Table 2. The means of septal and apical values unipolar and bipolar were very similar without significant statistical difference (P ≥ 0.09) except when comparing unipolar thresholds in chronic phase, in which the mean of unipolar ones was slightly lower in septal pacing than in apical pacing, 0.5Vx 0.72V, (P=0.02). Table 3 shows the comparisons of QRS duration obtained from the 12-lead ECG in the chronic phase, in apical and septal pacing. The mean of QRS duration obtained by septal pacing was clearly lower than the mean of QRS duration of apical pacing with highly significant difference (P<0.01). Incidentally, were observed that the mean of QRS


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duration obtained by RV bifocal pacing (being septum 15 ms before apex) was even lower. In terms of the QRS axis there was a clear tendency of keeping the axis inside the normal limits under septal pacing, while the apical pacing caused complete non-physiological QRS axis, (Table 4). This difference was statistically very significant.

Problems of RV Apical Pacing Ventricular endocardial pacing in the RV apex (apical) is broadly used worldwide since the Sixties’ and is the most widespread method of artificial cardiac pacing. However, although it has been revolutionary, safe and efficient to correct bradyarrhythmias, it induces a functional left branch block and promotes a serious desynchrony of the LV walls [15]. This undesirable “side effect” may cause or even worsen the HF, whose symptoms may not be completely taken into account since they are blunted by the increase in the cardiac output obtained by the bradyarrhythmia correction. However, if sustained , this condition promotes an undesirable myocardial remodeling which predisposes the patient to the appearance or worsening the HF, reduces the quality of life and leads to an increase in mortality, even in normal functioning AV sequential pacemakers [16]. In addition, several multi-center randomized trials have shown valuable information of the RV apical pacing damage, although they have been intended for another objective. MOST [17], DAVID [18] and MADIT-II [18] trials showed that the longer the time of RV apical pacing, the higher the HF, hospitalization, atrial fibrillation (AF), ventricular arrhythmias and mortality incidence. These considerations make us to conclude that regardless these problems the RV endocardial pacing is the most frequently used treatment for bradyarrhythmias, although it causes several and unwanted consequences such as: • Structural and histological remodeling of the myocardium • Favors the AF • Promotes or increases mitral regurgitation • Promotes myocardial dysfunction • Favors the HF progression • Reduces quality of life • Increases mortality

Table 4. Comparison with the QRS axis obtained in chronic phase with apical and septal pacing in right ventricle. Although it have been not the aim of this study, QRS axis of bifocal pacing was also compared, considering that it was the final stimulation mode since as it showed the narrowest QRS. Mean±SD (degrees) Apical QRS axis -68.4 ± 20.3 Septal QRS axis 79.8 ± 43.4 Bifocal QRS axis 44.2 ± 87.2

Interval P (degrees) -120 to -30 < 0.01 -60 to 135 < 0.01 < 0.01 165 to 150

Although being not the objective of the study, bifocal QRS axis were measured to determine the best method to stimulate the enrolled patients. Complications There was one lead displacement from the septal position and one hematoma caused by the oral anticoagulant use as these patients presented permanent atrial fibrillation. The lead was replaced with one with longer screw-in system and the hematoma was easily solved with surgical repair before the hospital discharge. DISCUSSION Many patients who suffer from heart failure (HF) due to dilated cardiomyopathy (DCM) show bradyarrhythmia with cardiac pacemaker indication. However, classical ventricular pacing of the RV apex with wide QRS causes systolic and diastolic function impairment, besides mitral regurgitation [7]. Consequently, although the bradyarrhythmia be solved, the classical (apical) pacing worsens or even triggers HF. The functional impairment is even greater in patients with cardiomyopathy who are long-term pacemaker dependent and usually show widen QRS such as LBBB, reaching even more than 250 ms. The same unwanted hemodynamic phenomenon is observed in spontaneous complete left branch block. Actually, the classical pacing is deleterious for the myocardium and it is even used in hypertrophic obstructive cardiomyopathy, situation in which the functional impairment reflects on the desired reduction of the intraventricular gradient.

Fig. 2- Schemashowing several alternative positions for RV pacing. His Bundle pacing would be the ideal method in all the cases with previous narrow QRS. However, some limitations prevent it from being currently used

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Alternative Pacing of the RV with one lead Several areas of the RV may be safely stimulated by using modern active fixation leads (Figure 2). In an experimental trial comparing the hemodynamic result of different points of pacing in the RV [19], His Bundle pacing showed the best result as expected. However, the most important observation is that the worst outcomes were obtained from the RV apical pacing, namely conventional stimulation. Although the stimulation of the His Bundle is more physiological and enables the maximum resynchronization with normal QRS which prevents the impairment of systolic and diastolic functions and mitral regurgitation, there are practical limitations which have been hindering its common use, such as: it is technically more difficult; it has higher thresholds; it needs special leads and introducers; it is susceptible to oversensing of atrial far-field and it may not be recommended in cases of previous His-Purkinje system lesions. Considering the problems of apical pacing and to the limitations of currently using the His Bundle pacing it makes sense to pay greater attention to the septal pacing. lead, Modern active-fixation electrodes have low profile and are highly flexible which makes it relatively easy to lead the implantation by using the pre-shaped guide-wire to the midseptal or para-Hisian region. The electrocardiographic benefit is usually the first consequence observed during the pacemaker implant: the narrower QRS and the QRS axis closer to normal condition (positive or isodiphasic QRS in D1 and positive in D2, D3 and aVF). In addition, there is a

Fig.. 3- Prevention of the histological remodeling of the myocardium of the LV by means of the septal pacing of the RV (Karpawich e al. [20])

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significant echocardiographic improvement followed by clinical benefit that is usually reflected bythe reduction of the quality of life score.. These findings are strengthened by the experimental study of Karpawich et al. [20] who obtained great histological benefit from septal pacing in relation to apical pacing. They showed a very significant and udesirable histological remodeling by RV apical pacing that was prevented by the RV septal pacing (Figure 3). Implantation Technique and Complications Although it depends on a more accurate surgical procedure, no significant difficulty with the septal implantation or to para-Hisian implantation was observed since the technique and the radiological confirmation are taken into account during the lead placement. In general, the implantation was fast which did not increase the risk of infection and of radiological exposure. One case of generator pocket hematoma caused by the chronic use of oral anticoagulants was observed. It was completely solved by surgical drainage before the hospital discharge. The sole complication directly associated with the septal implantation was an acute dislodgement which was corrected by lead repositioning during the same hospitalization. This fact deserves additional comments since they were associated with the use of an endocardial active fixation lead with a short screw. After this observation, this kind of lead was changed and only a model with longer fixation screw started to be used. Threshold The means of the unipolar and bipolar septal thresholds were 6.8% lower than the means of the unipolar and bipolar apical thresholds in the acute phase, but there was no statistically significant difference (P = 0.17 and 0.39 [twotailed paired t test] respectively) (Table 2). In the chronic phase (six months later), the means of the unipolar and bipolar septal thresholds were 44.4% (P =0.02) and 22.5% (P = 0.12) lower than the means of the unipolar and bipolar apical thresholds (Table2). In this case, although the means are quite similar, the chronic unipolar septal threshold was statistically lower (two-tailed paired t test). In relation to the pacing threshold, these results suggest that the septal pacing can be used or even preferred with no additional risk. R Wave Septal and apical R waves of 21 patients with bifocal implantation in RV were compared. Four patients were completely dependent on the artificial pacing, which made it impossible to measure R wave. The results are shown in Table 2. It was observed that the unipolar and bipolar septal R waves are on average 1.1% and 0.8% higher and lower than the unipolar and bipolar apical R waves, respectively. However, these differences were not statistically significant,


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P = 0.80 and 0.93 (two-tailed paired t test). These findings suggest that despite the septal position shows a slightly lower R wave, the means obtained with this cohort demonstrated excellent values: unipolar and bipolar 10.0 and 12.3 mV, respectively. In the chronic phase, the means of the unipolar and bipolar septal R waves were 20% and 7.1% higher than the means of the unipolar and bipolar apical R waves, respectively, not showing statistically significant difference P = 0.09 and 0.50 (two-tailed paired t test) (Table 2). Accordingly, the amplitude of the R wave does not impose a limitation on septal implantation.

It was observed that the electrical axis of the septal paced QRS was positive and closer to the normal axis. The same situation was observed in relation to the QRS axis of bifocal pacing. Conversely, the mean axis of the QRS resulting from the apical pacing showed great difference in relation to the normal QRS axis. These differences were statistically significant, P = 0.0004 (two-tailed paired t test, measured between septal and apical positions); P1 = 0.0013 (two-tailed paired t test, measured between bifocal and apical positions); P2= 0.001(two-tailed paired t test, measured between bifocal and septal positions). These findings suggest that the electrical axis is more physiological when the QRS results from the septal in relation to the apical pacing. Hence, considering the electrical axis of the paced QRS, the septal pacing should be preferred in relation to the classical pacing, since the physiological progression of the myocardial activation reduces the histological remodeling of the wall of the LV [20], besides improving its hemodynamic performance [24].

Impedances Impedances were compared among 25 patients and it was observed that unipolar and bipolar septal impedances were on average 13.2% and 2.8% lower than the unipolar and bipolar apical impedances, respectively. However, these differences were not statistically significant, P = 0.09 and 0.34 (two-tailed paired t test). In the chronic phase, the means of the unipolar and bipolar septal impedances were respectively 0.6% and 5.1% lower and higher than the mean of unipolar and bipolar apical impedances, not showing statistically significant difference P = 0.8 and 0.24 (twotailed paired t test) (Table 2). These results demonstrate that in relation to the impedance, the septal pacing and the apical pacing are indifferent. QRS Duration (QRSd) Notwithstanding being a secondary endpoint of this study, an extremely relevant finding is that the QRS obtained with septal pacing was significantly narrower than the QRS resulted from the apical pacing (P < 0.01) (Table 3). Several studies demonstrate that in patients with cardiomyopathy, the longer the QRSd, the higher the mortality [21]. Furthermore, a number of evidences indicate that the myocardial desynchronization is proportional to the QRSd. In addition, recent observations corroborate less desynchrony of the LV with septal pacing [22]. Since these facts are now confirmed, we have definitely changed the ventricular pacing from conventional to septal pacing, starting from the 1990s when the advances in technology enabled the use of more suitable active-fixation leads [23]. In all the cases, the RV bifocal paced QRS was the narrowest, so that all the patients of the study could remain with this type of stimulation.

QRS AXIS As secondary endpoint, electrical axis of paced QRS from septum and apex of the 25 bifocal implantations in the RV were also compared. The outcomes are shown in Table 4.

CONCLUSION The data yielded for this study demonstrate that the septal thresholds were slightly lower than the apical ones in an intrapatient comparison. This difference was not statistically significant. The electrical axis obtained in septal position was closer to the normal axis in relation to the apical position with important statistical significance. The measurements of R waves and impedances in septal and apical positions did not show statistically significant differences. The QRS of the septal pacing was significantly narrower than the one produced by apical pacing. These data show that the septal pacing may be regularly used with no electrophysiological objection. Thus, according to the electrophysiological parameters studied here, besides there having no restrictions, there are even advantages in septal pacing, and it must be considered whenever as possible in cases with sole RV lead implantation.

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4. Pignalberi C, Ricci RP, Santini M. Deleterious effects of apical right ventricular stimulation. Should we change our standard method of pacemaker implantation? Ital Heart J Suppl. 2005;6(10):635-48. 5. Hochleitner M, Hörtnagl H, Ng CK, Hörtnagl H, Gschnitzer F, Zechmann W. Usefulness of physiologic dual-chamber pacing in drug-resistant idiopathic dilated cardiomyopathy. Am J Cardiol. 1990;66(2):198-202. 6. Lamas GA, Orav EJ, Stambler BS, Ellenbogen KA, Sgarbossa EB, Huang SK, et al. Quality of life and clinical outcomes in elderly patients treated with ventricular pacing as compared with dual-chamber pacing. Pacemaker Selection in the Elderly Investigators. N Engl J Med. 1998;338(16):1097-104. 7. Pachón MJC, Pachón JC, Pachón MEI, Albornoz RN. Ventricular pacemaker syndrome. Europace. 2001;2(Supl B):B136. 8. Grines CL, Bashore TM, Boudoulas H, Olson S, Shafer P, Wooley CF. Functional abnormalities in isolated left bundle ranch block. The Effect of Interventricular Asynchrony. Am J Cardiol. 2000;86(12):1293-8. 9. Kormann DS, Jatene AD. Triângulo eletrodo vertebrodiafragmático no posicionamento de eletrodo endocavitário para marca-passo cardíaco. Arq Bras Cardiol. 1977;39(Supl. II):380. 10. Bakker PJ, Meijburg H, De Jonge N, Van Mechelen R, Wittkampf FH, Mower M. Beneficial effects of biventricular pacing in congestive heart failure. PACE. 1994;17(II):820. 11. Cazeau S, Leclercq C, Lavergne T, Walker S, Varma C, Linde C, et al; Multisite Stimulation in Cardiomyopathies (MUSTIC) Study Investigators. Effects of multisite biventricular pacing in patients with heart failure and intraventricular conduction delay. N Engl J Med. 2001;344(12):873-80. 12. Pachón JC, Pachón EI, Albornoz RN, Pachón JC, Kormann DS, Gimenes VM, et al. Ventricular endocardial right bifocal stimulation in the treatment of severe dilated cardiomyopathy heart failure with wide QRS. Pacing Clin Electrophysiol. 2001;24(9 Pt 1):1369-76. 13. Pachón Mateos JC, Pachón Mateos EI, Pachón Mateos JC. Right ventricular apical pacing: the unwanted model of cardiac stimulation? Expert Rev Cardiovasc Ther. 2009;7(7):789-99. 14. Gregoratos G, Abrams J, Epstein AE, Freedman RA, Hayes DL, Hlatky MA, et al American College of Cardiology/ American Heart Association Task Force on Practice Guidelines American College of Cardiology/American Heart Association/ North American Society for Pacing and Electrophysiology

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15. Barold SS. Adverse effects of ventricular desynchronization induced by long-term right ventricular pacing. J Am Coll Cardiol. 2003;42(4):624-6. 16. Wilkoff BL, Cook JR, Epstein AE, Greene HL, Hallstrom AP, Hsia H, et al. Dual-chamber pacing or ventricular backup pacing in patients with an implantable defibrillator: the dual chamber and VVI implantable defibrillator (DAVID) trial. Dual chamber and VVI implantable defibrillator trial investigators. JAMA. 2000;288(24):3115-23. 17. Sweeney MO, Hellkamp AS, Ellenbogen KA, Greenspon AJ, Freedman RA, Lee KL, et al. Adverse effect of ventricular pacing on heart failure and atrial fibrillation among patients with normal baseline QRS duration in a clinical trial of pacemaker therapy for sinus node dysfunction. Circulation. 2003;107(23):2932-7. 18. Moss AJ, Zareba W, Hall WJ, Klein H, Wilber DJ, Cannom DS, et al. Prophylactic implantation of a defibrillator in patients with myocardial infarction and reduced ejection fraction. N Engl J Med. 2002;346(12):877-83. 19. Deshmukh PM, Romanyshyn M. Direct his-bundle pacing: present and future. Pacing Clin Electrophysiol. 2004;27(6 pt 2):862-70. 20. Karpawich PP, Justice CD, Chang CH, Gause CY, Kuhns LR. Septal ventricular pacing in the immature canine heart: a new perspective. Am Heart J. 1991;121(3 Pt 1):827-33. 21. Aro AL, Anttonen O, Tikkanen JT, Junttila MJ, Kerola T, Rissanen HA, et al. Intraventricular conduction delay in a standard 12-lead electrocardiogram as a predictor of mortality in the general population. Circ Arrhythm Electrophysiol. 2011;4(5):704-10. 22. Wang F, Shi H, Sun Y, Wang J, Yan Q, Jin W, et al. Right ventricular outflow pacing induces less regional wall motion abnormalities in the left ventricle compared with apical pacing. Europace. 2012;14(3):351-7. 23. Mateos JCP, Albornoz RN, Mateos EIP, Gimenez VM, Mateos JCP, Santos Filho ER, et al. Estimulação ventricular direita bifocal no tratamento da miocardiopatia dilatada com insuficiência cardíaca. Arq Bras Cardiol. 1999;73(6):485-91. 24. Karpawich PP, Mital S. Comparative left ventricular function following atrial, septal, and apical single chamber heart pacing in the young. Pacing Clin Electrophysiol. 1997;20(8 Pt 1):1983-8.


ORIGINAL ARTICLE

Rev Bras Cir Cardiovasc 2012;27(2):203-10

Preoperative risk factors for mediastinitis after cardiac surgery: assessment of 2768 patients Fatores de risco pré-operatórios para mediastinite após cirurgia cardíaca: análise de 2768 pacientes

Marcos Gradim Tiveron1, Alfredo Inácio Fiorelli2, Eduardo Moeller Mota3, Omar Asdrúbal Vilca Mejia4, Carlos Manuel de Almeida Brandão5, Luís A. O. Dallan6, Pablo A. M. Pomerantzeff7, Noedir A.G Stolf8

DOI: 10.5935/1678-9741.20120035

RBCCV 44205-1372

Abstract Background: Longitudinal median sternotomy is the most common surgical approach for access to heart disease treatment. The deep wound infections in postoperative period of cardiovascular surgery are a serious complication requiring high costs during treatment. Different studies have indicated some risk factors for the development of mediastinitis and preoperative variables are currently under investigation. Objective: The aim of this study is to identify the preoperative risk factors for postoperative development of mediastinitis in patients undergoing coronary artery bypass grafting and valve replacement. Methods: This observational study represents a cohort of 2768 consecutive operated patients. The period considered for analysis was from May 2007 to May 2009 and there were no exclusion criteria. Analysis was performed by univariate and multivariate logistic regression model of 38 preoperative variables.

Results: Thirty-five (1.3%) patients developed mediastinitis and 19 (0.7%) associated with osteomyelitis. The patient age average was 59.9 ± 13.5 years and the EuroSCORE of 4.5 ± 3.6. Hospital mortality was 42.8%. The multivariate analysis identified three variables as independent predictors of postoperative mediastinitis: intraaortic balloon pump (OR 5.41, 95% CI [1.83 -16.01], P = 0.002), hemodialysis (OR 4.87, 95% CI [1.41 to 16.86], P = 0.012) and extracardiac vascular intervention (OR 4.39, 95% CI [1.64 to 11.76], P = 0.003). Conclusion: This study showed that necessity of preoperative hemodynamic support with intra-aortic balloon, hemodialysis, and extracardiac vascular intervention were risk factors for development of mediastinitis after cardiac surgery.

1. Cardiovascular surgeon of the Heart Institute at Clinics Hospital of the Faculty of Medicine of the São Paulo University (InCor/ HC-FMUSP), São Paulo, SP, Brazil. Cardiovascular Surgeon of the Santa Casa de Marília, Marília, SP, Brazil. 2. Full Professor at Faculty of Medicine of the University of São Paulo (FMUSP); Director of the Perfusion and Cardio-respiratory Assistance Unit of InCor/HC-FMUSP, São Paulo, SP, Brazil. 3. Resident Physician of Cardiovascular Surgery at InCor/HCFMUSP, São Paulo, SP, Brazil. 4. Cardiovascular Surgeon, PhD student in Sciences of the Postgraduation Program in Thoracic and Cardiovascular Surgery at FMUSP, São Paulo, SP, Brazil. 5. PhD in Medicine at FMUSP. Assistant Physician of the Valve Heart Diseases Unit at InCor/HC-FMUSP, São Paulo, SP, Brazil. 6. Full Professor, Director of the Coronary Heart Diseases Surgical Unit at InCor/HC-FMUSP, São Paulo, SP, Brazil. 7. Full Professor, Director of the Valve Heart Diseases Surgical Unit

at InCor/HC-FMUSP, São Paulo, SP, Brazil. 8. Titular Professor of the Discipline of Cardiovascular Surgery at FMUSP; Director of the Cardiovascular Surgery Division at InCor/ HC-FMUSP, São Paulo, SP, Brasil.

Descriptors: Mediastinitis. Postoperative complications. Surgical wound infection. Preoperative care.

This study was carried out at Clinics Hospital of the Faculty of Medicine of the University of São Paulo (InCor-HC/FMUSP), São Paulo, Brazil. Correspondence address: Marcos Gradim Tiveron. Av. Dr. Enéas de Carvalho Aguiar, 44 – Cerqueira César – São Paulo, SP, Brazil – Zip Code: 05403-900. E-mail: mgtiveron@yahoo.com.br

Article received on September 21st, 2011 Article accepted on January 26th, 2012

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Tiveron MG, et al. - Preoperative risk factors for mediastinitis after cardiac surgery: assessment of 2768 patients

Abbreviations, Acronyms & Symbols IAB IAC DM COPD VAD LVEF VF PH AMI CHF BMI OI PM SD NYHA CABG VT AoV LV MiV

Intra-aortic balloon Interventricular communication Diabetes mellitus Chronic obstructive pulmonary disease Vasoactive drugs Left ventricular ejection fraction Ventricular fibrillation Pulmonary hypertension Acute myocardial infarction Congestive Heart Failure Body Mass Index Orotracheal intubation Pacemaker Sudden death New York Heart Association Cardiopulmonary bypass grafting Ventricular tachycardia Aortic valve Left ventricle Mitral valve

Resumo Introdução: A esternotomia mediana longitudinal é a via de acesso mais utilizada no tratamento das doenças cardíacas. As infecções profundas da ferida operatória no pós-operatório das cirurgias cardiovasculares são uma complicação séria, com alto custo durante o tratamento. Diferentes estudos têm encontrado

INTRODUCTION Median sternotomy is a surgical approach most commonly used in the repair of heart disease. The deep surgical wound infections in cardiovascular surgeries are a serious complication due to morbidity and high costs that are required for the treatment. Its incidence varies between 0.4% and 5%, and even with existing early diagnosis and different treatment modalities, it is still a serious complication. It has high morbidity and mortality, with numbers ranging between 14% and 47% [1]. According to Horan et al. [2], mediastinitis is defined as an infection that affects sternotomy superficially and deeper tissues, occurring within the first thirty days postoperatively and with the presence of the following criteria: (a) pain or sternal instability associated with at least one of the findings: purulent drainage through the retrosternal area, blood positive culture or drained secretion and increased in the mediastinal imaging test (b) positive culture of secretion from the mediastinum, (c) evidence of retrosternal infection during operation or histological 204

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fatores de risco para o desenvolvimento de mediastinite e as variáveis pré-operatórias têm tido especial destaque. Objetivo: O objetivo deste estudo é identificar fatores de risco pré-operatórios para o desenvolvimento de mediastinite em pacientes submetidos a revascularização do miocárdio e a substituição valvar. Métodos: Este estudo observacional representa uma coorte de 2768 pacientes operados consecutivamente. O período considerado para análise foi de maio de 2007 a maio de 2009 e não houve critérios de exclusão. Foi realizada análise univariada e multivariada pelo modelo de regressão logística das 38 variáveis pré-operatórias eleitas. Resultados: Nesta série, 35 (1,3%) pacientes evoluíram com mediastinite e 19 (0,7%) com osteomielite associada. A idade média dos pacientes foi de 59,9 ± 13,5 anos e o EuroSCORE de 4,5 ± 3,6. A mortalidade hospitalar foi de 42,8%. Na análise multivariada, foram identificadas três variáveis como preditoras independentes de mediastinite: balão intra-aórtico (OR 5,41, 95% IC [1,83 -16,01], P=0,002), hemodiálise (OR 4,87, 95% IC [1,41 - 16,86], P=0,012) e intervenção vascular extracardíaca (OR 4,39, 95% IC [1,64 - 11,76], P=0,003). Conclusão: O presente estudo demonstrou que necessidade do suporte hemodinâmico pré-operatório com balão intra-aórtico, hemodiálise e intervenção vascular extracardíaca são fatores de risco para o desenvolvimento de mediastinite após cirurgia cardíaca. Descritores: Mediastinite. Complicações pós-operatórias. Infecção da ferida operatória. Cuidados pré-operatórios.

analysis. Most deep infections occurring between one and two weeks after surgery [3]. If there is suspicion of osteomyelitis, confirmation should be performed by pathological examination of a fragment of the sternum removed during the surgical procedure of cleaning. The most frequent clinical findings are the signs of inflammation such as redness, warmth, swelling and pain in the wound. The dehiscence and drainage of wound secretion occurring in about 70% to 80% of cases, and may or may not be related to instability of the sternum. The patient may present with fever and clinical signs of sepsis or shock, multiple organ failure, if the diagnosis is delayed. Mediastinitis can manifest itself until the first six weeks postoperatively. After this period, its occurrence is rare, but when present, the resolution is more complex [1]. Complementary research is performed by thoracic (mediastinal widening, unilateral or bilateral pleural effusion and sternal dehiscence), complete blood count and blood cultures (leukocytosis with a shift to the left of young cells and identification of the causative agent), computed tomography (collection present in the mediastinum and may


Tiveron MG, et al. - Preoperative risk factors for mediastinitis after cardiac surgery: assessment of 2768 patients

be with or without peristernal abnormalities such as edema or blurring of soft parts, separation of the sternum and marginal bone resorption, bone sclerosis or indirect signs of osteomyelitis) and bone scintigraphy (identifies signs of inflammatory activity and process infection in the sternum). Different studies have chosen some risk factors for the development of mediastinitis [4-7], which are listed in Chart 1. Therapeutic options for the treatment of mediastinitis include debridement with early or late closure of the chest, debridement and closure with continuous irrigation using 0.9% saline solution, partial or total sternectomy associated to reconstruction of muscle flaps or caul, in addition to adjuvant therapies, such as the system of vacuum-assisted therapy and hyperbaric oxygenation [8-12]. The aim of this study is to identify risk factors for preoperative development of mediastinitis in patients undergoing coronary artery bypass grafting and valve replacement. Chart 1. Risk factors associated with mediastinitis. Preoperative risk factors Diabetes mellitus Peripheral vascular disease Obesity (BMI> 30) Congestive heart failure (NYHA III and IV) Age> 75 years Immunosuppression state Chronic lung disease Male Intra-and postoperative risk factors Need for mechanical circulatory support Reoperation for bleeding Use of both internal thoracic arteries Cardiopulmonary bypass time> 300 minutes Blood loss in Postoperative Recovery Unit Sternal fracture and osteoporosis Polytransfusion blood

NYHA - New York Heart Association; IAB - Intra-aortic Balloon, BMI - Body Mass Index

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METHODS This study represents an observational cohort. The data of 2768 consecutive patients were collected retrospectively and operations in this group are distributed as follows: 1216 (44%) valvular treatment and 1552 (56%) CABG. The period considered for the analysis was from May 2007 to May 2009 and there were no exclusion criteria. We performed univariate and multivariate logistic regression model for the 38 preoperative variables studied and listed in Chart 2. Statistical Analysis For statistical analysis, we used quantitative variables (EuroSCORE, age) the Student’s t test for comparison of independent groups according to the presence or absence of osteomyelitis and mediastinitis. For qualitative variables (gender, congestive heart failure, chronic obstructive pulmonary disease, diabetes mellitus, left ventricular ejection fraction, obesity, reoperation, intraaortic balloon, aortic and mitral valve replacement, coronary artery bypass grafting associated to valve replacement, cardiogenic shock, treated endocarditis, post-infarction ventricular septal defect, resectable left ventricular aneurysm, tricuspid valve replacement, ventricular tachycardia, ventricular fibrillation and sudden death, pacemaker dependency, acute myocardial infarction within 48h of evolution, asthma, preoperative intubation, pulmonary hypertension (> 25 mmHg), cirrhosis, dependence on hemodialysis, carotid artery disease, blood reactions, neurological disorders, preoperative vasoactive drug, unstable angina, emergency surgery, thoracic aortic operations, preoperative cardiac massage, MI infarction <90 days, creatinine (> 2.26 mg/dl), abuse of illicit drugs, intervention in the abdominal aorta, carotid artery or branch), we used the chi-square, and when it was not possible, by theoretical constraint, the Fisher exact test to compare groups according to the presence or absence of osteomyelitis and mediastinitis (Table 1).

Chart 2. Preoperative variables chosen for analysis Gender Age LVEF Aortic valve replacement Preoperative IAB Mitral valve replacement Cardiogenic shock Treated endocarditis Post-infarction IVC VT/VF/SD PM-dependent AMI within 48h of evolution DM PH (>30 mmHg) Cirrhosis Drug-dependent Carotid disease Blood Reaction AMI < 90 days Preoperative VAD unstable angina Preoperative cardiac massage Creatinine (>2,26mg/dl)

Obesity (BMI > 30) Reoperation CABG + Valve DPOC Resectable LV aneurysm Tricuspid valve replacement Asthma Preoperative OI Hemodialysis-dependent CHF EuroSCORE Neurological disorders Emergency Surgery Thoracic aortic surgery intervention in the abdominal aorta, carotid artery or branch

IAB: intra-aortic balloon; IVC: interventricular communication; VAD: vasoactive drugs; COPD: Chronic obstructive pulmonary disease, DM: Diabetes mellitus, LVEF: Left ventricular ejection fraction of the left ventricle; VF: ventricular fibrillation; HP: Pulmonary hypertension; CHF: Congestive heart failure, BMI: Body mass index, AMI: Acute myocardial infarction; TI: Tracheal intubation: SD: Sudden death; PM: Pacemaker, CABG: Coronary artery bypass grafting; VT: Ventricular tachycardia, LV: left ventricle

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By univariate analysis, the variables intra-aortic balloon, hemodialysis and intervention in the abdominal aorta, carotid or arterial branch are variables associated with mediastinitis. The variables diabetes, ejection fraction of the left ventricle and creatinine showed P values between 5% and 10%. Thus, these variables were selected for

multivariate logistic model. To obtain the final model, we used the stepwise selection process, whereby the following variables selected were: intra-aortic balloon, hemodialysis and extracardiac vascular intervention. Table 2 presents the odds ratios and 95% CI for each variable and for the final model.

Table 1. Analyzed variables and their “P” values. Variables analyzed Mean EuroSCORE Mean age Male Female CHF COPD DM Mean LVEF Obesity (BMI > 30) Reoperation Preoperative IAB AoV replacement MiV replacement CABG + Valve Cardiogenic shock Treated endocarditis Post-infarction IVC LV resectable aneurysm Tricuspid valve replacement VT/VF/SD PM-dependent AMI within 48h of evolution Asthma Preoperative OI PH (> 25 mmHg) Cirrhosis Hemodialysis-dependent Carotid disease Blood reaction Neurological disorders Preoperative VAD Unstable angina Emergency surgery Surgery of the thoracic aorta Preoperative cardiac massage AMI < 90 days Creatinine ( > 2,26mg/dl) Abuse of illicit drugs Intervention in the abdominal aorta, carotid or other artery branch

With Mediastinitis n =35 4.9 ±3.8 60.6 ±13.8 74.2% 25.8% 22 (62.8%) 2 (5.7%) 16 (45.7%) 51.6 ±13.4 6 (17.1%) 3 (8.5%) 4 (11.4%) 5 (14.2%) 9 (25.7%) 1 (2.8%) 0 1 (2.8%) 0 1 (2.8%) 3 (8.5%) 2 (5.7%) 0 2 (5.7%) 0 1 (2.8%) 8 (22.8%) 0 3 (8.5%) 4 (11.4%) 0 3 (8.5%) 3 (8.5%) 4 (11.4%) 0 1 (2.8%) 0 9 (25.7%) 4 (11.4%) 3 (8.5%)

Without Mediastinitis n =2733 4.5 ±3.6 59.9 ±13.4 64.7% 35.3% 1808 (66.2%) 72 (2.6%) 857 (31.3%) 55.4 ±13.6 248 (9%) 477 (17.4%) 71 (2.6%) 603 (22%) 714 (26.1%) 183 (6.7%) 32 (1,1%) 111 (4%) 16 (0.6%) 88 (3.2%) 146 (5.3%) 59 (2.1%) 59 (2.1%) 57 (2%) 11 (0.4%) 46 (1.6%) 655 (23.9%) 12 (0.4%) 46 (1.6%) 242 (8.8%) 28 (1%) 193 (7%) 146 (5.3%) 192 (7%) 88 (3.2%) 20 (0.7%) 4 (0.1%) 453 (16.5%) 132 (4.8%) 342 (12.5%)

5 (14.2%)

106 (3.8%)

P values 0.508 0.768 0.238 0.682 0.240 0.069 0.105 0.129 0.594 0.014 0.269 0.956 0.727 1,000 1.000 1.000 1,000 0.433 0.179 1,000 0.170 1.000 0.453 0.879 1.000 0.023 0.547 1.000 0.734 0.433 0.308 0.627 0.235 1.000 0.150 0.090 0.614 0.012

IAB: intra-aortic balloon; IVC: interventricular communication; VAD: vasoactive drugs; COPD: Chronic obstructive pulmonary disease, DM: Diabetes mellitus, LVEF: Left ventricular ejection fraction of the left ventricle; VF: ventricular fibrillation; HP: Pulmonary hypertension; CHF: Congestive heart failure, BMI: Body mass index, AMI: Acute myocardial infarction; TI: Tracheal intubation: SD: Sudden death; PM: Pacemaker, CABG: Coronary artery bypass grafting; VT: Ventricular tachycardia, LV: left ventricle

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Table 2. Univariate and multivariate models for analysis of selected variables. Variable DM EF IAB Hemodialysis Creatinine > 2.26mg/dl Extracardiac Vascular Intervention

Univariate Model 95% CI Odds ratio LL UL

P

Multivariate Model 95% CI Adjusted LL UL Odds ratio

P

1.84 0.98 4.83 5.48 2.54

0.94 0.96 1.66 1.62 0.89

3.60 1.00 14.07 18.53 7.31

0.074 0.108 0.004 0.006 0.083

5.41 4.87

1.83 1.41

16.01 16.86

0.002 0.012

4.13

1.57

10.86

0.004

4.39

1.64

11.76

0.003

IAB: Intra-aortic Balloon DM: Diabetes Mellitus EF: Ejection Fraction CI - Confidence Interval LL – UL: Lower Limit - Upper Limit

RESULTS Of the 2768 patients who underwent surgery, 35 (1.3%) patients developed mediastinitis and 19 (0.7%) with osteomyelitis. Most patients were male (72.4%). Of the 35 patients with mediastinitis, 24 (68.5%) had undergone CABG and 11 (31.5%), valve replacement. Among the 18 patients with osteomyelitis, 13 (72.2%) underwent CABG and five (27.7%), valve replacement. The mean age of patients was 59.9 ± 13.5 years and EuroSCORE of 4.5 ± 3.6. Hospital mortality was 42.8%. The univariate analysis identified the following risk factors: diabetes mellitus (OR 1.84-95% CI [0.94 to 3.6], P = 0.074), left ventricular ejection fraction (OR 0.98 - 95% CI [0.96 to 1.00], P = 0.108), intraaortic balloon (OR 4.83-95% CI [1.66 to 14.07], P = 0.004), dialysis (OR, 5.48-95% CI [1.62 to 18.53], P = 0.006), creatinine> 2.26 mg / dl (OR 2.54-95% CI [0.89 to 7.31], P = 0.083) and extracardiac vascular intervention (OR 4.13 - 95% CI [1.57 to 10.86], P = 0.04). After multivariate analysis, we selected: intra-aortic balloon (OR 5.41-95% CI [1.83 16.01], P = 0.002), dialysis (OR 4.87-95% CI [1.41 - 16.86], P = 0.012) and extracardiac vascular intervention (OR 4.39-95% CI [1.64 to 11.76], P = 0.003). DISCUSSION Access to the structures of the anterior mediastinum by longitudinal median sternotomy and its synthesis with wires were first described by Milton in 1897, and gained widespread since the advent of cardiopulmonary bypass, and currently is one of the most commonly used surgical incisions in the world [13 , 14]. While providing an excellent approach to the heart and great vessels, it is difficult to immobilize this opening safely, due to the constant movement and effort to breathe and cough. The pathophysiology of mediastinitis is complex and multifactorial. The excessive handling of inpatient, as

prolonged use of central venous catheters and hemodialysis, venous and arterial punctures for collection of repeated examinations in immunocompromised patients or in a poor state of nutrition, favors the entry and action of pathogens. Cardiac transplantation is presented as additional risk factor for the development of mediastinitis, by the presence of immunosuppression [15,16]. Furthermore, the involvement of sternal irrigation after dissection of left internal thoracic artery, right or both, in patients with low tissue perfusion consequent to a state of low cardiac output, also facilitate the action of bacteria [17]. Recent studies indicate that the male patient is more prone to develop mediastinitis and is an independent risk factor for its development [18-20]. In the present study, as well as that published by Sá et al. [21], there was a higher incidence of mediastinitis in male patients. One of the probable mechanisms relates to the anatomy of man. Recent studies have shown that females exhibit greater collateral circulation, which gives greater protection to women, and hair follicles in the sternotomy region present in greater numbers in men favor the growth and bacterial infection [22,23]. Furthermore, the male presents higher rates of diabetes mellitus [24,25]. The presence of diabetes impairs wound healing and cellular and humoral immunity, which leads to increased risk of infections, especially in patients who take insulin to control blood glucose [26]. In the present study, were identified as risk factors in the univariate analysis, diabetes mellitus, ejection fraction, intra-aortic balloon, hemodialysis, creatinine greater than 2.26 mg/dl and extracardiac vascular intervention. After multivariate analysis, there was a statistically significant incidence of sternal complications in patients using preoperative intra-aortic balloon, hemodialysis and those who underwent extracardiac vascular interventions. It is believed that the first two risk factors are associated with invasive manipulation in the preoperative period through vascular punctures and the prolonged period between 207


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admission and surgery, beyond the state of tissue hypoperfusion caused by cardiogenic shock which led to insertion the intra-aortic balloon [27]. Regarding the third risk factor, the presence of peripheral artery disease associated with extracardiac vascular disease requiring surgical intervention relates to the state of tissue hypoperfusion that affected also the sternum. Rahmanian et al. [28] demonstrated a higher hospital mortality in patients with chronic renal deep sternal infection who were dependent on dialysis. Other studies confirm the relationship between increased mortality and renal failure alone or associated with other complications, which may vary between 30% and 80% [29,30]. Different studies were designed to establish risk scores for mediastinitis and, thus, act preemptively, decreasing morbidity and mortality, in addition to hospital costs resulting from prolonged hospitalization [31-34]. Magedanz et al. [35] assessing 2809 patients, identified five risk factors for mediastinitis in patients undergoing coronary artery bypass grafting, which include chronic obstructive pulmonary disease, obesity, multiple blood transfusions in the postoperative, surgical intervention and angina class IV. The need for surgical intervention was a risk factor for mediastinitis most important in this group of patients. From these data, the authors formulated a risk score for postoperative mediastinitis in myocardial revascularization, which was later validated by Sá et al. [20]. Another recently published study examined 107 patients who developed mediastinitis in a cohort of 18,532 patients who underwent CABG and with a mean follow up of 10.3 years [36]. The authors identified as independent risk factors for developing mediastinitis: COPD, age, male gender, stenosis of the left main coronary artery, diabetes mellitus and obesity (BMI> 30 kg/m2). These last two were also identified as risk factors for mediastinitis after coronary artery bypass surgery by Sá et al. [37], and they reinforced also in other publications [38.39], the importance of obtaining the internal thoracic artery grafting with skeletonized dissection technique in high-risk groups, in order to reduce the incidence of this complication. Limitations of the Study The study was limited to the analysis of preoperative risk factors, not including intraoperative or postoperative variables, without identifying other risk factors for developing mediastinitis. Despite being performed in a hospital of national reference, it only involves a single center, where routine of preoperative care is the same for all patients. It is an observational study and presents some limitations of the drawing itself, and therefore, further studies with larger samples are needed. 208

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CONCLUSION The need for the use of preoperative intra-aortic balloon, hemodialysis and extracardiac vascular surgery present as statistically significant risk factors for the occurrence of postoperative mediastinitis in CABG and valvular treatment. Based on the analysis of the results obtained in the present study, we observed that patients using preoperative intra-aortic balloon present chance of occurrence of mediastinitis 5.4 times higher than patients without intra-aortic balloon. Patients undergoing hemodialysis and preoperative extracardiac vascular intervention also present increased odds of mediastinitis with rates of approximately 4.9 times and 4.4 times greater than the other, respectively. ACKNOWLEDGMENTS Data analysis of this study was performed with consulting of the Extension Project: “Statistical consulting to students and teachers of undergraduate and postgraduate programs of FFC-CM, UNESP and other researchers linked to other educational institutions. Coordinator: Prof. Sebastião Marcos Ribeiro de Carvalho, Assistant Full Professor of the Department of Educational Psychology, FFC, UNESP, Marília)”.

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17. Milani R, Brofman PR, Guimarães M, Barboza L, Tchaick RM, Meister Filho H, et al. Double skeletonized internal thoracic artery vs. double conventional internal thoracic artery in diabetic patients submitted to OPCAB. Rev Bras Cir Cardiovasc. 2008;23(3):351-7. 18. Borger MA, Rao V, Weisel RD, Ivanov J, Cohen G, Scully HE, et al. Deep sternal wound infection: risk factors and outcomes. Ann Thorac Surg. 1998;65(4):1050-6. 19. Demmy TL, Park SB, Liebler GA, Burkholder JA, Maher TD, Benckart DH, et al. Recent experience with major sternal wound complications. Ann Thorac Surg. 1990;49(3):458-62. 20. Sá MPBO, Figueira ES, Santos CA, Figueiredo OJ, Lima ROA, Rueda FG, et al. Validação do MagedanzSCORE como preditor de mediastinite após cirurgia de revascularização do miocárdica. Rev Bras Cir Cardiovasc. 2011;26(3):386-92.

8. Cabbabe EB, Cabbabe SW. Surgical management of the symptomatic unstable sternum with pectoralis major muscle flaps. Plast Reconstr Surg. 2009;123(5):1495-8.

21. Sá MPBO, Silva DO, Lima ENS, Lima RC, Silva FPV, Rueda FG, et al. Mediastinite no pós-operatório de cirurgia cardiovascular. Análise de 1038 cirurgias consecutivas. Rev Bras Cir Cardiovasc. 2010;25(1):19-24.

9. Sun IF, Lee SS, Chiu CC, Lin SD, Lai CS. Hyperbaric oxygen therapy with topical negative pressure: an alternative treatment for the refractory sternal wound infection. J Card Surg. 2008;23(6):677-80.

22. Grossi EA, Esposito R, Harris LJ, Crooke GA, Galloway AC, Colvin SB, et al. Sternal wound infections and use of internal mammary artery grafts. J Thorac Cardiovasc Surg. 1991;102(3):342-6.

10. Brito JD, Assumpção CR, Murad H, Jazbik AP, Sá MPL, Bastos ES, et al. Manuseio em um estágio de esternotomia infectada com avanço bilateral de flap miocutâneo do peitoral maior. Rev Bras Cir Cardiovasc. 2009;24(1): 58-63.

23. Seyfer AE, Shriver CD, Miller TR, Graeber GM. Sternal blood flow after median sternotomy and mobilization of the internal mammary arteries. Surgery. 1988;104(5):899-904.

11. van Wingerden JJ, Coret ME, van Nieuwenhoven CA, Totté ER. The laparoscopically harvested omental flap for deep sternal wound infection. Eur J Cardiothorac Surg. 2010;37(1):87-92. 12. Nina VJ, Assef MA, Rodrigues RR, Mendes VG, Lages JS, Amorim AM, et al. Reconstruction of the chest wall with external metal brace: alternative technique in poststernotomy mediastinitis. Rev Bras Cir Cardiovasc. 2008;23(4):507-11. 13. Milton H. Mediastinal surgery. Lancet. 1897;1:872-5. 14. Julian OC, Lopez-Belio M, Dye WS, Javid H, Grove WJ. The median sternal incision in intracardiac surgery with extracorporeal circulation: a general evaluation of its use in heart surgery. Surgery. 1957;42(4):753-61. 15. Stolf NA, Fiorelli AI, Bacal F, Camargo LF, Bocchi EA, Freitas A, et al. Mediastinitis after cardiac transplantation. Arq Bras Cardiol. 2000;74(5):419-30. 16. Uip DE, Amato Neto V, Strabelli TMV, Bocchi EA, Fiorelli A,

24. Ottino G, De Paulis R, Pansini S, Rocca G, Tallone MV, Comoglio C, et al. Major sternal wound infection after openheart surgery: a multivariate analysis of risk factors in 2,579 consecutive operative procedures. Ann Thorac Surg. 1987;44(2):173-9. 25. Risk factors for deep sternal wound infection after sternotomy: a prospective, multicenter study. J Thorac Cardiovasc Surg. 1996;111(6):1200-7. 26. Rayfield EJ, Ault MJ, Keusch GT, Brothers MJ, Nechemias C, Smith H. Infection and diabetes: the case for glucose control. Am J Med. 1982;72(3):439-50. 27. Le Guillou V, Tavolacci MP, Baste JM, Hubscher C, Bedoit E, Bessou JP, et al. Surgical site infection after central venous catheter-related infection in cardiac surgery. Analysis of a cohort of 7557 patients. J Hosp Infect. 2011;79(3):236-41. 28. Rahmanian PB, Adams DH, Castillo JG, Carpentier A, Filsoufi F. Predicting hospital mortality and analysis of long-term survival after major noncardiac complications in cardiac surgery patients. Ann Thorac Surg. 2010;90(4):1221-9.

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29. Bove T, Calabrò MG, Landoni G, Aletti G, Marino G, Crescenzi G, et al. The incidence and risk of acute renal failure after cardiac surgery. J Cardiothorac Vasc Anesth. 2004;18(4):442-5.

34. Friedman ND, Bull AL, Russo PL, Leder K, Reid C, Billah B, et al. An alternative scoring system to predict risk for surgical site infection complicating coronary artery bypass graft surgery. Infect Control Hosp Epidemiol. 2007;28(10):1162-8.

30. Chertow GM, Levy EM, Hammermeister KE, Grover F, Daley J. Independent association between acute renal failure and mortality following cardiac surgery. Am J Med. 1998;104(4):343-8. 31. Kohli M, Yuan L, Escobar M, David T, Gillis G, Comm B, et al. A risk index for sternal surgical wound infection after cardiovascular surgery. Infect Control Hosp Epidemiol. 2003;24(1):17-25.

35. Magedanz EH, Bodanese LC, Guaragna JCVC, Albuquerque LC, Martins V, Minossi SD, et al. Elaboração de escore de risco para mediastinite pós-cirurgia de revascularização do miocárdio. Rev Bras Cir Cardiovasc. 2010;25(2):154-9. 36. Risnes I, Abdelnoor M, Almdahl SM, Svennevig JL. Mediastinitis after coronary artery bypass grafting risk factors and long-term survival. Ann Thorac Surg. 2010;89(5):1502-9.

32. Eagle KA, Guyton RA, Davidoff R, Edwards FH, Ewy GA, Gardner TJ, et al; American College of Cardiology; American Heart Association. ACC/AHA 2004 guideline update for coronary artery bypass graft surgery: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee to Update the 1999 Guidelines for Coronary Artery Bypass Graft Surgery). Circulation. 2004;110(14):e340-437.

37. Sá MP, Soares EF, Santos CA, Figueiredo OJ, Lima RO, Escobar RR, et al. Risk factors for mediastinitis after coronary artery bypass grafting surgery. Rev Bras Cir Cardiovasc. 2011;26(1):27-35.

33. Braxton JH, Marrin CA, McGrath PD, Ross CS, Morton JR, Norotsky M, et al. Mediastinitis and long-term survival after coronary artery bypass graft surgery. Ann Thorac Surg. 2000;70(6):2004-7.

39. Sá MPO, Santos CA, Figueiredo OJ, Lima RO, Ferraz PE, Soares AM, et al. Skeletonized internal thoracic artery is associated with lower rates of mediastinitis in elderly undergoing coronary artery bypass grafting. Rev Bras Cir Cardiovasc. 2011;26(4):617-23.

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ORIGINAL ARTICLE

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Impact of socio-economic profile on the prosthesis type choice used on heart surgery Impacto do perfil socioeconômico na escolha da prótese valvar em cirurgia cardíaca

André Maurício S. Fernandes1, Larissa Santana Bitencourt2, Igor Nogueira Lessa3, Agnaldo Viana4, Felipe Pereira2, Gabriel Bastos2, Cristiano Ricardo Bastos de Macedo5, Roque Aras Júnior6

DOI: 10.5935/1678-9741.20120056

RBCCV 44205-1373

Abstract Background: Valvar heart disease is an important public health problem, more common in developing countries, especially in younger. Objective: To evaluate the epidemiological features of patients and its influence on the prosthesis type choice used on patients who underwent valve surgery. Methods: Cross-sectional. Data such as age, sex, provenance, surgery procedure and prosthesis type were retrospectively analyzed. We reviewed 366 charts of all patients submitted to heart valve surgery during three years in a public health cardiovascular treatment center. Results: 52% of patients were female. The age range was from 5 to 82, the median was 41 years old. In regards 37.7% of patients came from Salvador (Bahia, Brazil) and 62.3% from countryside. Valve replacement was performed in 73% of patients, whereas 7.38% underwent valvuloplasty and 18.3% underwent valve repair and replacement. Regarding

type of prosthesis, 70.0% received bioprosthesis and 30.0% received metal prosthesis. On note bioprosthesis were more used in younger (66 vs. 14; P<0,001). Conclusion: Biological prostheses were used predominantly in younger. This might be possible due to a low social-economic status, avoiding metal valve implantation and the consequent anticoagulation therapy.

1. Cardiologist Physician; Preceptor of the Admission Unit of the Ana Nery Hospital – Federal University of Bahia (UFBA), Salvador, BA, Brazil. 2. Student of Medicine of Escola Bahiana de Medicina e Saúde Pública, Salvador, BA, Brazil. 3. Cardiologist Physician at UFBA, Salvador, BA, Brazil. 4. Physician at UFBA, Salvador, BA, Brasil. 5. Cardiologist at University Hospital Professor Edgar Santos, Salvador, BA, Brazil. 6. Adjunct Professor at UFBA, Medical Director at Hospital Ana Nery – UFBA, Salvador, BA, Brazil.

This study was carried out at Hospital Ana Nery – Federal University of Bahia, Salvador, BA, Brasil.

Descriptors: Heart valve diseases. Prosthesis implantation. Socioeconomic factors.

Resumo Introdução: A doença cardíaca valvar é um grave problema de saúde pública, mais frequente em países em desenvolvimento, acometendo indivíduos em idade laboralmente produtiva. Objetivo: Avaliar o perfil socioeconômico e

Correspondence address: Larissa Santana Bittencourt Rua Saldanha Marinho, S/N – Caixa D’Água – Salvador, BA, Brazil – Zip code: 40320-010. E-mail: lari.bitencourt@hotmail.com Article received on February 14th, 2011 Article accepted on April 23th, 2012

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Abbreviations, Acronyms & Symbols SD EF NR R SUS

Standard deviation Ejection fraction Non-rheumatic Rheumatic Unified Health System

epidemiológico dos pacientes submetidos a cirurgia valvar e a sua relação com os tipos de próteses utilizadas em um centro de referência público de Salvador, BA, Brasil. Métodos: Estudo de corte transversal descritivo de prevalência, no qual foram analisados retrospectivamente idade, sexo, procedência, tipo de valvopatia, cirurgia a qual o paciente foi submetido e o tipo de prótese utilizada em casos de trocas, em centro de referência público de cardiologia. Resultados: Foram revisados 366 prontuários, de todos os pacientes submetidos a cirurgia de valva cardíaca, de janeiro de 2007 a dezembro de 2009. Em relação ao sexo, 52% dos

INTRODUCTION Most valvular heart disease can cause valvular stenosis with obstruction to anterograde flow, valvular failure with retrograde flow, or both [1]. The valve abnormalities may be caused by congenital disorders or by a variety of acquired diseases, such as, for example, rheumatic fever [2], which occurs at an early age, reproductive and active labor phase of individuals, marking significant differences in the socioepidemiologic aspect when compared to developed countries [3]. Rheumatic disease remains a major public health problem in developing countries [3]. In Brazil, rheumatic disease is a disease with a higher cost to the Unified Health System (SUS). It is estimated that 30% of cardiac surgeries in the country are associated with valvular sequelae of rheumatic fever [1]. Over a period of 18 months between 1995 and 1996, 18,500 cases of rheumatic disease were treated, resulting in 1.8 million doctor visits and 4,500 surgical procedures, with an estimated cost of R$ 19 million [4]. According to latest data from the Ministry of Health, in 2010 there were 12,917 hospitalizations for rheumatic disease, resulting in an approximate cost of R$72 million [5]. In a study performed in Rio Grande do Sul, the heart valve diseases are around 12% to 15% of outpatient and 212

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pacientes eram do sexo feminino. A idade média ± DP foi de 41,70 ± 17,85 anos. Dentre os pacientes, 37,7% eram procedentes da capital e 62,3%, do interior do estado da Bahia (Brasil). A troca valvar foi realizada em 73% dos pacientes, enquanto que 7,38% realizaram plastia valvar e 18,3% realizaram tanto plastia quanto troca. Dos pacientes que realizaram troca valvar, 70% receberam bioprótese e 30% do tipo metálica, com predominância do uso bioprótese nas faixas etárias jovens (P<0,001). Conclusão: Próteses biológicas foram predominantemente usadas em jovens. Esse fato, possivelmente, pode ser atribuído ao baixo nível socioeconômico da população em questão, distância de centros urbanos, dificuldade de realização de exames para controle da anticoagulação e nível educacional ruim, inviabilizando o uso de valva metálica e a consequente terapia anticoagulante. Descritores: Doenças das valvas cardíacas. Implante de prótese. Fatores socioeconômicos.

the incidence of valvular heart disease is approximately 220 patients/year [6]. Still, the Brazilian data of prevalence and epidemiological studies in the population are scarce and controversial, particularly in the city of Salvador, Bahia, Brazil. The aim of this study was to assess the impact of socioepidemiologic profile of patients undergoing valve surgery and its relation to the types of prostheses used in a public reference center of Salvador, Bahia, Brazil. METHODS This is a descriptive cross-sectional study of prevalence, which were retrospectively assessed data as gender, origin, age, length of hospital stay, etiology, main valves involved, echocardiographic data, the type of surgery the patient underwent and type of prosthesis used in cases of replacement, through the review of 366 medical records, transcribed in standard form. For this purpose, samples were defined as all patients undergoing cardiac surgery for valve repair or replacement from January 2007 to December 2009 in a public referral center located in the city of Salvador, Bahia, Brazil. The variables were tested for normality and as mean ± standard deviation (SD) when classified as normal distribution, and median when the distribution was


Fernandes AMS, et al. - Impact of socio-economic profile on the prosthesis type choice used on heart surgery

Rev Bras Cir Cardiovasc 2012;27(2):211-6

abnormal. For categorical variables we used the analysis with chi-square and, for continuous variables, means were compared using Student’s t test. Data were assessed using SPSS version 17.0. The project was approved by the Ethics Committee of Hospital Ana Nery, under protocol 59/10.

mitral valves in 186 patients, followed by the simultaneous involvement of aortic and mitral valves in 176 patients. The remaining patients had other possible combinations, with values much less expressive. Rheumatic disease was the main cause of valve disease, and 211 (57.6%) patients had rheumatic etiology and 128 (35%), non-rheumatic valvular heart disease. In the population studied, we found that the etiologies of valve disease of 27 (7.4%) patients were not defined. Of the 176 male patients, 76 (43.18%) had rheumatic valve disease, while 82 (46.59%) had non-rheumatic lesions, 18 (10.23%) patients had no records on the cause of valve disease. Among female, 135 (71.05%) had rheumatic valve disease and 46 (24.21%) patients had non-rheumatic lesions (P <0.001). Nine (4.74%) women had no clear cause (Table 1).

RESULTS General Characteristics The sample was constituted by 366 patients who underwent cardiac surgery for valve replacement or repair, of which 176 (48%) were male and 190 (52%) were female. The patients’ ages ranged from 5 to 82 years, averaging 41.7 ± 17.8 years. As regards origin, 138 (37.7%) were from the state capital, while 228 (62.3%) were from the countryside. The number of days of hospitalization ranged from 1 to 163, with a median of 24 days. As for valve lesions, 714 valves were affected, of these, 470 valve presented failure, 185, double lesion, and 59 stenosis. The valve lesion and lesion type (stenosis, failure or double lesion) are detailed in Figure 1. Regarding the simultaneous involvement of the valves, the prevailing association occurred with the tricuspid and

Echocardiographic data Ejection fraction (EF) was 62.68 ± 12% by the Teicholze method. The valve echocardiographic analysis found that when excluding the values of EF in patients with mitral failure, the mean ± SD was 66.05 ± 11.74%, with no statistically significant difference when compared to the general population. Figure 2 shows the distribution of lesion severity.

Table 1. Relationship among gender, age and cause of valve disease

Table 2. Age x type of prosthesis.

5 – 27 years 28 – 55 years 56 – 82 years Total

Male R* NR† 29 14 38 30 09 38 76 82

Female R NR 43 06 79 17 13 23 135 46

Total 92 164 83 339

P value 0.018 0.000 0.069

5 – 27 years 28 – 55 years 56 – 82 years Total

Bioprótese 66 93 75 234

Metal 14 69 17 100

Total 80 162 92 334

P Value

0.000

* R - Rheumatic, † NR - Non-rheumatic

* R - Rheumatic, † NR - Non-rheumatic

Fig. 1 - Frequency of lesion type and site of involvement

Fig. 2 - Severity of injury

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Characteristics of the surgical procedure Among the operated patients, 267 (72.95%) underwent valve replacement, 27 (7.38%) underwent only valve repair, 67 (18.31%), both repair and replacement, five (1.36% ), other procedures such as aortic or mitral commissurotomy. Of the 334 patients who underwent valve replacement, 188 (56.29%) were of mitral valve, 89 (26.65%) aortic valve and 57 (17.06%) replacement. We used 234 (70.06%) bioprostheses, 121 (51.70%) in female patients and 113 (48.3%) males (P> 0.001). We used 100 (29.94%) prosthesis of metallic type, with a distribution of 55 (55%) for male patients and 45 (45%), female (P> 0.001) (Table 2). In a total of 94 patients who underwent valve repair, 56 (59.57%) were tricuspid, 21 (22.34%) mitral, six (6.38%) aortic valve, three (3.19 %) aortic and mitral and eight (8.52%) mitral and tricuspid valves.

secondary to left heart disease, and may be an indication of late diagnosis of valvular disease (Figure 1). As for combined valvular disease in clinical practice it is very common for the simultaneous involvement of aortic and mitral valves [7], as was found in our study, however, the number of patients with mitral and tricuspid simultaneous involvement was slightly higher when compared the number of patients with a concomitant mitral and aortic valve. In developing countries, rheumatic disease is the leading cause of heart disease from 5 to 30 years [6], and one of the two leading causes of death in young people, being costly to the health system and families [1]. The data from this study are consistent with the literature, and rheumatic disease was the leading cause of valvular heart disease, mainly affecting younger age groups (5-55 years) in both genders, implying a socioeconomic burden to society. A recent Brazilian study [8] showed that 22% of patients with rheumatic disease had school-age school failure, and that 5% of parents of patients lost their jobs due to absenteeism from work. Therefore, investment and effective control measures are urgent in our environment, minimizing their consequences, since the disease is clearly linked to socioeconomic conditions and the decline of rheumatic fever in developed countries is related to improving the quality of life, easy access to health care, special attention to primary prophylaxis of rheumatic disease, early diagnosis and treatment of infections of the upper airways [6].

DISCUSSION Valvular diseases are common in our environment, and rheumatic fever the main cause of valve lesions referred for cardiac surgery in developing countries. The dominance of etiologic profile and severity of clinical presentation often determine the choice of valve prostheses. The sample included patients of both genders and the results showed a predominance of females. The age ranged from 5 to 82 years, with a median of 41 years. The number of days of hospitalization ranged from 1 to 163, with a median of 24 days of hospitalization. We observed that more patients were coming from the inner cities of the state. We can infer social implications of these findings for public health, because it is a relatively young population, aged productive labor, providing a great economic impact calculated by years of productive life lost. Furthermore, these results imply higher costs for both the health system and to the families of patients who undergo limited resources and have extra transportation costs, meals and lodging, to move around in search of assistance in the capital the state, emphasizing here the lack of public referral centers in inner cities, able to diagnose and properly treat these patients, promoting overcrowding in specialized hospitals in the city of Salvador. The association between lesion type and site of commitment differs from pre-existing information in the literature. The stenosis of the aortic and mitral valves are responsible for two thirds of all valve diseases [2], however it was found in our study, more cases of failure or double lesion. Literature data on the prevalence of specific lesion sites and valve are scarce, precluding proper comparison with the sample in question, however, this study showed prevalence of tricuspid regurgitation, compared to the rates of mitral and aortic insufficiency. This finding may be due to a hemodynamic overload on the right ventricle [1], 214

Echocardiographic data In this study, the vast majority of patients seeking specialized health services showed moderate to severe injury (Figure 2), raising the possibility that these patients undergo surgery later, probably due to difficult access to adequate medical care in a timely manner. The delayed access to surgical treatment promotes greater involvement of the valve or subvalvular apparatus, and consequently, the worse the chances of success and limited surgical benefit in the long term [9]. Characteristics of the surgical procedure More than 30 years after the introduction of modern prostheses, the choice between biological and mechanical remains controversial [10]. Few randomized trials, controlled and with large numbers of patients to guide a definitive treatment of valvular heart disease. Most evidence of the international guidelines is C-level, i.e. based on studies of less impact [11]. For this reason, doctors are forced to draw conclusions and make recommendations based on incomplete information, limited data on clinical experience and common sense [12]. The choice between the types of prostheses in adults is determined primarily by assessing the risk of


Fernandes AMS, et al. - Impact of socio-economic profile on the prosthesis type choice used on heart surgery

anticoagulation related bleeding versus the risk of structural valve deterioration, but the clinical decisionmaking becomes increasingly challenging with the increase in life expectancy and the presence of comorbidities such as advanced age, congestive heart failure, coronary artery disease, pulmonary disease and renal failure [10]. In this study, the vast majority of patients underwent valve replacement (72.95%) and among the records of the type of prosthesis used, 70% were biological and only 30% metal. According to the recommendations set by the American College of Cardiology and American Heart Association, the main indication for valve replacement by a metallic one is the long survival of patients, as it presents a longer lasting [13]. Regarding the use of the bioprosthesis, its main indications are patients who cannot or do not accept treatment with blood thinners, reducing the risk of bleeding associated with such therapy, and/or patients older than 65 years [3]. At this age, there is a lower rate of deterioration in biological valves and increased risk of bleeding with anticoagulant therapy if mechanical valves were implanted. The use of biological prosthesis is considered inappropriate in adolescents during growth in patients with renal failure and hyperkalemia [13]. In this study, in all age groups, there was a significant predominance of the use of bioprostheses. It is noteworthy that, on average, in 10 years young subjects will undergo a new surgical procedure, in view of the life of this type of prosthesis [14]. However, these results can be attributed to a difficult access to health services for the population as a result of low socioeconomic status and provenance predominantly from the countryside of Bahia (Brazil), precluding adequate anticoagulation therapy, adherence and appropriate medical monitoring. On the other hand, the large percentage of female patients of reproductive age interfere in the choice and family planning as a result of anticoagulation [14], the risk of bleeding and potential teratogenic effects of coumarin. Moreover, the hypercoagulable state of pregnancy may favor thrombosis, the main complication of the use of metallic prostheses [15]. In relation to the mitral valve, this is the procedure of choice for mitral valve disease of degenerative cause, due to its lower rate of reoperation, thromboembolism and infection, when compared to mitral valve replacement. However, the repair in rheumatic disease is technically more difficult, and late results may be interfered by new exacerbations. The quality and long-term results in rheumatic disease are controversial and therefore a limiting factor is the evolving character of valve degeneration in this disease. However, the repair in rheumatic patients, when feasible from a technical standpoint and valve morphology, have satisfactory results in the long term, and must always appear as an alternative surgical [16,17].

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CONCLUSION The present study demonstrates that biological prostheses are preferentially used in younger individuals, possibly due to low socioeconomic status and high rates of women of reproductive age. Actions for intervention and prevention in public health to improve early access to control measures of streptococcal infections and epidemics, the efficiency of hospital services and postoperative followup can improve the choice of valve prostheses in this population.

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ORIGINAL ARTICLE

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Risk factors for low cardiac output syndrome after coronary artery bypass grafting surgery Fatores de risco para síndrome de baixo débito cardíaco após cirurgia de revascularização miocárdica

Michel Pompeu Barros de Oliveira Sá1, Joana Rosa Costa Nogueira1, Paulo Ernando Ferraz2, Omar Jacobina Figueiredo2, Wagner Cid Palmeira Cavalcante2, Thiago Cid Palmeira Cavalcante2, Hugo Thiago Torres da Silva2, Cecília Andrade Santos2, Renato Oliveira de Albuquerque Lima2, Frederico Pires Vasconcelos2, Ricardo de Carvalho Lima3

DOI: 10.5935/1678-9741.20120037 Abstract Objectives: Low cardiac output syndrome (LCOS) is a serious complication after cardiac surgery and is associated with significant morbidity and mortality. The aim of this study is to identify risk factors for LCOS in patients undergoing coronary artery bypass grafting (CABG) in the Division of Cardiovascular Surgery of Pronto Socorro Cardiológico de Pernambuco - PROCAPE (Recife, PE, Brazil). Methods: A historical prospective study comprising 605 consecutive patients operated between May 2007 and December 2010. We evaluated 12 preoperative and 7 intraoperative variables. We applied univariate and multivariate logistic regression analysis. Results: The incidence of LCOS was 14.7% (n = 89), with a lethality rate of 52.8% (n = 47). In multivariate analysis by logistic regression, four variables remained as independent risk factors: age ≥ 60 years (OR 2.00, 95% CI 1.20 to 6.14, P = 0.009), on-pump CABG (OR 2.16, 95% CI 1.40 to 7.08, P = 0.006), emergency surgery (OR 4.71, 95% CI 1.34 to 26.55, P = 0.028), incomplete revascularization (OR 2.62, 95% CI 1.32 to 5.86, P = 0.003), and ejection fraction <50%. Conclusions: This study identified the following

1. MD, MSc 2. MD 3. MD, MSc, PhD, ChM This work was carried out at Division of Cardiovascular Surgery of Pronto Socorro Cardiológico de Pernambuco - PROCAPE. University of Pernambuco (UPE), Recife, PE, Brazil.

RBCCV 44205-1374 independent risk factors for LCOS after CABG: age ≥ 60 years of off-pump CABG, emergency surgery, incomplete CABG and ejection fraction <50%. Descriptors: Risk factors. Cardiac output, low. Myocardial revascularization.

Resumo Objetivos: A síndrome de baixo débito cardíaco (SBDC) é uma complicação grave após cirurgias cardíacas, estando associada à significativa morbidade e mortalidade. O objetivo deste estudo é identificar fatores de risco para SBDC em pacientes submetidos à cirurgia de revascularização miocárdica (CRM), na Divisão de Cirurgia Cardiovascular do Pronto Socorro Cardiológico de Pernambuco - PROCAPE (Recife, PE, Brasil). Métodos: Estudo prospectivo histórico compreendendo 605 pacientes consecutivos operados entre maio de 2007 e dezembro de 2010. Avaliaram-se 12 variáveis pré-operatórias e sete variáveis intraoperatórias. Aplicaram-se análises univariada e multivariada por regressão logística.

Correspondence address: Michel Pompeu Barros de Oliveira Sá. Av. Eng. Domingos Ferreira, 4172/405 – Boa Viagem – Recife, PE, Brazil – ZIP Code: 51021-040 E-mail: michel_pompeu@yahoo.com.br Article received on October 27th, 2011 Article accepted on January 20th, 2012

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Abbreviations, acronyms & symbols AMI BMI CABG CI CK CK-MB COPD CPB CRM EF ICU ITA LCOS NYHA OR SBDC SPSS

Acute myocardial infarction Body mass index Coronary artery bypass grafting Confidence interval Creatine kinase Creatine kinase-MB fraction Chronic obstructive pulmonary disease Cardiopulmonary bypass Cirurgia de revascularização miocárdica Ejection fraction Intensive care unit Internal thoracic artery Low cardiac output syndrome New York Heart Association Odds ratio Síndrome de baixo débito cardíaco Statistical Package for Social Sciences

INTRODUCTION Low cardiac output syndrome (LCOS) is one of the most important complications after cardiac surgery [1] and regardless of the specific characteristics of studied groups, LCOS is associated with high mortality, reaching up to 38% [2], being considered the largest cause of mortality in coronary artery bypass grafting (CABG) surgeries performed in an emergency [1]. In addition to increased mortality related to LCOS, previous studies reported high rates of morbidity associated with this complication, such as increased incidence of pulmonary complications, myocardial infarction, stroke, renal failure and need for reoperation [2-6]. In addition to increased morbidity and mortality, patients who develop LCOS stay longer in ventilatory support, have a longer stay in intensive care unit and longer hospitalization [2,3], factors that are also reported as risk factors associated with higher mortality [1], with consequent increase of the economic impact of this entity [6]. The available data in the literature mainly refers to general cardiac surgery and recently there is a tendency to define risk factors for LCOS in specific subtypes of cardiac surgery such as aortic and mitral valve surgery with the definition of specific risk factors for each situation [2,3]. The identification of risk factors associated with the development of LCOS in coronary artery bypass surgery is essential to optimize pre-operative risk factors involved in strategies to improve myocardial protection and early intraoperative hemodynamic support [3], and set high-risk groups hemodynamically stable that may benefit from prophylactic use of intra-aortic balloon [6,7]. Therefore, the aim of this study is to identify risk factors for low cardiac output syndrome after CABG surgery. 218

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Resultados: A incidência de SBDC foi de 14,7% (n = 89), com taxa de letalidade de 52,8% (n = 47). Na análise multivariada por regressão logística, quatro variáveis permaneceram como fatores de risco independentes: idade ≥ 60 anos (OR 2.00, IC 95% 1,20 a 6,14, P = 0,009), CRM com circulação extracorpórea (OR 2,16, IC 95% 1,40 a 7,08, P = 0,006), cirurgia de emergência (OR 4,71, IC 95% 1,34 a 26,55, P = 0,028), CRM incompleta (OR 2,62, IC 95% 1,32 a 5,86, P = 0,003) e fração de ejeção < 50% (OR 1,87, IC 95% 1,17 a 3,98, P = 0,007). Conclusões: Este estudo identificou os seguintes fatores de risco independentes para SBDC após CRM: idade ≥ 60 anos, CRM com CEC, cirurgia de emergência, CRM incompleta e fração de ejeção < 50%. Descritores: Fatores de risco. Baixo débito cardíaco. Revascularização miocárdica.

METHODS Source population After approval by the ethics committee, in accordance with Resolution 196/96 (National Board of Health - Ministry of Health - Brazil) [8,9], we reviwed the records of consecutive patients undergoing CABG at our institution from May 2007 to December 2010. At first, we identified 647 patients eligible for the study. Forty-two were excluded due to lack of information from medical records, leaving 605 patients for data analysis, which complied with the minimum sample size calculated for the type of study required. Data collection was performed by trained staff (four people), and they did not know the purpose of the study (blind data collection). Sample size The sample was calculated from the work of Maganti et al. [3], which had as main objective the identification of predictors of LCOS after surgery for mitral valve surgery alone. It was selected the variable “emergency surgery”, which in this study had a frequency of 5.09% of LCOS among those non-exposed to this factor, with an odds ratio (OR) of 2.90. Considering á error as 5%, â error of 20%, and the study power as 80%, we obtained a minimum sample of 422 individuals for a cohort study. Study design It was a historical prospective study. The dependent variable was LCOS after the surgical procedure. This variable was categorized into yes or no. LCOS were considered with those who met the following criteria before discharge from first hospitalization in the intensive care unit immediatelly after surgery (built from studies about


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LCOS after mitral valve surgery [3], after aortic valve surgery [2] and patients with descompensated severe heart failure [10]): 1. Need for inotropic support with vasoactive drugs (dopamine 4 ì g/kg/min at least for a minimum of 12 hours and / or dobutamine) to maintain systolic blood pressure greater than 90 mmHg OR 2. Need for mechanical circulatory support with intraaortic balloon to maintain systolic blood pressure greater than 90 mmHg AND 3. Signs of impairment of body perfusion - cold extremities, hypotension, oliguria / anuria, lowered level of consciousness or a combination of these signs. The independent variables were divided into two categories: 1. Pre-operative factors: a. Age > 60 years; b. Gender (male or female); c. Obesity (body mass index > 30 kg/m2 - BMI); d. Hypertension (reported by a patient and/or use of anti-hypertensive medication); e. Diabetes (reported by a patient and/or use of oral hypoglicemic medication and/or insulin); f. Smoking (reported by a patient; active or inactive for less than 10 years); g. Chronic obstructive pulmonary disease - COPD (dyspnea or chronic cough AND prolonged use of bronchodilators or corticosteroids AND/OR compatible radiological changes - hypertransparency by hyperinflation and/or rectification of ribs and/or rectification diaphragmatic); h. Renal disease (creatinine > 2.3 mg/dL or pre-operative dialysis); i. Previous cardiac surgery; j. Ejection fraction (EF) < 50%; k. New York Heart Association (NYHA) functional class (I, II, III, IV); l. Recent acute myocardial infarction (AMI < 90 days).

surgically grafted coronary vessels; grafting of all the significantly stenotic coronary vessels was considered complete revascularization). We also assessed the following characteristics: postoperative incidence of cerebrovascular accident and renal failure, length of stay in intensive care unit (days) and hospital stay (days); outcome (survival or death).

2. Intra-operative factors: a. Emergency surgery (during acute myocardial infarction, ischemia not responding to therapy with intravenous nitrates, cardiogenic shock); b. Concomitant cardiac surgery; c. Use of internal thoracic artery (ITA); d. Number of bypass (1, 2, 3 or more); e. Use of cardiopulmonary bypass - CPB (on-pump or off-pump; according to the surgeon’s preference); f. Use of intraaortic baloon pump; g. Completeness of revascularization (comparing significantly stenotic vessels at cardiac catheterization with

Data analysis Data were stored in SPSS (Statistical Package for Social Sciences) program, version 15, from which calculations were performed with statistical analysis, and interpretation. The data storage was carried out in double-entry to validate and carry out analysis of data consistency, in order to ensure minimal error in recording information in software. Univariate analysis for categorical variables was performed with the chi-square test or Fisher’s exact test as appropriate. For continuous variables we used t-Student test. Verification of the hypothesis of equality of variances was performed using the Levene F test. Potential risk factors with P <0.05 in the univariate analysis were included in multivariate analysis in ascending order, which was performed by backward logistic regression. P values <0.05 were considered statistically significant. RESULTS Incidence Study population had a mean age of 62.00 years (± 10.06) and 58.7% (n = 355) were male and 41.3% (n = 250) were female. It was found an incidence of 14.7% (n = 89) of cases of LCOS after CABG. Univariate analysis Variables that were associated with increased risk of LCOS after CABG with P <0.05: were age > 60 years, emergency surgery, no use of ITA, EF < 50% and on-pump CABG. Data from the univariate analysis were shown in Tables 1 and 2. Multivariate analysis by logistic regression We identified the following independent risk factors for developing LCOS after CABG: age > 60 years (OR 2.00, 95% CI 1.20 to 6.14, P = 0.009), on-pump CABG (OR 2.16, 95% CI 1.40 to 7.08, P = 0.006), emergency surgery (OR 4.71, 95% CI 1.34 to 26.55, P = 0.028), incomplete revascularization (OR 2.62, 95% CI 1.32 to 5.86, P = 0.003), and ejection fraction <50% (OR 1.87, 95% CI 1.17 to 3.98, P = 0.007). Through specific tests, it was found that the model is well accepted (P <0.001) and showed a degree of explanation of 82.1% (Table 3). 219


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Table 1. Incidence of LCOS according to preoperative variables. LCOS Variable Yes No TOTAL % N % N % N

P Value

OR (95% CI)

Total Group

89

14.7

516

85.3

605

100

Age (years) < 60 > 60

18 71

8.0 18.7

208 308

92.0 81.3

226 379

37.4 62.6

0.001(1)*

1.00 2.66 (1.50 - 4.78)

Gender Male Female

49 40

13.8 16.0

306 210

86.2 84.0

355 250

58.7 41.3

0.452(1)

1,00 1.19 (0.76 - 1.87)

Obesity Yes No

9 80

9.5 15.7

86 430

90.5 84.3

95 510

15.7 84.3

0.177(1)

0.56 (0.25 - 1.21) 1.00

Hypertension Yes No

79 10

14.5 16.4

465 51

85.5 83.6

544 61

89.9 10.1

0.396(1)

0.87 (0.40 - 1.90) 1.00

Diabetes Yes No

38 51

16.2 13.7

196 320

83.8 86.3

234 371

38.7 61.3

0.399(1)

1.22 (0.77 - 1.92) 1.00

COPD Yes No

9 80

17.3 14.5

43 473

82.7 85.5

52 553

8.6 91.4

0.580(1)

1.24 (0.58 - 2.64) 1.00

Renal failure Yes No

8 81

17.4 14.5

38 478

82.6 85.5

46 559

7.6 92.4

0.593(1)

1.24 (0.56 - 2.76) 1.00

AMI < 90 days Yes No

39 50

13.9 15.4

242 274

86.1 84.6

281 324

46.4 53.6

0.591(1)

0,88 (0.55 - 1.42) 1.00

Smoke Yes No

41 48

14.0 15.4

252 264

86.0 84.6

293 312

48.4 51.6

0.629(1)

0.89 (0.56 - 1.44) 1.00

NYHA Class I/II III/IV

68 21

13.7 19.4

429 87

82.3 80.6

497 108

82.1 17.9

0.125(1)

1.00 0.66 (0.37 - 1.17)

EF < 50% Yes No

38 51

22.4 11.7

132 384

77.6 88.3

170 435

28.1 71.9

0.001(1)*

1.91 (1.30 - 2.79) 1.00

Previous cardiac surgery Yes 12 No 77

21.1 14.1

45 471

78.9 85.9

57 548

9.4 90.6

0.156(1)

1.63 (0.83 - 3.22) 1.00

(*): Significant difference at 5.0%; (1): Chi-square test; LCOS: low cardiac output syndrome; COPD: chronic obstructive pulmonary disease; AMI: acute myocardial infarction; NYHA: New York Heart Association; EF: ejection fraction; OR: Odds Ratio; CI: Confidence Interval

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Table 2. Incidence of LCOS according to intraoperative variables. LCOS Variable Yes No TOTAL N % N % N %

P Value

OR (95% CI)

Total Group

89

14.7

516

85.3

605

100

Use of ITA Yes No

64 25

12.9 22.7

431 85

87.1 77.3

495 110

81.8 18.2

0.009(1)*

0.50 (0.29 - 0.88) 1.00

Number of bypasses 1 2 3 or more

15 41 33

12.3 15.8 14.8

107 219 190

87.7 84.2 85.2

122 260 223

20.2 43.0 36.8

0,670(1)

1.00 1.28 (0.74 - 2.23) 1.20 (0.68 - 2.13)

Emergency surgery Yes No

6 83

50.0 14.0

6 510

50.0 86.0

12 593

2.0 98.0

0.004(2)*

6.14 (1.94 - 19.51) 1.00

Additional procedure Yes No

7 82

26.9 14.2

19 497

73.1 85.8

26 579

4.3 95.7

0.087(2)

2.23 (0.91 - 5.48) 1.00

Cardiopulmonary bypass On-pump Off-pump

69 20

20.6 7.4

266 250

79.4 92.6

335 270

55.4 44.6

< 0.001(1)*

3.24 (1.86 - 5.69) 1.00

Intraaortic baloon pump Yes 8 No 81

34.7 12.0

64 452

65.3 88.0

72 533

11.9 88.1

0.870(1)

0.60 (0.28 - 1.31) 1.00

Completeness of revascularization Complete Incomplete

11.8 29.9

448 68

88.2 70.1

508 97

84.0 16.0

< 0.001(1)*

1.00 3.22 (1.92 - 5.26)

60 29

(*): Significant difference at 5.0% (1): Chi-square test (2): Fisher’s exact test; LCOS: low cardiac output syndrome; ITA: internal thoracic artery; OR: Odds Ratio; CI: Confidence Interval

Table 3. Multivariate analysis by logistic regression Variable

Adjusted OR

P Value

Age > 60 years

2.00 (1.20 - 6.14)

0.009*

On-pump CABG**

2.16 (1.40 - 7.08)

0.006*

Emergency surgery

4.71 (1.34 - 26.55)

0.028*

Incomplete revascularization*** 2.62 (1.32 - 5.86)

0.003*

EF < 50%

0.007*

1.87 (1.17 - 3.98)

(*): Significant difference at 5.0%. Constant P < 0.001; (**): Compared to Off-pump CABG.; (***): Compared to Complete revascularization.; EF: ejection fraction; CABG: coronary artery bypass graft; OR: Odds Ratio; CI: Confidence Interval

Evolution and outcome Patients who developed LCOS after CABG stayed more days in the intensive care unit (8.45 ± 3.26 days versus 2.38 ± 1.21 days; P < 0.001) and longer hospital stay (21.87 ± 7.24 versus 10.54 ± 5.23; P < 0.001) compared with those who did not develop LCOS after CABG. Patients who developed LCOS after CABG presented higher rates of stroke (41.6% versus 3.5%; P <0.001) and renal failure (23.6% versus 5.8%; P <0.001) in comparison to the group that did not have postoperative LCOS. Forty-seven (52.8%) cases resulted in death. DISCUSSION Although some authors have reported that LCOS is a rare event after cardiac surgery using cardiopulmonary 221


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bypass with incidence rates reaching 0.1 to 2% [11,12], these numbers may be considerably higher in patients undergoing CABG surgery. Regarding the Brazilian data about LCOS after CABG, few studies have been published. A study evaluating 814 patients between 2002 and 2003 in Sao Paulo showed that LCOS was responsible for 54.2% of postoperative deaths and affected 16.1% of patients [13]. Similarly, a retrospective study of 546 patients undergoing CABG in Rio de Janeiro found LCOS as the most frequent postoperative complication [14]. The incidence of LCOS in our study was similar to other Brazilian series (14.7%). Advanced age has been documented as a risk factor for LCOS after heart surgery such as mitral valve surgery [3] and aortic valve surgery [2]. In patients undergoing aortic valve replacement, for example, the development of LCOS continues to be an important complication and has, as one of its risk factors, advanced age [2]. The same type of phenomenon was observed in our study, which specifically addressed CABG surgery. Misare et al. [15] demonstrated an age-dependent sensitivity to myocardial ischemia in an ovine model, introducing the term “senescent myocardium”, concluding that elderly patients may be at increased risk for myocardial injury because of their senescent myocardium, and developing higher rates of LCOS after CABG. Another risk factor for LCOS in our study was EF <50%. Low ventricular function is the most important predictor of postoperative morbidity and mortality [16]. Patients with poor ventricular function have a limited margin for myocardial protection, which makes patients experiment more intraoperative myocardial injury and develop LCOS after surgery [17]. However, the dysfunctional myocardium may not be irreversibly damaged and may be “stunned” or “hibernating”, so the role of myocardial protection in these patients may be to limit the extent of myocardial injury. We have demonstrated on-pump CABG as a risk factor for LCOS after surgery. This finding suggests a lower degree of myocardial injury in off-pump CABG. Some studies [18,19] show lower release of enzymes from myocardial injury in the postoperative period (CK, CK-MB, troponin T, parameters of myocardial injury) in patients undergoing off-pump CABG. The regional normothermic ischemia in off-pump CABG, the temporary interruption of coronary flow approached, seems to cause less myocardial injury compared to hypothermic global ischemia induced by cardioplegic arrest [20], which makes patients develop smaller rates of LCOS after CABG. We also have demonstrated incomplete revascularization as a risk factor for LCOS after surgery. We note that our rate of incomplete revascularization is the same as reported in the CABG-arm of ARTS-II trial, that it was 16.0% [21]. Someone might say that this observation of increased risk is due to the dicotomy of “on-pump vs. off-pump CABG” (also

related to the dicotomy “complete and incomplete revascularization”, creating a confounding field), but we must observe that this risk factor is independently associated with this complication, being on-pump CABG also an independent risk factor for this complication. So we must deduce that, independently of use or not use CPB, incomplete revascularization, per si, is prejudicial for myocardium. Beyond this aspect, some series have shown the absence of any such disparity of completeness of revascularization between off-pump and on-pump CABG, giving more reinforcement to the rationale that incomplete revascularization is an independent risk factor for LCOS [22]. We also observed emergency surgery as a risk factor for LCOS after CABG. Kim et al. [1] observed that emergency CABG (defined in their study as surgery done within 24h after diagnostic angiography) presents higher rates of mortality compared to elective CABG, pointing that LCOS after surgery as the major cause of death. Length of stay in intensive care unit (ICU) and hospital stay after cardiac surgery is associated with higher costs and may be correlated with an increased mortality, and some studies imply LCOS as a risk factor for this outcome. In a retrospective review of 3.523 patients undergoing CABG and/or valve surgery, multivariate logistic regression analysis showed that LCOS was an independent predictor of longer hospital stay and readmission to the ICU and a longer hospital stay [23]. We also observed that patients who developed LCOS in the postoperative period have average length of stay in ICU and hospital stay longer than patients without this complication. It was observed that 52.8% of patients who developed LCOS after CABG in our institution died. Other studies have shown that LCOS after cardiac surgery is associated with increased mortality [3,13], and a Brazilian study identified mortality associated with this complication very similar to that observed in our institution (54.2%) [3].

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CONCLUSION We identified the following risk factors for LCOS after CABG: age > 60 years, on-pump CABG, emergency surgery, incomplete revascularization and ejection fraction < 50%. Patients with LCOS after CABG present longer ICU and hospital length of stay, with high lethality rates.

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3. Maganti M, Badiwala M, Sheikh A, Scully H, Feindel C, David TE, et al. Predictors of low cardiac output after isolated mitral valve surgery. J Thorac Cardiovasc Surg. 2010;140(4):790-6. 4. Stamou SC, Hill PC, Dangas G, Pfister AJ, Boyce SW, Dullum MK, et al. Stroke after coronary artery bypass: incidence, predictors, and clinical outcome. Stroke. 2001;32(7):1508-13. 5. Landoni G, Bove T, Crivellari M, Poli D, Fochi O, Marchetti C, et al. Acute renal failure after isolated CABG surgery: six years of experience. Minerva Anestesiol. 2007;73(11):559-65. 6. Miceli A, Fiorani B, Danesi TH, Melina G, Sinatra R. Prophylactic intra-aortic balloon pump in high-risk patients undergoing coronary artery bypass grafting: a propensity score analysis. Interact CardioVasc Thorac Surg. 2009;9(2):291-4. 7. Christenson JT, Simonet F, Badel P, Schmuziger M. Evaluation of preoperative intra-aortic balloon pump support in high risk coronary patients. Eur J Cardiothorac Surg. 1997;11(6):1097-103. 8. Sá MP, Lima RC. Research Ethics Committee: mandatory necessity. Requirement needed. Rev Bras Cir Cardiovasc. 2010;25(3):III-IV. 9. Lima SG, Lima TA, Macedo LA, Sá MP, Vidal ML, Gomes AF, et al. Ethics in research with human beings: from knowledge to practice. Arq Bras Cardiol. 2010;95(3):289-94. 10. Ochiai ME, Cardoso JN, Vieira KR, Lima MV, Brancalhao EC, Barretto AC. Predictors of low cardiac output in decompensated severe heart failure. Clinics (Sao Paulo). 2011;66(2):239-44. 11. Ivanov J, Borger MA, Rao V, David TE. The Toronto Risk Score for adverse events following cardiac surgery. Can J Cardiol. 2006;22(3):221-7. 12. Sadeghi N, Sadeghi S, Mood ZA, Karimi A. Determinants of operative mortality following primary coronary artery bypass surgery. Eur J Cardiothorac Surg. 2002;21(2):187-92. 13. Bianco ACM, Timerman A, Paes AT, Gun C, Ramos RF, Freire RBP, et al. Análise prospectiva de risco em pacientes submetidos à cirurgia de revascularização miocárdica. Arq Bras Cardiol. 2005;85(4):254-61. 14. Oliveira TM, Oliveira GM, Klein CH, Souza e Silva NA, Godoy PH. Mortality and complications of coronary artery

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ORIGINAL ARTICLE

Rev Bras Cir Cardiovasc 2012;27(2):224-30

Heart defects treatment in Sergipe: propose of resources’ rationalization to improve care Tratamento das cardiopatias congênitas em Sergipe: Proposta de racionalização dos recursos para melhorar a assistência

Debora Cristina Fontes Leite1, José Teles de Mendonça2, Rosana Cipolotti3, Enaldo Viera de Melo4

DOI: 10.5935/1678-9741.20120038

RBCCV 44205-1375

Abstract Objective: This study aims evaluate the treatment of congenital heart disease conducted from 2000 to 2009. Methods: The sample consisted of all patients undergoing surgical correction for congenital heart disease for ten years in Sergipe, Brazil. The patients were operated in three hospitals located in the city of Aracaju, capital of the state of Sergipe (Brazil). The study was divided into two periods defined by the start date of centralization of surgery. The variables collected were: age, sex, postoperative diagnosis, destination, type of surgery and hospital where the procedure was performed and the classification RACHS -1. Results: In the period I, the estimate deficit of surgery was 69% decrease occurring in the period II to 55.3%. The postoperative diagnosis was more frequent closure of the interventricular communication (20.5%), closure of patent ductus arteriosus (20.2%) and atrial septal defect (19%). There was a statistically significant correlation between the expected mortality RACHS-1 and observed in the sample. The evaluation of RACHS-1 as a predictor of hospital mortality by ROC curve showed area of 0.860 95% CI 0.818 to 0.902 with P <0.0001.

Conclusion: The results of this study indicate that the centralization and organization of existing resources are needed to improve the performance of surgical correction of congenital heart diseases.

1. Master; Federal University of Sergipe, Coordinator of the Santa Isabel Maternity Neonatal Intensive Care Unit, Aracaju, Brazil. 2. PhD; Cardiovascular Foundation St. Francis of Assisi, Belo Horizonte, MG, Brazil. 3. PhD; University of São Paulo, Ribeirão Preto, Brazil. 4. Master; University of São Paulo, Ribeirão Preto, Brazil.

Correspondence address Débora Cristina Fontes Leite Rua Cláudio Manoel da Costa, s/n – Hospital Universitário. Núcleo de Pós-graduação em Ciências da Saúde – Aracaju, SE Brazil – Zip code: 49060-100 E-mail: deboraleite2006@hotmail.com

Work released at the Federal University of Sergipe, Aracaju, SE, Brazil.

Artigo received on October 28th, 2011 Article accepted on April 30th, 2012

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Descriptors: Heart defects, congenital. Cardiovascular surgical procedures. Health policy.

Resumo Objetivo: Avaliar o tratamento das cardiopatias congênitas realizadas de 2000 a 2009. Métodos: A amostra constituiu-se de todos os pacientes submetidos a correção cirúrgica para cardiopatias congênitas por dez anos em Sergipe, Brasil. Os pacientes foram operados em três hospitais localizados na cidade de Aracaju (SE, Brasil), capital do estado de Sergipe. O estudo foi dividido em dois períodos, definidos pela data do início da centralização das cirurgias. As variáveis coletadas foram: faixa etária, gênero, diagnóstico pós-operatório, destino, tipo de cirurgia e hospital em que foi realizado o procedimento e a classificação RACHS -1.


Leite DCF, et al. - Heart defects treatment in Sergipe: propose of resources’ rationalization to improve care

Abbreviations, acronyms & symbols CPB IAC IVC AC AVSD CI PDA RACHS-1 ROC SUS RV LV

cardiopulmonary bypass interatrial communication interventricular communication Aortic coarctation Atrioventricular Septal Defect Confidence Interval Patent ductus arteriosus Risk Adjustment for Congenital Heart Surgery Receiver-Operating Characteristic curve Unified Health System Right ventricle Left ventricle

INTRODUCTION The many advances made in cardiac surgery in the world last year [1] are often not accessible to people in developing countries [2]. Recently, in several developing countries, strategies were proposed for correction of congenital heart diseases, such as transfer of patients to developed countries, arrangement of cardiac surgeons’ trips to these countries or the creation of a local cardiovascular surgery program [3-6]. Brazil has several developments within cardiac surgery [7], but when comparing to other countries, shows a deficit of surgery for correction of congenital heart disease estimated at around 65%, depending on the region, with the northern region (93.5%) and Northeast (77.4%) with the major deficits [8-10]. In Sergipe, since 2007, through an agreement with the Health System all surgical correction of congenital heart disease are performed in an institution, which previously was distributed in three services. The aim of this study is to assess the treatment of congenital heart disease performed from 2000 to 2009, comparing the periods before and after the surgeries centralization. METHODS Sampling was performed consecutively, collected retrospectively, and all patients underwent surgical correction for congenital heart disease from January 1st, 2000 to December 31th, 2009 in Sergipe. The patients underwent surgery in three hospitals

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Resultados: No período I, a estimativa do déficit de cirurgia foi de 69%, ocorrendo decréscimo no período II para 55,3%. O diagnóstico pós-operatório mais frequente foi de fechamento de comunicação interventricular (20,5%), fechamento de canal arterial (20,2%) e da comunicação interatrial (19%). Houve correlação estatisticamente significativa entre mortalidade esperada pelo RACHS-1 e a observada na amostra. A avaliação do RACHS-1 como fator preditor da mortalidade hospitalar por meio da curva ROC demonstrou área de 0,860 IC 95% 0,818 a 0,902, com P < 0,0001. Conclusão: Os resultados deste estudo indicam que a centralização e a organização dos recursos existentes são necessárias para melhora no desempenho das correções cirúrgicas das cardiopatias congênitas. Descritores: Cardiopatias congênitas. Procedimentos cirúrgicos cardiovasculares. Política de saúde.

located in the city of Aracaju, capital of Sergipe State, being designated hospital 1, 2 and 3, for ethical reasons. Data from these patients were collected from the records of cardiopulmonary bypass (CPB), of compulsory filling, stored in single file, pertaining to all departments of cardiovascular surgery of Sergipe. The study was divided into two periods defined by the starting date of the agreement between SUS (Unified Health System-UHS) and the hospital 3, the period called I runs from January 1st, 2000 to December 31, 2006 and the period II from January 1st, 2007 to December 31th, 2009. The hospital is a charity institution that serves mostly UHS patients. The hospital 2, private, serves mostly patients from health plans and private, having an agreement with the UHS to perform heart surgery. Due to difficulties encountered in these hospitals for surgeries in pediatric patients, an agreement between UHS and the Hospital 3 was signed centralizing all procedures in the pediatric population in this service. The data collection of surgical correction was performed from July to December 2010. The variables collected were: age, gender, postoperative diagnosis, destination (discharge or death), type of surgery and hospital where the procedure was performed. The age range was established in the neonatal period (1-28 days old), 1st year of life (29 days to <1 year), children (from 1 year to 12 years) and adolescents and adults (over 12 years). We adopted the definition of the Brazilian Statute for Children and Adolescents establishing pediatric patients up to 12 years. For analysis of hospital mortality, child age was grouped with the adult, for statistical reasons, because there were no deaths in the latter. 225


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In the CPB record there was description of the preand postoperative diagnosis being considered in this study only the latter. From the postoperative diagnosis and the type of surgery were categorized in the classification of surgical risk for congenital heart disease according Risk Adjustment for Congenital Heart Surgery (RACHS-1) [11]. For death, we considered those occurring during the hospitalization and so-called hospital mortality. Were requested from the Health Secretary of Sergipe official birth certificate from 2000 to 2009. Due to difficulties in the diagnosis of congenital heart disease, we chose to assess the deficit of corrective surgery of congenital heart disease through estimates of disease incidence in relation to the number of live births, according to the methodology used in the literature [12]. We calculated the estimated deficit of surgery, where from the prevalence of the disease, 8 in 1000 live births, and the need for surgery in 80% of cases (7.2 per 1000 live births), we calculated the number of surgeries performed each year and subtracting the number of surgeries performed, it was the annual deficit. Categorical variables were described as single frequency (count) and percentages and their 95% CI (confidence interval for an estimated 95%) when appropriate. To assess the association between categorical variables we used the chi-square test. The analysis of expected mortality and by RACHS -1 and that observed in the sample were performed by Pearson correlation. For assessment of hospital mortality and RACHS-1 was constructed ROC curves and estimated the area under it. We considered the significance level as P <0.05, power 0.80 and the tests as two-tailed.

The statistical software used was SPSS version 17 for testing. This study was submitted to the Ethics in Research Involving Human Committee at the Federal University of Sergipe and approved in May 2010. RESULTS There was a deficit reduction of surgeries of 75.6% in 2000 to 54% in 2008, the year with lowest deficit. There was significant reduction of the surgery deficit over the years with P <0.0001. In relation to the periods of study, in the period I the estimated deficit of surgery was 69%, with decrease in period II to 55.3% (Table 1). In terms of age we observed a higher frequency of surgery in the age group 1-12 years, followed by over 12 years, with the smallest percentage in the neonatal period. Comparing the periods of the study, 15.5% of patients younger than one year underwent surgery in the period I and 20.3% in period II (Table 2). According to the postoperative diagnosis, the most frequent correction was closure of interventricular communication (IVC) (20.5%), closure of the ductus arteriosus (20.2%) and interatrial communication (IAC) (19%) (Table 3). In the classification of surgical risk for congenital heart defects by RACHS-1 there it was more common in categories 1 and 2, not occurring in category 5 in the ten years of follow-up (Table 4). Of the 932 patients undergone surgery, 77 (8.3% CI 95% 6.5 to 10.1) have evolved to death during hospitalization, and the neonatal age group had the highest rate of death (56.6% ) and death not occurring in patients over 12 years (Table 5).

Table 1. Estimated deficit of congenital heart disease surgeries per year in Sergipe Year 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009

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Number of births 40.331 39.560 36.614 36.793 35.604 37.576 37.330 35.820 36.637 35.096

Estimated need for correction 290 284 263 264 256 270 268 257 263 252

Number of surgeries performed 71 77 85 110 79 85 80 114 121 110

Surgery deficit (%) 219 (75.6) 207 (72.8) 178 (67.7) 154 (58.3) 177 (69.1) 185 (68.5) 188 (70.1) 143 (55.6) 142 (54) 142 (56.3)


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Table 2. Distribution of number of surgeries according to age by period in Sergipe Age 1 to 28 days 29d to 1 year >1 to 12 years >12 years Total

I 31 (5.3) 60 (10.2) 376 (64.2) 119 (20.3) 586 (100)

Period %cumulative 5.3 15.5 79.7 100

Table 3. Distribution of number of congenital heart disease surgeries according postoperative diagnostic in Sergipe from 2000 to 2009. Postoperative diagnosis Number (%) IVC 191 (20.5) PDA 188 (20.2) IAC 177 (19) Tetralogy of Fallot 115 (12.3) Pulmonary stenosis 38 (4.1) Pulmonary atresia 34 (3.6) Total AVSD 31 (3.3) Tricuspid atresia 22 (2.4) TGA 21 (2.3) AoCo 20 (2.1) TAPVD 12 (1.3) Double RV outflow tract 9 (1) Atrioventricular channel 9 (1) Single ventricle 9 (1) Aortic Stenosis 8 (0.9) Ebstein disease 7 (0.8) LV hiplopasia syndrome 6 (0.6) truncus arteriosus 5 (0.5) Double LV outflow tract 3 (0.3) Partial AVSD 2 (0.2) Others 11 (1.2) Total 932 (100) CIV = comunicação interventricular; PCA = persistência do canal arterial; CIA = comunicação interatrial; DSAV = defeito do septo atrioventricular; TGA = transposição das grandes artérias; CoAo = coartação da aorta; DATVP = drenagem anômala total das veias pulmonares; VD = ventrículo direito; VE = ventrículo esquerdo

II 22 (6.4) 48 (13.9) 209 (60.4) 67 (19.4) 346 (100)

%cumulative 6.4 20.3 80.4 100

Table 4. Distribution of hospital mortality of congenital heart disease according RACHS-1 classification by period RACHS-1 Period I (%) Period II (%) Category 1 1/249(0.4) 0/137(0) Category 2 21/250(8.4) 6/159(3.8) Category 3 7/45(15.6) 0/18(0) Category 4 26/39(66.7) 10/19(34.5) Category 6 3/3(100) 3/3(100)

Fig. 1 - Linear regression between expected and observed mortality by RACHS-1, confidence interval of 95%. Each RACHS-1 category in red

Table 5. Distribution of hospital mortality of congenital heart disease surgery by age group for pre- and postagreement in Sergipe. Period P Age group I(%) II(%) Total(%) 1 to 28 days 21/31 (67.7) 9/22 (40.9) 30/53(56.6) 0.05 29 d to 1 year 13/60(21.6) 4/48 (8.3) 17/108(15.7) 0.06 >1 to 12 years 24/376 (6.3) 6/209 (2.8) 30/585(27.7) 0.06 >12 years 0/119 (0) 0/67 (0) 0/186(0) Total 58/586 (9.8) 19/346 (5.4) 77/932(8.3) 0.02

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Fig. 2 - RACHS-1 risk classification as a predictor of hospital mortality (ROC) area. (CI-confidence interval)

Regarding the RACHS-1 risk classification the higher frequency of hospital mortality occurred in higher risk categories (4/6), however, with statistically significant difference between the periods, with reduced mortality in the period II, P <0, 0001 (Fig. 1). There was a statistically significant correlation (adjusted R² = 0.977 and P< 0.0001) between expected mortality by RACHS-1 and observed in the sample. The assessment of the RACHS-1 as a predictor of hospital mortality by ROC curve showed area of 0.860 95% CI 0.818 to 0.902 with P <0.0001 and statistically significant and comparable to that found in the literature [9] (Fig. 2]. DISCUSSION In the present study data, the number of surgeries over the years shows the increasing trend year by year from 2000 to 2003. Between 2004 to 2006 there was a decrease with increasing number of surgeries after 2007. This represents, numerically, the crisis experienced by the pediatric cardiac surgery between 2004 and 2006 which led to the centralization of infrastructure and human resources in the hospital 3, making productivity returned in 2003, Table 1. There was reduction in surgery deficit to 56% in period II, a value close to the estimated deficit in the Southeast region, site of the largest number of surgeries and centers for cardiovascular care [10]. Most surgeries occurred between age 1-12 years in two periods, being always the neonatal age group with the lowest ratio, followed by the age of 29 days to one year, according Table 2. This data serves as another indicator of deficit, because half of the repairs should 228

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have been performed up to the 1st year of life [13]. With the centralization of activities in the hospital 3, this increased proportion of children who underwent surgery before 1 year of 15.5% to 20.3% after the agreement, however, not statistically significant, probably due to sample size (Table 2). As described in the literature, 20% of patients undergoing repair of congenital heart disease were in the adult age group (table 2), a fact that did not change between periods (Table 4). This finding reinforces the deficit of surgical correction, since no patient had to postpone the procedure to adulthood, when some changes are already irreversible [12]. In period II a partnership with the Service of Mobile Emergency Care was organized, responsible for transport between units and hospitals for the early return of newborns to neonatal intensive care, generating turnover of intensive care beds and, consequently, increasing the number of surgeries. With respect to postoperative diagnosis, the frequency of correction of the interventricular septum defect was 20%, slightly below the described in the literature [14]. However, the frequency of IAC (19%) and PDA (20%) were well above those described in the literature [15,16]. Probably the surgeries deficit associated with the fact these more benign pathologies bear the delay in repair caused the cumulative frequency of these pathologies. Tetralogy of Fallot, with 12.3% of cases, was similar to the frequency found in the literature [17], also the Total Atrioventricular Septal Defect with 3.3% and Pulmonary Atresia with 3.6% of cases [18]. The aortic coarctation, with frequency in the literature of 5-8%, appears lower than expected with 2.1% of cases [19]. The pulmonary stenosis with 4.1% and transposition with 2.3% of cases were below the reported in the literature [18]. However, as the study approached surgical repairs and it is very serious diseases, probably the difference is the number of patients who progressed to death before surgical opportunity. The agreement with UHS reflected the reduction in hospital mortality of 9.8% in the pre-agreement to 5.4% in the post-agreement (Table 5), mainly with a reduction in the neonatal period, where there was statistical significance and in the other age groups there was no statistical significance probably due to the number of cases, but the total number of surgeries we realize the impact of the reduction with P <0.02. The association between higher volume of cases and better patient outcomes has been demonstrated for several surgical procedures and medical treatments, including surgery for children with congenital heart disease. In this context, centers with fewer than 70 procedures per year are considered low productivity, between 70 to 110 of


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productivity average and more than 110 procedures are considered as high productivity. The centers with higher productivity present better results [20,21]. The agreement between UHS and Hospital 3, which divides the study periods, promoted the centralization of the flow of patients with congenital heart disease in the pediatric population for this institution. The number of surgeries performed in the period I was of low productivity, because it was divided between the Hospital 1, which received more complex patients, and Hospital 2, which admitted patients with better prognosis. In period II, the surgeries of patients under 12 years were performed at Hospital 3, and the number of procedures already ranks as of average productivity. With increase in the number of surgeries per year the support team becomes well prepared, which for major surgery and the need for adequate infrastructure is of great importance, impacting the outcomes. Grouped by RACHS1 risk classification between the periods, it is clear the reduction in mortality, especially among the categories 2, 3 and 4, lower risk class, Table 5. Therefore, the centralization of material and human resources had as benefit the increasing number of surgeries, as well as the surgical outcomes with reduced hospital mortality rates, even when assessing the severity of cases. In linear regression between the RACHS-1 risk classification and hospital mortality it is clearly demonstrated that there are statistically significant correlation and that is a valid instrument for use in our country [9].

2. Yacoub MH. Establishing pediatric cardiovascular services in the developing world: a wake-up call. Circulation. 2007;116(17):1876-8.

CONCLUSION The outcomes of this study indicate that the centralization of both human resources and infrastructure are important for surgery of congenital heart disease, and the organization of existing resources is necessary to improve the performance of the service. ACKNOWLEDGMENTS We thank all congenital heart surgery team, the pediatric cardiologists, postoperative intensivists in Sergipe in the determination and tenacity facing clinical and socioeconomics challenges of our time.

REFERENCES 1. Lisboa LAF, Moreira LFP, Meija OV, Dallan LAO, Pomerantzeff PMA, Costa R, et al. Evolução da cirurgia cardiovascular no Instituto do Coração: análise de 71.305 operações. Arq Bras Cardiol. 2010;94(2):174-81.

3. Larrazabal LA, Jenkins KJ, Gauvreau K, Vida VL, Benavidez OJ, Gaitán GA, et al. Improvement in congenital heart surgery in a developing country: the Guatemalan experience. Circulation. 2007;116(17):1882-7. 4. Arzola RC, Sosa ES, Morejón CG, Casado JA, Lazo FV, Benavides AS, et al. Um nuevo enfoque de tratamiento integral del niño com cardiopatia em Cuba. Bol Oficina Saint Panam. 1994;117(3):275-6. 5. Gonzalez CL, Salazar BL, Salazar, VC. Cardiopatias congénitas en el Hospital México. Rev Med Costa Rica Centro Am. 2000;57(551):47-57. 6. Neirotti RA. Cardiac surgery: complex individual and organizational factors and their interactions. Concepts and practices. Rev Bras Cir Cardiovasc. 2010;25(1):VI-VII. 7. Stolf NA. Congenital heart surgery in a developing country: a few men for a great challenge. Circulation. 2007;116(17):1874-5. 8. Ministério da Saúde. MS/SVS/DASIS. Sistema de Informações sobre Mortalidade (SIM). Disponível em: http:// www.datasus.gov.br/catalogo/sim.htm. Acesso em 7/7/2010. 9. Ithuralde M, Neirotti R. Neonatal heart surgery: evaluation of risk factors. NeoReviews. 2011;12:252-9. 10. Pinto Jr VC. Avaliação da Política Nacional de Atenção Cardiovascular de Alta Complexidade com foco na cirurgia cardiovascular pediátrica [Dissertação de Mestrado]. Fortaleza: Universidade Federal do Ceará; 2010. 11. Jenkins KJ, Gauvreau K, Newburger JW, Spray TL, Moller JH, Iezzoni LI. Consensus-based method for risk adjustment for surgery for congenital heart disease. J Thorac Cardiovasc Surg. 2002;123(1):110-8. 12. Pinto Jr VC, Rodrigues LC, Muniz CR. Reflexões sobre a formulação de política de atenção cardiovascular pediátrica no Brasil. Rev Bras Cir Cardiovasc. 2009;24(1):73-80. 13. Atik E, Atik FA. Momento da indicação cirúrgica das cardiopatias congênitas cianogênicas. In Souza AGMR, Mansur AJ, eds. Socesp Cardiologia. 2º vol. São Paulo:Atheneu;1996. p.813-28. 14. Myague NI, Cardoso SM, Meyer F, Ultramari FT, Araújo FH, Rozkowisk I, et al. Epidemiological study of congenital heart defects in children and adolescents. Analysis of 4,538 cases. Arq Bras Cardiol. 2003;80(3):269-78. 15. Furlanetto BHS, Martins TC. Defeito do septo atrioventricular. In: Croti UA, Mattos SS, Pinto Jr VC, Aiello VD, eds. Cardiopatia e cirurgia cardiovascular pediátrica. São Paulo:Roca;2008.

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16. Silva LPRG, Bembom MC, Silva MFAG. Persistência do canal arterial. In: Croti UA, Mattos SS, Pinto Jr VC, Aiello VD, eds. Cardiopatia e cirurgia cardiovascular pediátrica. São Paulo:Roca;2008.

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program. Croat Med J. 2004;45(4):389-95.

17. Valente AS, Cirino CMF. Cardiopatia congênita no adulto. In: Croti UA, Mattos SS, Pinto Jr VC, Aiello VD, eds. Cardiopatia e cirurgia cardiovascular pediátrica. São Paulo:Roca;2008.

22. American College of Cardiology Foundation (ACCF). American Heart Association Methodology Manual for ACFF/ AHA Guideline Writing Committees: Methodologies and policies from the ACCF/AHA task force on practice guidelines. 2009. Disponível em: <www.americanheart.org/ presenter.jhtml?identifier3039683>. Acesso em 23/3/2010.

18. Mattos SS, Crotti UA, Pinto Jr VC, Aiello VD. Terminologia. In: Croti UA, Mattos SS, Pinto Jr VC, Aiello VD, eds. Cardiopatia e cirurgia cardiovascular pediátrica. São Paulo:Roca;2008.

23. Burstein DS, Rossi AF, Jacobs JP, Checchia PA, Wernovsky G, Li JS, et al. Variation in models of care delivery for children undergoing congenital heart surgery in the United States. Worid J Pediatr Congenit Heart Surg. 2010;1(1): 8-14.

19. Ebaid M, Afiune JY. Coarctação de aorta: do diagnóstico simples às complicações imprevisíveis. Arq Bras Cardiol. 1998;71(5):647-8.

24. Smith PC, Powell KR. Can regionalization decrease the number of deaths for children who undergo cardiac surgery? A theoretical analysis. Pediatrics. 2002;110(4):849-50.

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25. Mee RBB. Global challenges in education and training for congenital heart surgery: The Second Aldo Castañeda Lecture (2009). The second scientific meeting of the World Society for Pediatric and Congenital Heart Surgery at the Fifth world Congress of pediatric cardiology and Cardiac Surgery, Cairns, Queensland, Australia. Jun 21-26, 2009.

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ORIGINAL ARTICLE

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Six-minute walk test as a tool for assessing the quality of life in patients undergoing coronary artery bypass grafting surgery Teste de caminhada de seis minutos como ferramenta para avaliar a qualidade de vida em pacientes submetidos à cirurgia de revascularização miocárdica

Vanessa Cristina Baptista1, Luciana Campanatti Palhares2, Pedro Paulo Martins de Oliveira3, Lindemberg Mota Silveira Filho4, Karlos Alexandre de Souza Vilarinho5, Elaine Soraya Barbosa de Oliveira Severino4, Carlos Fernando Ramos Lavagnoli6, Orlando Petrucci7

DOI: 10.5935/1678-9741.20120039

RBCCV 44205-1376

Abstract Objective: Evaluate the quality of life in patients undergoing myocardial revascularization using the sixminute walk test. Methods: This is a prospective observational study with patients undergoing CABG. We recorded the following clinical variables: the six-minute walk test and the SF36 test. The patients were evaluated at the preoperative time and at 2 months of the postoperative period. Patients were evaluated preoperatively and divided into two groups according to the 6-minute walking test: the group with a walking course of >350 meters and the group with a walking course of less than 350 meters at the preoperative time. Results: The study population included 87 patients. Mean age was similar in both groups (59 ± 9.5 years vs. 61 ± 9.3 years, respectively, P = 0.24). Distances walked were significantly longer in the group with a walking course of

>350 meters compared to the group with a walking course of <350 meters after 2 months of operation (436 ± 78 meters vs. 348 ± 87 meters; P <0.01). The quality of life was lower in the group with a walking course of <350 meters compared to the group with a walking course of >350 meters in the preoperative period in the following domains: functional capabilities, limitations due to physical aspects, overall health feelings, vitality, and social aspects. Quality of life improved after two months in both groups. Conclusions: The six-minute walk test at the preoperative time is associated with the quality of life after two months of coronary artery bypass grafting. In overall, quality of life has improved in all patients. The improvement in the quality of life was greater in those patients with a walking course of >350 meters at the preoperative time.

1. Physical Therapist, University of Campinas (UNICAMP), Campinas, SP, Brasil. 2. Doctorate Degree in Clinical Medicine, Unicamp’s Teaching Hospital (Hospital das Clínicas), Campinas, SP, Brazil. 3. Doctorate Degree, assistant professor, Surgery Department, Unicamp’s School of Medical Sciences, Campinas, SP, Brazil. 4. Doctorate Degree, assistant physician, Surgery Department, Unicamp’s School of Medical Sciences, Campinas, SP, Brazil. 5. Master’s Degree, assistant physician, Surgery Department, Unicamp’s School of Medical Sciences, Campinas, SP, Brazil. 6. Assistant Physician, Surgery Department, Unicamp’s School of Medical Sciences, Campinas, SP, Brazil. 7. Postdoctorate Degree, assistant professor, Unicamp’s School of Medical Sciences, Campinas, SP, Brazil.

This study was carried out at the Surgery Department, in the Discipline of Cardiac Surgery, Unicamp’s School of Medical Sciences, Campinas, SP, Brasil.

Descriptors: Physical therapy modalities. Indicators of quality of life. Quality of life. Myocardial revascularization.

Correspondence address: Vanessa Cristina Baptista Rua José Duarte, 220 / 2 – Arruamento Fain José Feres – Campinas, SP, Brasil – CEP 13084-586 E-mail: vanbap@hotmail.com Foster by São Paulo Research Foundation – FAPESP Article received: on September 21st, 2011 Article accepted on February 5th, 2012

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Abbreviations acronyms & symbols ECC/CPB DM SD LVEF AMI BMI QOL MR/CABG SF36 6MWT LV MV

Extracorporeal Circulation/Cardiopulmonary bypass Diabetes mellitus Standard Deviation Left Ventricular Ejection Fraction Acute Myocardial infarction Body Mass Index Quality of Life Myocardial Revascularization/ Coronary Artery Bypass Grafting The Medical Outcomes Study 36 – Item Short Form Health Survey Six-Minute Walk Test Left Ventricle Mechanical ventilation

Resumo Objetivo: Avaliar a utilidade do teste de caminhada de seis minutos como indicador prognóstico de qualidade de vida em pacientes submetidos a revascularização do miocárdio. Método: Estudo prospectivo observacional em pacientes submetidos a operação de revascularização do miocárdio. Foram avaliadas as características clínicas, teste de caminhada de seis minutos (TC6) e questionário para avaliação de qualidade de vida, o questionário SF-36. Os

INTRODUCTION Thoracic/Cardiac surgery comprises a series of changes in patients’ lives. As it is an invasive procedure, it causes pain and anxiety in both patients and family. In addition, thoracic/cardiac surgery is associated with morbidity and mortality. It includes chronic physical and functional disabilities, that impact on quality of life (QOL) of these patients. The coronary artery bypass grafting (CABG) aims to increase survival, to relieve symptoms of myocardial ischemia, to improve ventricular function, to prevent myocardial infarction, to recover the patient physically, psychologically, and socially, as well as to prolong patient’s life and QOL [1-6]. The improvement of QOL is considered as an outcome to be reached after care practices, as well as public policy actions in health promotion and disease prevention [6]. A melhoria da QV é considerada como um desfecho a ser obtido após práticas assistenciais, bem como nas políticas públicas nas ações de promoção à saúde e de prevenção de doenças [6]. The evaluation and measurement of QOL are important in the process of clinical decision making and determination of therapeutic benefits, a perception the patient has about his/her illness. Besides, it also provides a way to evaluate patient survival [7]. Several reports have demonstrated improvement in the QOL postoperative period of thoracic/ 232

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pacientes foram avaliados no pré-operatório e divididos em dois grupos, conforme a distância percorrida no TC6: grupo que caminhou mais de 350 metros e grupo que caminhou menos de 350 metros. Resultados: Foram incluídos no estudo 87 pacientes. A idade média semelhante em ambos os grupos (59 ± 9,5 anos vs. 61 ± 9,3 anos; P = 0,24). Os pacientes do grupo > 350 metros caminharam mais no TC6 após dois meses de operação (436 ± 78 metros vs. 348 ± 87 metros; P<0,01) quando comparado ao grupo < 350 metros. Observamos que a qualidade de vida era inferior no grupo < 350 metros em relação ao grupo > 350 metros, no período pré-operatório, nos domínios: capacidade funcional, aspectos físicos, estado geral de saúde, vitalidade e aspectos sociais. A qualidade de vida melhorou após dois meses, em ambos os grupos. Conclusões: O TC6 no pré-operatório tem correlação com a qualidade de vida após dois meses de revascularização do miocárdio. A qualidade de vida melhorou de forma geral em todos pacientes, sendo maior a melhora da qualidade de vida naqueles que caminharam menos que 350 metros no pré-operatório. Descritores: Modalidades de fisioterapia. Indicadores de qualidade de vida. Qualidade de vida. Revascularização miocárdica.

cardiac surgery compared to the preoperative period [810]. Thus, objective ways to evaluate the QOL are important in the overall treatment of patients. The six-minute walk test (6MWT) is a tool to measure QOL, once its performance may reflect the ability to perform daily activities [11]. This test has been correlated as a prognostic marker in various situations, especially in patients with pulmonary embolism [12,13], for example. The 6MWT is widely used in cardiac rehabilitation in several categories of patients, such as after heart surgery, myocardial infarction, and chronic heart failure. It is also an indicator of the functional state of these medical situations [14]. The objective of this study was to evaluate the usefulness of the 6MWT as a prognostic indicator of QOL in patients undergoing Coronary Artery Bypass Grafting surgery. METHODS Design and Setting We conducted a research of prospective observational analysis. We studied 97 patients undergoing elective CABG surgery with or without another associated surgical procedure. We included in the study patients admitted from February 2009 to April 2011. The study was approved by the Research and Ethics Committee of the Unicamp’s School of Medical Sciences (CEP-FCM-UNICAMP), under


Baptista VC, et al. - Six-minute walk test as a tool for assessing the quality of life in patients undergoing coronary artery bypass grafting surgery

Rev Bras Cir Cardiovasc 2012;27(2):231-9

Opinion Report Nr. 718/2008, CAAE: 05770146000-0. Patients were evaluated in two periods of time: the preoperative period and the postoperative period (two months after the operation). All patients were treated by the same surgical and physical therapist team. There were no changes during the treatment before and after surgery that could interfere with the postoperative outcome. Inclusion criteria were age between 18 and 90 years; elective CABG surgery with or without associated surgical procedures, and patients who agreed to participate by signing the written consent form. Exclusion criteria were patients undergoing other surgical procedures without associated CABG, unstable angina, or those with medical contraindications to 6MWT.

Statistical Analysis Continuous variables are expressed as mean ± standard deviation. Discrete variables are expressed as frequency and percentage. Both groups were compared when variables were normally distributed. The Student’s t test or the Mann-Whitney test was used to compare the groups, as appropriated. Discrete variables were assessed using the Chi-square test. In order to assess the different domains of the SF-36 questionnaire, we performed a partial correlation analysis two after the operation using the distance walked in the 6MWT before the operation. Next, we performed a correlation analysis. The partial correlation analysed the following variables: age, gender, body mass index (BMI) and the use of beta-blockers preoperatively. Statistical analysis was performed using SPSS for Mac version 18 (SPSS, Chicago, IL, USA).

Measurement of the QOL In order to perform the measurement of QOL, we used The Medical Outcomes Study 36 – Item Short Form Health Survey (SF36). This is a multidimensional questionnaire, consisting of 36 questions covering eight domains. It aims to reflect the impact of disease on patients’ lives in a wide range of populations [8]. The domains evaluated by the questionnaire are: physical functioning, role-physical, bodily pain, general health, vitality, role-emotional, social functioning, and mental health. The questions are based on the perception the patients have of their health status over the past four weeks. In order to reach the results in each domain, the questionnaire analyzes the score obtained on each question, which is then transformed into a scale from zero (lowest score) to 100 (highest score) [15]. The questionnaire was administered by interview on two occasions: preoperatively, and two months after the operation. The Six-Minute Walk Test (6MWT) The 6MWT is a submaximal test that measures the distance the patient can quickly walk on a flat surface in a period of 6 minutes [13]. The test was performed preoperatively and two months after the operation, following the guidelines of the American Society of Thoracic Surgery [16]. Briefly, the test was interrupted at the patient request, and the distance walked was measured. Analysis Groups Patients were divided into two groups based on the distance walked in the 6MWT in the preoperative period. We used a cutoff value of 350 meters. It is the closest value to the average distance walked preoperatively for all patients. In the literature, it is considered a representative value of good or poor functional capacity [17-19]. Thus, data from both groups of patients was compared: the group with a walking course of >350 meters and the group with a walking course of <350 meters. In this way, we were able to compare both groups.

RESULTS Ninety-seven patients were initially included in the study. Ten of these subjects were excluded because three died and seven due to lack of adherence to medical evaluations. The final pool of patients comprised 87 patients. Table 1 shows demographics data of patients. In demographic variables, we observed differences between the groups only in relation to gender. There were more male patients within the group with a walking course of >350 meters and more women within the group with a walking course of <350 meters. According to the EuroScore, all study patients were of low and medium risk with no difference between groups.

Table 1. Demographic Data. P > 350 meters < 350 meters Variables n=52 n=35 Age (years) 59 ± 9 61 ± 9 0.24 Gender <0.01 M 43 (83%) 15 (43%) F 9 (17%) 20 (57%) DM 19 (36%) 18 (52%) 0.24 Smoking 16 (31%) 9 (26%) 0.78 BMI (kg/m2, mean/SD) 29 ± 5 27 ± 3 0.12 EuroSCORE 2.3% ± 1.3% 2.9% ± 2.8% 0.19 56 ± 13 0.07 LVEF (mean/SD) 61 ± 13 26 (74%) 0.64 Previous AMI 35 (67%) M = male; F = female; SD = standard deviation; BMI = body mass index; DM = diabetes mellitus. LFEF = Left ventricular ejection fraction; AMI = acute myocardial infarction. Data are expressed as mean ± standard deviation. P: Significance level. Group total as expressed as percentage (%)

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Baptista VC, et al. - Six-minute walk test as a tool for assessing the quality of life in patients undergoing coronary artery bypass grafting surgery

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Table 2. Drugs used in both pre and postoperative period. > 350 meters Drugs n = 52 Pré Pós Beta-blocker 42 (81%) 41 (79%) Diuretic 16 (31%) 23 (45%) Platelet antiaggregant 6 (12%) 51 (98%) Statins 45 (87%) 48 (92%) Angiotensin conversing enzyma inhibitor 15 (29%) 28 (54%) Nitrate 15 (29%) 1 (2%) Calcium channel blocker 5 (10%) 11 (21%) Vasodilator 3 (6%) 3 (6%) Anticoagulant 11 (21%) 3 (6%) Angiotensin II receptor blocker 2 (4%) 3 (6%) Antiarrhythmic 1 (2%) 4 (8%) Digitalis 1 (2%) 1 (2%)

< 350 meters n = 35 Pré Pós 28 (80%) 26 (74%) 15 (48%) 23 (65%) __ 35 (100%) 29 (83%) 32 (91%) 9 (26%) 16 (45%) 15 (48%) __ 6 (17%) 15 (48%) 6 (17%) 2 (6%) 13 (37%) 1 (3%) 3 (9%) 7 (20%) 1 (3%) 2 (6%) __ 1 (3%)

P Pré 0.85 0.35 0.09 0.86 0.93 0.26 0.47 0.17 0.13 0.64 0.67 0.84

Pós 0.81 0.08 0.84 0.79 0.59 0.84 0.05 0.64 0.90 0.08 0.94 0.65

Data are expressed as mean ± standard deviation. P: significance level. Group total as expressed as percentage (%). Beta-blocker = propanolol, atenolol, carvedilol. Diuretic = furosemide, hydrochlorothiazide and spironolactone. Platelet antiaggregant = acetylsalicylic acid and clopidogrel. Statins = simvastatin, pravastatin. Angiotensin conversing enzyma inhibitor = captopril e enalapril. Nitrate = isosorbide mononitrate and propatylnitrate. Calcium channel blocker = amlodipine, diltiazem, verapamil and nifedipine. Vasodilator = hydralazine and methyldopa. Anticoagulant = warfarin, enoxaparin and unfractionated heparin. Angiotensin II receptor blocker = losartan potassium. Antiarrhythmic = amiodarone. Digitalis = digoxin e deslanoside. Drugs were not controlled as to dose and frequency of administration

Table 3. Intra- and postoperative data. Procedures performed CABG CABG with LV aneurismectomy CABG with valvar replacement CABG with LV aneurismectomy + valvar replacement CABG + septal exclusion Surgery duration (minutes) MV time (minutes) CABG time (minutes) Aortic clamping time (minutes) Ischemia time (minutes)

> 350 meters n = 52 43 (83%) 5 (10%) 3 (6%) 1 (2%) __ 220 ± 33 512 ± 330 80 ± 22 63 ± 21 35 ± 12

< 350 meters n = 35 29 (83%) 2 (6%) 1 (3%) 2 (6%) 1 (3%) 222 ± 32 507 ± 251 74 ± 24 58 ± 21 31 ± 11

P

0.53

0.64 0.60 0.18 0.23 0.44

MR/CABG = Myocardial Revascularization/Coronary Artery Bypass Grafting; LV = Left Ventricle; MV = mechanical ventilation; Extracorporeal Circulation/Cardiopulmonary bypass. Data are expressed as mean ± standard deviation. P: Significance level. Group total as expressed as percentage (%)

Table 2 shows the drugs used pre and postoperatively, such as beta-blocker, diuretic, digitalis, angiotensin II conversing enzyme, calcium channel blocker, statin, platelet antiaggregant, nitrate, vasodilator, anticoagulant, angiotensin II receptor blocker and antiarrhythmic. Table 3 shows details on the operation data. It was verified the type of surgery, duration of mechanical ventilation, cardiopulmonary bypass time, ischemia time and aortic clamping. Among the complications found in the postoperative period are wound dehiscence of the lower limb, acute 234

pulmonary edema, hemothorax, atrial fibrillation, pleural effusion and pneumonia (Table 4). Table 5 shows the partial correlation with the distance walked in the 6MWT preoperatively, and the data from the SF-36 QOL questionnaire postoperatively. There was a positive correlation with physical functioning (P <0.01), pain (P = 0.04) and vitality (P = 0.01) postoperatively. Data on 6MWT are shown in Figure 1. There is an improvement in the distance walked in the postoperative period only in the group with a walking course of <350 meters (233 ± 106 meters vs. 348 ± 87 meters, P = <0.01) and


Baptista VC, et al. - Six-minute walk test as a tool for assessing the quality of life in patients undergoing coronary artery bypass grafting surgery

Table 4. Postoperative complications. Postoperative complications Dehiscence of lower limb incision Acute pulmonar edema Hemothorax Atrial fibrillation Pleural efusion Pneumonia

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> 350 meters n = 52 2 (4%) 1 (2%) 1 (2%) 1 (2%) __ __

< 350 meters n = 35 __ 1 (3%) __ 1 (3%) 1 (3%) 1 (3%)

P 0.34 0.80 0.56 0.39 0.80 0.38

P: Significance level. Group total as expressed as percentage (%)

Table 5. Correlation between the walk questionnaire postoperatively. Controlled Variables Idade, sexo, IMC e beta-blocker Physical functioning Role-physical Pain General health Vitality social functioning Role-emotional mental health

test vs. the SF-36 Distance walked (m)* r= 0.29 (P<0.01) r= 0.11 (P= 0.31) r= 0.22 (P = 0.04) r= 0.05 (P = 0.59) r= 0.27 (P = 0.01) r= 0.14 (P = 0.18) r= -0.04 (P = 0.67) r= 0.06 (P = 0.53)

r = correlation. P = Significance level. *Distance walked preoperatively in the six-minute walk test

in the group with a walking course of >350 meters (428 ± 47 meters vs. 436 ± 78 meters, P = 0.40). When comparing the distance walked between groups, it was observed that the group with a walking course of >350 meters walked longer in both phases. With regard to the SF-36 QOL questionnaire, it was observed a significant improvement in QOL in both groups. The group with a walking course of <350 meters presented a marked improvement. The group with a walking course of >350 meters showed improvement in the following domains: pain, general health, vitality, social functioning and mental health. The group with a walking course of <350 meters presented improvement in the following domains functional capacity, role-physical, pain, general health, vitality, social functioning, role-emotional, and mental health. When comparing data from SF-6 between groups (>350 meters vs <350 meters), there was a difference in almost all domains, both preoperatively and postoperatively (Table 6). DISCUSSION CABG surgery is a complex operation, and it has an impact on QOL. Changes in QOL may lead to organic, emotional, behavioral, social, and functional alterations. The application of instruments regarding physical or mental

Fig. 1 - Six-minute walk test. Pre and postoperative distance walked in both groups. Data are expressed as mean ± standard deviation. We observed an improvement in the distance walked in the postoperative period only in the group with a walking course of <350 meters (233 ± 106 meters vs. 348 ± 87 meters, P <0.01) vs the group with a walking course of >350 meters (428 ± 47 meters vs. 436 ± 78 meters, P= 0.40). *P<0.01.

evaluation is useful to measure possible changes in QOL after certain medical interventions [20]. The SF-36 questionnaire proved to be useful for the assessment of QoL in this study. In the present study, we found that QOL 2 months after the surgery is associated with 6MWT in the preoperative period. In general, patients who completed a walking course of more than 350 meters preoperatively had better QOL 2 months after surgery. We have also demonstrated that patients who walked less than 350 meters in the 6MWT preoperatively showed improvement in all domains of the SF-36 questionnaire. Nevertheless, these patients still had a QOL inferior to the patients who walked more than 350 meters in the preoperative period in four domains of the SF-36 questionnaire. 235


Baptista VC, et al. - Six-minute walk test as a tool for assessing the quality of life in patients undergoing coronary artery bypass grafting surgery

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Table 6. Data concerning the quality of life questionnaire SF-36: comparison of preoperative data vs postoperative data in each group and the difference between the groups. Domains Physical functioning

Preoperative

>350 meters (n=52) 59 ± 29

<350 meters (n=35) 22 ± 25

P >350 meters vs.< 350 meters <0.01

Postoperative

52 ± 20

33 ± 16

<0.01

0,16

0,02

Preoperative

59 ± 34

44 ± 31

0.03

Postoperative

64 ± 25

65 ± 22

0.83

0,44

<0,01

Preoperative

54 ± 35

43 ± 35

0.17

Postoperative

87 ± 20

81 ± 24

0.17

<0,01

<0,01

Preoperative

77 ± 19

64 ± 19

<0.01

Postoperative

95 ± 9

93 ± 11

0.42

P

<0,01

<0,01

Preoperative

78 ± 15

65 ± 20

<0.01

Postoperative

87 ± 9

75 ± 17

<0.01

P

<0,01

0,01

Preoperative

83 ± 22

64 ± 32

<0.01

Postoperative

94 ± 12

85 ± 18

0.01

<0,01

<0,01

Preoperative

75 ± 31

62 ± 32

0.06

Postoperative

81 ± 23

79 ± 24

0.65

0,14

<0,01

Preoperative

74 ± 15

70 ± 18

0.25

Postoperative

86 ± 11

79 ± 14

<0.01

<0,01

0,01

P Role-physical

P Pain

P General health

Vitality

Social functioning

P Role emotional

P Mental health

P

We could not perform a second evaluation two months after the operation in seven patients. In this study, we also observed three deaths in the perioperative period. The use of the 6MWT proved to be effective. It allows evaluating the patients with a walking course of more or less than 350 meters. This cutoff value used for group analysis was based on several reports found throughout the literature. Bittner et al. [18], studying patients with chronic heart 236

failure and the 6MWT, observed that patients with a walking course of less than 350 meters had a higher risk of death compared with those with a walking course of than 450 meters in the same walk test. In order to assess prognosis and mortality, other authors also used a distance of 350 meters as a cutoff point for patients with chronic obstructive pulmonary disease, chronic heart failure, and pulmonary hypertension [21,22]. Opasich et al. [14] studied patients undergoing cardiac


Baptista VC, et al. - Six-minute walk test as a tool for assessing the quality of life in patients undergoing coronary artery bypass grafting surgery

Rev Bras Cir Cardiovasc 2012;27(2):231-9

surgery. They found that the distance walked in the 6MWT and a left ventricular ejection fraction greater than 50% in patients aged 61 to 70 years was on the averaged 330 ± 98 meters for men and 255 ± 93 meters for women. Finally, in our sample, the average distance walked was 349 ± 122.8 meters. For these reasons, we should use the value of 350 meters as a pattern of analysis of the patients. The use of the cutoff value of 350 meters allowed an objective analysis of both groups of patients and their associations with QOL in the postoperative period two months after surgery. In the present study, we observed that the preoperative 6MWT was associated with QOL after two months of the operation in patients undergoing CABG. This association was positive in the following domains: physical functioning (P <0.01), pain (P = 0.04), and vitality (P = 0.01). We used the partial correlation to control age, sex, BMI, and the use of beta-blockers because these variables could affect the distance walked. This mathematical feature allows us to observe the association between 6MWT and QOL without taking into account the variables mentioned previously [11,19]. These findings are similar in patients who underwent the 6MWT during cardiac rehabilitation after acute myocardial infarction [23]. In this study, Hamilton & Haennel [23] observed that patients undergoing cardiac rehabilitation had a positive correlation of functional capacity, pain, general health, vitality, social functioning, and mental health and the 6MWT. Another finding of practical interest is that the group with a walking course of less than 350 meters showed an increase in distance walked after two months of the operation. Therefore, has its functional capacity improved (233 ± 106 meters vs. 348 ± 87 meters, P <0 01). Both study groups showed improvement in QoL two months after of the operation. The group with a walking distance of less than 350 meters showed an improvement in eight domains of the SF-36 questionnaire, while the group with a walking distance of more than 350 meters showed an improvement in the following domains: pain, general health, vitality, social functioning, and mental health two months after the operation. Patients with a short walking course in the preoperative period benefited most from the operation when considering QOL. We also observed an improvement in functional capacity only in the group with a walking course of less than 350 meters. In the preoperative period, these patients were weaker and when they had to answer the questions regarding the physical functioning domain, such as climbing stairs, sweep the house, bathing, crouching, walk a block and even up to one kilometer in the last four weeks, many of them could not perform most of these activities without getting tired, or even could not do the activities at all.

In the postoperative period, the patients reported an improvement to perform these activities. The group with the walking course of more than 350 meters had a higher score than the group with a walking course of less than 350 meters (P <0.01) in the physical functioning domain, a fact that reflected in their daily activities. In the preoperative period, patients were more anxious and nervous and this reflected in the assessment of QoL. Postoperatively, patients were less nervous and/or anxious and when they answered the SF-36 questionnaire, they reported an improvement in almost all domains of the questionnaire. For some authors, the patients experience a gradual increase of QoL after one, three, and six months after the operation [9,10,19,24,25]. Both groups improved their physical and mental health two months after the operation. The improvement was more evident in patients who were more debilitated preoperatively, i.e., the group with a walking course of less than 350 meters. The improvement of physical and mental components found in this study and assessed through the SF-36 questionnaire is consistent with previous studies in which patients were evaluated within 12 months after the operation [10.26]. Nogueira et al. [27], studying a pool of patients similar to those in our study, compared the use or not of CPB in CABG surgery. They observed no differences in patients who did or did not undergo cardiopulmonary bypass. Nevertheless, they observed a consistently, progressively, and continuously improvement of the QoL [27]. These findings are similar to the present report. However, we did not evaluate patients who underwent CABG without cardiopulmonary bypass. Furthermore, we believe these findings are similar to that found in this work using the 6MWT. There are reports in the literature regarding the differences in QoL when analyzing the gender of patients. The QOL is lower in women compared with men six months after cardiac surgery [9,23]. In the present study, we observed more men in the sample. The individual analysis by gender was not performed due to the limitations of the sample. Both groups showed an improvement in pain after the operation, which reflected in QOL, once the pain ends up limiting the activities of daily living, physical health, mental, and social health of the patients. When patients were asked about the pain, they generally referred to the pain of angina pectoris. However, at the time of the evaluation, the patients did not have a clinical setting of unstable angina. This is due to the format of the questionnaire. The questions were design to know whether the patient felt pain in the last four weeks, which is the period of time the symptoms appeared. In a recent study evaluating QOL, the authors observed an improvement in patients undergoing cardiac surgery after 237


Baptista VC, et al. - Six-minute walk test as a tool for assessing the quality of life in patients undergoing coronary artery bypass grafting surgery

Rev Bras Cir Cardiovasc 2012;27(2):231-9

one year in the following domains: pain, functional capacity, and physical and mental health [28]. In the preoperative period, the SF-36 questionnaire showed the highest score in the group with a walking course of more than 350 meters in the following domains: physical capacity (P <0.01), role-physical (P = 0.03), general health (P <0.01), vitality (P <0.01), and social functioning (P <0.01). In other words, patients with a longer walking course before the operation have better QOL in these domains in the preoperative period. Two months after the operation, the group with a walking course of more than 350 meters continued to have better QOL compared with the group with a walking course of less than 350 meters in the following domains: physical capacity (P <0.01), vitality (P <0.01), social functioning (P = 0.01), and mental health (P <0.01). Patients with a short walking course in the 6MWT presented a worse QOL in both evaluation periods in most domains of the SF36 questionnaire. The application of the SF-36 questionnaire, in spite of being adapted to the Portuguese language, presented understanding difficulties for some of the patients. However, the observer was trained to assist the patient to answer the questionnaire. The observer was instructed to interfere as little as possible. Data from this study contribute to the knowledge of QoL in patients undergoing CABG surgery and its relationship with the 6MWT. Although QoL assessments are to be carried out by a subjective questionnaire, they have provided us with important information about the patient’s perception of their health. The patients’ follow-up was performed by the same team that started physical therapy and medical treatment. The interviews on QOL were conducted by the same researcher, what contributed to improve the reliability of the results.

2. Iglézias JCR, Chi A, Talans A, Dallan LAO, Lourenção Júnior A, Stolf NAG. Desfechos clínicos pós-revascularização do miocárdio no paciente idoso. Rev Bras Cir Cardiovasc. 2010;25(2):229-33.

CONCLUSION CABG surgery improved the QOL in all patients. The improvement was greater in patients who walked less than 350 meters preoperatively. The preoperative 6MWT has correlation with QOL only two months after CABG surgery.

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17. Rostagno C. Six-minute walk test: independent prognostic marker? Heart. 2010;96(2):97-8. 18. Bittner V, Weiner DH, Yusuf S, Rogers WJ, McIntyre KM, Bangdiwala SI, et al. Prediction of mortality and morbidity with a 6-minute walk test in patients with left ventricular dysfunction. SOLVD Investigators. Jama. 1993;270(14):1702-7. 19. De Feo S, Tramarin R, Lorusso R, Faggiano P. Six-minute walking test after cardiac surgery: instructions for an appropriate use. Eur J Cardiovasc Prev Rehabil. 2009;16(2):144-9. 20. Terashima K, Yoshimura Y, Hirai K, Kusaka Y. QOL-associated factors in elderly patients who underwent cardiovascular surgery. Environ Health Prev Med. 2012;17(2):131-8. 21. Rasekaba T, Lee AL, Naughton MT, Williams TJ, Holland AE. The six-minute walk test: a useful metric for the cardiopulmonary patient. Intern Med J. 2009;39(8):495501. 22. Cote CG, Casanova C, Marin JM, Lopez MV, Pinto-Plata V, de Oca MM, et al. Validation and comparison of reference

24. Lindquist R, Dupuis G, Terrin ML, Hoogwerf B, Czajkowski S, Herd JA; POST CABG Biobehavioral Study Investigators, et al. Comparison of health-related quality-of-life outcomes of men and women after coronary artery bypass surgery through 1 year: findings from the POST CABG Biobehavioral Study. Am Heart J. 2003;146(6):1038-44. 25. Kapetanakis EI, Stamou SC, Petro KR, Hill PC, Boyce SW, Bafi AS, et al. Comparison of the quality of life after conventional versus off-pump coronary artery bypass surgery. J Card Surg. 2008;23(2):120-5. 26. Gjeilo KH, Wahba A, Klepstad P, Lydersen S, Stenseth R. Recovery patterns and health-related quality of life in older patients undergoing cardiac surgery: a prospective study. Eur J Cardiovasc Nurs. 2011. 27. Nogueira CRSR, Hueb W, Takiuti ME, Girardi PBMA, Nakano T, Fernandes F, et al. Qualidade de vida após revascularização cirúrgica do miocárdio com e sem circulação extracorpórea. Arq Bras Cardiol. 2008;91(4):238-44. 28. Falcoz PE, Chocron S, Stoica L, Kaili D, Puyraveau M, Mercier M, et al. Open heart surgery: one-year self-assessment of quality of life and functional outcome. Ann Thorac Surg. 2003;76(5):1598-604.

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ORIGINAL ARTICLE

Rev Bras Cir Cardiovasc 2012;27(2):240-50

Predicted preoperative maximal static respiratory pressures in adult cardiac surgeries: evaluation of two formulas Pressões respiratórias máximas no pré-operatório de cirurgias cardíacas em adultos: avaliação de duas fórmulas

Ricardo Kenji Nawa1, Ada Clarice Gastaldi2, Elisângela Aparecida Soares da Silva3, Viviane dos Santos Augusto4, Alfredo José Rodrigues5, Paulo Roberto Barbosa Evora6

DOI: 10.5935/1678-9741.20120040

RBCCV 44205-1377

Abstract Objectives: Cardiac surgery (CC) determines systemic and pulmonary changes that require special care. What motivated several studies conducted in healthy subjects to assess muscle strength were the awareness of the importance of respiratory muscle dysfunction in the development of respiratory failure. These studies used maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) values. This study examined the concordance between the values predicted by the equations proposed by Black & Hyatt and Neder, and the measured values in cardiac surgery (CS) patients. Methods: Data were collected from preoperative evaluation forms. The Lin coefficient and Bland-Altman plots were used for statistical concordance analysis. The multiple linear regression and analysis of variance (ANOVA) were used to produce new formulas. Results: There were weak correlations of 0.22 and 0.19

in the MIP analysis and of 0.10 and 0.32 in the MEP analysis, for the formulas of Black & Hyatt and Neder, respectively. The ANOVA for both MIP and MEP were significant (P <0.0001), and the following formulas were developed: MIP = 88.82 - (0.51 x age) + (19.86 x gender), and MEP = 91.36 (0.30 x age) + (29.92 x gender). Conclusions: The Black and Hyatt and Neder formulas predict highly discrepant values of MIP and MEP and should not be used to identify muscle weakness in CS patients.

1. Master Degree; Ribeirão Preto Faculty of Medicine, University of São Paulo, Department of Surgery and Anatomy, Ribeirão Preto, SP, Brazil. 2. PhD; Ribeirão Preto Faculty of Medicine, University of São Paulo, Department of Biomechanics, Medicine and Rehabilitation, Ribeirão Preto, SP, Brazil. 3. Quantitative Methods Center; Ribeirão Preto Faculty of Medicine, Hospital das Clínicas, Ribeirão Preto, SP, Brazil. 4. Master Degree; Ribeirão Preto Faculty of Medicine, University of São Paulo, Department of Surgery and Anatomy, Ribeirão Preto, SP, Brazil. 5. MD, PhD; Ribeirão Preto Faculty of Medicine, University of São Paulo, Department of Surgery and Anatomy, Ribeirão Preto, SP, Brazil. 6. Full Professor; Ribeirão Preto Faculty of Medicine, University of São Paulo, Department of Surgery and Anatomy, Ribeirão Preto, SP, Brazil.

Work performed at Ribeirão Preto Faculty of Medicine, University of São Paulo. Hospital das Clínicas, University of São Paulo, Ribeirão Preto, SP, Brazil.

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Descriptors: Thoracic surgery. Perioperative care. Respiratory insufficiency. Respiratory muscles. Resumo Objetivos: A cirurgia cardíaca (CC) determina alterações que demandam cuidados específicos no pós-operatório, incluindo as alterações pulmonares. A consciência da

Correspondence address Paulo Roberto Barbosa Evora Departament of Surgery and Anatomy – 9th floor Ribeirão Preto, SP, Brazil – Zip code 14048-990 E-mail: prbevora@netsite.com.br This study was supported by the Foundation for Research Support of the State of São Paulo (FAPESP) and Foundation for Education, Research and Assistance Support (FAEPA), Faculty of Medicine of Ribeirão Preto Clinical Hospital, University of São Paulo (FAEPA/ HCFMRP/USP), SP, Brazil. Article received on December 22nd, 2011 Article accepted on March, 21st, 2012


Nawa RK, et al. - Predicted preoperative maximal static respiratory pressures in adult cardiac surgeries: evaluation of two formulas

Abbreviations, acronyms & symbols CABG CI CPB CS FAEPA/HCFMRP/USP

FAPESP LB MEP MIP PEMÁX PIMÁX RV TLC UA UB VT

Coronary artery bypass graft Confidence interval Cardiopulmonary bypass Cardiac surgery Foundation for Education, Research and Assistance Support (FAEPA), Faculty of Medicine of Ribeirão Preto Clinical Hospital, University of São Paulo (FAEPA/HCFMRP/USP), SP, Brazil. Foundation for Research Support of the State of São Paulo (FAPESP) Lower bound Maximal expiratory pressure Maximal inspiratory pressure Pressão expiratória máxima Pressão inspiratória máxima Residual volume Total lung capacity Upper airway Upper bound Tidal volume

importância da disfunção da musculatura respiratória na insuficiência respiratória motivou o desenvolvimento de diversos estudos da força muscular em indivíduos saudáveis. Esses trabalhos utilizam valores de pressão inspiratória máxima (PIMÁX) e pressão expiratória máxima (PEMÁX). O

INTRODUCTION Cardiac surgery (CS) induces systemic changes, including pulmonary changes that require specialized postoperative attention. In recent decades, the number of patients with cardiovascular diseases requiring surgical intervention has increased significantly. In adults, the most frequent indications for CS are heart valve diseases and coronary artery disease. Although considered safe, these surgeries are not free from complications; CS has an incidence of postoperative complications of approximately 5% [1]. Lung changes are the most frequent complication, occurring in up to 70% of cases and are responsible for atelectasis and pneumonia (24.7%) and hypoxemia and pleural effusion (47.5%) [2,3]. The respiratory muscles play a key role in the maintenance of the ventilation process. Therefore, recognizing patients with preoperative respiratory muscle weakness identifies those at increased risk of postoperative complications [4]. The effect of age on respiratory muscles cannot be

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presente estudo avaliou a concordância existente entre os valores preditos pelas equações propostas por Black & Hyatt e Neder et al., com valores observados em pacientes submetidos à CC. Métodos: Os dados foram coletados das fichas de avaliação pré-operatória. Para a análise estatística verificou-se a concordância existente entre os valores preditos e observados pelas as equações de Black & Hyatt e Neder et al., sendo utilizado o coeficiente de concordância de Lin e o gráfico de Bland-Altman. Posteriormente, os dados foram submetidos à regressão linear múltipla e análise de variância, para proposição de novas fórmulas. Resultados: Para PIMÁX, observou-se fraca concordância de 0,22 e 0,19 e para PEMÁX, 0,10 e 0,32, respectivamente, para as fórmulas de Black & Hyatt e Neder et al. Os valores da ANOVA para PIMÁX e PEMÁX, foram significativas (P<0,0001), permitindo propor as seguintes fórmulas: PIMÁX = 88,82 - (0,51 x Idade) + (19,86 x Sexo), e para PEMÁX = 91,36 - (0,30 x Idade) + (29,92 x Sexo). Conclusão: As fórmulas de Black e Hyatt e Neder et al. predizem valores de PIMÁX e PEMÁX discrepantes, não devendo ser utilizadas para identificar fraqueza muscular em pacientes submetidos a cirurgia cardíaca.

Descritores: Cirurgia torácica. Assistência perioperatória. Cuidados pré-operatórios, métodos. Insuficiência respiratória. Músculos respiratórios.

ignored; muscle strength of the peripheral muscles, as well as the respiratory muscles, reduces with advancing age. In preparing patients for surgery, the detection of decreased respiratory muscle strength during the physiotherapy assessment prior to CS leads to early intervention and optimization of a program to strengthen the respiratory muscles. Like the integrated index (index of rapid shallow breathing index and CROOP), rates of respiratory muscle pump function, represented by the measurement of maximal inspiratory pressure (MIP), are widely used in clinical practice. The instruments can predict weaning success in patients undergoing mechanical ventilation, and assessing the performance of respiratory muscles is a crucial decision point for initiating weaning. Awareness of the importance of respiratory muscle dysfunction in the contribution of respiratory failure led to the development of several studies conducted in healthy subjects in order to assess indirectly muscle strength by evaluating maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) values. There are several 241


Nawa RK, et al. - Predicted preoperative maximal static respiratory pressures in adult cardiac surgeries: evaluation of two formulas

Rev Bras Cir Cardiovasc 2012;27(2):240-50

equations available in the literature to assess MIP and MEP, but two are widely used; the formulas proposed by Black & Hyatt [5] and Neder et al. [6] were established using pressure values measured in normal populations. Thus, this study examined the agreement between the maximal static respiratory pressures predicted by these two equations and the actual measured values among patients undergoing elective CS.

age 53.69 ± 15.51 years for females and 62.75 ± 7.33 years for males) and 48 (47.76%) valve replacement patients (mean age 59.5 ± 7.32 years for females and 55.09 ± 16.35 years for males). The formulas obtained in the first stage of the study were submitted to the validation process to determine the applicability of these equations in a new group.

METHODS Data Collection This study was a retrospective design, divided into two stages that used data from 438 evaluation forms collected by the Department of Physical Therapy, Cardiopulmonary Division of Thoracic and Cardiovascular Surgery (Hospital das Clinicas; Faculty of Medicine of Ribeirão Preto - FMRP / USP) between January 2004 and December 2010. The evaluation forms contained patient assessment data from the preoperative phase and are archived in the Postoperative Unit of Thoracic and Cardiovascular Surgery. The study used data contained in the form that did not deal directly with patients or cause any potential damage or identification. For this reason, the justification for waiving the requirement of consent was approved by the Research and Ethics Committee of the Ribeirão Preto Clinical Hospital - FMRP / USP. Patient Population The study included adults of both genders aged 18 to 85 years undergoing elective coronary artery bypass grafting or heart valve replacement (mitral or aortic). Criteria exclusion included individuals with incomplete data, those with evaluation forms containing observations regarding the patient’s difficulty in understanding the maximum effort inspiratory and/or expiratory maneuvers; patients diagnosed with an aortic aneurysm, unstable angina, or a left main coronary artery lesion. First Stage - Analysis of Concordance The first stage of the study evaluated data from 337 forms collected from January 2004 to December 2009, including 172 (51.03%) coronary artery bypass graft (CABG) patients (mean age 60.27 ± 9.80 years) and 165 (48.97%) valve replacement patients (mean age 49.72 ± 15.42 years). Of these patients, 187 (55.49%) were male and 150 (44.51%) were female. Second Stage - Validation The second stage of the study evaluated 101 forms collected from January 2010 to December 2010 and was aimed at validating the proposed formulas. The 101 evaluation forms included 53 (52.24%) CABG patients (mean 242

Measurements of Maximal Respiratory Pressures The physical therapy team was previously trained to perform maximal static respiratory pressure measurements in a standardized method according to the guidelines for pulmonary function testing. We used an analog manometer model MV-150/300 (Ger-Ar Trade Equipamentos Ltda. São Paulo, SP, Brazil) cmH2O and graduated with a variation of ± 300 cmH2O. This manometer was fitted with an oral adapter containing a hole approximately 2 mm in diameter to avoid an increase in intraoral pressure induced by the contraction of the buccinator muscles. The method used in this study is in accordance with the recommendations of two other studies [7,8]. For the measurements, each patient was seated in a chair, so that the trunk remained at 90 degrees to the hips, and the feet were placed flat on the floor. A nose clip was used to block the upper airway (UA) during the performance of all maneuvers. First, each patient performed the maneuvers twice in order to demonstrate the proper method for the measurements; these measurements were discarded. Next, at least three reproducible maneuvers were performed, with a one-minute interval between them; measurements with a variation of more than 10% were discarded. The highest values of MIP and MEP were adopted as reference values for each patient. Measurement of Maximal Inspiratory Pressure (MIP) With the patient properly positioned, the measurement of MIP values was completed. The maximum static respiratory effort was assessed starting from the maximum expiration of air in the lungs, a lung volume that corresponds to the residual volume (RV). For this maneuver, a mouthpiece was connected and patients performed the maximal inspiratory effort against an occluded airway (Mueller maneuver). Acceptable maneuvers were considered those that maintained the value for at least one second [5,6,9-14]. Measurement of Maximal Expiratory Pressure (MEP) To measure the MEP values, the patients were properly positioned, as previously described. They were instructed to inhale as much as possible until they reached the total lung capacity (TLC), and then were guided to maximum expiration through the mouthpiece, also against an occluded airway (Valsalva maneuver). As with MIP, the values were


Nawa RK, et al. - Predicted preoperative maximal static respiratory pressures in adult cardiac surgeries: evaluation of two formulas

considered acceptable when they were maintained for at least one second. Reference Values The reference pressure values of predicted maximal static inspiratory and expiratory values were calculated from equations suggested by Black & Hyatt [5] and Neder et al. [6] as shown in Table 1. Statistical Analysis Statistical analysis was performed separately for each stage of the study: concordance analysis, multiple linear regression and validation. For protocol analysis, the concordance coefficients of Lin [15] and Bland & Altman plots [16] were used, and the ANOVA test was used for multiple linear regression. The coefficient proposed by Lin [15] varies between 0 and 1 and measures the degree of similarity between two instruments, using variables in continuous scale. For the Bland & Altman analysis, the ordinate axis represents the difference in measurement’s values and the x-axis represents the sum over 2. The same tests were applied to the validation stage. The results were obtained with the help of SAS ® 9.0 software. Results were considered significant with a P-value < 0.05. Table 1. Equations proposed by Black and Hyatt (1969) and Neder et al. (1999) to calculate predicted values of maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) according to age. M IP

Male Female M EP Male Female

Black 143 – 104 – 268 – 170 –

& Hyatt [5] Neder et al. [6] (0.55 x age) -0.80(age) + 155.3 EPE=17.3 (0.51 x age) -0.49(age) + 110.4 EPE=9.1 (1.03 x age) -0.81(age) + 165.3 EPE=15.6 (0.53 x age) -0.61(age) + 115.6 EPE=11.2

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RESULTS First Stage - Analysis of Concordance of Maximal Static Respiratory Pressures Maximal Inspiratory Pressure (MIP) Figure 1 is a graphic plot of all MIP values, without any distinction of gender or age, calculated by the equations of Black & Hyatt and represented by a Bland & Altman plot and Lin’s coefficient. The value of Lin’s concordance coefficient (0.22) showed poor agreement when the predicted and collected values were compared. Similarly, Figure 2 is a graphic plot of all MIP values, without any distinction of age or gender, calculated by the equations of Neder et al. and represented by a Bland-Altman plot and Lin’s coefficient. The value of Lin’s concordance coefficient (0.19) is also considered a weak agreement between predicted and collected values. According to the analysis of variance (ANOVA), each relevant covariate collected this study (age, gender, weight and height) was statistically significant (P-value <0.0001) in estimating MIP. According to multiple linear regression analysis of the individual estimates of each variable (age, gender, weight and height), weight and height do not significantly affect MIP (P-level >0.05). These variables are shown in Table 2. The linear regression model and estimated values for MIP (ANOVA) involving only the covariates with a significance level of P<0.05 (age and gender) showed statistical significance (P-value <0.0001). The estimated values for MIP were shown in Table 3. This statistical analysis allowed the creation of a new formula for calculating the MIP for patients who underwent elective CS (Figure 3).

Fig. 1 - Bland-Altman plot and Lin's coefficient of maximal inspiratory pressure (MIP) values predicted by the formula of Black and Hyatt. Confidence interval 95% (0.16 – 0.29); Lin coefficient (0.22)

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Fig. 2 - Bland-Altman plot and Lin's concordance coefficient of maximal inspiratory pressure (MIP) values predicted by the formula of Neder et al. Confidence interval 95% (0.14 – 0.25); Lin coefficient (0.19)

Table 2. Multiple linear regression model to estimate individual MIP considering all the variables. (CI=confidence interval; LB=lower bound; UB=upper bound) Variable Intercept Age Gender Weight Height

Estimation 106.38 -0.54 20,85 0.17 -16.94

CI (95%) LB UB 183.79 28.96 -0.31 -0.78 29.51 12.18 0.40 -0.06 -67.60 33.71

P–value 0.007 <0.0001 <0.0001 0.15 0.51

Fig. 3 - Proposed maximal inspiratory pressure (MIP) formula, according to multiple linear regression model

Maximal Expiratory Pressure (MEP) Figure 4 is a graphic plot of MEP values, without any distinction of gender or age, predicted by the equations of Black & Hyatt and represented by a Bland-Altman plot and Lin’s coefficient. The value of Lin’s concordance coefficient (0.10) showed poor agreement between the predicted and collected values. Figure 5 is a graphic plot of MEP values, without any distinction of gender or age, predicted by the equations of Neder et al. and represented by a Bland-Altman plot and 244

Table 3. Estimated MIP linear regression model containing only the covariates of age and gender. (CI=confidence interval; LB=lower bound; UB=upper bound) Variable Intercept Age Gender*

Estimation 88.82 -0.51 19.86

CI (95%) LB UB 76.30 101.34 -0.73 -0.29 13.74 25.98

P – value <0.0001 <0.0001 <0.0001

Lin’s coefficient. The value of Lin’s concordance coefficient (0.32) showed poor agreement between the predicted and collected values. According to the ANOVA, each relevant covariates collected in this study (age, gender, weight and height) was statistically significant (P-value <0.0001) in predicting MEP. According to multiple linear regression analysis of the individual estimates of each variable (age, gender, weight and height), weight and height do not significantly affect MEP (P-value <0.05). These variables are shown in Table 4. The linear regression model and estimated values for MEP (ANOVA) involving only the covariates with a significance level of P<0.05 (age and gender) showed statistical significance (P-value <0.0001). The estimated values for MEP were shown in Table 5. This statistical analysis allowed the creation of a new formula for calculating the MEP for patients who underwent elective CS (Figure 6).


Nawa RK, et al. - Predicted preoperative maximal static respiratory pressures in adult cardiac surgeries: evaluation of two formulas

Rev Bras Cir Cardiovasc 2012;27(2):240-50

Fig. 4 - Bland-Altman plot and Lin's concordance coefficient of maximal expiratory pressure (MEP) values predicted by the formula of Black and Hyatt. Confidence interval 95% (0.08 – 0.13); Lin coefficient (0.10)

Fig. 5 - Bland-Altman plot and Lin's concordance coefficient of maximal expiratory pressure (MEP) values predicted by the formula of Neder et al. Confidence interval 95% (0.24 – 0.39); Lin coefficient (0.32)

Table 4. Estimated MEP linear regression model containing all covariates. (CI=confidence interval; LB=lower bound; UB=upper bound) Variable Intercept Age Gender Weight Height

Estimation 98.24 -0,34 29.70 0.26 -13.99

CI (95%) LB UB 6.85 189.63 -0.61 -0.06 19.47 39.93 -0.01 0.53 -73.78 45.81

P – value 0.04 0.02 <0.0001 0.06 0.65

Table 5. Linear regression model of MEP containing only the covariates of age and gender (CI=confidence interval; LB=lower bound; UB=upper bound) Variable Intercept Age Gender*

Estimation 91.36 -0.30 29.92

CI (95%) UB LB 106.18 76.53 -0.04 -0.56 37.17 22.67

P– value <0.0001 0.0221 <0.0001

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Nawa RK, et al. - Predicted preoperative maximal static respiratory pressures in adult cardiac surgeries: evaluation of two formulas

Fig. 6 - Proposed maximal expiratory pressure (MEP) formula, according to multiple linear regression model

Second Stage - Validation Maximum Inspiratory Pressure (MIP) Figure 7 is a graphic plot of the MIP values predicted by the new formula after the ANOVA with regard to gender. Lin’s concordance coefficient (0.32) demonstrated a weak correlation between the values predicted by the proposed new formula and the collected values. However, the average percentage error for calculating MIP using the new formula was 15.7% between the predicted and collected values. Maximal Expiratory Pressure (MEP) Figure 8 is a graphic plot of the MEP values predicted using the new formula after the ANOVA with regard to gender. Lin’s concordance coefficient (0.36) demonstrated a weak correlation between the values predicted by the proposed new formula and the collected values. However, the average percentage error for calculating MEP using the new formula was 0.4% between the predicted and collected values. DISCUSSION The existing formulas for the evaluation of respiratory muscle strength are based on spirometry data performed in

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normal populations. Thus, there are controversies whether they can be applied indiscriminately in patients with respiratory disorders and/or subjected to thoracic or cardiovascular surgery, in which the surgical incisions themselves may alter the dynamics of the rib cage muscles. To test this hypothesis in patients undergoing CS, we adopted the use of two formulas: (1) the classic formula of Black and Hyatt and (2) Neder’s formula, which is established as the standard for the Brazilian population. Ultimately, this research consisted of a statistical exercise in order to evaluate the suitability of two formulas to determine the respiratory muscle strength in patients scheduled for heart surgery. All patients undergoing elective CS undergo preoperative examinations, including analysis by a physiotherapist. Thus, it is possible to identify in advance those patients with compromised respiratory muscles. And, after obtaining MIP and MEP values in the preoperative period, it is possible to engage in exercises designed to gain respiratory muscle strength. Specifically, changes in lung function in patients undergoing cardiopulmonary bypass (CPB) are primarily responsible for increasing postoperative mortality [17]. To improve outcomes concerning changes in lung function after extensive surgical procedures, it is not uncommon to control postoperative complications arising from heart surgery such as pain, arrhythmias, reduced lung volumes and capacities, and, especially, areas of atelectasis [18]. Several studies regarding maximal static respiratory pressures have been published since the pioneering study of Black 7 Hyatt [5] proposed the first formulas to calculate

Fig. 7 - Bland-Altman plot and Lin's concordance coefficient of maximal inspiratory pressure (MIP) values predicted by the proposed new formula. Confidence interval 95% (0.21 – 0.42); Lin coefficient (0.36); o=female and =male

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Fig. 8 - Bland-Altman plot and Lin's concordance coefficient of maximal expiratory pressure (MEP) values predicted by the proposed new formula. Confidence interval 95% (0.24 – 0.47); Lin coefficient (0.32); o=female and =male

the MIP and MEP according to age. Measurements performed in an easy and noninvasive method show a significant correlation between the inspiratory and expiratory peaks and the strength of a patient’s respiratory muscles. Differences are often found between the predicted and observed values for various ethnic groups. Such differences involve anthropometric characteristics and cultural factors and led to the proposal of new formulas in order to adjust the values of MIP and MEP for the populations in question. An extensive systematic review by Evans and Whitelaw [19] examined different formulas in the literature, in order to investigate and discuss benchmarks for the lower limit of normal, as well as the mouthpiece used in data collection. It must be emphasized that the maximal static respiratory pressures (MIP and MEP) are indirect indicators of the inspiratory and expiratory muscle strength and are essential to promote tidal volume (VT) during the ventilation process. Significant reductions in muscle strength can lead to inadequate ventilation and “clearance” of the airways [20]. For the exploratory analysis of data in the first stage of our study, we created graphical representations (“Plots”) of MIP values without any distinction of gender or age. According to the values predicted by the equations of Black and Hyatt [5] and Neder et al. [6], the graphic analysis of the Plot for the formula of Black and Hyatt, and the value of Lin’s concordance coefficient (0.22), there was a weak correlation between the predicted and collected values of MIP. The same occurred when graphically analyzing the Plot for the formula of Neder et al. and Lin’s correlation coefficient (0.19), indicating a weak agreement (Figures 1

and 2). These reliability values observed for the MIP can be attributed to the fact that both formulas underestimated and overestimated some of the predicted values. Studies of Black & Hyatt [5] and Neder et al. [6] evaluated only healthy individuals to establish their formulas. However, the population in this study had comorbidities that could lead to changes in the respiratory system and/or muscles and influence the values of MIP and MEP. It was evident after the first stage that the formulas of Black and Hyatt [5] and Neder et al. [6] have low sensitivity to predict values of MIP and MEP for this population of patients undergoing CS. Thus, the data were then subjected to ANOVA for MIP involving all relevant covariates collected in this study (age, gender, weight and height); each showed statistical significance level <0.0001 (Table 2). Although MIP submitted to ANOVA had a significance level of P<0.05, it was necessary to verify that all the covariates contributed significantly to the proposed model. Thus, we analyzed the independent variables and observed that weight and height did not have a significance level <0.05, and are not, in this case, relevant variables to be considered for inclusion in the multiple linear regression model. An additional analysis was performed for MIP that involved only the covariates with a significance level <0.05 (age and gender), and the resulting model showed continued significance level <0.0001 (Table 3). In this sequence analysis, when covariates were observed individually, each had a significance level <0.0001, indicating that all the variables contributed positively to the multiple linear regression model. Evaluating the results of the ANOVA with the significance levels allowed the creation of a new formula 247


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for calculating MIP for patients undergoing elective CS: MIP = 88.82 - (0.51 x age) + (19.86 x gender [value 1 for males and 0 for females]). Similar to the exploratory data analysis of MIP, we obtained the plot of the values of MEP without distinction of gender or age, according to the values predicted by the equations of Black & Hyatt and Neder et al. [6] (Figure 3). By analyzing the Plot graphic analysis for the MEP values from the formula of Black & Hyatt [5] and by evaluating Lin’s coefficient (0.10), we observed a weak correlation between the predicted and measured MEP values (Figure 4). The same occurred when graphically analyzing the Plot for the formula of Neder et al. [6] and Lin’s coefficient (0.32), indicating weak agreement between predicted and collected values. As for the MIP, the poor similarity observed in the MEP values can also be attributed to the fact that there are underestimated and overestimated values predicted by both formulas. The ANOVA performed with data collected from MEP considered all relevant covariates (age, gender, weight and height) and identified a significance <0.0001 (Table 4). However, again, it was necessary to verify that all variables involved contributed significantly to the model, with the significance level <0.05. The analysis of individual covariates showed that height and weight did not have a significance level <0.05. In this case, the variables of weight and height were not considered relevant to the application of multiple linear regression and excluded from further analysis. Thus, a new ANOVA was performed for MEP that involved only the covariates with a significance level of P<0.05 (age and gender). The resulting model continued to show a significance level <0.0001 (Table 5). This time, however, when viewed individually, each variable showed a level of significance <0.05, demonstrating that all variables contributed significantly to the multiple linear regression model. Based on the ANOVA results, we created a new formula for calculating MEP for patients undergoing CS: MEP = 91.36 - (0.30 x age) + (29.92 x gender [value 1 for males and 0 for females]). The second phase of research was the process of validating the proposed formulas and applying them to data obtained in 101 additional evaluation forms. In this stage, 53 (52.24%) of the patients had a surgical indication for CABG. For exploratory data analysis to validate the formulas, a plot was again constructed from the MIP values predicted by the new formula after the ANOVA, but, this time, with respect to gender (Figure 5). According to plot graphic analysis of the MIP values and Lin’s concordance coefficient (0.32), we observed a weak correlation between the MIP values predicted by the proposed new formula and the collected values. However, the average percentage

error for MIP of the new formula was 15.7 % between the predicted and collected values. As performed for MIP, a plot was obtained with the MEP values predicted by the new formula after the ANOVA, with respect to gender (Figure 6). Similar to the MIP findings, the plot for graphical analysis of the MEP values and Lin’s concordance coefficient (0.36) demonstrated a weak correlation between the values predicted by the proposed new formula and the collected values. However, the average percentage error for MEP of the new formula was 0.4% between the predicted and collected values. Although the results demonstrated a poor agreement between the values predicted by the new formula and the observed population data, the percentage error is acceptable for measurements of MIP and increased for MEP. The results also showed higher values of MIP and MEP for men compared to women, which is in agreement with previous studies that found MIP for men was 34-66% greater than MIP for women and MEP was 41-57% greater for men than women, depending on age [21,22]. Age is highly correlated with the ability to generate force by skeletal muscles because, over the years, muscle strength tends to decline due to natural aging processes. Among studies of elderly patients, the values predicted by the formulas vary widely, mainly due to the small number of patients over the age of 75 years [23]. One study observed no correlation between MIP and age in the elderly [24], while at least two different studies found a strong correlation between the values of maximum static respiratory pressure and age. A large study by Carpenter et al. [25] involving 13,005 individuals aged 47 to 68 years observed a decline in MIP with older age. Yearly declines of 1.1 cmH2O for men and 0.9 cmH2O for women were observed, reaching values remarkably similar to those observed by Enright et al. [24]. When assessing respiratory muscle strength, measures of MIP and MEP may be indicators of weakness. However, the maximal static respiratory pressures only measure the combined effect of the activity of several muscles that directly or indirectly contribute to power generation for the maximum static respiratory effort. Therefore, these figures should be interpreted with caution, as some patients who have an underlying disease may have MIP and MEP values near the normal range, but still develop abnormally rapid fatigue with exercise. Likewise, some patients with MIP and MEP values below the lower limits of normal can breathe perfectly well without any difficulties. The classification of respiratory muscle weakness should not be solely based on the individual values of MIP and MEP. Furthermore, an important to note is that all previously published studies were based on healthy patients without any previous illnesses or comorbidities. The patients in this study could present insufficient pulmonary respiratory

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mechanics, reduced lung volumes and chest expansion, and/or possible altered diaphragmatic excursion, as observed in previous studies [22,23].

off-pump coronary artery bypass graft surgery: an observational follow-up study. BMC Pulm Med. 2009;9:36.

Study limitation Owing to the fact that it was a retrospective analysis, with data collected during from January 2004 to December 2010, it was impossible for a single professional to collect data from the evaluation forms at the time of the patient hospitalization. Clinical problems as renal failure, hypertension, tabagism and obstructive lung disease, which are frequent were not considered for exclusion criteria because they have relatively high incidence in adult patients after cardiac surgery. However, this option would be considered for criticism. CONCLUSIONS This study reaches two main conclusions: 1) Neither Black and Hyatt’s nor Neder et al.’s formula reached complete agreement between predicted and observed maximal static respiratory pressure values in patients undergoing CS, and 2) the proposed new formulas have a low percentage error (15.7% for MIP and 0.4% for MEP) and are, therefore, more appropriate when used for a population of patients undergoing CS. Support Statement This study was supported by the Foundation for Research Support of the State of São Paulo (FAPESP) and Foundation for Education, Research and Assistance Support (FAEPA), Faculty of Medicine of Ribeirão Preto Clinical Hospital, University of São Paulo (FAEPA/HCFMRP/USP), SP, Brazil. Statement of Interest None declared. ACKNOWLEDGEMENTS The authors would like to thank the patients, physicians and physiotherapists from the Division of Thoracic and Cardiovascular Surgery.

REFERENCES

3. Herdy AH, Marcchi PL, Vila A, Tavares C, Collaço J, Niebauer J, et al. Pre- and postoperative cardiopulmonary rehabilitation in hospitalized patients undergoing coronary artery bypass surgery: a randomized controlled trial. Am J Phys Med Rehabil. 2008;87(9):714-9. 4. Garcia RCP, Costa D. Treinamento muscular respiratório em pós-operatório de cirurgia cardíaca eletiva. Rev Bras Fisioter. 2002;6(3):139-46. 5. Black LF, Hyatt RE. Maximal respiratory pressures: normal values and relationship to age and sex. Am Rev Respir Dis. 1969;99(5):696-702. 6. Neder JA, Andreoni S, Lerario MC, Nery LE. Reference values for lung function tests. II. Maximal respiratory pressures and voluntary ventilation. Braz J Med Biol Res. 1999;32(6):719-27. 7. Camelo Jr JS, Terra JT, Manço JC. Pressões respiratórias máximas em adultos normais. J Pneumol. 1985;11(4):181-4. 8. Sobush DC, Dunning M 3rd. Assessing maximal static ventilatory muscle pressures using the "bugle" dynamometer. Suggestion from the field. Phys Ther. 1984;64(11):1689-90. 9. Vincken W, Ghezzo H, Cosio MG. Maximal static respiratory pressures in adults: normal values and their relationship to determinants of respiratory function. Bull Eur Physiopathol Respir. 1987;23(5):435-9. 10. Bruschi C, Cerveri I, Zoia MC, Fanfulla F, Fiorentini M, Casali L, et al. Reference values of maximal respiratory mouth pressures: a population-based study. Am Rev Respir Dis. 1992;146(3):790-3. 11. Fiz JA, Carreras A, Aguilar J, Gallego M, Morera J. Effect of order on the performance of maximal inspiratory and expiratory pressures. Respiration. 1992;59(5):288-90. 12. Wilson SH, Cooke NT, Edwards RH, Spiro SG. Predicted normal values for maximal respiratory pressures in Caucasian adults and children. Thorax. 1984;39(7):535-8. 13. Wagener JS, Hibbert ME, Landau LI. Maximal respiratory pressures in children. Am Rev Respir Dis. 1984;129(5):873-5. 14. McElvaney G, Blackie S, Morrison NJ, Wilcox PG, Fairbarn MS, Pardy RL. Maximal static respiratory pressures in the normal elderly. Am Rev Respir Dis. 1989;139(1):277-81.

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2. Yánez-Brage I, Pita-Fernández S, Juffé-Stein A, MartínezGonzález U, Pértega-Díaz S, Mauleón-García A. Respiratory physiotherapy and incidence of pulmonary complications in

16. Bland JM, Altman DG. Comparing methods of measurement: why plotting difference against standard method is misleading. Lancet. 1995;346(8982):1085-7.

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17. Johnson D, Hurst T, Thomson D, Mycyk T, Burbridge B, To T, et al. Respiratory function after cardiac surgery. J Cardiothorac Vasc Anesth. 1996;10(5):571-7.

22. Harik-Khan RI, Wise RA, Fozard JL. Determinants of maximal inspiratory pressure. The Baltimore Longitudinal Study of Aging. Am J Respir Crit Care Med. 1998;158(5 Pt 1):1459-64.

18. Hayes JP, Williams EA, Goldstraw P, Evans TW. Lung injury in patients following thoracotomy. Thorax. 1995;50(9):990-1.

23. Watsford ML, Murphy AJ, Pine MJ, Coutts AJ. The effect of habitual exercise on respiratory- muscle function in older adults. J Aging Phys Act. 2005;13(1):34-44.

19. Evans JA, Whitelaw WA. The assessment of maximal respiratory mouth pressures in adults. Respir Care. 2009;54(10):1348-59. 20. Berry JK, Vitalo CA, Larson JL, Patel M, Kim MJ. Respiratory muscle strength in older adults. Nurs Res. 1996;45(3):154-9. 21. Hautmann H, Hefele S, Schotten K, Huber RM. Maximal inspiratory mouth pressures (PIMAX) in healthy subjects: what is the lower limit of no rmal? Respir Med. 2000;94(7):689-93.

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ORIGINAL ARTICLE

Rev Bras Cir Cardiovasc 2012;27(2):251-9

Use of intra-aortic balloon pump in cardiac surgery: analysis of 80 consecutive cases Uso do balão intra-aórtico no trans e pós-operatório de cirurgia cardíaca: análise de 80 casos consecutivos

Fernando Pivatto Júnior1, Ana Paula Tagliari1, Anderlise Bard Luvizetto2, Edemar Manuel Costa Pereira3, Erci Maria Onzi Siliprandi4, Ivo Abrahão Nesralla5, Rodrigo Pires dos Santos6, Renato Abdala Karam Kalil7

DOI: 10.5935/1678-9741.20120041

RBCCV 44205-1378

Abstract Background: The low cardiac output syndrome in perioperative period of cardiac surgery may occur in about 10 to 15% of patients; of this total, 2% require mechanical support for adequate hemodynamic control. Objective: This study aimed to describe the mortality of patients requiring intra-aortic balloon pump (IABP) in transor post-cardiac surgery, identifying preoperative variables associated with a worse outcome, as well as describe the postoperative complications and survival in the medium term. Patients and Methods: retrospective cohort study including 80 consecutive cases between January/2009 and September/ 2011. The patients had on average 62.9 ± 11.3 years and 58.8% were male. In the sample, 81.3% were hypertensive, 50% had previous myocardial infarction and 38.8% heart failure NYHA III/IV. The most common surgery performed was isolated coronary artery bypass grafting (37.5%). Results: Hospital mortality was 53.8% (95% HF: 42.764.9) and the cross-clamp time >90 minutes was an independent predictor of mortality in multivariate analysis (RR 1.52 95% HF: 1.04-2.22). Regarding complications, 71.3% (95% HF: 61.2 to 81.4) of patients had at least one additional complication: the lower limb ischemia was

observed in 5.0% of patients. The 1-year survival was 43.6%, observing a plateau in the survival rate after an initial sharp drop, related to hospital mortality. Conclusion: Patients who need the IABP form a group of very high risk for morbidity and mortality. Its use, however, allows many patients to recover an evolution that was invariably fatal, having the patients discharged home a good survival in the medium term.

1. Graduation in Medicine - Institute of Cardiology of Rio Grande do Sul / University Foundation of Cardiology (IC / FUC), Porto Alegre, Brazil. 2. Technical nursing of IC / FUC, Porto Alegre, Brazil. 3. Specialist in Cardiology and Intensive Care - IC / FUC and the Federal University of Health Sciences of Porto Alegre (UFCSPA), Porto Alegre, Brazil. 4. Degree in Nursing - IC / FUC, Porto Alegre, Brazil. 5. PhD - IC / FUC, Porto Alegre, Brazil. 6. Postdoctoral - IC / FUC, Porto Alegre, Brazil. 7. PhD - IC / FUC and the Federal University of Health Sciences of Porto Alegre (UFCSPA), Porto Alegre, Brazil.

Study conducted at the Institute of Cardiology of Rio Grande do Sul / University Foundation of Cardiology (IC / FUC), Porto Alegre, Brazil.

Descriptors: Intra-aortic balloon pumping. Cardiac surgical procedures. Cardiac output, low. Resumo Fundamento: A síndrome de baixo débito cardíaco no perioperatório de cirurgia cardíaca pode incidir em cerca de 10 a 15% dos pacientes; desse total, 2% necessitam de suporte mecânico para adequado controle hemodinâmico. Objetivos: Descrever a mortalidade de pacientes que necessitaram utilizar balão intra-aórtico (BIAo) no trans ou pós-operatório de cirurgia cardíaca, identificando variáveis pré-operatórias associadas a pior desfecho, assim como descrever as complicações pós-operatórias e a sobrevida em médio prazo.

Correspondence Address: Avenida Princesa Isabel, 370 – Santana – Porto Alegre, RS, Brazil – Zip code: 90620-000 E-mail: fpivatto@gmail.com

Article received on February 15th, 2012 Article accepted on June 11th, 2012

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Abbreviations, acronyms & symbols IABP CPB CABG LVEF AMI HF IC/FUC ARF NYHA CPA LCA VAD LV

Intra-aortic balloon pump Cardiopulmonary bypass Coronary Artery Bypass Graft Surgery Left ventricle ejection fraction Acute myocardial infarction Heart failure Institute of Cardiology of Rio Grande do Sul / FUC Acute renal failure New York Heart Association Cardiopulmonary arrest Left main coronary artery Ventricular assist devices Left ventricle

Métodos: Estudo de coorte retrospectivo incluindo 80 casos consecutivos entre janeiro/2009 e setembro/2011. Os pacientes possuíam, em média, 62,9 ± 11,3 anos e 58,8% eram do sexo masculino. Na amostra, 81,3% dos pacientes eram hipertensos, 50% tinham infarto do miocárdio prévio e 38,8%, insuficiência

INTRODUCTION The results of cardiac surgical procedures continue to improve despite the increasing number of patients older and sicker. Many deaths are linked to complications related to low cardiac output during the perioperative period [1]. The low cardiac output syndrome in the perioperative period of cardiac surgery is defined as the need for inotropic support for more than 30 minutes in the intensive care unit or intra-aortic balloon pump (IABP) in the postoperative period, associated with a significant increase in morbidity and mortality [2]. This syndrome after cardiac surgery can focus on about 10 to 15% of patients; this total, 2% require mechanical support for appropriate hemodynamic control. The main reasons stand out hypovolemia, cardiac tamponade, right ventricular dysfunction, left ventricular failure consequent to poor myocardial protection and / or perioperative myocardial infarction. The hospital mortality of patients with low cardiac output syndrome is high, being the most common cause left ventricular failure secondary to acute myocardial infarction [3]. The use of mechanical support in cardiogenic shock 252

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cardíaca NYHA III/IV. A principal cirurgia realizada foi a revascularização miocárdica isolada (37,5%). Resultados: A mortalidade hospitalar nesta série foi de 53,8% (IC95%: 42,7-64,9), sendo o tempo de isquemia ≥ 90 minutos preditor independente de mortalidade em análise multivariada (RR 1,52 IC95%: 1,04-2,22). Em relação às complicações, 71,3% (IC95%: 61,2-81,4) dos pacientes apresentaram ao menos uma complicação adicional no período perioperatório, sendo a isquemia do membro inferior observada em 5% dos pacientes. A sobrevida em 1 ano foi de 43,6%, observando-se um platô na curva de sobrevida após uma queda acentuada inicial, relacionada à mortalidade hospitalar. Conclusões: Os pacientes que necessitam do BIAo compõem um grupo de muito alto risco para morbidade e mortalidade; seu emprego, entretanto, permite recuperar muitos pacientes de uma evolução que seria invariavelmente fatal, tendo os pacientes com alta hospitalar uma boa sobrevida em médio prazo. Descritores: Balão intra-aórtico. Procedimentos cirúrgicos cardíacos. Baixo débito cardíaco.

had its beginning in models of open heart surgery, where failures occurred on withdrawal of the heart-lung bypass, in the years 1950-1960. The development of the mechanism of aortic counter-pulsation has its first records in the early years of the 1950s, however, the biggest success story occurred in 1969, with publication of Kantrowitz et al. [4] and is still commonly used connected directly to surgical treatment, because its mode of implantation is also made so that limited and hampered its routine use. From the year 1980, there was significant gain in scientific knowledge, combined with important technical industrial investment, with development of the delivery system through the femoral artery puncture with sheath and dilator [5], universalizing the use of IABP in various hospital environments , associating with it a great development of control mechanisms, which today have become almost selfadjusting [6]. The IABP is currently the device most widely used circulatory support in cardiac surgery, to result in a supply / demand ratio more favorable to heart failure [7]. \ In the U.S. alone, more than 70,000 patients annually receive hemodynamic support this device. The main indication of


Pivatto Júnior F, et al. - Use of intra-aortic balloon pump in cardiac surgery: analysis of 80 consecutive cases

Rev Bras Cir Cardiovasc 2012;27(2):251-9

use in cardiac surgery is the use in the treatment of perioperative low cardiac output refractory to inotropic support usual [8]. The growing need of the use of the IABP during cardiac surgery in recent years has been reported by many centers, this is mainly due to the fact that the patient population has changed and now includes older patients with multivessel disease and a greater degree of dysfunction ventricular. On the other hand, there is a lower threshold for the use of this device, due to improved technology and relatively low complication rate [8]. This study has as main objective to describe the mortality of patients who required the use of the IABP in trans- or post-cardiac surgery at the Institute of Cardiology of Rio Grande do Sul / FUC (IC / FUC) and identify preoperative variables associated with worse outcome. Secondarily, it aims to describe the postoperative complications and survival in the medium term this patient population.

quantitative, as the mean and standard deviation. In order to statistically assess the association between two qualitative variables, we used the chi-square or Fisher exact test when indicated. To evaluate the association between mortality risk and the variables we used Poisson regression with robust adjustment for variances, a method also used in the multivariate analysis, which included all variables with P <0.05 in univariate analysis. The description of survival was performed by Kaplan-Meier method. The confidence interval of 95% was calculated when it saw fit, as shown in parentheses. The level of significance for all tests was 5%. This study was registered at the Research Unit of IC / FUC under number 4104/07 was approved by the local Research Ethics, on February 20, 2008.

METHODS A retrospective cohort study including all patients who required the use of the IABP in trans or post-cardiac surgery in the IC / FUC, from January/2009 to September/2011, due to difficulty in removing the cardiopulmonary bypass or cardiogenic shock refractory to vasoactive drugs. The classification of heart failure (HF) was performed according to criteria established by the New York Heart Association (NYHA). Lesions of the left main coronary artery (LCA) was considered severe if greater than 50%. The presence of renal preoperative was defined in presence of serum creatinine of more than 2 mg / dl. Acute myocardial infarction (AMI) was considered recent if it occurred in the last 30 days. Current smoking was defined as smoking one cigarette in the last month. The diagnosis of lower limb ischemia was performed with a clinical basis. The mechanical ventilation time was considered prolonged if greater than 48 hours. The ischemia time was considered prolonged if greater than or equal to 90 minutes and cardiopulmonary bypass (CPB) is greater than or equal to 120 minutes. Hospital mortality was defined as the occurrence of death during hospitalization of the patient, regardless of its duration. Patients were evaluated by consulting the records and the Mortality Information System of the State Health Secretariat of Rio Grande do Sul. Patients whose follow-up was lost were censored and were included in the survival analysis up to the date of the last day of hospitalization or outpatient visit last performed. Data were collected from medical records retrospectively, being entered and analyzed with SPSS 15.0. The descriptive analysis for qualitative variables was performed from the distribution of absolute and relative frequency, and for

Table 1. Preoperative characteristics of the sample. Variable Age (±dp) Male (%) Hypertension (%) Previous AMI (%) Recent AMI (%) IC NYHA III/IV (%) LVEF 30-50% (%) LVEF < 30% (%) Previous smoking (%) Current smoking (%) Diabetes (%) Severe lesion of LCA (%) Renal dysfunction (%)

n = 80 62,9 ± 11,3 47 (58,8) 65 (81,3) 40 (50,0) 10 (12,5) 31 (38,8) 28 (35,0) 13 (16,3) 26 (32,5) 15 (18,8) 25 (31,3) 13 (16,3) 8 (10,0)

AMI: acute myocardial infarction, HF NYHA: classification of heart failure New York Heart Association, LVEF: left ventricular ejection fraction, LCA: left main coronary artery Table 2. Surgical data. Variable n = 80 Urgency of operation Elective (%) 55 (68.8) Urgency/Emergency (%) 25 (31.2) Surgeries performed CABG alone (%) 30 (37.5) Aortic valve replacement (%) 8 (10.0) Mitral valve replacement (%) 5 (6.3) CABG + Aortic valve replacement (%) 5 (6.3) Ventriculoseptoplasty (%) 4 (5.0) 4 (5.0) CABG + LV aneurysm Correction (%) CABG + Mitral valve replacement (%) 3 (3.8) 2 (2.5) Aortic + mitral valve replacement (%) Heart transplantation (%) 2 (2.5) Mitral valve replacement + tricuspid valve plasty (%) 2 (2.5) Other procedures (%) 15 (18.8) Operative times Ischemia (±sd) 81.6 ± 33.5 CPB (±sd) 127.5 ± 54.0 Ischemia > 90 min (%) 28 (35.0) 40 (50.0) CPB > 120 min (%)

CABG: coronary artery bypass grafting, LV: left ventricle, CPB: cardiopulmonary bypass

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RESULTS During the study period, 89 patients required the use of the IABP, nine (10.1%) in the preoperative period, 39 (43.8%)

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in the trans-operative, due to difficulty in weaning from CPB, and 41 (46.1%) in postoperative cardiogenic shock refractory to inotropic therapy, these last two groups, as already mentioned, objective analysis of this study.

Table 3. Univariate analysis of variables associated with mortality. Variable

n = 80

% Mortalidade

RR (IC 95%)

P

Age > 65 years

Yes No

40 40

55.0 52.5

1.05 (0.70-1.57)

1.000

Male

Yes No

47 33

59.6 45.5

1.31 (0.84-2.04)

0.308

Hypertension

Yes No

65 15

55.4 46.7

1.19 (0.67-2.13)

0.747

Diabetes

Yes No

25 55

48.0 56.4

0.85 (0.53-1.36)

0.650

Active smoking

Yes No

15 65

53.3 53.8

0.99 (0.59-1.67)

1.000

Previous smoking

Yes No

26 54

42.3 59.3

0.71 (0.43-1.18)

0.236

HF NYHA III/IV

Yes No

31 49

71.0 42.9

1.66 (1.12-2.46)

0.026

Previous AMI

Yes No

40 40

42.5 65.0

0.65 (0.43-1.00)

0.073

Recent AMI

Yes No

10 70

50.0 54.3

0.92 (0.48-1.77)

1.000

LVEF 30-50%

Yes No

28 46

57.1 52.2

1.09 (0.72-1.67)

0.861

LVEF < 30%

Yes No

13 61

46.2 55.7

0.83 (0.44-1.55)

0.747

Severe lesion of LCA

Yes No

13 61

46.2 57.4

0.80 (0.43-1.50)

0.666

Renal dysfunction

Yes No

8 72

62.5 52.8

1.18 (0.66-2.11)

0.719

Non-elective surgery

Yes No

25 55

64.0 49.1

1.30 (0.87-1.94)

0.318

CABG alone

Yes No

30 50

30.0 68.0

0.44 (0.25-0.79)

0.002

Ischemic time > 90 min

Yes No

28 52

71.4 44.2

1.61 (1.10-2.37)

0.036

CPB time > 120 min

Yes No

40 40

67.5 40.0

1.69 (1.09-2.61)

0.025

Trans Post

39 41

51.3 56.1

0.91 (0.61-1.37)

0.836

Indication

AMI: acute myocardial infarction, HF NYHA: classification of heart failure New York Heart Association, LVEF: left ventricular ejection, TEC: left main coronary artery, CABG: coronary artery bypass grafting, CPB: cardiopulmonary bypass

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The sample was therefore 80 patients, about 3.3% of the patients in the period. The mean age was 62.9 Âą 11.3 years, 40 (50%) aged greater than or equal to 65 years. The preoperative characteristics of the sample are described in Table 1. During the study period, 2.1% of all coronary artery bypass grafting (CABG) performed alone required the use of the IABP in trans or post-operative, which constitutes a major surgical procedure performed in this series of cases (37.5%.) Table 2 describes the surgeries, as well as the degree of urgency and the operative times, noting that 31.2% of the surgeries were elective and non-surgical times were prolonged ischemia and CPB in 35% and 50% of patients, respectively, and all procedures performed with CPB. The hospital mortality rate was 53.8% (95% HF: 42.7 to 64.9). In univariate analysis (Table 3), heart failure NYHA III / IV, surgery and non-CABG prolonged surgical times were associated with higher mortality a statistically significant manner. In the multivariate analysis (Table 4),

only the ischemia time> 90 min was an independent predictor of mortality, with the presence of heart failure NYHA III / IV only tend to be a predictor. Regarding complications (Table 5), 71.3% (95% HF: 61.2 to 81.4) of patients had at least one additional complication in the perioperative period. Complications directly attributable to the IABP, the lower limb ischemia were the most described, observed in four (5.0%) patients: of these, two required amputation of the lower limb, one of whom had associated rhabdomyolysis. Following one year of the 37 patients who were discharged from hospital, two had died due to complications of their underlying diseases. Of the 35 remaining patients, 32 (91.4%) completed follow-up of 6 months and 25 (71.4%) to one year, the others being censored (10 patients, 12.5% of the total sample). Survival at 6 months was 45%, and 1 year, 43.6%, observing a plateau in the survival curve after the initial sharp drop, related to hospital mortality. The survival curve of KaplanMeier method is shown in Figure 1.

Table 4. Multivariate analysis of the association of variables with mortality. Variable HF NYHA III/IV CABG alone Ischemic time > 90 min

RR* (IC 95%) 1.49 (1.00-1.23) 0.59 (0.31-1.12) 1.52 (1.04-2.22)

P* 0.050 0.108 0.029

HF NYHA: classification of heart failure New York Heart Association, CABG: coronary artery bypass graft surgery. * Adjusted for IC-NYHA III / IV, CABG, and ischemic time> 90 min: for having multicollinearity with prolonged ischemic time, it was decided not to include in this analysis CPB time> 120 min

Table 5. Perioperative complications. Complications Directly related to the IAB Lower limb ischemia (%) Lower limb amputation (%) Rhabdomyolysis (%) Aneurysm of the lower limb (%) Not directly related to the IAB Acute renal failure (%) Sepsis (%) Prolonged mechanical ventilation (%) Perioperative myocardial infarction (%) Respiratory infection (%) PCR reversed Reoperation for bleeding (%) Requiring hemodialysis (%) Wound infection in the lower limb (%) Hepatic dysfunction (%) Other complications (%)

n = 80 4 2 1 1

(5.0) (2.5) (1.3) (1.3)

28 (35.0) 21 (26.3) 19 (23.8) 16 (20.0) 11 (13.8) 11 (13.8) 9 (11.3) 6 (7.5) 4 (5.0) 2 (2.5) 4 (5.0)

IAB: IAB, AMI: acute myocardial infarction, PCR: cardiorespiratory arrest

Fig 1 - Survival curve by Kaplan-Meier method

DISCUSSION The offered by IABP counterpulsation produces hemodynamic effects that benefit the cardiac significantly as a result of increased myocardial oxygen supply and consequent improvement of diastolic perfusion as well as the reduction in oxygen consumption due to reduced left ventricular afterload [9]. Because of these hemodynamic effects, is ideal application in post-cardiotomy cardiac dysfunction, especially if coronary hypoperfusion is 255


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suspected, their inclusion should be considered as soon as possible evidence indicating myocardial dysfunction, preferably during surgery, in order to avoid the need for excessive inotropic support [10]. Since its introduction in clinical practice, the IABP has become the most widely used means of mechanical circulatory support [11]. International registry data describe the most common indications for its use are hemodynamic support during or after cardiac catheterization (20.6%), cardiogenic shock (18.8%), weaning from CPB (16.1%), use pre surgery in high risk patients (13.0%) and refractory unstable angina (12.3%) [12]. Patients who develop low cardiac output syndrome have significantly higher prevalence of perioperative myocardial infarction and a higher operative mortality. Thus, the development of this syndrome represents revascularization or inadequate myocardial protection and can act as a marker of perioperative myocardial injury [13]. The distinction between cardiogenic shock and myocardial stunning postoperative transient, as determined in 45% of elective patients, it is important, since they are associated with different outcomes: only patients with myocardial stunning can generally have quickly suspended his inotropic support [10]. If a reversible myocardial injury occurs during a cardiac surgery, myocardial function can improve the myocardial work is reduced, the main goal of physiological circulatory assist devices [14]. The myocardial stunning is defined as a post-ischemic myocardial dysfunction prolonged, but transient, of a viable myocardium that was recovered by reperfusion, despite the cardioprotection afforded by administration of cold cardioplegia during aortic clamping, this dysfunction is a well recognized sequel of cardiopulmonary prolonged bypass [15]. Several reports have shown depressed ventricular function in the early hours after CABG: the dysfunction usually resolves within 24 to 48 hours and there seems to be dependent on changes in preload, afterload or temperature [16]. The overall mortality of patients requiring IABP in intraand postoperative ranges from 21% to 73%. The insertion of these periods, as well as the occurrence of cardiogenic shock, has been identified as an independent predictor of mortality [1]. These rates have remained relatively stable over the past 10 years despite improvements in surgical techniques, myocardial protection and medical technology, a fact which is mainly due to increased average age of the patients, the frequency of reoperations and surgery emergency, and the severity of [17]. Complications related to the use of the IAB are frequent, with a reported incidence of 8% to 18%, and mortality related directly to the device ranged between 0% and 2.6% [7]. In one case series published in Brazil, JucĂĄ et al. [17] studied 98 consecutive cases of insertion of the IAB post-

cardiac surgery, 8% describing the complications inherent in the balloon and 40% of other complications such as pneumonia, renal failure, coagulopathy and neurological diseases, and 44% of deaths. In the present study, the perioperative complication rate was high, as a major complication directly related to the IAB lower limb ischemia, observed in 5% of patients. Several previous studies have focused on identifying prognostic factors for patients treated with the IABP without agreement on preoperative determinants of survival. As a result of the variability in the indications for insertion of the IABP and differences in patient populations, there is great variability in the results reported [18]. The surgery is a major determinant of survival: the largest hospital survival and long-term patients undergoing CABG receiving IAB, compared with patients undergoing other cardiac surgical procedures, was confirmed by many studies. In a large series of cases, Torchiana et al. [19] demonstrated that the performance of CABG surgery was not associated with twice the risk of mortality. It is clear that patients with ongoing ischemia and shock do better than those with no shock and ischemia: the higher mortality of patients with valvular disease and cardiogenic shock who receive an IABP is a reflection of the fact that the problem of ventricular dysfunction is not reversible or partially reversible. Patients with deep hemodynamic persist after the insertion of the IABP are likely to survive on the use of a ventricular assist device (VAD) [1]. In the present study, the more significant that the surgery was the time of the procedure, and surgery with prolonged ischemia time associated with increased mortality, perhaps related to post-ischemic myocardial stunning cited above. The myocardial protection in all procedures performed in this series was performed using crystalloid cardioplegia St Thomas II, coronary infusion every 30 minutes and maintained hypothermia with saline in the form of shapeless semi-liquid ice in the pericardial cavity during myocardial ischemia. The lower limb ischemia is the most common complication of the use IAB reported in 8% to 42% of cases, this variation is largely dependent on the setting of ischemia and the intensity of observation of the patient. Several studies have examined risk factors for vascular complications, especially, among them women, peripheral vascular disease and diabetes, which have been identified as independent risk factors for vascular complications. Some other studies involve long-standing use of the IABP, smoking and hypertension as risk factors [1]. In a study involving 16,909 patients, 9179 underwent CABG, Ferguson et al. [12] identified the presence of peripheral vascular disease, female sex, body surface area <1.65 m 2 and age ≼ 75 years as risk factors for major complications. In this study, this definition included

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increased lower limb ischemia, severe bleeding, balloon leak or death directly attributable to the insertion of the balloon or its failure. In this study, the occurrence of acute renal failure (ARF) was a complication not directly related to the IAB most common, occurring in 35% of patients. Brito et al. [20] analyzed factors related to the occurrence of ARF postCABG, observed that the need for IABP was a risk factor, though not independent. The identification of a subgroup of high risk for low cardiac output optimization can dictate the preoperative use of diuretics, afterload reduction and / or support with IABP [2]. Miceli et al. [21] developed a score to identify high-risk patients and predict the need for insertion of the IAB in patients undergoing CABG. Multivariate analysis identified age over 70 years, degree of ventricular dysfunction, previous cardiac surgery, emergency surgery, injury, TBI, angina CCS III / IV and myocardial infarction as independent risk factors for the need for insertion of the IABP. Similar studies also exist for aortic valve surgery [22] and isolated mitral valve [2]: these scores may help in the planning of subsequent surgery and postoperative management. The definition of shock continues after cardiotomy variable but generally reflects patients who have inadequate performance after cardiac surgery, although inotropic support with IABP and [23]. Several studies indicate a correlation between hemodynamic parameters and the level of pharmacological support needed: the more inotropic drugs are required to restore hemodynamic stability, the worse the outcome [24]. The identification of the group of patients who are at increased risk of death when inserting IABP will help determine which patients may benefit from a temporary support, beyond what is offered by that device or other management strategies [18]: those patients with low cardiac output syndrome, despite the support of the IABP, the ventricular assist devices (VAD) have been used to achieve recovery of the circulatory system, with variable success, and different intentions. In some patients, this device was used as a bridge to heart transplantation, and in others as permanent replacement therapy [25]. The “IABP score,” described by Hausmann et al. [25], proved to be able to estimate survival at 30 days after 1 hour of implantation of the IAB, showing that the rapid recovery of the left ventricle predicts patient survival, suggesting that in individuals with high scores, implantation of a VAD should be considered. The parameters that make up this score are the needs of adrenaline, maximum urine output in diuretic therapy, mixed venous oxygen saturation and left atrial pressure. Another score for the same purpose was proposed by Saeed et al. [26], which, after six hours of implantation of the IABP has the power to predict survival at 30 days from the mean arterial pressure, epinephrine dose,

central venous pressure and serum lactate concentration. In general, patients at risk of low cardiac output has long history of coronary atherosclerosis with previous myocardial infarction resulting in reduced cardiac reserve, has one or more coronary revascularization and unstable, requiring emergency surgery. The incomplete revascularization and perioperative AMIs are common, in fact, previous studies showed that over two thirds of patients who die after the post-cardiotomy support and are subjected to autopsy had evidence of extensive AMI, this information is important because it allows the identification of patients at high perioperative risk, and may be used to select a device intraoperatively [27]. The AMI, trans- and postoperative period, occurs in 5% to 15% of CABG. Analysis of autopsies indicate that the majority of grafts were patent, so that the pathophysiological mechanism of perioperative AMI appears to be related to the disproportion between supply and myocardial oxygen consumption, and not with occlusion of saphenous grafts, and supports the idea there may be benefit of prophylactic IAB in CABG [9]. Small randomized trials, such as those conducted by Christenson et al. [28-32] and cohort studies have associated the inclusion of pre-operative IABP with better outcomes in high-risk patients undergoing CABG. The definition of “high risk” varies between these studies and include older age, low ejection fraction or symptomatic congestive heart failure, injury to the ECA, the second CABG surgery or urgent / emergency [11]. In recent Cochrane meta-analysis [33] observed that the evidence suggests that preoperative IABP may have beneficial effect on mortality and morbidity in specific high-risk groups undergoing CABG, however, there are many problems with the quality , reliability and validity of the tests. The available evidence is not robust enough to extend the use of the IABP for elective high-risk patients: define more precisely which groups of patients who may benefit will be the challenge for the future. Despite over 30 years of clinical use and the large scientific literature on IABP, several critical issues still need to be answered, such as the proper use and great device, its use preoperatively in high risk patients and the role of the IABP for support intra-and postoperatively on the use of VAD [1]. Patients who need the IABP form a group of very high risk for morbidity and mortality. Its use, however, allows recovering many patients from a development which would be invariably fatal. Patients who require cardiac surgery IABP may have worse outcomes than patients who receive such preoperative circulatory support: in both groups, however, after an early peak in mortality, the midterm results are characterized by a plateau survival rates [11]. Although the early mortality rate in patients who need the IABP is high, the long-term prognosis is relatively good for those who 257


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survive the immediate postoperative period [18]: patients discharged from hospital seem to have good survival, determined by the underlying disease and comorbidities [1]. The higher mortality rate after hospital discharge occurs during the first year, especially in the first three months after the operation [18.34-36], as also observed in this series. Patients who need the IABP form a group of very high risk for morbidity and mortality: in the present study, hospital mortality was 53.8% and the rate of postoperative complications of 71.3%, numbers that corroborate this claim. Using this device, however, allows many patients to recover a development which would invariably fatal, and the patient was discharged a good medium term survival.

7. Meharwal ZS, Trehan N. Vascular complications of intra-aortic balloon insertion in patients undergoing coronary revascularization: analysis of 911 cases. Eur J Cardiothorac Surg. 2002;21(4):741-7. 8. Parissis H, Leotsinidis M, Akbar MT, Apostolakis E, Dougenis D. The need for intra aortic balloon pump support following open heart surgery: risk analysis and outcome. J Cardiothorac Surg. 2010;5:20. 9. Kern M, Santanna JRM. O uso do balão intra-aórtico no préoperatório de cirurgia de revascularização miocárdica, associada à disfunção ventricular grave. Arq Bras Cardiol. 2006;86(2):97104. 10. Mebazaa A, Pitsis AA, Rudiger A, Toller W, Longrois D, Ricksten SE, et al. Clinical review: practical recommendations on the management of perioperative heart failure in cardiac surgery. Crit Care. 2010;14(2):201. 11. Dhaliwal AS, Chu D, Huh J, Ghadir M, Sansgiry S, Atluri P, et al. Prognostic impact of intra-aortic balloon pump insertion before versus after cardiac surgical intervention in a veteran population. Am J Surg. 2009;198(5):628-32. 12. Ferguson JJ 3rd, Cohen M, Freedman RJ Jr, Stone GW, Miller MF, Joseph DL, et al. The current practice of intra-aortic balloon counterpulsation: results from the Benchmark Registry. J Am Coll Cardiol. 2001;38(5):1456-62. 13. Rao V, Ivanov J, Weisel RD, Ikonomidis JS, Christakis GT, David TE. Predictors of low cardiac output syndrome after coronary artery bypass. J Thorac Cardiovasc Surg. 1996;112(1):38-51.

REFERENCES 1. Baskett RJ, Ghali WA, Maitland A, Hirsch GM. The intraaortic balloon pump in cardiac surgery. Ann Thorac Surg. 2002;74(4):1276-87. 2. Maganti M, Badiwala M, Sheikh A, Scully H, Feindel C, David TE, et al. Predictors of low cardiac output syndrome after isolated mitral valve surgery. J Thorac Cardiovasc Surg. 2010;140(4):790-6. 3. Gun C, Piegas LS. Síndrome de baixo débito no pós-operatório de cirurgia cardíaca. Rev SOCESP. 2001;11(5):1023-32. 4. Kantrowitz A, Krakauer JS, Rosenbaum A, Butner AN, Freed PS, Jaron D. Phase-shift balloon pumping in medically refractory cardiogenic shock. Results in 27 patients. Arch Surg. 1969;99(6):739-43. 5. Bregman D, Nichols AB, Weiss MB, Powers ER, Martin EC, Casarella WJ. Percutaneous intraaortic balloon insertion. Am J Cardiol. 1980;46(2):261-4. 6. Fernandes MA. Choque cardiogênico. Suporte mecânico circulatório. Rev SOCERJ. 2001;2(1):45-8.

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14. Hoy FB, Mueller DK, Geiss DM, Munns JR, Bond LM, Linett CE, et al. Bridge to recovery for postcardiotomy failure: is there still a role for centrifugal pumps? Ann Thorac Surg. 2000;70(4):1259-63. 15. Przyklenk K, Aoki A, Bellows S, Klinedinst D, Zubiate P Jr, Hale SL, et al. Stunned myocardium following prolonged cardiopulmonary bypass: effect of warm versus cold cardioplegia in the canine model. J Card Surg. 1994;9(3 Suppl):506-16. 16. Kloner RA, Przyklenk K, Kay GL. Clinical evidence for stunned myocardium after coronary artery bypass surgery. J Card Surg. 1994;9(3 Suppl):397-402. 17. Jucá FG, Moreira LFP, Carmona MJC, Stolf NAG, Jatene AD. Uso do balão intra-aórtico no choque cardiogênico no pós-operatório de cirurgia cardíaca: análise prospectiva durante 22 meses. Rev Bras Cir Cardiovasc. 1998;13(4):351-3. 18. Arafa OE, Pedersen TH, Svennevig JL, Fosse E, Geiran OR. Intraaortic balloon pump in open heart operations: 10-year follow-up with risk analysis. Ann Thorac Surg. 1998;65(3):741-7.


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19. Torchiana DF, Hirsch G, Buckley MJ, Hahn C, Allyn JW, Akins CW, et al. Intraaortic balloon pumping for cardiac support: trends in practice and outcome, 1968 to 1995. J Thorac Cardiovasc Surg. 1997;113(4):758-64.

29. Christenson JT, Simonet F, Badel P, Schmuziger M. Optimal timing of preoperative intraaortic balloon pump support in high-risk coronary patients. Ann Thorac Surg. 1999;68(3):934-9.

20. Brito DJA, Nina VJS, Nina RVAH, Figueiredo Neto JA, Oliveira MIG, Salgado JVL et al. Prevalência e fatores de risco para insuficiência renal aguda no pós-operatório de revascularização do miocárdio. Rev Bras Cir Cardiovasc. 2009;24(3):297-304.

30. Christenson JT, Badel P, Simonet F, Schmuziger M. Preoperative intraaortic balloon pump enhances cardiac performance and improves the outcome of redo CABG. Ann Thorac Surg. 1997;64(5):1237-44.

21. Miceli A, Duggan SM, Capoun R, Romeo F, Caputo M, Angelini GD. A clinical score to predict the need for intraaortic balloon pump in patients undergoing coronary artery bypass grafting. Ann Thorac Surg. 2010;90(2):522-6.

31. Christenson JT, Simonet F, Badel P, Schmuziger M. Evaluation of preoperative intra-aortic balloon pump support in high risk coronary patients. Eur J Cardiothorac Surg. 1997;11(6):1097-103.

22. Maganti MD, Rao V, Borger MA, Ivanov J, David TE. Predictors of low cardiac output syndrome after isolated aortic valve surgery. Circulation. 2005;112(9 Suppl):I448-52. 23. Rao V. Condition critical: can mechanical support prevent death due to postcardiotomy shock? J Card Surg. 2006;21(3):238-9. 24. Hagan K, Casanova-Ghosh E. Postcardiotomy cardiogenic shock: the role of ventricular assist devices. Crit Care Nurs Clin North Am. 2007;19(4):427-43. 25. Hausmann H, Potapov EV, Koster A, Krabatsch T, Stein J, Yeter R, et al. Prognosis after the implantation of an intraaortic balloon pump in cardiac surgery calculated with a new score. Circulation. 2002;106(12 Suppl 1):I203-6. 26. Saeed D, El-Banayosy A, Zittermann A, Fritzsche D, Mirow N, Morshuis M, et al. A risk score to predict 30-day mortality in patients with intra-aortic balloon pump implantation. Thorac Cardiovasc Surg. 2007;55(3):163-7. 27. Smedira NG, Blackstone EH. Postcardiotomy mechanical support: risk factors and outcomes. Ann Thorac Surg. 2001;71(3 Suppl):S60-6. 28. Christenson JT, Licker M, Kalangos A. The role of intra-aortic counterpulsation in high-risk OPCAB surgery: a prospective randomized study. J Card Surg. 2003;18(4):286-94.

32. Christenson JT, Simonet F, Badel P, Schmuziger M. The effect of preoperative intra-aortic balloon pump support in patients with coronary artery disease, poor left-ventricular function (LVEF < 40%), and hypertensive LV hypertrophy. Thorac Cardiovasc Surg. 1997;45(2):60-4. 33. Theologou T, Bashir M, Rengarajan A, Khan O, Spyt T, Richens D, et al. Preoperative intra aortic balloon pumps in patients undergoing coronary artery bypass grafting. Cochrane Database Syst Rev. 2011;(1):CD004472. 34. Mejía OAV, Lisboa LAF, Tiveron MG, Santiago JAD, Tineli RA, Dallan LAO, et al. Cirurgia de revascularização miocárdica na fase aguda do infarto: análise dos fatores preditores de mortalidade intra-hospitalar. Rev Bras Cir Cardiovasc. 2012;27(1):66-74. 35. Anderson AJPG, Barros Neto FXR, Costa MA, Dantas LD, Hueb AC, Prata MF. Preditores de mortalidade em pacientes acima de 70 anos na revascularização miocárdica ou troca valvar com circulação extracorpórea. Rev Bras Cir Cardiovasc. 2011;26(1):69-75. 36. Oliveira EL, Westphal GA, Mastroeni MF. Características clínico-demográficas de pacientes submetidos a cirurgia de revascularização do miocárdio e sua relação com a mortalidade. Rev Bras Cir Cardiovasc. 2012;27(1):52-60.

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ORIGINAL ARTICLE

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Calcium dobesilate may improve hemorheology in patients undergoing coronary artery bypass grafting Dobesilato de cálcio pode melhorar hemorreologia em pacientes submetidos à cirurgia de revascularização miocárdica

Kazim Besirli1, Birsen Aydemir2, Caner Arslan1, Ali Riza Kiziler3, Emir Canturk4, Bekir Kayhan4

DOI: 10.5935/1678-9741.20120057 Abstract Background: Calcium dobesilate is an angioprotective agent that has positive effects on hemorheological parameters. It is an antioxidant that increases endothelialderived vasodilator substance secretion, there are none that analyze its effects during the postoperative period of patients undergoing myocardial revascularization. Objective: We aimed to determine the effects of calcium dobesilate on hemorheological parameters, such as reduced glutathione and malondialdehyde in patients with ischemic heart disease undergoing myocardial revascularization in the postoperative period. Methods: One hundred and thirty-four patients operated for coronary heart disease were included in this study. Hemorheological, oxidant and antioxidant parameters were measured two days after surgery and after a period of treatment with calcium dobesilate. Then, 500 mg of calcium dobesilate was given twice a day to one group of 68 patients for three months. The control group was composed of 66 patients who did not receive this medication. Results: The increase in the erythrocyte deformability index was found to be significant compared with both the pretreatment values and with the 1st and 2nd values of the control group after calcium dobesilate administration, whereas there were no significant changes in blood viscosity, glutathione (GSH) or malondialdehyde (MDA) values after

1. Istanbul University, Cerrahpasa Medical Faculty, Cardiovascular Surgery Department, Istanbul, Turkey. 2. Istanbul University Cerrahpasa Medical Faculty, Department of Biophysics, Istanbul, Turkey. 3. Namik Kemal University, Medical Faculty, Biophysics Department, Tekirdag, Turkey. 4. TDV 29 Mayis Hospital, Cardiovascular Surgery Department, Istanbul, Turkey.

RBCCV 44205-1379 the calcium dobesilate administration. The same improvement in the CCS class was observed in patients regardless of they received the calcium dobesilate treatment. Conclusion: In the present investigation, the same improvement in the CCS class was observed in patients regardless of they received the calcium dobesilate treatment. Improvements with calcium dobesilate were statistically significant only in the increase in erythrocyte flexibility. Descriptors: Coronary artery disease. Atherosclerosis. Coronary artery bypass.

Resumo Antecedentes: O dobesilato de cálcio é um agente angioprotetor que tem efeitos positivos sobre os parâmetros hemorreológicos. É um antioxidante que aumenta a secreção endotelial derivada da substância vasodilatadora, não há nada que analisar os seus efeitos durante o período pósoperatório de pacientes submetidos a revascularização do miocárdio. Objetivo: Nosso objetivo foi determinar os efeitos de dobesilato de cálcio sobre os parâmetros hemorreológicos, tais como glutationa reduzida e malondialdeído em pacientes com doença cardíaca isquêmica submetidos a revascularização do miocárdio no pós-operatório.

Correspondence address Birsen Aydemir Istanbul University - Department of Biophysics Fatih - Cerrahpasa Medical Faculty – 34098. Istanbul, Turkey E-mail: birsenay2001@yahoo.com Work performed at Istanbul University Cerrahpasa Medical Faculty Department of Biophysics, Istanbul, Turkey. Article received on January 25th, 2012 Article accepted on April 30th, 2012

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Abbreviations, acronyms & symbols BHT BV BV CCS CCS DTNB EDI EDTA EF GSH Hct MDA PV ROS TBARS TCA

Butylhydroxytoluene Blood viscosity Blood viscosity Canadian Cardiac Society Canadian Cardiac Class Nitrobenzoic acid Erythrocyte deformability index Ethylenediaminetetraacetate Ejection fraction Glutathione Hematocrit Malondialdehyde Plasma viscosity Reactive oxygen species Thiobarbituric acid-reactive substances Trichloroacetic acid

Métodos: Cento e trinta e quatro pacientes operados por doença cardíaca coronária foram incluídos neste estudo. Parâmetros de oxidante, hemorreológicos e de antioxidantes foram medidos dois dias após a cirurgia e após um período

INTRODUCTION Myocardial ischemia and infarction are the ultimate results of coronary artery disease . Hemorheological factors that can worsen tissue’s ischemia may accentuate the disease. Fibrinogen has a pronounced effect on plasma viscosity (PV). Hematocrit (Hct) and PV are the most important components of blood viscosity (BV) and PV also plays an important role in the atherosclerotic process [1,2]. Atherogenesis is further accelerated by an impaired blood flow that is closely related BV [3]. It has been shown that drugs that may increase erythrocyte flexibility decreased pain in critical limb ischemia during rest [4]. Reactive oxygen species (ROS) may result in cell injury and cause oxidative damage to lipids which is an important component of atherosclerotic cardiovascular heart disease. Erythrocytes reduce glutathione (GSH), which is an endogenous mechanism of oxidant inactivation; accordingly, once formed, ROS oxidizes GSH which is then released outside the cells and prevents oxidative damage [5]. Calcium dobesilate which is a veno-tonic drug, has long been used effectively in many countries for the treatment of diabetic retinopathy, chronic venous insufficiency and symptoms of hemorrhoidal attacks. In recent years, it has also been shown that calcium dobesilate can improve hemorheology and microcirculation and possesses antioxidant, and antiplatelet properties, as described for its clinical and experimental use [1,6]. However, there are no reports analyzing the effects of calcium dobesilate in the

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de tratamento com o dobesilato de cálcio. Em seguida, 500 mg de dobesilato de cálcio foi administrado duas vezes por dia para um grupo de 68 pacientes durante três meses. O grupo controle foi composto por 66 pacientes que não receberam essa medicação. Resultados: O aumento do índice de deformabilidade dos eritrócitos foi considerado significativo comparado com ambos os valores pré-tratamento e com os 1º e 2º valores do grupo controle após a administração dobesilato de cálcio, enquanto que não houve alterações significativas na viscosidade do sangue, na glutationa (GSH) ou malondialdeído (MDA) após a administração dobesilato de cálcio. A mesma melhoria na classe CCS foi observada em pacientes independentemente de terem recebido tratamento com dobesilato de cálcio. Conclusão: Na presente investigação, a mesma melhora na classe CCS foi observada em pacientes independentemente de terem recebido o tratamento com dobesilato de cálcio. Descritores: Doença da artéria coronariana. Aterosclerose. Ponte de artéria coronária.

postoperative period of patients undergoing myocardial revascularization. This study aimed, therefore, to investigate whether administration of calcium dobesilate would exhibit any beneficial effects on hemorheology and oxidative stress in the postoperative period of patients undergoing myocardial revascularization. METHODS A total of 134 subjects (110 men and 24 women) who underwent coronary bypass grafting were included in the present study. Patient selection was non-randomized. Sixtyeight subjects (58 men and 10 women, mean age: 54.6 ± 6.1 years) received 500 mg calcium dobesilate twice a day following the first blood samples that were taken 2 days after surgery. Sixty-six subjects (52 men and 14 women, mean age: 55.4 ± 5.2 years) who did not take this medication comprised the control group. All of the coronary bypass operations were performed on pump in the study group. Preoperatively, in the group receiving calcium dobesilate, 32 patients had CCS 4 status and 36 patients had CCS 2-3 status, whereas in the control group, 30 patients had CCS 4 status and 36 patients had CCS 2-3 status. Regarding cardiovascular risk factors for all patients, 98 patients were ex-smokers (they had stopped smoking just before the operation), 50 had a family history of cardiovascular disease, hypercholesterolemia was present in 71, diabetes mellitus was present in 29 and essential hypertension was present in 63. Twenty-five patients had been taking statins preoperatively. The left ventricular ejection fraction in 70 261


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patients was >50%, 35%-50% in 44 patients and <35% in 20 patients. Four-vessel bypasses had been performed in 18 patients, three-vessel bypasses had been performed in 34, two-vessel bypasses had been performed in 66 and a onevessel bypass had been performed in 16 patients (Table 1). This study conforms with the Helsinki Declaration of the World Medical Association, and the Ethics Committee of the Cerrahpaºa Medical Faculty approved the research protocol. Informed consent was obtained from each patient after receiving verbal and written information about the study. Three months after the surgery, 10 patients in the calcium dobesilate group had CCS 1-2 status, whereas eight patients in the control group had CCS 1-2 status. Pleural effusions were observed in two patients in the calcium dobesilate group and in three patients in the control group. Postoperative atrial fibrillations developed in five patients in the calcium dobesilate group and in four patients in the control group. No early or late mortality was observed in either group. Blood samples were drawn from the patients’ antecubital veins after 12-hour fasting. Initial blood samples were taken two days after the operation, and the second samples were taken 3 months later. In this period, 68 patients had taken calcium dobesilate 500 mg twice a day and a placebo was given to the 66 patients in the control group. Routine blood counts (for Hct) were determined with ethylenediaminetetraacetate (EDTA)-anticoagulated blood samples by an electronic counter (Medonic CA 570, Sweden). To determine the erythrocyte deformability index (EDI), plasma and blood viscosity, erythrocyte and plasma malondialdehyde (MDA) and GSH, blood samples were collected in vacutainer tubes containing EDTA without

anticoagulant. Fibrinogen was collected in vacutainer tubes containing sodium oxalate. Plasma samples were obtained by centrifugation at 1000 x g for 20 min and stored at –70°C. The erythrocytes were prepared with whole blood centrifugation for 5 min at 1000 x g and obtained after washing in a 0.9% NaCl solution twice and then removed for measurement. Lipid peroxide levels were measured in the plasma and erythrocytes using a thiobarbituric acid-reactive substances (TBARS) assay, which monitors MDA production [7]. Briefly, to a 200 µl sample containing erythrocyte pellet and plasma, 800 µl phosphate buffer (pH 7.4), 25 µl butylhydroxytoluene (BHT) (88 mg/10 ml absolute alcohol) and 500 µl of 30% trichloroacetic acid (TCA) was added and mixed. After 2 h incubation at 20 °C, the mixture was centrifuged (400 g) for 15 min. After this, 1 ml supernatant was added to each tube, followed by the addition of 75 µl of 0.1 M EDTA and 250 µl of 1% thiobarbituric acid (TBA). The tubes, which had teflonlined screw caps, were incubated at 90°C in a water bath for 15 min and cooled to room temperature. The optical density was measured at 532 and 600 nm by ultraviolet-visible spectrophotometry for the erythrocyte MDA and at 532 nm for the plasma MDA and tissue MDA concentrations (Shimadzu UV-1601, Tokyo, Japan). The MDA level was determined using the molar absorption coefficient of the MDA, 1.56x105 M-1cm-1 at 532 nm. The GSH concentration was determined in the erythrocytes by a modified coupled optical test system [8]. In this system, GSH is oxidized by 5,5’dithiobis-2 nitrobenzoic acid (DTNB) and then reduced by GSH reductase with NADPH as the hydrogen donor. The oxidation of GSH by DTNB was detected photometrically by a change in the absorption at 412 nm. Briefly, to a 100 µl

Table 1. Characteristics of patients in calcium dobesilate group and control group. Number (Male/Female) Age Mean

Calcium Dobesilate Group 68 (58/10) 54.6 ± 6.1 Class 4; 32,

Control Group 66 (52/14) 55.4 ± 5.2 Class 4; 30,

Class 2-3; 36 Class 1-2; 10 3 5 8/16/32/12 36/20/12 patients 52 30 41 14 37 12

Class 2-3; 36 Class 1-2; 8 2 4 10/18/34/4 34/24/8 patients 46 20 30 15 26 13

Preop CCS Class Postop CCS Class (3 months after operation) Pleural effusion Atrial fibrillation Number of bypasses (4/3/2/1) EF (>50%/50%-35%/<35%) Ex-smoker Family history Hypercholestrolemia Diabetes mellitus Essential hypertension Preop statin use

0.852

EF = Ejection Fraction; CCS = Canadian Cardiac Society

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P 0.326 0.761

0.661 0.673 0.765 0.224 0.551 0.376 0.098 0.085 0.764 0.082 0.761


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sample, 150 µl of 5% sulfosalicylic acid (w/v) was added to induce lysis. Twenty µl of lysate was added to 980 µl of reaction buffer (100 nM potassium phosphate buffer, 1 mM NADPH, 0.5 mM DTNB, 0.5 U GSH reductase pH 7.4). The change in absorption was recorded at 412 nm with ultraviolet-visible spectrophotometry (Shimadzu UV-1601, Tokyo, Japan). The GSH level was determined using the molar absorption coefficient of GSH at 412 nm 13.6x10-4 M1 cm-1. The BV and the PV were measured using a Harkness Capillary Viscometer (Coulter Electronics Ltd, Ser. No: 6083, England) at 37 (relative viscosity) [9]. Erythrocyte deformability was determined by a stroboscopic centrifugal method. Plasma fibrinogen levels were measured using calorimetric kits (Sigma Chemical and Fibri-Prest, Diagnostica Stago, France).

analysis of variance and Tukey’s honestly different significance test were used to evaluate the significance of differences in the parameters of age, whole blood viscosity, plasma viscosity, the erythrocyte deformability index, erythrocyte reduced glutathione levels, erythrocyte malondialdehyde levels, plasma malondialdehyde levels, fibrinogen levels and Hct among both the pretreatment and posttreatment values in the calcium dobesilate group and the first and second values in the control group. P< 0.05 was considered statistically significant. RESULTS The mean values of BV, PV, Hct, EDI, plasma fibrinogen, erythrocyte GSH, erythrocyte MDA and plasma MDA are shown in Table 2 and 3. The EDI values after 3 months of medication with calcium dobesilate were found to be statistically significantly higher than both those before treatment (P<0.001) and the first and second values in the control group (P<0.01 and P<0.01, respectively). The decrease in BV, PV, Hct and erythrocyte GSH and the increase in plasma fibrinogen, erythrocyte MDA and plasma MDA values were not statistically significant.

Statistical analysis All results are expressed as the mean and standard deviation (SD). The statistical significance of differences was determined by SPSS version 15.0 for Windows (SPSS, Chicago, IL, USA). Patient characteristics were compared using Pearson Chi square test for categorical data. The Student’s t-test, Mann-Whitney U test, the one–way

Table 2. BV, PV, Hct and EDI values before and after calcium dobesilate treatment in the calcium dobesilate group and first and second values after 3 months in the control group. Parameters

Calcium Dobesilate Group (Pretreatment values)

Calcium Dobesilate Group (Postreatment values)

3.38±0.44

3.14±0.44

0.105

3.24±0.12

0.731

3.13±0.15

0.998

0.463

0.065

0.656

1.39±0.25

1.38±0.38

0.996

1.35±0.12

0.982

1.38±0.09

0.998

0.926

0.998

0.955

33.22±1.24

32.76±1.44

0.987

33.67±1.74 0.453

32.42±1.59 0.804

0.677

0.590

0.059

9.82±0.94

11.13±0.76

0.001

10.16±1.00

10.19±0.77

0.596

0.502

0.998

a

P

Control Group (First values)

b

P

Control Group (Second values)

c

P

d

P

e

P

f

P

Whole blood viscosity (m.Pas) Plasma viscosity (m.Pas) Hct (%) Erythrocyte deformability index 0.01

0.01

(%Hct min-1)

The values are given as mean± SD. a P = pretreatment values in calcium dobesilate group compared with posttreatment values in calcium dobesilate group (ANOVA, Tukey’s Range [HSD] test); bP = first values in the control group compared with posttreatment values in the calcium dobesilate group; cP = second values in the control group compared with posttreatment values in the calcium dobesilate group; dP = first values in the control groupcompared with pretreatment values in the calcium dobesilate group; eP = second values in the control group compared with pretreatment values in the calcium dobesilate group; fP = first values in the control group compared with second values in the control group

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Table 3. Fibrinogen, erythrocyte GSH, erythrocyte MDA and plasma MDA values before and after calcium dobesilate treatment in the calcium dobesilate group and first and second values after three months in the control group. Parameters

Calcium Dobesilate Group (Pretreatment values) Fibrinogen (mg/dL) 276.76±75.21 Erythrocyte GSH (mmol/g Hb) 15.59±2.03 Erythrocyte MDA (nmol MDA/g Hb) 3.05±0.63 Plasma MDA (nmol/mL) 5.88±1.05

Calcium Dobesilate Group (Postreatment values) 278.82±84.65 14.30±2.39 3.15±0.54 6.04±1.31

a

P

Control Group (First values)

b

P

Control Group (Second values)

0.998 265.50±24.34 0.875 246.25±32.67 0.265 14.74±2.24 0.936 14.57±2.79 0.975 3.09±0.40 0.964 3.23±0.48 0.946 5.92±0.55 0.969 6.02±0.39

c

P

0.263 0.935 0.956 0.998

d

P

0.920 0.496 0.998 0.998

e

P

0.319 0.504 0.767 0.956

f

P

0.632 0.998 0.697 0.977

The values are given as mean± SD. a P = pretreatment values in calcium dobesilate group compared with post treatment values in calcium dobesilate group (ANOVA, Tukey’s Range [HSD] test); bP = first values in the control group compared with posttreatment values in the calcium dobesilate group; cP = second values in the control group compared with post treatment values in the calcium dobesilate group; dP = first values in the control group compared with pretreatment values in the calcium dobesilate group; eP = second values in the control group compared with pretreatment values in the calcium dobesilate group; fP = first values in the control group compared with second values in the control group

DISCUSSION In advanced atherosclerotic disease, the fluidity of the bloodstream is decreased. The classic hemorheological parameters, BV and PV, are higher than in healthy persons. In atherosclerotic disease, with its critically decreased pressure gradients and exhausted vascular reserves, an increased structural viscosity leads to reduced organ perfusion [10]. Approximately 40% of all vascular events can be explained by the classical risk factors for atherosclerotic disease [11]. In the early stages of atherosclerotic vascular disease, endothelium-derived relaxing factor release is diminished, and, in the later stages, plaques or stenosis cause vascular diameter regulation to deteriorate [12]. In patients for whom these problems cannot be modified, only hemorheological therapeutic interventions remain [12]. Rheological parameters, such as fibrinogen concentration, plasma viscosity and leukocyte count, are important risk factors for ischemic heart disease [12-14]. Oxidation and the production of free radicals are an integral part of the human metabolism [15]. Lipid oxidation is a significant, harmful consequence of ROS formation, as it reflects irreversible oxidative changes in membranes [1619]. Plasma MDA levels are one of the most commonly used markers of lipid peroxidation. Increased venous concentration of MDA has been found in patients subjected to cardiac surgery [20-22]. However, an MDA concentration in systemic blood may reflect changes unrelated to the cardiac oxidative stress (prostanoid synthesis) activity of aldehyde-dehydrogenase and aldose reductase [23-25]. Despite calcium dobesilate therapy, an increase in erythrocyte and plasma MDA levels and a decrease in erythrocyte GSH in the present study shows that calcium dobesilate is not an effective antioxidant, which is in contrast to the studies that have demonstrated its antioxidant properties [26]. 264

It has been shown that calcium dobesilate improves hemorheology by reducing BV, PV and Hct and potentiating fibrinolysis in diabetic patients [27]. The fact that calcium dobesilate decreases vascular permeability indicates that it plays a role in causing fluid retention in the vascular system, causing hemodilution [28]. An earlier and more rapid improvement was observed in patients with myocardial infarction who were taking CLS 2210 (a new formulation of calcium dobesilate) [29]. In an experimental study, it was shown that the same drug reduced mortality in rats after the occlusion of a coronary artery [30]. In this study, the decrease in the BV and PV and the increase in the plasma fibrinogen level in patients were not significant after 3 months of doxium medication. This increase was likely due to the increased hepatic production of fibrinogen related to postoperative stress [31]. The most beneficial effect of the calcium dobesilate treatment in our patient group was the significant increase in EDI when compared with the control group. Although the decrease in BV and PV values were not statistically significant after calcium dobesilate treatment in our study, a decreased BV is beneficial for coronary heart disease patients because a high BV could cause thrombosis by decreasing the dilution of activated coagulation factors and retarding the inflow of clotting inhibitors [3]. Elevations in PV and BV may aggravate hypoxia by increasing the resistance to flow in patients with peripheral arterial occlusive disease [32]. Deformability enables erythrocytes to pass through the nutritive capillaries, which have a diameter approximately half of theirs, and to supply oxygen to tissues. Erythrocytes lose these functions and become more susceptible to hemolysis if their flexibility falls below a threshold level [33]. In the present study, the only statistically significant result showing improvement because of calcium dobesilate administration was the increase in the flexibility of the RBC. It may also somewhat


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improve coronary microcirculation when used as an adjunctive treatment in patients with ischemic heart disease, but it is illogical to relate the improvements in the CCS class to this drug in the calcium dobesilate group, because the same improvements were also observed in the control group, and all the patients were revascularized as much as possible.

7. Jain SK, Rains J, Jones K. Effect of curcumin on protein glycosylation, lipid peroxidation, and oxygen radical generation in human red blood cells exposed to high glucose levels. Free Radic Biol Med. 2006;41(1):92-6.

Limitations There are some limitations to our study. It was not blinded or randomized. We were also unable to administer calcium dobesilate to patients preoperatively because of the hospitalization policy. We were also unable to discontinue patients’ anti-anginal and antiplatelet drugs while administering calcium dobesilate and could therefore not prevent interactions between these drugs.

9. Kiziler AR, Aydemir B, Gulyasar T, Unal E, Gunes P. Relationships among iron, protein oxidation and lipid peroxidation levels in rats with alcohol-induced acute pancreatitis. Biol Trace Elem Res. 2008;124(2):135-43.

CONCLUSION In the present investigation, the same improvements in the CCS class were observed in patients regardless of whether they received calcium dobesilate. Calcium dobesilate was effective only for the increase in red blood cell flexibility.

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14. Yarnell JW, Baker IA, Sweetnam PM, Bainton D, O’Brien JR, Whitehead PJ, et al. Fibrinogen, viscosity and white cell blood cell count are major risk factors for ischemic heart disease. Circulation. 1991;83(3):836-44.

2. Vulpis V. Endothelin, microcirculation and hemorheology. Clin Hemorheol Microcirc. 1999;21(3-4):273-6.

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3. Sloop GD. A critical analysis of the role of cholesterol in atherogenesis. Atherosclerosis. 1999;142(2):265-8. 4. The European Study Group. Intravenous pentoxyifylline for the treatment of chronic critical limb ischemia. Eur J Vasc Endovasc Surg. 1995;9(4):426-36. 5. Tanriverdi H, Evrengul H, Kuru O, Tanriverdi S, Seleci D, Enli Y, et al. Cigarette smoking induced oxidative stress may impair endothelial function and coronary blood flow in angiographically normal coronary arteries. Circ J. 2006;70(5):593-9. 6. Plessas CT, Souras S, Karayannacos PE, Plessas ST, Dontas I, Kotsarelis D, et al. Pharmacokinetic interaction in beagle dogs of antiplatelet drugs: acetylsalicylic acid, dipyridamole and calcium dobesilate. Eur J Drug Metab Pharmacokinet. 1989;14(1):79-83.

16. Ambrosio G, Flaherty JT, Duilio C, Tritto I, Santoro G, Elia PP, et al. Oxygen radicals generated at reflow induce peroxidation of membrane lipids in reperfused hearts. J Clin Invest. 1991;87(6):2056-66. 17. Lucas DT, Szweda LI. Cardiac reperfusion injury: aging, lipid peroxidation, and mitochondrial dysfunction. Proct Natl Acad Sci U S A. 1998;95(2):510-4. 18. Romaschin AD, Rebeyka I, Wilson GJ, Mickle DA. Conjugated dienes in ischemic and reperfused myocardium: an in vivo chemical signature of oxygen free radical mediated injury. J Mol Cell Cardiol. 1987;19(3):289-302. 19. Romaschin AD, Wilson GJ, Thomas U, Feitler DA, Tumiati L, Mickle DA. Subcellular distribution of peroxidized lipids in

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20. Hadjinikolaou L, Alexiou C, Cohen AS, Standbridge Rde L, McColl AJ, Richmond W. Early changes in plasma antioxidant and lipid peroxidation levels following coronary artery bypass surgery: a complex response. Eur J Cardiothorac Surg. 2003;23(6):969-75. 21. Lassnigg A, Punz A, Barker R, Keznickl P, Manhart N, Roth E, et al. Influence of intravenous vitamin E supplementation in cardiac surgery on oxidative stress: a double-blinded, randomized, controlled study. Br J Anaesth. 2003;90(2):148-54. 22. Paraskevaidis IA, Iliodromitis EK, Vlahakos D, Tsiapras DP, Nikolaidis A, Marathias A, et al. Deferoxamine infusion during coronary artery bypass grafting ameliorates lipid peroxidation and protects the myocardium against reperfusion injury: immediate and long-term significance. Eur Heart J. 2005;26(3):263-70. 23. Capdevila JH, Falck JR, Haris RC. Cytochrome P450 and arachidonic acid bioactivation. Molecular and functional properties of the arachidonate monooxygenase. J Lipid Res. 2000;41(2):163-81. 24. Shinmura K, Bolli R, Liu SQ, Tang XL, Kodani E, Xuan YT, et al. Aldose reductase is an obligatory mediator of the late phase of ischemic preconditioning. Circ Res. 2002;91(3):240-6. 25. Siu GM, Draper HH. Metabolism of malonaldehyde in vivo and in vitro. Lipids. 1982;17(5):349-55. 26. Rota R, Chiavaroli C, Garay RP, Hannaert P. Reduction of

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ORIGINAL ARTICLE

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Results of aortic valve surgery in patients over 75 years old, at 4.5 years of follow-up Resultados da cirurgia por estenose aórtica em pacientes acima de 75 anos, em 4,5 anos de seguimento

Ana Paula Tagliari1, Fernando Pivatto Júnior2, Felipe Homem Valle3, João Ricardo Michelin Sant’Anna2, Paulo Roberto Prates2, Ivo Abrahão Nesralla2, Renato Abdala Karam Kalil2

DOI: 10.5935/1678-9741.20120043 Abstract Background: The increased longevity elevated the frequency of elderly requiring surgery, among them the correction of aortic stenosis. Objectives: To evaluate medium-term mortality, need for reoperation for valve replacement and valve complications [systemic thromboembolism (STE) and prosthetic endocarditis (PE)] in patients over 75 years old who had undergone surgery for aortic stenosis. Methods: Retrospective study of 230 patients from 2002 to 2007. Mean age was 83.4 years and 53% were male. The prevalence of hypertension was 73.2%, atrial fibrillation 17.9% and previous cardiac surgery 14.4%. Another cardiac procedure was associated in 39.1% of the cases. Results: In a mean follow-up of 4.51 years the overall survival of the population studied was 57.4%. Death in the immediate postoperative period occurred in 13.9% (9.4% in the isolated aortic stenosis surgery group vs. 20.9% when another procedure was associated). Deaths in the medium term occurred in 28.7% of the patients (25.0% vs. 34.4%), with 34 of these because of cardiovascular causes. There

RBCCV 44205-1380 were 6 cases of PE, 8 cases of STE and 6 reoperations. The predictors of mortality were ischemia time >90 min (OR 1.99 95% CI 1.06-3.74), ejection fraction <60% (OR 1.76 95% CI 1.10-2.81) and prior stroke (OR 2.43 95% CI 1.185.30). Conclusion: Although the immediate surgical risk of the elderly is high, survival rates for surgical treatment of patients over 75 years old are acceptable and allow this intervention. The prognosis is worse especially because of the association with coronary artery disease. Descriptors: Aortic valve stenosis. Mortality. Morbidity. Aged.

Resumo Introdução: O aumento da expectativa de vida da população tem levado à maior necessidade de intervenções cirúrgicas sobre a valva aórtica. Objetivos: Avaliar a mortalidade precoce e a médio prazo, a necessidade de reoperação para troca valvar e complicações

1. Academic Medicine, Federal University of Rio Grande do Sul, Scientific Initiation Scholarship, Porto Alegre, Brazil. 2. Cardiovascular Surgeon, Institute of Cardiology of Rio Grande do Sul / University Foundation of Cardiology, Porto Alegre, Brazil. 3. Degree in medicine, Institute of Cardiology of Rio Grande do Sul / University Foundation of Cardiology, Porto Alegre, Brazil.

Correspondence address Ana Paula Tagliari Av. Princesa Isabel 370 – Bairro Santana – Porto Alegre, RS, Brazil – Zip code 90620-000 E-mail: aninhatagliari@yahoo.com.br

Study conducted at the Institute of Cardiology of Rio Grande do Sul/ University Foundation of Cardiology, Porto Alegre, Brazil.

Article received on February 28th, 2012 Article approved on May 7th, 2012

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Abbreviations, acronyms & symbols C VA CABG COPD AS IE EF HBP HF BMI NYHA ST

Cerebral Vascular Accident (Stroke) Coronary Artery Bypass Graft Surgery Chronic obstructive pulmonary disease Aortic stenosis Infective endocarditis Ejection fraction High blood pressure (Hypertension) Heart failure Body mass index New York Heart Association Systemic thromboembolism

valvares [tromboembolismo sistêmico (TES) e endocardite infecciosa em prótese (EI)] em pacientes acima de 75 anos submetidos a cirurgia de estenose aórtica. Métodos: Estudo retrospectivo de 230 casos, operados no período de 2002 a 2007. A idade média foi de 83,4 anos, sendo 53% do sexo masculino, 73,2% hipertensos, 17,9% portadores de fibrilação atrial e 14,4% com cirurgia cardíaca prévia.

INTRODUCTION The prevalence of cardiovascular disease is considerably higher in elderly patients, affecting approximately 40% of the elderly and constituting the main cause of death. Because aortic stenosis (AS) is a prevalent condition among older people, affecting about 5% of octogenarians [1,2] and causing very poor prognosis, increased life expectancy of the population has led to increased need for surgical interventions on the aortic valve [3]. In Brazil, the elderly account for 10.8% of the population and approximately 26.7% of these have 75 years or more [4]. At the meeting of this progressive increase in the elderly population, the medical literature has demonstrated the growing number of patients older than 75 years operated in major heart surgery centers, emphasizing the valve replacement. The natural evolution of patients with AS is associated with a long latency period, during which the severity of stenosis is only mild to moderate and survival is similar to that of the general population in that age group. However, since the symptoms are present survival decreases dramatically [5,6]. 268

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Outro procedimento cardíaco esteve associado em 39,1% dos casos. Resultados: Em 4,51 anos de seguimento médio, a sobrevida geral foi de 57,4%. Ocorreram 13,9% óbitos intra-hospitalares (9,4% no grupo cirurgia de estenose aórtica isolada vs. 20,9% quando outro procedimento cirúrgico foi associado) e 28,7% óbitos após a alta hospitalar (25,0% vs. 34,4%), com 34 destes por causas cardiovasculares. Ocorreram seis casos de EI, oito casos de TES e seis reoperações para troca valvar. Os preditores de mortalidade geral foram: tempo de isquemia >90 min (RC 1,99 IC 95% 1,06-3,74), fração de ejeção <60% (RC 1,76 IC 95% 1,10-2,81) e acidente vascular encefálico prévio (RC 2,43 IC 95% 1,18-5,30). Conclusão: Ainda que o risco cirúrgico imediato de idosos seja elevado, as taxas de sobrevida referentes ao tratamento cirúrgico em pacientes acima de 75 anos são aceitáveis e permitem essa intervenção. O prognóstico é agravado, sobretudo, pela associação com doença arterial coronariana. Descritores: Estenose da valva aórtica. Mortalidade. Morbidade. Idoso.

Recent studies have shown that although the postoperative morbidity is higher in patients over 80 years, the late postoperative mortality is similar to younger patients, with 2-year survival comparable to that of the general population, matched for age and gender [7-9]. In a previous paper we reported a hospital mortality of elderly patients with varying degrees of risk, in the period prior to the introduction of percutaneous methods. To contribute to better evaluation of surgical outcomes, it is appropriate to report the evolution of these patients [10]. The objective of this study is to evaluate the mediumterm mortality, and reoperation for valve replacement and the occurrence of valvular complications [systemic thromboembolism (ST) and infective endocarditis (IE) prosthesis] in patients aged 75 years undergoing surgery by AS alone or combined with other injuries. METHODS Retrospective study of consecutive case series. A total of 1873 valve procedures performed from January 2002 to December 2007, 230 (12.3%) were in people over 75 years undergoing cardiac surgery by AS, in a reference hospital in cardiology.


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Data were collected directly from patients’ records, entered and analyzed with SPSS 18.0. Follow-up was conducted through telephone contact and consultation with medical records, and checked one last time in the first quarter of 2011. Failing these, he was made consulting the Register of Deaths of the Health Secretariat of Rio Grande do Sul, which revealed the existence of deaths among patients not contacted, as well as their causes. The study included the following preoperative variables: age, sex, obesity, hypertension (HBP), renal dysfunction, atrial fibrillation, previous cardiac surgery, ejection fraction (EF) of the left ventricle less than 60.0% severe lesion of the mitral valve associated cerebrovascular accident (CVA) prior, current smoking, and functional class by New York Heart Association (NYHA) III / IV. The intraoperative variables were evaluated: cardiopulmonary bypass time, ischemia time, surgery (conservative surgery / valve replacement) and associated surgery. The term conservative surgery refers to the performance of surgical valvuloplasty with debridement of calcium. In the preoperative clinical characteristics, the definition of obesity was performed by calculating the body mass index (BMI), being considered obese individuals with BMI ≥ 30.0 kg / m². Patients who had a history of hypertension and were in regular use of medication (s) antihypertensive (s) were considered as having hypertension. Renal dysfunction pre-or post-operative was defined as serum creatinine greater than 2.0 mg / dl. The preoperative atrial fibrillation was defined by the presence of atrial fibrillation on resting electrocardiogram preoperatively. The classification of heart failure (HF) followed the criteria established by the NYHA. Previous stroke was defined as the presence of previous history of stroke, neurological disorders associated with localized. The low cardiac output was considered hemodynamic instability requiring

vasoactive drugs, with or without the use of intra-aortic balloon. Hospital mortality was defined as any death occurring during hospitalization of the patient, regardless of its duration. Since mortality after hospital discharge only took into account the deaths occurred after hospital discharge (including early deaths - the time of hospital discharge until one year mean follow-up and deaths in the medium term from one year mean follow-up after hospital discharge), and overall mortality the sum of the previous two. Cardiovascular deaths were analyzed only for the cases of mortality after hospital discharge and the occurrence of valvular complications. Considering the methodology of this retrospective study, it would be natural to expect some loss of data and patients who could not be found. These losses totaled 15.65% of the patients initially enrolled, resulting from the abandonment of outpatient care and / or change of address and telephone number. The descriptive analysis for categorical variables was performed by the distribution of absolute and relative frequency, and for quantitative as mean, standard deviation and median, as indicated. The description of the actuarial survival was performed by Kaplan-Meier method. The predictors of mortality were analyzed by Cox regression and those that were significant in univariate analysis or had clinical relevance were subsequently adjusted in the multivariate Cox confidence interval of 95% was calculated when deemed appropriate, should be provided between parentheses. The level of significance for all tests was 5%. This study has no external source of financing; its financial support consists only of scientific initiation scholarship from CNPq and FAPERGS. This study was approved by the Ethics Committee of the institution where it was performed (UP 4580/10).

Table 1. Preoperative clinical characteristics of the sample. Variable

Total population n=230 156 (68.7%) HBP 103 (44.8%) NYHA III/IV Functional Class Obesity 34 (15.9%) Ejection fraction < 60,0 % 62 (27.0%) Atrial fibrilation 41 (17.9%) Previous heart surgery 32 (14.4%) COPD 30 (13.0%) Severe mitral valve injury 18 (7.8%) Current smoking 17 (7.4%) Current CVA 15 (6.5%) 8 (3.5%) Kidney dysfunction

Another surgery associated n=90 65 (72.22%) 38 (42.22%) 12 (13.33%) 28 (31.11%) 16 (17.77%) 11 (12.22%) 14 (15.55%) 14 (15.55%) 8 (8.88%) 7 (7.77%) 3 (3.33%)

AS Surgery alone n=140 91 (65.0%) 65 (46.42%) 22 (15.71%) 34 (24.28%) 25 (17.85%) 21 (15.0%) 16 (11.42%) 4 (2.85%) 9 (6.42%) 8 (5.71%) 5 (3.57%)

P 0.172 0.486 0.606 0.226 0.982 0.547 0.531 0.001 0.491 0.504 0.319

CVA = Stroke, COPD = Chronic obstructive pulmonary disease; AS = aortic stenosis; HBP = High blood pressure, NYHA = New York Heart Association

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RESULTS

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The patients’ ages ranged from 75 to 94 years, mean (± SD) 79.5 ± 3.7 years, whereas 122 (53%) were male and 189 (82.17%) already had some degree of IC, with 44.8% (n = 103) belonging to class III or IV by the NYHA classification of HF. The clinical characteristics of the sample are shown in Table 1. Regarding the surgical procedure, 29 (12.6%) patients underwent breast-conserving surgery and 201 (87.4%), valve replacement with prosthesis being used in all these cases biological prosthetic implants. In 90 (39.1%) patients, surgery was associated with AS for other surgical procedures, and in 30.9% (71 cases) associated with coronary artery bypass grafting (CABG) and 3.47% (eight cases) mitral valve replacement. The mean cardiopulmonary bypass time was 84.1 ± 30.1 minutes and myocardial ischemia, 62.8 ± 22.1 minutes. At median follow-up of 4.51 years (0 - 9.55 years), overall survival of the study population (n = 230) was 57.4%, with mean annual mortality of 9.44%. Of the 98 (42.6%) recorded deaths, 48 (34.3%) occurred in the group undergoing surgery for isolated AS and 50 (55.6%) in group associated with another cardiac procedure (OR 1.686 95% 0.827 - 3.436, P = 0.150). In the subgroup of patients who underwent CABG, overall mortality was 54.9% (n = 39). Figure 1 shows the survival curve adjusted for the variables found to be predictors of mortality in multivariate Cox regression and Figure 2 shows the actuarial survival curves of KaplanMeier method with the number of patients at risk each year of follow-up.

Of the total of patients, 13.9% (32 cases) died during the postoperative hospital stay, and this rate of 9.3% (n = 13) in patients undergoing isolated aortic valve surgery and 21.1% (n = 19) when another procedure was associated, a difference that was statistically significant (OR 2.23 95% CI 1.16 to 4.29, P = 0.023). Risk factors for hospital mortality were low cardiac output (OR 10.1 95% CI 5.02 to 20.3, P <0.001), use of intra-aortic balloon (OR 6.6 95% CI 3.83 11.4, P <0.001), sepsis (OR 6.77 95% CI 1.66 to 9.48, P <0.001) and postoperative renal dysfunction (OR 6.21 95% CI 3.47 to 11, 1, P <0.001). The other factors analyzed were not significant in multivariate analysis. Mortality after discharge was 28.7% (n = 66), with 35 deaths (25%) in the AS surgery group alone and 31 (34.4%) among patients with other associated cardiac procedure (OR 1.970 95% CI 0.831 to 4.672, P = 0.124). Of these deaths, 34 (51.51%) were due to cardiovascular causes, with 13 of them in AS surgery group alone and 21 in the group associated with another procedure (OR 3.146 95% CI 1.237 to 8.002, P = 0.016). Figure 3 shows the curve of multivariate Cox regression of cardiovascular mortality after adjusted hospital discharge. We found six (2.6%) cases of IE, 2 (1.4%) patients in the AS surgery group alone and four (4.4%) in combination with another cardiac surgery, eight (3.5%) cases of systemic thromboembolism, four cases per group (2.9% vs. 4.4%). In addition, six (2.6%) patients required reoperation for valve replacement, five (3.6%) in AS surgery group alone and only one (1.1%) in group associated with other cardiac surgery. Figure 4 shows the curve of multivariate Cox regression survival free of adjusted valvular complications.

Fig. 1 - Mortality, according to the time period studied. AS = aortic stenosis

Fig. 2 - Kaplan-Meier actuarial survival, according to the time period studied. AS = aortic stenosis

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DISCUSSION

Fig. 3 - Mortality from cardiovascular causes after hospital discharge, according to the time period studied. AS = aortic stenosis

Fig. 4 - Complication-free survival valve in accordance with the time period studied. AS = aortic stenosis

Among the 66 deaths after hospital discharge, the main causes were septic shock (8, 12.12%) and 5 (7.57%) of them triggered by cardiovascular causes, heart failure decompensation (8, 12.12%), cancer (8, 12.12%), stroke (7, 10.60%) and acute coronary syndrome (5, 5.57%). The predictors of mortality in Cox multivariate analysis were: ischemic time exceeding 90 min (OR 1.99 95% CI 1.06 to 3.74), left ventricular ejection fraction of less than 60% (OR 1.76 95% CI 1.10 to 2.81) and previous stroke (OR 2.43 95% CI 1.18 to 5.30). Since the predictors of mortality after hospital discharge were: left ventricular ejection fraction of less than 60% (OR 1.93 95% CI 1.11 to 3.34) and previous stroke. For the occurrence of valvular complications, associated serious mitral lesion was the only associated significant predictor (OR 3.768 95% CI 1.268 to 11.194).

Whereas the data on in-hospital mortality of patients over 75 years undergoing surgery for AS have been discussed in detail in a previous article published by our group in 2010, this study we will address the discussion of data on mortality and surgical complications correction of EA in the medium term [10]. We note only that, currently, the hospital mortality of isolated aortic valve replacement in elderly people varies between 2 and 10% range that covers the 9.4% rate found in our study [11-13]. Thus, this paper describes the survival rates after hospital discharge up to 4.51 years mean follow up of a consecutive series of 230 patients aged over 75 years undergoing surgery for EA alone or associated with other cardiac surgery , from January 2002 to December 2007, observing the overall mortality rate of 42.6%, with median survival of 57.4% in 4.51 years mean follow-up and a mean annual mortality of 9.44% , similar to that found in the general population in this age group (8.21% deaths / year), according to data from DATASUS [4]. Once the AS is a prevalent condition among older people, increasing the life expectancy of the population has led to increased need for surgical intervention on the aortic valve in this age group, still considered the gold standard for the management of symptomatic patients. It is known that the severity of the obstruction of the ventricular output gradually increases in 10-15 years, there is, thus, a long latency period during which the severity of the stenosis is only mild to moderate and survival is similar to the population generally in the same age [6]. However, since symptoms, even mild, is present, survival decreases dramatically, with an interval between the onset of symptoms and death of approximately 2 years in patients with heart failure, those with syncope 3 years and 5 years in those with angina [ 6]. The possibility of clinical treatment, a review article published in 2010 makes an interesting comparison between the risks of surgery and the dangers of clinical observation in asymptomatic patients with AS. The authors suggest that in patients with severe stenosis and very high risk factors, is increasingly accepted strategy not to delay surgical treatment, usually because the myocardial damage could be irreversible, symptoms may develop rapidly without the correct perception and the patient’s risk of sudden death would increase sharply. They concluded by saying that the conduct must be individualized in these patients: in one extreme, for low-risk patients, the management is conservative, expectant, on the other extreme, for high-risk patients, the procedure is surgical, with aortic valve replacement [14]. In symptomatic patients, the results are even stronger. A cohort study with a population above 80 years compared 271


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patients referred for aortic valve replacement and who agreed with the proposed treatment (group A), patients who require aortic valve replacement that did not agree to undergo surgery (group B) and patients who were unable to undergo surgical treatment and were managed conservatively (group C). The results showed that in group A, the 15 operated patients were alive after 3.6 Âą 1.4 years of follow-up, while groups B and C had a mortality of 74% (24) and 76% (62) during follow-up, respectively. Among patients able to perform the surgery, with similar operative risks (Groups A and B), refusal to undergo surgery has increased by more than 12 times the mortality risk (OR 12.61, P = 0.001) [15]. Analyzing the results of surgery relating to the elderly, the work of Bakaeen et al. [7], developed in patients above 80 years undergoing aortic valve replacement, demonstrates that this group has a higher postoperative morbidity when compared to patients under the age of 80 years (21.1% vs. 15.5 %, P <0.03), however, the late postoperative mortality is similar in both groups (5.2% vs. 3.3%, P = 0.19). Likewise, Mihaljevic et al. [8] showed that, two years after aortic valve replacement, elderly patients have survival similar to that of the general population, matched for age, race and gender (85% survival at 2 years and 65% at 5 years for group of patients over 80 years). When comparing our results with one of the greatest records ever published by AS, the registry of New York, published in 2009 by Hannan et al. [9], which gathered 6,369 patients, we realize that our median survival of 30 months of 78.80% in patients undergoing valve replacement alone was slightly lower than that found in this study in patients above 75 years (86.2 %), a rate equivalent to other published studies [16-19]. The data from the national literature, to analyze the long term evolution (up to 12 years of follow-up) of 287 patients undergoing isolated aortic valve replacement for bovine pericardial bioprosthesis in the period 1992 to 2003, Braile et al. [20] obtained an overall survival of 94.7 Âą 1.7% in patients younger than 70 years (n = 252) and 58.1 Âą 17.2% in patients older than 70 years (n = 35) ( RC 0.20, 95% CI 0.01 to 0.29, P = 0.0005). In our series, up to 9.55 years of follow-up, we observed 66 (28.7%) deaths occurred after hospital discharge, which indicates that the procedure can be performed with reasonable mortality. The association of other surgical procedure resulted in an increase in the mortality rate to 34.4%, difference, although clinically relevant when compared to the group that underwent isolated aortic valve replacement (25.0%) was not statistically significant (P = 0.124). Among the surgical procedures associated with aortic valve surgery, the one which was present in most cases was the CABG, with 61 cases (26.51% of procedures), of

which 12 (19.67%) died in-hospital and 21 (34.4%) after hospital discharge. A significant influence on the increased mortality related to aortic valve replacement when it is associated with CABG had already been reported by Oliveira et al. [21], which demonstrated that the presence of critical coronary artery disease in at least two arteries, significantly influences mortality rates. We emphasize that cardiovascular causes accounted for 51.51% (n = 34) of 66 deaths occurred after hospital discharge, with 38.23% of those in the AS surgery group alone and 61.76% in the group associated with another cardiac procedure (OR 3.146 95% CI 1.237 to 8.002, P = 0.016). Thus, we can observe that, although the association with another cardiac procedure has not significantly increased rates of late mortality, increased, but, significantly, the rate of deaths from cardiovascular causes, the most reliable indicator of its impact. This increase probably denotes a more severe cases, as well as the frequent association between AS and coronary artery disease [10]. In our series, the prognosis of surgery for AS was much aggravated by the presence of surgical factors (ischemia times greater than 90 min), and clinical trials of patients (EF less than 60% and a history of prior stroke), but mainly by association with coronary artery disease that required CABG. Despite the significant increase in survival of patients with AS with surgical indication found in our study, it is estimated that one third of cases of severe symptoms associated with degenerative is not operated at high surgical risk [22]. Aiming precisely or very elderly patients with high surgical risk, there has been the alternative of percutaneous aortic bioprosthesis method feasible, safe and highly effective in this subgroup of patients [23-27]. Although not serve as a comparison because it is a sample of cases selected by the severity and difficult decision for surgery was preferred state in which the percutaneous implantation, it is worth mentioning that in our institution over the past two years, 20 patients with high surgical risk aged between 62 and 99 years and high EuroSCORE (8-92%) underwent percutaneous aortic valve implantation. Throughout the following, we verified the occurrence of a perioperative death, sudden death and death from noncardiac causes, totaling 15% of the sample. The remaining patients showed improvement in functional class, significant immediate decrease in the gradients between the left ventricle and the aorta and increase in valve area [28].

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Limitations This report is retrospective and describes a series of cases operated in a single referral center for cardiovascular surgery, and its results can not be extrapolated to other centers. However, it should be noted that there was no pre-


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selection of patients, surgery was indicated when the clinical situation and in accordance with the attending physician. In addition, we search for patients in the Death Records Services, which helped to significantly reduce our losses, increasing, however, our rates of MACE. The experience reported here refers to a period prior to the availability of percutaneous implantation of aortic prostheses in our midst. Therefore, some high-risk surgical patients underwent surgery as the only treatment option at the moment, may have contributed to an increase in mortality observed.

4. Instituto Brasileiro de Geografia e Estatística IBGE [Internet]. Censo demográfico. Perfil dos idosos responsáveis pelos domicílios no Brasil. Disponível em: http://www.ibge.gov.br/ home/estatistica/populacao/ Acesso em: 4/11/2010

CONCLUSIONS Although the immediate surgical risk of elderly is high, the high mortality rates for the non-symptomatic treatment of severe AS and acceptable survival rates for the surgical treatment in patients over 75 years, similar to the general population in this age group, consent to that intervention. The medium-term prognosis is worsened by the presence of comorbidities and surgical and clinical factors such as low left ventricular EF, longer duration of surgery and prior stroke, but above all, by association with coronary artery disease. These data should be taken into account in deciding the indications for intervention in elderly patients with AS.

5. Frank S, Johnson A, Ross J Jr. Natural history of valvular aortic stenosis. Br Heart J. 1973;35(1):41-6. 6. Braunwald E, Zipes DP, Libby P. Braunwald’s heart disease: a textbook of cardiovascular medicine. 9ª ed. São Paulo:Roca;2003. 7. Bakaeen FG, Chu D, Huh J, Carabello BA. Is an age of 80 years or greater an important predictor of short-term outcomes of isolated aortic valve replacement in veterans? Ann Thorac Surg. 2010;90(3):769-74. 8. Mihaljevic T, Nowicki ER, Rajeswaran J, Blackstone EH, Lagazzi L, Thomas J, et al. Survival after valve replacement for aortic stenosis: implications for decision making. J Thorac Cardiovasc Surg. 2008;135(6):1270-8. 9. Hannan EL, Samadashvili Z, Lahey SJ, Smith CR, Culliford AT, Higgins RS, et al. Aortic valve replacement for patients with severe aortic stenosis: risk factors and their impact on 30-month mortality. Ann Thorac Surg. 2009;87(6):1741-9. 10. Valle FH, Costa AR, Pereira EMC, Santos EZ, Pivatto FJ, Bender LP, et al. Morbimortalidade em pacientes acima de 75 anos submetidos à cirurgia por estenose valvar aórtica. Arq Bras Cardiol. 2010;94(6):720-5. 11. Akins CW, Daggett WM, Vlahakes GJ, Hilgenberg AD, Torchiana DF, Madsen JC, et al. Cardiac operations in patients 80 years old and older. Ann Thorac Surg. 1997;64(3):606-14. 12. Filsoufi F, Rahmanian PB, Castillo JG, Chikwe J, Silvay G, Adams DH. Excellent early and late outcomes of aortic valve replacement in people aged 80 and older. J Am Geriatr Soc. 2008;56(2):255-61. 13. Melby SJ, Zierer A, Kaiser SP, Guthrie TJ, Keune JD, Schuessler RB, et al. Aortic valve replacement in octogenarians: risk factors for early and late mortality. Ann Thorac Surg. 2007;83(5):1651-6.

REFERENCES 1. U.S. Department of Commerce. Bureau of the census. Statistical Abstract of the United States: 1991. 111th ed. Washington: U.S. Department of Commerce; 991. 2. Nkomo VT, Gardin JM, Skelton TN, Gottidiener JS, Scott CG, Enriquez-Sarano M. Burden of valvular heart diseases: a population-based study. Lancet. 2006;368(9540):1005-11. 3. Di Eusanio M, Fortuna D, De Palma R, Dell’Amore A, Lamarra M, Contini GA, et al. Aortic valve replacement: results and predictors of mortality from a contemporary series of 2256 patients. J Thorac Cardiovasc Surg. 2011; 141(4):940-7.

14. Katz M, Tarasoutchi F, Grinberg M. Estenose aórtica grave em pacientes assintomáticos: o dilema do tratamento clínico versus cirúrgico. Arq Bras Cardiol. 2010;95(4):541-6. 15. Kojodjojo P, Gohil N, Barker D, Youssefi P, Salukhe TV, Choong A, et al. Outcomes of elderly patients aged 80 and over with symptomatic, severe aortic stenosis: impact of patient’s choice of refusing aortic valve replacement on survival. QJM. 2008;101(7):567-73. 16. Chiappini B, Camurri N, Loforte A, Di Marco L, Di Bartolomeo R, Marinelli G. Outcome after aortic valve replacement in octogenarians. Ann Thorac Surg. 2004;78(1):85-9.

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17. Elayda MA, Hall RJ, Reul RM, Alonzo DM, Gillette N, Reul GJ Jr, et al. Aortic valve replacement in patients 80 years and older. Operative risks and long-term results. Circulation. 1993;88(5 Pt 2):II11-6.

aortic valve prosthesis for calcific aortic stenosis: first human case description. Circulation. 2002;106(24):3006-8.

18. Straumann E, Kiowski W, Langer I, Grädel E, Stulz P, Burckhardt D, et al. Aortic valve replacement in elderly patients with aortic stenosis. Br Heart J. 1994;71(5)449-53. 19. Tseng EE, Lee CA, Cameron DE, Stuart RS, Greene PS, Sussman MS, et al. Aortic valve replacement in the elderly. Risk factors and long-term results. Ann Surg. 1997;225(6):793-802. 20. Braile DM, Leal JC, Godoy MF, Braile MCV, Paula Neto A. Substituição valvar aórtica por bioprótese de pericárdio bovino: 12 anos de experiência. Rev Bras Cir Cardiovasc. 2003;18(3):217-20. 21. Oliveira Júnior JL, Fiorelli AI, Santos RH, Pomerantzeff PA, Dallan LA, Stolf NA. Does the coronary disease increase the hospital mortality in patients with aortic stenosis undergoing valve replacement? Rev Bras Cir Cardiovasc. 2009;24(4):453-62. 22. Iung B, Baron G, Butchart EG, Delahaye F, Gohlke-Bärwolf C, Levang OW, et al. A prospective survey of patients with valvular heart disease in Europe: The Euro Heart Survey on Valvular Heart Disease. Eur Heart J. 2003;24(13):1231-43. 23. Cribier A, Eltchaninoff H, Bash A, Borenstein N, Tron C, Bauer F, et al. Percutaneous transcatheter implantation of an

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24. Piazza N, Lange R, Bleiziffer S, Grube E, Gerckens U, Windecker S, et al. Predictors of 30-day mortality after transcatheter aortic valve implantation: results from the expanded evaluation registry with the 3rd generation CoreValve revalving system. Am J Cardiol. 2009;104(6):47D-8D. 25. Gaia DF, Palma JH, Ferreira CBND, Souza JAM, Gimenes MV, Macedo MT, et al. Implante transcateter de valva aórtica: resultados atuais do desenvolvimento e implante de um nova prótese brasileira. Rev Bras Cir Cardiovasc. 2011;26(3):33847. 26. Gaia DF, Palma JH, Ferreira CBND, Souza JAM, Agreli G, Guilhen JCS, et al. Implante transapical de valva aórtica: resultados de uma nova prótese brasileira. Rev Bras Cir Cardiovasc. 2010;25(3):293-302. 27. Gaia DF, Palma JH, Souza JAM, Guilhen JCS, Telis A, Fischer CH, et al. Implante transapical de endoprótese valvada balãoexpansível em posição aórtica sem circulação extracorpórea. Rev Bras Cir Cardiovasc. 2009;24(2):233-8. 28. Bernardi GLM, Sarmento Leite R, Prates PRL, Quadros AS, Salgado Filho PA, Giusti I, et al. Implante valvular aórtico percutâneo (IVAP): dois anos da experiência inicial. Análise de seguimento de curto, médio e longo prazo. Rev Bras Cardiol Invas. 2011;19(2):40.


ORIGINAL ARTICLE

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Fetal cardiac output and ejection fraction by spatio-temporal image correlation (STIC): comparison between male and female fetuses Débito cardíaco e fração de ejeção fetal por meio do spatio-temporal image correlation (STIC): comparação entre fetos masculinos e femininos

Christiane Simioni1, Edward Araujo Júnior2, Wellington P. Martins3, Liliam Cristine Rolo4, Luciane Alves da Rocha5, Luciano Marcondes Machado Nardozza6, Antonio Fernandes Moron7

DOI: 10.5935/1678-9741.20120058

RBCCV 44205-1381

Abstract Objective: To compare the cardiac output (CO) and ejection fraction (EF) of the heart of male and female fetuses obtained by 3D-ultrasonography using spatio-temporal image correlation (STIC). Methods: We conducted a cross-sectional study with 216 normal fetuses, between 20 and 34 weeks of gestation, 108 male and 108 female. Ventricular volumes at the end of systole and diastole were obtained by STIC, and the volumetric assessments performed by the virtual organ computer-aided analysis (VOCAL) rotated 30°. To calculate the DC used the formula: DC = stroke volume / fetal heart rate, while for the FE used the formula: EF = stroke volume / end-diastolic volume. The DC (combined male and female) and EF (male and female) were compared using the unpaired t test and ANCOVA. Scatter plots were created with the percentiles 5, 50 and 95. Results: The average of DC combined, DC left, DC right, FE right and FE left, male and female were 240.07 mL/min, 122.67 mL/min, 123.40 mL/min, 72.84%, 67.22%, 270.56 mL/ min, 139.22 mL/min, 131.34 mL/min, 70.73% and 64.76%

respectively, without statistical difference (P> 0.05). Conclusions: The fetal CO and EF obtained by 3Dultrasonography (STIC) showed no significant difference in relation to gender.

1. MD, Master of Science, Department of Obstetrics, Federal University of São Paulo, São Paulo, Brazil. 2. PhD, Associate Professor, Department of Obstetrics, Federal University of São Paulo, Sao Paulo, Brazil. 3. PhD, Attending Physician, Department of Gynecology and Obstetrics, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil. 4. PhD, Master of Science, Department of Obstetrics, Federal University of São Paulo, São Paulo, Brazil. 5. MD, Postgraduate student, Department of Obstetrics, Federal University of São Paulo, São Paulo, Brazil. 6. PhD, Associate Professor, Department of Obstetrics, Federal University of São Paulo, São Paulo, Brazil. 7. PhD, Professor, Department of Obstetrics, Federal University of São Paulo, São Paulo, Brazil.

Work performed at the Fetal Cardiology, Department of Obstetrics, Federal University of São Paulo (UNIFESP), São Paulo, Brazil.

Descriptors: Fetal heart. Cardiac output. Cardiac volume. Echocardiography, three-dimensional. Heart rate.

Resumo Objetivo: Comparar do débito cardíaco (DC) e a fração de ejeção (FE) do coração de fetos masculinos e femininos obtidos por meio da ultrassonografia tridimensional, utilizando o spatio-temporal image correlation (STIC). Métodos: Realizou-se um estudo de corte transversal com 216 fetos normais, entre 20 a 34 semanas de gestação, sendo 108 masculinos e 108 femininos. Os volumes ventriculares no final da sístole e diástole foram obtidos por meio do STIC, sendo as avaliações volumétricas realizadas pelo virtual organ computer-aided analysis (VOCAL) com rotação de 30º. Para o cálculo do DC utilizou-se a fórmula: DC= volume

Corrrespondence address Edward Araujo Júnior. Rua Carlos Weber, 956 – apto. 113 – Visage Alto da Lapa – São Paulo, SP, Brazil – Zip code 05303-000 E-mail: araujojred@terra.com.br

Article received on March 1st , 2012 Article accepted on May 7th, 2012

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Abbreviations, acronyms & symbols CRL CO CHD SD EF EFW FHR EF GA ROI STIC UNIFESP US 2D US 3D VOCAL SV

Crown-rump length Cardiac output Congenital heart disease Standard deviation Ejection fraction Estimation of fetal weight Fetal heart rate Ejection fraction Gestational age in weeks Region of Interest Spatio-temporal image correlation Federal University of Sao Paulo Bi-dimensional ultrasonound Three-dimensional ultrasound Virtual organ computer-aided analysis Systolic volume

INTRODUCTION Congenital heart disease (CHD) accounts for significant portion of the rate of perinatal morbidity and mortality by both anatomical and functional cardiac defects. The DCC is the most common major malformations at birth [1,2], with a prevalence of 0.6 to 5% of live births [3]. Despite great efforts and technological advancement of two-dimensional echocardiography in the past two decades, the accuracy in detecting congenital heart disease in pre-natal is between 31% to 96% [4,5]. Despite the two-dimensional ultrasound (2D U.S.) is used for the study of cardiac anatomy with good accuracy for the analysis of fetal cardiac function by means of this diagnostic modality is still limited [6]. The analysis of the stroke volume (SV) and ejection fraction (EF) uses the formula Teichholz, which can be applied to wells of any size, assuming the ventricle has an elliptical shape, or using only a constant (X x Y x Z x 0.52) [7]. The Simpson’s method is also employed for this purpose, but even more complex by dividing the ventricle in multi-cylinder, calculating the EP to each medium and maintaining the total of the fractions isolated [8]. The three-dimensional ultrasonography (3D U.S.) allows a more accurate volumetric evaluation that 2D ultrasound, especially for objects of irregular shapes, it allows the design of its outer surface [9], which may be of potential use for evaluation of fetal cardiac function. The Spatio-Temporal 276

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sistólico/frequência cardíaca fetal, enquanto que para a FE utilizou-se a fórmula: FE= volume sistólico/volume diastólico final. O DC (combinado, feminino e masculino) e a FE (masculina e feminina) foram comparadas utilizandose o teste t não pareado e ANCOVA. Foram criados gráficos de dispersão com os percentis 5, 50 e 95. Resultados: A média do DC combinado, DC direito, DC esquerdo, FE direita e FE esquerda, para feminino e masculino, foram 240,07 mL/min; 122,67 mL/min; 123,40 mL/min; 72,84%; 67,22%; 270,56 mL/min; 139,22 mL/min; 131,34 mL/min; 70,73% e 64,76%, respectivamente; sem diferença estatística (P> 0,05). Conclusões: O DC e a FE fetal obtidos por meio da ultrassonografia tridimensional (STIC) não apresentaram diferença significativa em relação ao gênero. Descritores: Coração fetal. Débito cardíaco. Ecocardiografia tridimensional. Frequência cardíaca.

Image Correlation (STIC) is a software that allows a volumetric acquisition of the fetal heart with its vascular connections, and the images can be evaluated both on the multiplanar mode and surface (rendered). The images may be evaluated both a static and moving (4D) by means of a Cineloop sequence that simulates a complete cardiac cycle. The advantages of STIC to evaluate fetal heart are less dependent on operator’s experience in obtaining diagnostic plans, shorter examination carried out with analysis of volumes in the absence of the patient, ability to assess structures by rendering mode to study their morphology and function [1012]. With respect to cardiac evaluation at STIC, first study was performed by Messing et al. [13], who evaluated the volume of the ventricular chambers in both systole and diastole in 100 fetuses using methods Virtual Organ Computer-aided Analysis (VOCAL) associated with the inversion mode. Later, other authors also evaluated fetal cardiac function and Molina et al. [14] who used the STIC associated only with VOCAL, Uittenbogaard et al. [15] who used the STIC and 3D slice method and, more recently, Simioni et al. [16] and Hamill et al. [17], using only the VOCAL associated with STIC. However, no studies comparing cardiac function by means of 3D U.S. with STIC in relation to gender. It is known that in adults, by means of 3D echocardiography, women have a higher volume / ventricular mass than men of similar age [18]. The objective of this study was to compare cardiac


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output (CO) and EF heart male and female fetuses by 3D ultrasound using STIC and VOCAL software in order to try to determine if cardiac function is already dependent on gender antenatal period.

observer, by means of 2D U.S., carried out the measurements of biparietal diameter, abdominal circumference and femur length to determine the estimated fetal weight [21]. The determination of the genus fetal was performed using the 2D U.S. [22]. The fetal heart rate (FHR) was determined by pulsed Doppler ultrasonography of the mitral valve. For the acquisition of the fetal heart volume, initially there was a two-dimensional evaluation in order to obtain an axial level of the four heart chambers. Then, with the fetus asking the home and pregnant breath for a few seconds, there was a 3D scan. Therefore, if the key-activated STIC, so that the region of interest (ROI) encompassing only the heart with their vascular connections. The sweep angle and speed of acquisition was determined by the examiner. The angle ranged from 20° to 25° in the first quarter, and 25° to 30° in the third quarter, while the acquisition time from 10 to 12.5 seconds. After the capture volume, it was found and the quality of that which is considered satisfactory, it was stored in the memory. After standardization of the position of the fetal heart Paladini proposed by [23], a single volume of each fetal heart was stored in the memory. Subsequently, volumes were recorded on compact discs (CDs) and transferred to a personal computer (PC). The analyses were performed offline using the software 4D View version 9.1 (General Electric Healthcare). The axial plane of the multiplanar mode was selected as a reference. In order to evaluate the dynamics of the mitral and tricuspid valves, gradually reduce the speed of cinellop to obtain exact opening and closing of valves. The maximum diameter of the ventricle to the mitral and tricuspid valves determined the closed end of the ventricular diastole, whereas the smaller diameter end determined the ventricular systole. Then the key is activated VOCAL with a rotation angle of 30° (setting six consecutive planes). Thus, the reference point was moved to the center of the ventricle, and the axial plane rotated around the axis “y”, so the cardiac apex is available within 12 hours. It was performed manually six planes defining the left ventricle after which the device provided the reconstructed image with the volume of the ventricular cavity. The same process was repeated for the right ventricle. Finally, there were obtained the volumes of the right and left ventricles, either at the end of systole and in the end of diastole. The stroke volume of each ventricle was determined by the formula: stroke volume = (ventricular volume at end diastole) - (ventricular volume at end systole). The DC each ventricle was determined by the equation: DC = (stroke volume) * (FCF). The combined DC was determined by adding the values obtained for the DC of the right ventricle and left. The EF of each ventricle was determined by the formula: EF = (stroke volume) / (ventricular volume at end diastole). Statistical analysis was performed using the programs Excel 2007 (Microsoft Corp., Redmond, WA, USA), PASW

METHODS We conducted a cross-sectional study, from May 2009 to July 2011, with healthy pregnant women between 20-34 weeks and 6 days. This study was approved by the Ethics Committee in Research of the Federal University of Sao Paulo (UNIFESP) No 0234/09, and the patients who consented to participate voluntarily signed a consent form. Inclusion criteria were: 1) singleton pregnancy with live fetus, 2) gestational age determined by last menstrual period and confirmed by first trimester ultrasound, using as parameter the crown-rump length (CRL), with a difference less than 5 days. Exclusion criteria were: 1) the fetal position with the dorsal anterior (between 11 and 1h), 2) excessive fetal movements, 3) severe attenuation of the sound beam (obesity, abdominal scars), 4) fetal malformation detected on ultrasound, 5) estimated fetal weight below the 10th percentile or above the 90th percentile, according to Hadlock et al. [19], 6) amniotic fluid index below the 5th percentile or above the 95th percentile, according to Moore & Cayle [20], 7) maternal chronic diseases that could interfere with fetal growth (chronic hypertension, diabetes mellitus and collagen) ; 8) cases in which it was not possible to identify the fetal external genitalia. All patients were selected randomly, and these are coming from the Division of Prenatal Physiology, Department of Obstetrics, UNIFESP, or Basic Health Units of the metropolitan region of São Paulo (Brazil). Patients were evaluated only once, no data were obtained postnatally. The following variables were evaluated pregnant women included: age, number of previous pregnancies and deliveries, gestational age, fetal weight, fetal heart rate (FHR), fetal gender, DC right ventricular and left ventricular EF and combined right and left. Age, number of previous pregnancies and deliveries of the pregnant women were obtained by questionnaires. The other variables were evaluated by ultrasonography. The tests were conducted at Centro Paulista de Medicina Fetal (CPMF) and the Division of ThreeDimensional Ultrasound, Department of Obstetrics, UNIFESP, which were accomplished by only two investigators (CS and LLC), both with three years experience in 3D ultrasound in Obstetrics. All examinations were performed on branded handsets Voluson 730 Expert (General Electric Healthcare, Zipf, Austria) using a multifrequency convex volumetric transducer (RAB 4-8L). Initially, the

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(version 18.0, SPSS Inc., Chicago, IL, USA) and GraphPad (version 5.0, GraphPad Software, San Diego, CA, USA). The normal distribution was assessed using the Kolmogorov-Smirnov test. We compared maternal age, gestational age, fetal weight and FCF between the fetus

pregnancies with female and male by means of the Student’s t-test. Number of pregnancies and parity between groups was compared using the Mann-Whitney test. The DC (right, left and combined) and EF (right and left) were compared between groups by unpaired t-test and also by ANCOVA,

Table 1. Comparison of maternal age, number of pregnancies, parity, fetal weight and fetal heart rate between male and female fetuses. Age (years) Number of pregnancies Parity Gestational age (weeks) EFW (g) Fetal heart rate (bpm)

Female Mean SD 29.20 5.30 1.55 0.83 0.43 0.70 26.54 4.40 1058.56 623.61 141.19 9.69

Male Mean 29.83 1.64 0.51 27.34 1195.21 140.08

SD 6.23 0.96 0.75 4.66 685.46 9.37

P 0.43 0.49 0.29 0.19 0.13 0.39

EFW = estimated fetal weight, SD = standard deviation, P - value determined by unpaired t-test for age, gestational age, fetal heart rate and EFW, P-value determined by Mann-Whitney test for number of pregnancies and parity

Table 2. Comparison of fetal cardiac parameters evaluated between male and female fetuses. Cardiac output - right (mL/min) Cardiac output - left (mL/min) Cardiac output - combined (mL/min) Ejection fraction - right (%) Ejection fraction – left (%)

Female Mean SD 123.40 96.39 122.67 86.20 246.07 174.15 67.22 11.34 72.84 10.95

Male Mean 131.34 139.22 270.56 64.76 70.73

SD 104.36 108.82 200.75 11.55 10.94

P1 0.56 0.21 0.34 0.11 0.16

P2 0.46 0.70 0.84 0.20 0.28

P3 0.27 0.91 0.58 0.22 0.32

P4 0.30 0.79 0.67 0.20 0.34

Cardiac output combined = (Cardiac Output - left) + (cardiac output - right), SD = standard deviation, P¹ = P-value determined by paired t test, P² = P-value evaluated by ANCOVA using gestational age as a covariate; P³ = P value assessed by ANCOVA using the estimated fetal weight as a covariate, Pt = P-value evaluated by ANCOVA using both gestational age and estimated fetal weight as covariates

Table 3. Percentiles 5.50 and 95 for cardiac output - right, left and combined, considering both male and female fetuses. GA 26 27 28 29 30 31 32 33 34 35

Right ventricle (mL/min) Percentile 5 50 95 35.44 101.65 167.86 41.77 118.25 194.72 48.48 135.78 223.09 55.55 154.26 252.96 173.67 284.35 62.99 70.80 194.03 317.25 78.98 215.32 351.66 87.53 237.56 387.59 260.73 425.02 96.44 105.72 284.84 463.96

Left ventricle (mL/min) Percentile 5 50 95 37.41 101.40 165.39 44.27 116.59 188.90 51.53 132.61 213.68 59.19 149.47 239.74 167.16 267.06 67.26 75.72 185.69 295.66 84.58 205.05 325.52 93.85 225.26 356.66 103.52 246.29 389.07 113.59 268.17 422.74

Combined (mL/min) Percentile 5 50 95 99.83 204.96 310.09 118.32 237.08 355.84 137.90 271.00 404.11 158.56 306.72 454.88 180.30 344.23 508.15 203.13 383.53 563.93 227.04 424.63 622.22 252.04 467.53 683.01 278.13 512.22 746.31 305.30 558.71 812.12

GA = gestational age in weeks; combined cardiac output = cardiac output of right ventricle + left ventricle cardiac output; percentiles estimated standard deviation, as suggested by Altman & Chitty [24]

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using gestational age and / or estimated fetal weight as covariates. Since we did not notice a difference in the evaluated parameters between fetuses were male and female, were determined curves of normal (5th percentile, 50 and 95) by the mean and standard deviation for the estimated gestational age [24], using data from all fetuses.

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RESULTS We initially evaluated 290 pregnant women; however, 34 were excluded due to unfavorable fetal position, 5 per estimated fetal weight below the 10th percentile for gestational age and 35 for failing to identify fetal sex. So for the final statistical

Table 4. Percentiles 5, 50 and 95 for the ejection fraction - right and left, considering both male and female fetuses.

GA 26 27 28 29 30 31 32 33 34 35

Right ventricle Percentile 5 50 54.15 69.80 53.76 69.33 53.18 68.62 52.42 67.69 51.48 66.51 50.36 65.11 49.05 63.47 47.56 61.59 45.88 59.49 57.15 44.02

(%) 95 85.45 84.90 84.06 82.95 81.54 79.86 77.89 75.63 73.09 70.27

Left ventricle (%) Percentile 5 50 95 61.00 75.98 165.39 188.90 60.19 75.53 59.15 74.84 213.68 57.87 73.90 239.74 267.06 56.36 72.71 54.61 71.27 295.66 325.52 52.63 69.58 50.41 67.64 356.66 47.97 65.45 389.07 422.74 45.28 63.02

GA = gestational age in weeks; percentiles estimated standard deviation as suggested by Altman & Chitty [24]

Fig. 1 - Curves of reference - 5, 50 and 95 percentile - for cardiac output: A) Right ventricle; B) Left ventricle, C) = cardiac output combined (right ventricle) + (left ventricle). The percentiles were evaluated as suggested by Altman & Chitty [24], using data from both fetuses, male and female

Fig. 2 - Curves of reference - 5, 50 and 95 percentile - for ejection fraction: A) Right ventricle; B) Left ventricle. The percentiles were evaluated as suggested by Altman & Chitty [24], using data from both fetuses, male and female.

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analysis we included 216 fetuses, with 108 of each sex. There was no significant difference between the fetuses of pregnant women with male and female regarding maternal age, number of previous pregnancies and deliveries, gestational age, fetal weight and fetal heart rate (Table 1). No significant differences when comparing the CD and EF between the fetuses were male and female, both the analysis of initial data, even when adjusting for gestational age, estimated fetal weight, or both (Table 2). Thus, the percentiles for the CD and EF were calculated for gestational ages between 26 and 35 weeks, using data both from male fetuses as female (Tables 3 and 4, Figures 1 and 2).

In our study, as we have not identified differences in cardiac function in male and female fetuses, we determined reference values only for both the DC (right, left and combined) and for EF (right and left). We opted for the determination of reference values from 26 weeks, taking into account fetal viability. In relation to the previous study by Molina et al. [14], who evaluated 100 fetuses of both sexes, between 12 and 34 weeks, we observed that their values were overestimated compared to ours. We believe that one possible reason is the inclusion in the endocardium volume calculation, while in this study only the area delimited anechoic (blood) present in the cardiac chambers, the same as in previous studies by our group [16.28] . In comparison with longitudinal study carried out by Uittenbogaard et al. [15] who used the technique 3D slice, we observed that in the range 26 to 30 weeks, our values were also underestimated the likely cause is possibly also the inclusion of the endocardium in the volumetric calculations performed in that study. In a recent study by Hamill et al. [17], who evaluated 180 cardiac volumes by STIC and VOCAL, we found that DC increased with gestational age and did not differ between the right and left ventricles, whereas EF decreased with gestational age and was higher in the left ventricle . These results are in agreement with those obtained in our study, with 216 fetuses of both sexes. This study did not evaluate the reproducibility of the method STIC and VOCAL, because it has been proven in a previous study conducted by our group [16], as well as other studies [14,27,29]. Limitations of this study relate primarily to the capture volume, which requires a fetal position right (back in 6 hours) or semi-ideal (back between 3 and 9), poor fetal movements and apnea in pregnant women, which sometimes makes testing extremely time consuming. Furthermore, the post-processing of images, with calculations of ventricular volumes at the end of systole and diastole, to obtain the CD and EF consumes a long time (10-12 minutes), making their use in clinical practice. Another limitation relates to biotype and the presence of maternal abdominal scars generating acoustic shadows difficult and sometimes impossible to capture a stroke volume to a satisfactory quality. The same limitations have already been described in a previous study carried out by Hamill et al. [29].

DISCUSSION In this study, we evaluated fetal cardiac function by means of 3D U.S., using the softwares STIC and VOCAL. We used the limit range of 20 to 34 weeks, because during this period the visualization of cardiac chambers is easier, providing better heart volume. In addition, below 20 weeks postnatal fetal viability is not possible, making it unnecessary to evaluation of their cardiac function. Used as standards for acquiring volumetric cutting four cardiac chambers, where possible position of the back in 6 hours, a sweep angle ranging from 20 ° to 30 ° according to the gestational age, as long as possible to acquire, in addition to exclusion of cases with back between 11 and 1am, as proposed by Gonçalves et al. [25]. This study aimed to evaluate possible differences in cardiac function according to fetal gender. However, we could not demonstrate significant differences for both the DC and for the FE, both adjusted for gestational age and the estimated fetal weight. In a study using 3D transthoracic echocardiography, the volume / left ventricular mass was significantly higher in women than in men of similar age. Another cause could be the largest pulmonary resistance of women relative to men, as a possible consequence of increased left ventricular EF. A previous study by 2D echocardiography has shown that heart failure with normal EF is often more common in women than in men of similar age [26]. Possibly, external factors acting in the postnatal period may justify the difference in cardiac function in relation to gender, in adults of the same age. In this study, 290 pregnant women were initially evaluated, 34 were excluded due to poor quality of packages corresponding to a rate of 11.7% loss. In a recent study by Schoonderwaldt et al. [27], 84 women were initially evaluated between 20-34 weeks, however, excluded volume 54, corresponding to a rate of 64% loss. This high rate of loss due to low quality of cardiac volumes is due to inclusion of the previous position back as an exclusion criterion and the small number of cases evaluated in comparison to the study conducted by us. 280

CONCLUSION In summary, this is the first study that sought to assess differences in the intrauterine fetal cardiac function in relation to gender by US 3D. The lack of statistical difference observed in the CD and EF of male and female fetuses implies that external factors postnatal are responsible for these


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observed differences in adult life for people of different sex and same age. Further studies evaluating the cardiac function by means of 3D U.S. in childhood and adolescence are necessary to confirm our assumption.

evaluation of the fetal heart. Ultrasound Obstet Gynecol. 2003;22(4):380-7.

REFERENCES 1. Silva MEM, Feuser MR, Silva MP, Uhlig S, Parazzi PLF, Rosa GJ, et al. Cirurgia cardíaca pediátrica: o que esperar da intervenção fisioterapêutica? Rev Bras Cir Cardiovasc. 2011;26(2):264-72. 2. Hoffman JI. Incidence of congenital heart disease: I. Postnatal incidence. Pediatr Cardiol. 1995;16(3):103-13. 3. Grandjean H, Larroque D, Levi S. The performance of routine ultrasonographic screening of pregnancies in the Eurofetus Study. Am J Obstet Gynecol. 1999;181(2):446-54. 4. Strumpflen I, Strumpflen A, Wimmer M, Bernaschek G. Effect of detailed fetal echocardiography as part of routine prenatal ultrasonographic screening on detection of congenital heart disease. Lancet. 1996;348(9031):854-7. 5. Berghella V, Pagotto L, Kaufman M, Huhta JC, Wapner RJ. Accuracy of prenatal diagnosis of congenital heart defects. Fetal Diagn Ther. 2001;16(6):407-12. 6. Esh-Broder E, Ushakov FB, Imbar T, Yagel S. Application of free-hand three-dimensional echocardiography in the evaluation of fetal cardiac ejection fraction: a preliminary study. Ultrasound Obstet Gynecol. 2004;23(6):546-51. 7. Schmidt KG, Silverman NH, Hoffman JI. Determination of ventricular volumes in human fetal hearts by two-dimensional echocardiography. Am J Cardiol. 1995;76(17):1313-16. 8. Meyer-Wittkopf M, Cole A, Cooper SG, Schmidt S, Sholler GF. Three-dimensional quantitative echocardiographic assessment of ventricular volume in healthy human fetuses and in fetuses with congenital heart disease. J Ultrasound Med. 2001;20(4):317-27. 9. Riccabona M, Nelson TR, Pretorius DH. Three-dimensional ultrasound: accuracy of distance and volume measurements. Ultrasound Obstet Gynecol. 1996;7(6):429-34. 10. Gonçalves LF, Lee W, Chaiworapongsa T, Espinoza J, Schoen ML, Falkensammer P, et al. Four-dimensional ultrasonography of the fetal heart with spatiotemporal image correlation. Am J Obstet Gynecol. 2003;189:1792-802. 11. DeVore GR, Falkensammer P, Sklansky MS, Platt LD. Spatiotemporal image correlation (STIC): new technology for

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23. Paladini D. Standardization of on-screen fetal heart orientation prior to storage of spatio-temporal image correlation (STIC) volume datasets. Ultrasound Obstet Gynecol. 2007;29(6):605-11.

27. Schoonderwaldt EM, Groenenberg IA, Hop WC, Wladimiroff JW, Steergers EA. Reproducibility of echocardiography measurements of human fetal left ventricular volumes and ejection fractions using four-dimensional ultrasound with the spatio-temporal image correlation modality. Eur J Obstet Gynecol Reprod Biol. 2012;160(1):22-9.

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ORIGINAL ARTICLE

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Flowmetry of left internal thoracic artery graft to left anterior descending artery: comparison between on-pump and off-pump surgery Fluxometria da artéria torácica interna esquerda na revascularização da artéria descendente anterior com e sem circulação extracorpórea

Filinto Marques de Cerqueira Neto1, Marco Antonio Vieira Guedes2, Leonardo Eugênio Fonseca Soares3, Gustavo Santiago Almeida3, André Raimundo F. Guimarães3, Mauricio Alves Barreto4, Emerson Costa Porto4, Álvaro Rabelo Júnior5

DOI: 10.5935/1678-9741.20120045

RBCCV 44205-1382

Abstract Background: Off-pump coronary bypass grafting (OPCAB) has become a widely used technique. Coronary flowmetry is the most common method employed to assess graft patency, nevertheless, few studies compare flow patterns between ONCAB and OPCAB surgery. The objective of this study was to compare flowmetry data in left internal mammary artery grafts bypasses to the left anterior descendent artery. Methods: From March to September of 2010, thirty-five consecutive, non-randomized patients underwent CABG and were retrospectively evaluated. Ten patients were located on group A (On Pump), and twenty-five on group B (Off Pump). The mean graft flow (MGF), pulsatile index (PI) and diastolic filling (DF) were obtained using Transit Time Flowmetry (TTFM). The Fisher exact test, and Mann Whitney test were used, and a P value of < 0.05 was

considered to indicate statistical significance. Results: There were no deaths, AMI, re-interventions or PTCA in a 30-day period. The number of bypasses performed per patient was 2.3 ± 0.8 in the OPCAB group, and 2.2 ± 0.6 in the ONCAB group, with no significant difference (P=0.10). The median of mean flow was 23 ml/min on group A, and 25 ml/min on group B (P=0.34). Diastolic filling percentage was 56% on group A, and 56.9% on group B (P=0.86). Pulsatile Index was 2.3 on group A, and 2.2 on group B (P=0.82). Conclusions: There was no difference between TTFM values (MF, PI and DF) in patients operated with or without cardiopulmonary bypass.

1. Specialist in Cardiovascular Surgery - BSCVS and MEC, Cardiovascular Surgeon, Salvador, Bahia, Brazil. 2. Doctor of Science from the School of Medicine, University of Sao Paulo, Specialist in Cardiovascular Surgery - BSCVS and MEC, Salvador, Bahia, Brazil. 3. Residency in Cardiovascular Surgery - Bahia Foundation of Cardiology. 4. Specialist in Cardiology by MEC and SBC, Salvador, Bahia, Brazil. 5. President of the Bahia Foundation of Cardiology, Salvador, Bahia, Brazil.

Correspondence address: Filinto Neto Marques de Cerqueira 326 Hortências Street - Pituba - Salvador, Bahia, Brazil Zip code: 41810-010. E-mail: filintomc@hotmail.com

Work performed at Bahia Foundation of Cardiology, Salvador, Bahia, Brazil.

Descriptors: Coronary artery bypass, off-pump. Myocardial revascularization. Coronary artery bypass. Flowmeters. Laser-doppler flowmetry.

Article received on January 9th, 2012 Article accepted on April 7th, 2012

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Abbreviations, Acronyms & Symbols CP LITA C VA EC Cr ADA CAD OPAD DF DF_LADA PDF FBC Ef MGF TTF AMI BMI PI CABG ACT

Coupling percentage Left internal thoracic artery Cerebrovascular Accident Extracorporeal Circulation Creatinine Anterior descending artery Coronary artery disease Obstructive Peripheral Arterial Disease Diastolic filling Percent of diastolic filling of the left anterior descending artery Percentage of diastolic filling Bahia Federation of Cardiology Ejection fraction Median grafts flow Transit-time flowmetry Acute myocardial infarction Body Mass Index Pulsatility index Coronary artery bypass grafting Activated clotting time

Resumo Introdução: A cirurgia de revascularização do miocárdio (RM) sem circulação extracorpórea (CEC) é uma técnica amplamente utilizada. A fluxometria coronariana é a técnica mais usada para avaliação dos enxertos, porém, poucos estudos comparam os dados fluxométricos na RM com e sem CEC. O objetivo deste estudo foi comparar as variáveis

INTRODUCTION Coronary artery bypass graft (CABG) without the use of extracorporeal circulation (EC) has been used in order to reduce complications related to the inflammatory response to EC, but the literature has shown controversial results regarding the superiority of this technique [1-9]. In 2009, ROOBY TRIAL [10] compared the clinical and angiographic outcomes of CABG with and without EC and concluded that only the anastomoses of the left internal thoracic artery (LITA) made in the anterior wall of the heart had similar patency rates after one-year follow-up period, while the saphenous vein grafts to other walls had lower results in off-pump technique. The Transit-time flowmetry (TTF) is the most common technique used for immediate intraoperative assessment of graft patency. The TTF measures the average flow in the 284

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fluxométricas dos enxertos de artéria torácica interna esquerda para a artéria descendente anterior em pacientes submetidos à RM com e sem CEC. Métodos: Entre março e setembro de 2010, foram analisados retrospectivamente 35 pacientes consecutivos, não randomizados, submetidos à RM. Foram alocados 10 pacientes no grupo A (com CEC) e 25 no grupo B (sem CEC). O fluxo médio do enxerto (FME), o índice pulsátil (PI) e a porcentagem de enchimento diastólico (ED) foram obtidos por meio da fluxometria por tempo de trânsito. Foi utilizado o teste exato de Fisher e Mann-Whitney, sendo considerado estatisticamente significante P<0,05. Resultados: Não houve óbito, infarto agudo do miocárdio ou necessidade de angioplastia em 30 dias de pós-operatório. O número médio de anastomoses distais foi 2,3 ± 0,8 por paciente no grupo sem CEC, e de 2,2 ± 0,6 no grupo com CEC (P=0,10). A mediana do fluxo médio do enxerto foi 23 ml/min, no grupo A, e 25 ml/min, no grupo B (P=0,34). A percentagem de enchimento diastólico foi 56%, no grupo A, e 59,5%, no grupo B (P=0,86). O índice pulsátil foi 2,3, no grupo A, e 2,2, no grupo B (P=0,82). Conclusão: Não houve diferença nos parâmetros fluxométricos (FME, ED e PI) encontrados nos pacientes submetidos à revascularização do miocárdio com e sem CEC. Descritores: Ponte de artéria coronária sem circulação extracorpórea. Revascularização miocárdica. Ponte de artéria coronária. Fluxômetros. Fluxometria por laserdoppler.

graft (MGF), and provides a flow curve and derived variables such as the pulsatility index (PI) and the percentage of diastolic filling (DF). This technology allows quantification of the flow regardless of the size and shape of the vessel or use of the angle sensor [11-13]. However, there are few studies comparing the fluxometric data in the literature when performing on-pump or off-pump CABG. The objective of this study was to compare the fluxometric variables of internal thoracic artery grafts to left anterior descending artery (LADA) in patients undergoing CABG with and without EC. METHODS This study was conducted at Bahia Foundation of Cardiology (FBC) by only one surgical team. After the study was approved by the Ethics Committee of the FBC, between


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March and September 2010, 35 consecutive patients were retrospectively analyzed, not randomized, patients with coronary artery disease who underwent CABG. We excluded patients undergoing previous heart surgery that required associated intraoperative procedures, emergency surgery or those who required use of intra-aortic balloon.

The patients were divided into two groups (Group A and Group B), according to the CABG. In group A, there were ten patients undergoing CABG with EC and in group B, 25 patients undergoing CABG without EC. The demographic and clinical groups are detailed in Table 1.

Table 1. Demographic and clinical pre-operative parameters off-pump operation n = 25 65.7 ± 9.2 Age 19 (76%) Male gender BMI 27.1 ± 3.01 8 (32%) Diabetes mellitus 19 (76%) Arterial Hypertension 10 (40%) Dyslipidemia 5 (20%) Previous BMI Ef < 50% 3 (12%) Cerum Creatinine > 2 mmol/L 1 (4%) 16 (64%) Triarterial CAD 3 (12%) Previous CVA OPAD 4 (16%) Variables

on-pump operation n = 10 66.6 ± 4.3 6 (60%) 27.9 ± 4.17 3 (30%) 9 (90%) 5 (50%) 4 (40%) 1 (10%) 0 7 (70%) 0 0

P 0.63 0.42 0.58 1.00 0.64 0.71 0.39 1.00 1.00 1.00 0.54 0.30

EC: Extracorporeal Circulation, BMI: body mass index, AMI: acute myocardial infarction, EF: ejection fraction, Cr: creatinine, CAD: coronary artery disease, CVA: Cerebrovascular Accident, OPAD: Obstructive peripheral arterial disease

Fig. 1 - Fluxometric analysis of the ADA. The red line corresponds to the grafts flow, expressed in ml / min, in the upper left corner of the figure. The flow vs. time curve is divided into the systolic phase (pink) and the diastolic phase (blue). PI: pulsatility index; DF: diastolic filling; CP coupling percentage

Surgical Technique All patients underwent CABG through median sternotomy. The LITA was dissected with preservation of vascular pedicle and wrapped with gauze soaked in papaverine. In the group undergoing CABG with EC, patients were heparinized with 400 IU / kg to maintain an ACT (activated clotting time) > 480 seconds. The installation of EC was performed in standard mode. The patients were operated on with hypothermia at 32°C, and anoxic arrest was performed by infusion of cold blood cardioplegia which was injected into the aortic root. The anastomosis of the LITA in the ADA was the last to be performed. For other coronary branches, when indicated, saphenous vein grafts were prepared. The proximal anastomoses were performed with side clamping of the aorta. Finally, the heparin was reversed with the infusion of 1mg protamine sulfate per 100 IU heparin. In the group undergoing off-pump CABG, patients were heparinized with 300 IU / kg to maintain an ACT> 400s. Exposure of coronary arteries was obtained with use of the technique described by Lee et al. [14]. The segmental stabilization myocardium was obtained with Octopus 3 tissue stabilizer (Medtronic Inc., Minneapolis, MN). The visualization was facilitated by the use of CO2 jet. Coronary flow was maintained through the use of intracoronary shunts (Medtronic Inc., Minneapolis, MN, USA), compatible with the size of the vessel diameter. The anastomosis of the LITA in ADA was always the first one to be performed. The proximal anastomoses, when used saphenous vein grafts to other coronary branches, were performed by aortic-side clamping. In the end, heparin was reversed with the infusion of 1mg protamine sulfate per 100 IU of heparin. Transit-time flowmetry (TTF) The use of this technique was described by D’FMTT AOI et al. [13]. Transducers from Medi Stim brand were used (Oslo, Norway) and sterilized with ethylene oxide. A segment measuring approximately 2 cm of the LITA was skeletonized in its middle third to facilitate coupling with the transducer. Ultrasound gel was applied in the lumen of the probe, prior to its placement in the graft to optimize data collection. The electrocardiographic and flow curves were displayed in real time, on the Medi Stim BF 2004 display console (Figure 1). The median graft flow (MGF), pulsatility index (PI) and the percentage of diastolic filling (DF) were obtained 285


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simultaneously, immediately before closing the chest, maintaining the mean arterial pressure between 70 mmHg and 100 mmHg with the use of vasoactive drugs. The median, maximum and minimum graft flows were measured in milliliters per minute. The PI was obtained by dividing the difference between the minimum and maximum by the median graft flow. Diastolic filling was defined as the percentage of the total graft flow occurred during diastole, achieved through real-time correlation with electrocardiographic curve and expressed as a percentage.

test, and for continuous variables we used the MannWhitney test. P-values <0.05 were considered statistically significant. The software SPSS version 19.0 (Inc., Chicago) was used for this analysis.

Statistical Analysis Qualified variables were described by absolute and relative frequencies. The descriptive analysis of continuous variables was performed by measuring the minimum and maximum values, means and standard deviations. To compare categorical variables we used the Fisher’s exact

Table 2. Fluxometric data of the Anterior Descending Artery Variables Coronary Flow Pulsatility Index Distolic Filling

off-pump operation n = 25 23.0(13.5/31.0) 2.3(1.75/2.65) 56.0(46.5/70.5)

on-pump operation n = 10 25.0(18.75/36.25) 2.2(1.88/2.83) 59.5(52.5/64.25)

P 0.34 0.82 0.86

EC: Extracorporeal circulation. Data expressed as median and interquartile range (Q1/Q3)

Fig. 2 - Comparison of the ADA mean flow between groups of offpump CAGB (0) and pump CABG groups (1). ADA rate: average flow of the ADA expressed in mL / min, EC: Extracorporeal circulation, CABG: coronary artery bypass grafting

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RESULTS The groups studied were similar regarding demographic and clinical characteristics (Table 1). In 35 operated patients, 80 grafts were used, and among them, 35 LITA. Out of the 80 grafts used, 39 were intended to the revascularization of the anterior wall, 21 for the side wall and 20 for the inferior wall. There were no deaths, myocardial infarction or need for percutaneous interventions during a 30-day postoperative period. The average number of distal anastomoses was 2.3 ± 0, 8 per patient in the group without EC and 2.2 ± 0.6 in the group with EC, showing no significant difference (P = 0.10). The off-pump group showed a smaller proportion of patients with triple vessel pattern, but without any statistically significant difference. There was no need to redo the anastomosis in this series. The averages of the fluxometric anastomosis are shown in Table 2. The median graft flow ranged from 9 mL / min and 69 mL / min with a mean of 25.8 ± 2.1 mL / min. Compared to the on-pump group, the mean of the variable graft flow was 18.8% lower in the off-pump group, but without any statistically significant difference (Figure 2). The percentage of diastolic filling ranged between 17% and 86% with an average of 56.9 ± 2.7%. The average of the variable diastolic filling was 2.2% lower in the off-pump group (Figure 3).

Fig. 3 - Comparison of the percentage of diastolic filling of the ADA among the off-pump CABG (0) and pump CABG groups (1). DF_ADA: percentage of diastolic filling of ADA, EC: Extracorporeal Circulation, CABG: coronary artery bypass grafting


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The PI ranged from 1.2 to 6.8, averaging 2.5 ± 0.2, and two patients had a PI> 5.0, a group with EC and without EC (5.6 and 6.8, respectively). The PI mean was 7.5% lower in the group without EC, but without any statistical significant difference (Figure 4).

pump group, and 98.1% in the on-pump group. The gold standard for evaluating the patency of anastomoses is the coronary angiography, which can also obtain other variables such as coronary flow using intracoronary ultrasound, but the need for hybrid operating rooms, familiarity with the method, use of nephrotoxic contrast agents and increased surgical time allow the application of this method for the postoperative period [19]. In the intraoperative period, methods such as thermal angiography and Doppler measurements are technically difficult and present a significant variation of results. In clinical practice, two methods remain as the most widely used nowadays in the intraoperative verification of anastomotic patency: an intraoperative fluorescence and transit-time flowmetry (TTF) [11]. The present study was designed to compare intraoperative fluxometric values of LITA-ADA grafts by TTF in a homogeneous population of consecutive patients operated on with or without EC by a single surgical team. This method proves to be quite sensitive in detecting early anastomoses with moderate degree of stenosis, and its sensitivity is increased when the data are analyzed individually, taking into account the coronary arteries patterns [13]. Flow values measured by TTF in groups of patients operated with and without EC were reported in previous studies. Schmitz et al. [20] reported graft flow values of LITA-ADA in the off-pump group, with an average of 27.92 ml / min, values which are smaller than those observed in the on-pump group, in which the average value was 40.25 ± 22.92 ml / min. This difference was attributed to secondary coronary vasodilation to acidosis during EC and less need for use of noradrenaline in this group. In this study, no difference was observed between the groups, similar to findings reported by Hassanein et al. [21] and Leong et al. [12]. The median graft flow of the LITA-ADA recorded by these authors was 42.9 ± 26.0 ml / min and 35.0 ± 24.4 ml / min in the on-pump group and 41.6 ± 25.3 ml / min and 39.6 ± 21.9 ml / min in the off-pump group, respectively. In 2004, Kjaergard et al. [15] found flow values lower than those found in the studies cited above, without any statistically significant difference between groups, values that were similar to those found in our study. These findings may be related to the measurement variability inherent in the method. The diastolic filling is the graft flow percentage which takes place during diastole, and this flow should be greater than or equal to 50% of the grafts flow [11]. In our study, we found that the median diastolic filling was greater than 50% in both groups, but no statistically significant difference was noticed. The PI is a dynamic parameter [13] that estimates the vascular resistance to the graft flow. In general, values above

Fig. 4 - Comparison of PI of the ADA between off-pump CABG (0) and pump CABG groups (1). PI_ADA: Pulsatility index of ADA, EC: Extracorporeal Circulation, CABG: coronary artery bypass grafting

DISCUSSION The use of EC produces a static and bloodless surgical field, allowing a safe anastomonic confection. However, this feature is identified as a major determinant of perioperative morbidity, length of stay and hospital costs [10,15]. As a result, off-pump CABG was reintroduced in surgical practice and its use encouraged by the availability of efficient epicardial stabilizers [16,17]. In Brazil, Lima et al. [14] reported the experience of over three thousand patients operated without EC, showing low morbimortality rates during hospitalization. In recent studies comparing the two methods in the treatment of patients with multivessel disease, patients operated without EC tended to receive fewer grafts than planned, and the rates of postoperative patency of saphenous vein grafts made in the lateral and inferior walls of the heart were significantly lower. In 2009, Shroyer et al. [10] demonstrated patency rates of 95% of the anastomosis of the LITA-ADA, with no statistically significant difference between patients operated with and without EC. Similar results were obtained in 2004 by Widimisky et al. [16], who reported patency rates of 91% in both groups, and by Puskas et al. [18], who reported a 94.1% patency in the off-

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five are considered unsatisfactory and may be related to technical problems for anastomosis [11]. In the present study, we found PI mean values of 2.68 ± 1.52 in the onpump group and 2.48 ± 1.05 in the off-pump group, without any statistically significant difference between them. In two cases, PI values> 5.0 were found, and due to the characteristic flow curve and the quality of the distal coronary bed, anastomosis was not redone. The PI is influenced by any factor that increases the flow resistance in patients with bad distal bed or with coronary microvascular disease [11]. Hassanein et al. [21] found values of PI of 1.98 ± 1.08 in the on-pump group and 2.06 ± 1.26 in the off-pump group, with no difference between groups, values similar to the findings in this study. In Brazil, there are no publications related to the use of TTF for evaluation of coronary grafts. Castro Neto et al. [19] evaluated blood flow in composite grafts of the LITA with radial artery using intracoronary ultrasound in the postoperative period, showing no statistical difference of the total flow offered to the territory of the left coronary artery revascularized with these grafts, when compared to single grafts. In 2004, Lobo Filho et al. [22] evaluated Ycomposite LITA grafts with saphenous vein, using transthoracic echocardiography with Doppler, placing the transducer in the left supraclavicular fossa demonstrating an increased flow of the LITA graft compound, which may represent a positive remodeling during the postoperative period. The flow values obtained using the TTF are influenced by several factors such as blood pressure, hematocrit and graft diameter. Two factors are particularly relevant: the native coronary artery flow, related to your degree of stenosis, and the resistance of the distal vascular bed [11]. Moreover, the PI is a good indicator of the flow pattern and, consequently, the anastomosis quality, and the possible presence of this technical problem during its making increases in the presence of PI values above 5. It is relevant to emphasize that, the assessment of this variable should be individualized, taking into consideration the quality of the distal vascular bed, and the presence of electrocardiographic changes and hemodynamic instability in the decision to redo the anastomosis [21]. The present study demonstrated through fluxometric data that there was no difference in the quality of the anastomosis between the LITA-ADA groups. This finding may be related to a greater accessibility of ADA compared to the sidewall and inferior heart arteries, regardless of the technique used, thereby reproducing the results of an onpump surgery. We believe that cases of isolated intervention in ADA are in the best indication for off-pump CABG.

patients in the group with EC. Moreover, considering that the two groups were not randomized, it may have been a selection bias affecting the results. This study describes only graft flows in the operating room, thus the results may not necessarily reflect the flow rates in the long term, in both groups. Nevertheless, it is a pioneer study in Brazil, with fluxometric comparative data analysis in patients undergoing both on-pump and off-pump CABG.

Limitations This is an observational study with a small number of 288

CONCLUSIONS There was no difference in the fluxometric parameters (FME, and IP ED) found at the anastomosis between the left internal thoracic artery and left anterior descending artery in patients undergoing CABG with and without CPB.

REFERENCES 1. Buffolo E, Lima RC, Salerno TA. Myocardial revascularization without cardiopulmonary bypass: historical background and thirty-year experience. Rev Bras Cir Cardiovasc. 2011;26(3):III-VII. 2. Hijazi EM. Is it time to adopt beating-heart coronary artery bypass grafting? A review of literature Rev Bras Cir Cardiovasc. 2010;25(3):393-402. 3. Sá MPBO, Lima LP, Rueda FG, Escobar RR, Cavalcanti PEF, Thé ECS, et al. Estudo comparativo entre cirurgia de revascularização miocárdica com e sem circulação extracorpórea em mulheres. Rev Bras Cir Cardiovasc. 2010;25(2):238-44. 4. Gabriel EA, Locali RF, Matsuoka PK, Cherbo T, Buffolo E. Revascularização miocárdica com circulação extracorpórea; aspectos bioquímicos, hormonais e celulares. Rev Bras Cir Cardiovasc. 2011;26(4):525-31. 5. Puskas JD, Williams WH, Mahoney EM, Huber PR, Block PC, Duke PG, et al. Off-pump vs conventional coronary artery bypass grafting: early and 1-year graft patency, cost, and quality-of-life outcomes: a randomized trial. JAMA. 2004;291(15):1841-9.


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6. Hernandez F, Cohn WE, Baribeau YR, Tryzelaar JF, Charlesworth DC, Clough RA, Northern New England Cardiovascular Disease Study Group, et al. In-hospital outcomes of off-pump versus onpump coronary artery bypass procedures: a multicenter experience. Ann Thorac Surg. 2001;72(5):1528-33.

16. Widimsky P, Straka Z, Stros P, Jirasek K, Dvorak J, Votava J, et al. One-year coronary bypass graft patency: a randomized comparison between off-pump and on-pump surgery angiographic results of the PRAGUE-4 trial. Circulation. 2004;110(22):3418-23.

7. Khan NE, De Souza A, Mister R, Flather M, Clague J, Davies S, et al. A randomized comparison of off-pump and on-pump multivessel coronary-artery bypass surgery. N Engl J Med. 2004;350(1):21-8.

17. van Dijk D, Diephuis JC, Nierich AP, Keizer AM, Kalkman CJ. Beating heart versus conventional cardiopulmonary bypass: the octopus experience: a randomized comparison of 281 patients undergoing coronary artery bypass surgery with or without cardiopulmonary bypass. Semin Cardiothorac Vasc Anesth. 2006;10(2):167-70.

8. Nathoe HM, van Dijk D, Jansen EW, Suyker WJ, Diephuis JC, van Boven WJ; Octopus Study Group, et al. A comparison of on-pump and off-pump coronary bypass surgery in lowrisk patients. N Engl J Med. 2003;348(5):394-402. 9. Buffolo E, Andrade CS, Branco JN, Teles CA, Aguiar LF, Gomes WJ. Coronary artery bypass grafting without cardiopulmonary bypass. Ann Thorac Surg. 1996;61(1):63-6. 10. Shroyer AL, Grover FL, Hattler B, Collins JF, McDonald GO, Kozora E, et al. On-pump versus off-pump coronary-artery bypass surgery. N Engl J Med. 2009;361(19):1827-37. 11. Balacumaraswami L, Taggart DP. Intraoperative imaging techniques to assess coronary artery bypass graft patency. Ann Thorac Surg. 2007;83(6):2251-7. 12. Leong DK, Ashok V, Nishkantha A, Shan YH, Sim EK. Transittime flow measurement is essential in coronary artery bypass grafting. Ann Thorac Surg. 2005;79(3):854-7. 13. D’Ancona G, Karamanoukian HL, Salerno TA, Schmid S, Bergsland J. Flow measurement in coronary surgery. Heart Surg Forum. 1999;2(2):121-4. 14. Lima RC, Escobar MAS, Lobo Filho JG, Diniz R, Saraiva A, Césio A, et al. Resultados cirúrgicos na revascularização do miocárdio sem circulação extracorpórea: análise de 3.410 pacientes. Rev Bras Cir Cardiovasc. 2003;18(3):261-7. 15. Kjaergard HK, Irmukhamedov A, Christensen JB, Schmidt TA. Flow in coronary bypass conduits on-pump and offpump. Ann Thorac Surg. 2004;78(6):2054-6.

18. Puskas JD, Williams WH, Duke PG, Staples JR, Glas KE, Marshall JJ, et al. Off-pump coronary artery bypass grafting provides complete revascularization with reduced myocardial injury, transfusion requirements, and length of stay: a prospective randomized comparison of two hundred unselected patients undergoing off-pump versus conventional coronary artery bypass grafting. J Thorac Cardiovasc Surg. 2003;125(4):797-808. 19. Castro Neto JV, Chaccur P, Carvalho AR, Staico R, Albertal M, Farran J, et al. Revascularização cirúrgica do miocárdio com enxerto composto de artéria torácica interna esquerda e radial: comparação do fluxo sanguíneo para artéria coronária esquerda com a técnica convencional. Rev Bras Cir Cardiovasc. 2004;19(4):365-71. 20. Schmitz C, Ashraf O, Schiller W, Preusse CJ, Esmailzadeh B, Likungu JA, et al. Transit time flow measurement in on-pump and off-pump coronary artery surgery. J Thorac Cardiovasc Surg. 2003;126(3):645-50. 21. Hassanein W, Albert AA, Arnrich B, Walter J, Ennker IC, Rosendahl U, et al. Intraoperative transit time flow measurement: off-pump versus on-pump coronary artery bypass. Ann Thorac Surg. 2005;80(6):2155-61. 22. Lobo Filho JG, Leitão MCA, Lobo Filho HG, Silva AA, Machado JJA, Forte AJV, et al. Revascularização miocárdica com enxerto composto de artéria torácica interna esquerda em Y: Análise de fluxo sanguíneo. Rev Bras Cir Cardiovasc. 2004;19(1):1-8.

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ORIGINAL ARTICLE

Rev Bras Cir Cardiovasc 2012;27(2):290-5

Initial experience with Pomerantzeff´s technique for reduction of the size of giant left atrium Experiência inicial com a técnica de Pomerantzeff para redução do tamanho do átrio esquerdo gigante

Jocerlano Santos de Sousa1, Pablo Maria Alberto Pomerantzeff2, Carlos Manuel de Almeida Brandão3, Lisandro Azeredo Gonçalves4, Marcos Gradim Tiveron5, Marcelo Luiz Campos Vieira6, Flavio Tarasoutchi7, Noedir Antônio Groppo Stolf8

DOI: 10.5935/1678-9741.20120046

RBCCV 44205-1383

Abstract Introduction: The most common indication for surgical correction of giant left atrium is associated with mitral valve insufficiency with or without atrial fibrillation. Several techniques for this purpose are already described with varying results. Objective: To present the initial experience with the tangential triangular resection technique (Pomerantzeff). Methods: From 2002 to 2010, four patients underwent mitral valve operation with reduction of left atrial volume by the technique of triangular resection tangential in our service. Three patients were female. The age ranged from 21 to 51 years old. The four patients presented with atrial fibrillation. Ejection fraction of left ventricle preoperatively ranged from 38% to 62%. The left atrial diameter ranged from 78mm to 140mm. After treatment of mitral dysfunction, the left atrium was reduced by

resecting triangular tangential posterior wall between the pulmonary veins to avoid distortion of the mitral valve or pulmonary veins anatomies, reducing tension in the suture line. Results: Average hospital stay was 21.5 ± 6.5 days. The mean cardiopulmonary bypass time was 130 ± 30 minutes. There was no surgical bleeding or mortality in the postoperative period. All patients had sinus rhythm restored in the output of cardiopulmonary bypass, maintaining this rate postoperatively. The average diameter of the left atrium was reduced by 50.5% ± 19.5%. The left ventricular ejection fraction improved in all patients. Conclusion: Initial results with this technique have shown effective reduction of the left atrium.

1. Residency in general surgery, cardiovascular surgery resident at the Heart Institute, Hospital das Clínicas, School of Medicine, University of São Paulo (HC-InCor-USP), São Paulo, Brazil. 2. Associate Professor of Cardiovascular Surgery, School of Medicine, University of São Paulo (USP), Director of the Surgical Unit of InCor-Heart Valve Diseases HCFMUSP, Sao Paulo, Brazil. 3. Doctor of Medicine FMUSP; Physician Assistant at the Surgical Unit of InCor-Heart Valve Diseases HCFMUSP, Sao Paulo, Brazil. 4. Medical doctor and preceptor of the residency program in cardiovascular surgery FMUSP, São Paulo, Brazil. 5. Cardiovascular Surgeon, Sao Paulo, Brazil. 6. Postdoctoral degree at Tufts University NEMC in Boston, Massachusetts, United States; Physician Assistant in the Department of Echocardiography, InCor-HCFMUSP, Sao Paulo, Brazil.

7. PhD, Medical Assistant of the Clinical Division of InCorHCFMUSP, Sao Paulo, Brazil. 8. Full Professor of Cardiovascular Surgery, FMUSP, Director of Surgery Division of InCor-HCFMUSP, São Paulo, SP, Brazil.

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Descriptors: Mitral valve/surgery. Atrial fibrillation. Heart valve diseases.

Study conducted at the Heart Institute, Hospital das Clínicas, School of Medicine, University of São Paulo (HC-InCor-USP), São Paulo, Brazil. Correspondence address: Jocerlano de Sousa Santos. 1645/23 Alameda Franca Street, Jardim Paulista - Sao Paulo, Brazil Zipcode: 01422-001 E-mail: jocerlanosousa@hotmail.com Article received on October 25th, 2011 Article accepted on January 15th, 2012


Sousa JS, et al. - Initial experience with Pomerantzeff´s technique for reduction of the size of giant left atrium

Abbreviations, Acronyms & Symbols LA GLA EC Imp. Dis of ABP AF LVEF Fail LA Resection AvR MvR MbPf

Left atrium Giant left atrium Extracorporeal Circulation Important disfunction of aortic biological prosthesis Atrial fibrillation Left ventricle ejection fraction Failure Triangular tangential resection of the left atrium Aortic valve replacement Mitral valve replacement Mitral biological prosthesis fracture

Resumo Introdução: A mais comum indicação de correção cirúrgica de átrio esquerdo gigante está associada à insuficiência da valva mitral, com ou sem fibrilação atrial. Diversas técnicas para este fim já estão descritas com resultados variáveis. Objetivo: Apresentar a experiência inicial com a técnica da ressecção triangular tangencial (Pomerantzeff). Métodos: De 2002 a 2010, quatro pacientes foram submetidos a operação da valva mitral com redução do volume

INTRODUCTION Giant left atrium (AEG) is defined by most authors by the diameter of the cavity above 6.5 cm, although there is not a consensus, since some authors consider it its size ranging from 6-10 cm [1]. For Kawazoe et al. [2], the definition of this pathology is dependent on two echocardiographic findings: 1) left atrial (LA) greater than 65 mm and 2) signal compression of the posterobasal left ventricular cavity between the increased left atrial and left ventricular cavity. The increase in atrial volume associated with the consequent possibility of compression of the bronchi, lungs or the left ventricle leads to a significant cardiopulmonary dysfunction, increasing the risk of a sudden death, justifying the need for better assessment and surgical intervention [1]. According to the literature, the most common indication for surgery in cases of GLA is one associated with mitral valve insufficiency, with or without atrial fibrillation (AF). Several techniques for this purpose already described, as the LF plication, varying according to the technique of the approched atrial wall, the autotransplantation of the spiral partial heart resection and the association with the Maze procedure to any technique in order to treat AF. We present our initial experience with a tangential triangular resection described by Pomerantzeff et al.

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do átrio esquerdo pela técnica da ressecção triangular tangencial em nosso serviço. Três pacientes eram do sexo feminino. A idade variou de 21 a 51 anos. Os quatro pacientes encontravam-se com fibrilação atrial. A fração de ejeção do ventrículo esquerdo no pré-operatório variava de 38% a 62%. O diâmetro do átrio esquerdo variou de 78 a 140 mm. Após o tratamento da disfunção mitral, o átrio esquerdo foi reduzido por meio de ressecção triangular tangencial da sua parede posterior, entre as veias pulmonares, para evitar distorções anatômicas do anel mitral ou veias pulmonares, reduzindo a tensão na linha de sutura. Resultados: Tempo médio de internação hospitalar foi de 21,5 ± 6,5 dias. O tempo de circulação extracorpórea médio foi de 130 ± 30 minutos. Não houve sangramento cirúrgico ou mortalidade no período pós-operatório. Todos os pacientes tiveram o ritmo sinusal restabelecido na saída de circulação extracorpórea, mantendo esse ritmo no pós-operatório. O diâmetro médio do átrio esquerdo foi reduzido em 50,5 ± 19,5%. A fração de ejeção do ventrículo esquerdo melhorou em todas as pacientes. Conclusão: Os resultados iniciais com essa técnica têm demonstrado redução efetiva do átrio esquerdo. Descritores: Valva mitral/cirurgia. Fibrilação atrial. Doenças das valvas cardíacas.

METHODS Between 2002 and 2010, four patients underwent mitral valve surgery in combination with reduction of LA volume by the technique of tangential triangular resection at the Heart Institute, Hospital das Clinicas, School of Medicine, University of Sao Paulo. Three patients were female and one of them male. Ages ranged from 21 to 51, with an average of 37.25 years. In a patient, the congenital etiology was severe with mitral and tricuspid valve insufficiency and with GLA. In the other three, the etiology of mitral valve disease was rheumatic, in which one case was reoperation for mitral biological prosthesis replacement, and another case for second reoperation for intra-aortic and mitral prostheses replacement. In one patient, there was mitral valve repair (posterior annuloplasty), and the other three, the mitral valve was replaced by biological prosthesis. The four patients were in AF rhythm, with oral anticoagulant therapy. Ejection fraction of left ventricle in the preoperative period ranged from 38 to 62%. The LA diameter ranged from 78 to 140 mm, measured by transthoracic echocardiography (Table 1). In all patients, the access to the LA is given by the conventional approach; however, an abnormal atrial growth has made access it more difficult in a patient, since the LA would be all over the cavity, displacing all other structures. 291


Sousa JS, et al. - Initial experience with Pomerantzeff´s technique for reduction of the size of giant left atrium

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Table 1. Surgical data. Case Sex Age (years) Diagnosis Etiology Surgery

Length of hospital stay N° Surgery Preoperative rhythm Postoperative rhythm Preoperative LVEF Postoperative LVEF LA preoperative diameter LA postoperative diameter LA reduction rate

1 F 21 Tricuspid insuff; Mitral insuff; GLA Congenital Mitral valve repair; plástica de valva tricuspid valve plast; LA tang 15 days 1st AF Sinus 40% 61% (2009) 140 mm 60 mm 57%

2 F 51 Mitral insuff; AEG; Insuf. trisúspide Rheumatic Mitral valve replacement; De Vega tricuspid valve repair; LA tang 28 days 1st AF Sinus 62% 66% 134 mm 40 mm 70%

3 F 36 Insuf. mitral; GLA Rheumatic Mitral valve replacement; De Vega tricuspid valve repair; LA triang 15 days 2nd AF Sinus 45% 60% 78 mm 55 mm 30%

4 M 41 Rup. MiBio; GLA; Sig. Dys. Aobiop Rheumatic 3rd AoV Rep (Biop Nº23) + MiV Rep (Bioprosthesis Nº27); LA triang 20 days 3rd AF Sinus 38% 46% 85 mm 60 mm 30%

LA = left atrium; GLA = giant left atrium; AF = atrial fibrilation; LVEF = LVEF; Insuff. = insufficiency; LA triang = left atrium tangencial triangular resection; Rup. MiBio = rupture of the mitral bioprosthesis; Sig. Dys. Aobiop = significant dysfunction of aortic bioprosthesis; AoV Rep = aortic valve replacement; MiV Rep = mitral valve replacement

All patients underwent surgery with extracorporeal circulation (EC) and moderate hypothermia (28 ° C). EC was conventionally performed with cannulation of the aorta and superior and inferior vena cava. Myocardial protection was achieved with hypothermic blood cardioplegic solution. The LA was opened by conventional atriotomy (Figure 1). It was followed by operation with the mitral valve (Figure 2) and the treatment of dysfunction of the same (such as plastic or replacement). Then, the left atrium was reduced by means of tangential triangular resection of the posterior wall between the pulmonary veins, to avoid distortion of the mitral annulus or pulmonary veins anatomies, and then, reduce the tension on the suture line (Figures 3-6). Fig. 2 - Exploration of the mitral valve

Fig. 1 - Left atriotomy showing the increase of the cavity

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Fig. 3 - Left atrium tangencial triangular resection


Sousa JS, et al. - Initial experience with Pomerantzeff´s technique for reduction of the size of giant left atrium

Fig. 4 - Atrial tissue resected

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Fig. 6 - Final aspect of the procedure after cessation of Extracorporeal Circulation

Fig. 5 - Final aspect of the resection

Figure 7 schematically illustrates the reconstruction technique. The LA edges were sutured with the reinforcement of bovine pericardium in two patients, due to the friability of the tissues. In one patient, the tricuspid valve repair was performed through a right atriotomy bicuspidization. The patients had different follow-up periods ranging from 30 days to 8 years after surgery, in which all patients underwent intraoperative transesophageal echocardiography and transthoracic echocardiography before hospital discharge and outpatient care. RESULTS The average hospital stay was 21.5 ± 6.5 days. The EC average time was 130 ± 30 minutes. There was no mortality in the postoperative period. There were not any cases of postoperative bleeding that required surgical rapprochement. All operated patients had sinus rhythm restored since the end of the EC, and maintained that pace in the postoperative follow-up period. The atrium diameter

Fig. 7 - Schematic drawing of the reconstruction

was reduced by 50.5 ± 19.5% after surgery. The ejection fraction of left ventricle significantly improved in all patients. The patient who has 8 years of follow-up remains an ejection fraction of 62%, and preoperative was 40%. There were no thrombi in the LA through the transthoracic echocardiography during the follow-up period. The cardiac area on chest radiographs showed a significant reduction in postoperative evaluation. All patients had improvement in New York Heart Association Functional Class. The pathological examination of surgical specimens showed atrial wall replacement with fibrous myocardial hypertrophy, diffuse and focal myocytolysis of the cardiomyocytes, and fibromuscular thickening of the endocardium in all operated cases. 293


Sousa JS, et al. - Initial experience with Pomerantzeff´s technique for reduction of the size of giant left atrium

DISCUSSION The first description of GLA was made in 1849 [3] and in 1967, the first management of GLA in symptomatic patients was reported as successful. The exact etiology of GLA remains unknown, despite the strong association with chronic rheumatic disease of the mitral valve, with consequent increase of intracavitary pressure and higher pressure and dilation of the chamber, and left ventricular failure, chronic atrial fibrillation and leftright shunts (patent ductus arteriosus, ventricular septal defect, etc.). [1]. There are also isolated reports of GLA, where the inherent weakness of the atrial wall may be responsible for changes. According to Di Eusanio et al. [4], 19% of patients undergoing mitral valve surgery have GLA, demonstrating how common this abnormality is, therefore, besides the correction of valve dysfunction, we should also reduce the size of the LA. These patients usually have a long history of mitral valve disease, atrial fibrillation, palpitations, chest pain, dyspnea, hoarseness due to compression of the laryngeal nerve (Ortner syndrome) or other respiratory or hemodynamic complications. Several studies have described the correlation between the atrial diameter and atrial volume, proving that the blood stasis in the cavity leads to the formation of thrombi causing thromboembolic phenomena [5]. The main organs affected by the LA increase are bronchial and lung lobes, causing respiratory dysfunction, and esophagus, causing dysphagia, or it also may compress the descending thoracic aorta, occurring asymptomatically. The occurrence probability of intracavitary thrombus in patients with GLA associated with AF undergoing mitral valve surgery is increased [6]. The idea that mitral valve surgery alone will result in remodeling and atrial size reduction is considered wrong by most studies. The LA size is an independent predictor factor for thromboembolism [7] and for morbidity and mortality [8]. The main indications for surgery of the GLA are for those patients with indication of mitral valve surgery in cases of intra or extracardiac compression, presence of thrombi or thromboembolic events in association with Maze surgery. It is reported that patients who undergo radiofrequency surgery associated with reduced LA are more successful on the reversal to sinus rhythm than those patients who are treated with radiofrequency [1]. The plication of the posterior wall of the LA or-annular, the heart partial autotransplantation [9], the spiral resection of the atrial wall [10] and the association with the Maze procedure for any technique in order to treat AF are most common procedures in the current treatment of GLA. The unsatisfactory reduction of the size of LGA, the great time 294

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of EC, the failure of surgical treatment of AF or postoperative bleeding are potential possibilities in those proceedings. Overall mortality in surgery of the LGA associated with mitral valve surgery varies from 8% to 23% [1]. According to Kosakai [11], in patients with LGA and AF undergoing mitral valve repair procedure associated with Cox-Maze III, sinus rhythm was not restored in patients with LA diameter above 8.7 cm, while patients with a diameter of less than 4.5 cm, the LA gave 100% reversion of atrial fibrillation. So far, there is not any standard surgical technique to reduce the LA. The principles of the LA are aneurysmectomy resection and reconstruction of the cavity without distortion of the mitral valve and pulmonary veins anatomies [12]. In all cases operated in this work, the tangential triangular resection of left posterior atrial wall was carried out, following the principles of maintaining the anatomy of the atrial cavity, resulting in excellent rates of reduction of the cavity. Median sternotomy is the access of choice for reduction of the LA, especially in cases of large aneurysms, however, lateral thoracotomy or minimally invasive techniques are described in the literature [13] and use of off-pump surgical staples in isolated cases of GLA without thrombi [12]. The suture reinforcement with bovine pericardium is suggested in cases of atrial tissue with friable or chronic inflammation [14].

REFERENCES 1. Apostolakis E, Shuhaiber JH. The surgical management of giant left atrium. Eur J Cardiothorac Surg. 2008;33(2):182-90. 2. Kawazoe K, Beppu S, Takahara Y, Nakajima N, Tanaka K, Ichihashi K, et al. Surgical treatment of giant left atrium combined with mitral valvular disease. Plication procedure for reduction of compression to the left ventricle, bronchus, and pulmonary parenchyma. J Thorac Cardiovasc Surg. 1983;85(6):885-92. 3. Hewett P. Aneurysmal dilatation of left auricle with thickening and contraction of left auriculoventricular opening. Trans Pathol Soc London. 1849/1850;2-193. 4. Di Eusanio G, Gregorini R, Mazzola A, Clementi G, Procaccini B, Cavarra F, et al. Giant left atrium and mitral valve replacement: risk factor analysis. Eur J Cardiothorac Surg. 1988;2(3):151-9.


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5. Matsuda H, Nakao M, Nohara H, Higami T, Mukohara N, Asada T, et al. The causes of prolonged postoperative respiratory care in mitral valve disease with a giant left atrium. Kyobu Geka. 1990;43(3):172-7.

10. Sugiki H, Murashita T, Yasuda K, Doi H. Novel technique for volume reduction of giant left atrium: simple and effective “spiral resection” method. Ann Thorac Surg. 2006;81(1):378-80.

6. Erdogan HB, Ipek G, Kirali K, Ömeroglu SN, Güler M, Isik Ö, et al. Volume reduction procedures in giant left atrium. Asian Cardiovasc Thorac Ann. 2001;9:171-5.

11. Kosakai Y. Treatment of atrial fibrillation using the Maze procedure: the Japanese experience. Semin Thorac Cardiovasc Surg. 2000;12(1):44-52.

7. Itoh T, Okamoto H, Nimi T, Morita S, Sawazaki M, Ogawa Y, et al. Left atrial function after Cox’s maze operation concomitant with mitral valve operation. Ann Thorac Surg. 1995:60(2):354-9.

12. Pomerantzeff PM, Brandão CM, Guedes MA, Stolf NA. Tangential triangular resection: an option to treat the giant left atrium. Innovations (Phila). 2010;5(2):125-7.

8. Reed D, Abbott RD, Smucker ML, Kaul S. Prediction of outcome after mitral valve replacement in patients with symptomatic chronic mitral regurgitation. The importance of left atrial size. Circulation. 1991;84(1):23-34.

13. Kiaii B, Doll N, Kuehl M, Mohr FW. Minimal invasive endoscopic resection of a giant left atrial appendage aneurysm. Ann Thorac Surg. 2004;77(4):1437-8.

9. Lessana A, Scorsin M, Scheublé C, Raffoul R, Rescigno G. Effective reduction of a giant left atrium by partial autotransplantation. Ann Thorac Surg. 1999;67(4):1164-5.

14. Kalangos A, Ouaknine R, Hulin S, Cohen L, Lecompte Y. Pericardial reinforcement after partial atrial resection in idiopathic enlargement of the right atrium. Ann Thorac Surg. 2001;71(2):737-8.

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REVIEW ARTICLE

Rev Bras Cir Cardiovasc 2012;27(2):296-301

Point-of-care test (POCT) INR: hope or illusion? RNI Point-of-care test (POCT): esperança ou ilusão?

Luci Maria Sant’Ana Dusse1,2, Nataly Carvalho Oliveira1, Danyelle Romana Alves Rios1,3, Milena Soriano Marcolino2,4

DOI: 10.5935/1678-9741.20120047

RBCCV 44205-1384

Abstract In the last decade, point-of-care tests were developed to provide rapid generation of test results. These tests have increasingly broad applications. In the area of hemostasis, the international normalized ratio, INR point-of-care test (POCT INR), is the main test of this new proposal. This test has great potential benefit in situations where the quick INR results influences clinical decision making, as in acute ischemic stroke, before surgical procedures and during cardiac surgery. The INR POCT has the potential to be used for self-monitoring of oral anticoagulation in patients under anticoagulant therapy. However, the precision and accuracy of INR POCT still need to be enhanced to increase effectiveness and efficiency of the test. Additionally, the RDC / ANVISA Number 302 makes clear that the POCT testing must be supervised by the technical manager of the Clinical Laboratory in the pre-analytical, analytical and postanalytical. In practice, the Clinical Laboratory does not participate in the implementation of POCT testing or release of the results. Clinicians have high expectation with the incorporation of INR POCT in clinical practice, despite the limitations of this method. These professionals are willing to train the patient to perform the test, but are not legally responsible for the quality of it and are not prepared for the maintenance of equipment.

The definition of who is in charge for the test must be one to ensure the quality control.

1. PhD, Department of Clinical and Toxicological Analysis, School of Pharmacy, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil. 2. Specialist; Biomedicine at the Federal University of Minas Gerais, Belo Horizonte, MG, Brazil. 3. PhD, Federal University of Sao Joao del Rei, Sao Joao del Rei, MG, Brazil. 4. PhD, Anticoagulation Clinic of Odilon Behrens Hospital/ Municipality of Belo Horizonte, Belo Horizonte, MG, Brazil.

Work performed at the School of Pharmacy, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil.

296

Descriptors: Thrombosis. Clinical laboratory techniques. Prothrombin time. Resumo Na última década, foram desenvolvidos os testes point-ofcare visando à geração rápida de resultados de exames. Na área da hemostasia, a razão normatizada internacional, o RNI point-of-care test (RNI-POCT), constitui o principal exame dessa nova proposta. Esse teste tem grande potencial de benefício em situações em que o resultado rápido da RNI influencia a tomada de decisão clínica, como no acidente vascular cerebral isquêmico agudo, antes de procedimentos cirúrgicos e durante cirurgias cardíacas, além de permitir que o próprio paciente faça a monitoração da anticoagulação oral. Entretanto, a precisão e a acurácia da RNI-POCT ainda precisam ser aprimoradas para aumentar a eficácia e a eficiência do teste. A RDC/ANVISA Nº 302 deixa claro que os testes POCT devem ser supervisionados pelo responsável técnico do Laboratório Clínico nas fases pré-analítica, analítica e pós-analítica. Na prática, o laboratório não participa da execução desses testes e liberação dos resultados, não sendo, portanto, o mais indicado para garantir a qualidade dos mesmos. Os clínicos, especialmente aqueles envolvidos com

Mailing address: Luci Maria Santana Dusse 6627 Antonio Carlos Avenue, Room 4104 - B3 - Campus Pampulha - Belo Horizonte, MG, Brazil - CEP: 31270-901 E-mail: lucidusse@gmail.com Article received on February 14, 2012 Article accepted on June 11, 2012


Dusse LMSA, et al. - Point-of-care test (POCT) INR: hope or illusion?

Abbreviations, acronyms & symbols C VA CNPq FAPEMIG ISR INR-POCT RR RTL PT

Cerebrovascular Accident National Council for Scientific and Technological Development Research Support Foundation of the State of Minas Gerais International standardization reason INR point-of-care test Relative risk Remote test laboratory Prothrombin time

INTRODUCTION Oral anticoagulants are used in secondary prevention of thromboembolic events in patients with venous or arterial thrombosis and those with heart disease that may predispose to thrombus formation. The indications for long term use of oral anticoagulants have been increasing as medical conditions that predispose to thromboembolic events are detected [1]. Silva et al. [2] found that prophylactic oral anticoagulation was safe and significantly reduced the incidence of venous thrombosis after implantation of electronic cardiac devices in high-risk patients (RR: 0.57, 95% CI: 0.33 to 0.98). In addition to ensuring the treatment efficiency, regular monitoring of oral anticoagulation should ensure the prevention of hemorrhagic phenomena [3]. The prothrombin time test (PT) is sensitive to reductions in coagulation factors II, VII and X. The INR calibration model (international normalization ratio), adopted in 1982, has since been used in a standardized way to report the results of PT, measured with the thromboplastin used in each laboratory [4]. According to Rosendaal [5], control of oral anticoagulation should be performed by specialized clinics to minimize risks and improve the practice. Chiquette et al. [6] compared to conventional care anticoagulation control, the regular attendance at a clinic and a follow-up period at specialized clinics for anticoagulation control. Rates of occurrence of smaller events were found in specialized clinics, both for thromboembolic accidents and for bleeding episodes. Campos et al. [7] proposed that the objectives of a specific follow-up clinic for oral anticoagulation would be

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a anticoagulação oral de pacientes, têm grande expectativa na incorporação da RNI-POCT na prática diária, apesar das limitações desse método. Esses profissionais mostram-se dispostos a treinar o paciente para realizar o teste, mas legalmente não são os responsáveis pela qualidade do mesmo e não estão preparados para a manutenção dos equipamentos. A definição do responsável pelo RNI-POCT precisa ser reavaliada pelos órgãos competentes, de forma a garantir que seja cumprida, e constitui etapa essencial para assegurar a qualidade do teste e, consequentemente, sua maior utilização. Descritores: Trombose. Técnicas de laboratório clínico. Tempo de protrombina.

achieved when patients remained most of the time with their INR within the desired ranges, or the percentage of tests with the desired INR increasing. In the last decade, the point of care test were developed, known as near patient or bedside testing, aimed at the rapid generation of test results, to enable effective clinical decision making in a short time. These tests have increasingly broad applications. In the area of hemostasis, the PT expressed in INR, INR point of care test (INR-POCT), is the main consideration of this new proposal [8,9]. Recently, several automated or semi-automated portable coagulometer have been developed to determine the INR samples collected by venous or digital puncture. The procedure consists of applying a drop of in a disposable cartridge containing thromboplastin which then is introduced into the coagulometer that detects clot formation. PRINCIPLES OF DETERMINATION OF INR-POCT Different principles have been used to detect clot formation in the portable coagulometer: 1. Monitoring thrombin generation by a substrate cleavage A drop of blood is added to the reaction chamber of the equipment and the process of coagulation is triggered by the contact of the sample factor VII with calcium thromboplastin. The sequential activation of factor X, factor V in the presence of calcium ions results in conversion of prothrombin into thrombin. Thrombin acts on the formed HD-phenylalanyl-pipecolyl-arginine-p-amino-pmethoxydiphenylamine (Phe - pipecolic acid - Arginine 297


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NH - C6H4 - NH - C6H4 - OCH3) and cleave the amide bond on the carboxyl terminal region of the arginine residue. This region is structurally similar to that present in the molecule of fibrinogen, which is cleaved by thrombin to generate fibrin monomers. The thrombin-substrate reaction generates the electrochemically inert tripeptide (Phe Pipecolina - arginine) and the electroactive compound (NH3 @ + - C6H4 - NH - C6H4 - OCH3), which is detected by amperage. This time represents the thrombin generation period [10]. 2. Monitoring capillary blood flow A drop of blood is added to a single use cartridge which is inserted in a portable coagulometer. By capillarity, blood flows into the reaction chamber, which contains thromboplastin obtained from rabbit brain. Factor VII activation is present in the blood sample, triggering the coagulation cascade. When fibrinogen is broken into fibrin monomers, there is a reduction of blood flow velocity, which is optically monitored by a laser and displayed in seconds. This value is in seconds, then converted to INR [11]. 3. Motion detection of metal particles in a magnetic field and light reflection The test strip contains thromboplastin and particles of iron oxide. The blood drop applied to the coagulometer, by capillarity, goes to the area of reaction at 37 ° C. The coagulation process is initiated by the contact of the sample factor VII with calcium thromboplastin. This machine has two magnets located below the test strip, a permanent magnet, which promotes the horizontal alignment of the iron particles, and an electromagnet, which promotes the vertical alignment of them originating a regular pulse magnetic field. A photodetector above the test strip records the change caused by this pattern of pulsation in the reflected light. Once initiates the formation of the fibrin clot, the movement of the iron particles decreases, and consequently reduces the light reflection. The coagulometer accurately detects the beginning of the reduction in light reflection, which coincides with the beginning of the formation of fibrin. An algorithm programmed into the chip device converts the start of the reduction of light reflection to INR [5]. The principle of coagulometer detection of clot formation has an impact on the outcome of the obtained INR, so that the equipment employing the capillary blood flow tend to provide lower INR values of samples with increased viscosity, particularly when hematocrit is more than 55% [5].

prior to administration of thrombolytic therapy in patients with acute ischemic cerebrovascular accident (CVA). The efficacy of thrombolysis in acute cerebrovascular accidents strongly depends on the interval between the onset of symptoms and administration of thrombolytic therapy [12]. Rizos et al. [13] observed significant and clinically relevant time to onset of thrombolytic therapy, 28 ± 12 minutes with the use of INR-POCT. The use of INR-POCT also allows the reduction of problems related to venipuncture, particularly in patients with difficult venous access and in children, the difficulty of puncture can cause errors in results of blood coagulation [14]. Moreover, it represents greater convenience for patients, especially those who live in remote locations having to go to the laboratory to measure the INR [7,8]. Another great advantage of INR-POCT is the limitation of the indication of fresh frozen plasma in cardiac surgery, because the INR monitoring throughout surgery clinical team would provide the correct information related to the need for replacement of coagulation factors [9.15,16]. A systematic review of the Cochrane Database, which included 18 studies involving patients with oral anticoagulation monitored by INR-POCT, showed improvement in the control of anticoagulant therapy, and reduction of thromboembolic events and mortality. This study also included the evaluation of the adjustment of the dose of warfarin made by the patient (according to the result of the INR-POCT) and adjusting the dose of warfarin made by the clinician (prior knowledge of INR-POCT value). There was no difference in incidence of new thromboembolic events and bleeding, which showed that patients were able to correctly adjust the anticoagulant dose. However, the authors warned that not all patients are capable of performing the monitoring of anticoagulant therapy [10].

The INR-POCT advantages The main advantage of INR-POCT is the determination of the fast result, which can have great impact on medical management. An example is the determination of INR POCT298

PROBLEMS ASSOCIATED WITH INR-POCT The major problem related to INR-POCT is the accuracy in relation to the reference method, the conventional prothrombin time. When a POCT device is validated, the criteria commonly used to assess the concordance between the two methods are INR-POCT values and the reference method in the same clinical category (in other words, both values within, above or below the therapeutic range), or an 0.4 INR difference between the methods, or even 85% of paired results in the therapeutic range should have a difference of ± 0.5 INR between the methods. According to the International Standards Organization criteria when the INR is lower than 2.0, it is desirable that more than 90% of the results have a difference of ± 0.5 INR, when the INR is greater than 2.0, the results matched should differ by no more than 30% [17]. Such criteria may


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not be suitable for patients receiving vitamin K inhibitor, since the results with a Âą 0.2 INR difference of the therapeutic range require medication dosege change. Thus, even if a INR-POCT has adequate accuracy, according to the criteria set, this accuracy can be insufficient in patients receiving vitamin K inhibitor, once the small differences between the methods can result in an inappropriate dosage change and risk of adverse events such as thromboembolism or bleeding [18-21]. Furthermore, even for those tests that follow this standardization, the results vary among manufacturers. The most commonly used guidelines for the management of patients using vitamin K inhibitor, the American College of Chest Physicians suggest that health professionals who choose to use INR-POCTin their patients should be careful to evaluate this test periodically comparing the results with the reference method, once or twice per year for each patient in order to evaluate the discrepancy in relation to the reference method [22]. It is known that the accuracy of INR-POCT is lower for INR values above 3.5 and it even decreases to values above 4.5. The International Sensitivity Index Calibration System approves INR-POCT results only when the values are lower than 4.5 [10]. Thus, this test is not suitable for patients with valve metal, for which the therapeutic range of INR is between 2.5 and 3.5 [23]. Another difficulty associated with the use of INR-POCT is the cost of the exam (it is still much higher than the reference method), to obtain sufficient volume of blood through digital puncture (coagulation analyzers available on the market require 3-50 mL of blood). Tests which require more blood may induce compression to increase the puncture site bleeding, which is not desirable, since it changes the test results [10]. In addition to these limitations, some patients have difficulty in collecting the blood drop and snap the cartridge into the coagulometer, particularly for individuals with arthritis or tremors [8]. Therefore, it is necessary to repeat test, which further increases its cost. Another factor limiting the use of INR-POCT is the presence of antiphospholipid antibodies in the sample. These antibodies neutralize phospholipids included in the test to begin the cascade activation of coagulation factors, slowing down time for the formation of thrombin and thus interfere with the results provided by the devices that monitor the generation of thrombin and a subsequent substrate cleavage [ 24]. Other factors that may influence are the presence of hyperbilirubinemia (> 170 mmol / L) and hypertriglyceridemia (> 5 mmol / L), which interfere in the blood viscosity and therefore in the results of the equipment that determines both blood electromagnetic impedance change, such as those that monitor capillary blood flow and detect the movement of metal particles in a magnetic field and reflect the light [10,15]. The presence of heparin in the sample is another

problem, since there are no reagents to counteract its action. Heparin can extend the time required for the formation of thrombin, interfering with the output of the devices that monitor the generation of thrombin and a subsequent substrate cleavage [10]. FINAL CONSIDERATIONS In recent years, several factors have contributed to the development of equipment for POCT. The evolution of technology has allowed the production of miniature components of equipment such as sensors, transducers and detectors. This has enabled the production of portable coagulation by several companies that generally have no trouble handling. The development of software that manages information such as calibration curves, parameters of quality control, patient outcomes, and demographic data has also contributed to the efficiency of portable coagulation. Some systems allow the evaluation of operator performance in accordance with various regulatory requirements and validation of analytical data. Newer systems are associated with software that allows the transfer of patient results and quality control to a database. The recognition of the benefits of an integrated database to laboratory diagnosis is boosting the development of hardware and software enabling the electronic transfer of the POCT outcome to an information system so that doctors have quick access to them, which allows them to promptly establish the necessary therapeutic interference. Despite the promising aspects for the development of POCT, an unanswered question is about the definition of a responsible person for implementation and quality assurance of these tests. The resolution - RDC / ANVISA No. 302 [19], transcribed below makes clear that POCT tests, called remote test laboratory (RTL), must be supervised by the technical manager of the Clinical Laboratory in the pre-analytical, analytical and postanalytical phase. In practice, the laboratory does not participate in the implementation of POCT testing and release of results, it is not, therefore, the best one to ensure their quality. Clinicians, especially those involved with oral anticoagulation of patients, have high expectations of INR POCT introduction in daily practice, despite the limitations of this method. These professionals are willing to train the patient to perform the test, but are not legally responsible for the quality of the work and are not prepared for the equipment maintenance. Resolution - RDC / ANVISA No.. 302 of October,13th 2005 (19) 6.2.13 The implementation of the Remote Tests Laboratory - RTL (Point-of-care) and rapid tests, should be linked to a clinical laboratory, collection station or public health service or hospital outpatient. 299


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6.2.14 The Technical Manager is responsible for the clinical laboratory by all RTL conducted within the institution, or any location, including, among others, visits to the day hospital, home and laboratory collected at the mobile unit. 6.2.15 The relationship of RTL that performs clinical laboratory should be available to the local health authority. 6.2.15.1 The clinical laboratory must provide documented procedures regarding their pre-analytical, analytical and post-analytical phases, including: a) systematic registration and release of preliminary results; b) procedure for potentially critical results; c) systematic review of results and release of reports by a qualified professional. 6.2.15.2 The performance of RTL and the rapid tests is subject to the issue of decisions that determine their diagnostic limitations and other information set out in item 6.3. 6.2.15.3 The clinical laboratory must maintain records of quality controls and procedures for their implementation. 6.2.15.4 The clinical laboratory must promote and maintain records of their continued education for users of RTL equipment. CONCLUSION The use of INR-POCT has great potential benefit in situations where the result of rapid INR influences clinical decision making, as in acute ischemic cerebrovascular accident (CVA), surgical procedures before and during cardiac surgery. Moreover, it has the potential to be used by patients to monitor oral anticoagulation, which can help increase patient adherence to treatment, since it facilitates the understanding of the importance of controlling the INR and the risks associated with this therapy. However, the precision and accuracy of INR-POCT still need to be improved to increase effectiveness and efficiency of the test. The definition of a responsible person for quality assurance of INR-POCT, in pre-analytical, analytical and post-analytical phases, needs to be reevaluated by the competent organs, in order to ensure it is going to be fulfilled. Undoubtedly, it constitutes an essential step to ensure the quality of this test and consequently, its greater use. ACKNOWLEDGMENTS Our special thanks go to the Research Support Foundation of the State of Minas Gerais (FAPEMIG) and the National Council for Scientific and Technological Development (CNPq). 300

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on international normalized ratio measurements with two point-of-care testing devices and a reference laboratory measurement. Pharmacotherapy. 2002;22(11):1397-404.

14. Moon JR, Jeong SI, Huh J, Lee HJ, Park PW, Kang IS. Accuracy of CoaguChek XS for point-of-care antithrombotic monitoring in children with heart disease. Ann Clin Lab Sci. 2010;40(3):247-51. 15. Samama CM, Ozier Y. Near-patient testing of haemostasis in the operating theatre: an approach to appropriate use of blood in surgery. Vox Sang. 2003;84(4):251-5. 16. Solvik UO, Stavelin A, Christensen NG, Sandberg S. External quality assessment of prothrombin time: the split-sample model compared with external quality assessment with commercial control material. Scand J Clin Lab Invest. 2006;66(4):337-49. 17. Van Cott EM. Point-of-care testing in coagulation. Clin Lab Med. 2009;29(3):543-53. 18. Hobbs FD, Fitzmaurice DA, Murray ET, Holder R, Rose PE, Roper JL. Is the international normalised ratio (INR) reliable? A trial of comparative measurements in hospital laboratory and primary care settings. J Clin Pathol. 1999;52(7):494-7. 19. Shermock KM, Bragg L, Connor JT, Fink J, Mazzoli G, KottkeMarchant K. Differences in warfarin dosing decisions based

20. McBane RD 2nd, Felty CL, Hartgers ML, Chaudhry R, Beyer LK, Santrach PJ. Importance of device evaluation for pointof-care prothrombin time international normalized ratio testing programs. Mayo Clin Proc. 2005;80(2):181-6. 21. Ryan F, O’Shea S, Byrne S. The reliability of point-of-care prothrombin time testing. A comparison of CoaguChek S and XS INR measurements with hospital laboratory monitoring. Int J Lab Hematol. 2010;32(1 Pt 1):e26-33. 22. Ansell J, Hirsh J, Hylek E, Jacobson A, Crowther M, Palareti G; American College of Chest Physicians. Pharmacology and management of the vitamin K antagonists: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Chest. 2008;133(6 Suppl):160S-198S. 23. Salem DN, O’Gara PT, Madias C, Pauker SG; American College of Chest Physicians. Valvular and structural heart disease: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Chest. 2008;133(6 Suppl):593S-629S. 24. Perry SL, Samsa GP, Ortel TL. Point-of-care testing of the international normalized ratio in patients with antiphospholipid antibodies. Thromb Haemost. 2005;94(6):1196-202.

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REVIEW ARTICLE

Cardiology in Brazilian scientific journals: an overview Cardiologia em revistas científicas brasileiras: um panorama

Kavita Kirankumar Patel1, Mauricio Rocha e Silva2

DOI: 10.5935/1678-9741.20120048 Abstract Cardiology has been and is a very significant fraction of the Brazilian contribution to science. In older days, the most significant part of this work was directed to foreign periodicals, but the quasi-simultaneous emergence of SciELO and PUBMED has ordained a redirection of much of this work to Brazilian periodicals. We here survey some of this more recent contribution for the benefit of readers of Revista Brasileira de Cirurgia Cardiovascular. This is offered as an update. Articles on the general themes of Cardiology and Pneumology published by four ISI Indexed Brazilian journals not specializing in cardiology are re-visited, after a search through 10 journals.

INTRODUCTION Medical scientific Brazilian journals are going through a phase of improved quality and visibility. This is the result of the rise in Brazilian scientific production and to fifteen years of the beneficial influence of SciELO, the Scientific Electronic Library Online and of the introduction of totally open access to the file of the National Library of Medicine brought about by PUBMED. The increase in the number of ISI-THOMSON indexed journals must also be regarded as a contributing factor. This is a review of papers recently published in non-cardiologic journals on the theme of

1. Editorial Director of the Scientific Journal CLINICS, Faculdade de Medicina and Hospital das Clínicas, Universidade de São Paulo, SP, Brazil 2. Editor-in-Chief of the Scientific Journal CLINICS, Faculdade de Medicina and Hospital das Clínicas, Universidade de São Paulo, SP, Brazil Work released at Hospital das Clínicas, Faculty of Medicine University of São Paulo, São Paulo, SP, Brazil.

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RBCCV 44205-1385 Resumo A Cardiologia foi, e continua sendo, responsável por uma fracção muito significativa da contribuição brasileira para a ciência. No passado, os trabalhos mais importantes eram direcionados para periódicos estrangeiros, mas o surgimento quase simultâneo do SciELO e PUBMED facilitou um redirecionamento de grande parte desses trabalhos a periódicos brasileiros. Neste artigo, examinamos algumas das contribuições mais recentes em benefício aos leitores da Revista Brasileira de Cirurgia Cardiovascular. Esta discussão é oferecida como uma atualização. Artigos sobre os temas gerais da cardiologia e pneumologia publicados por quatro revistas brasileiras indexadas no ISI - não especializadas em cardiologia - são revistos.

cardio-pneumology. These articles appeared in the Brazilian Journal of Medical and Biological Research, Clinics, Revista da Escola de Enfermagem da USP, and Revista Latinoamericana de Enfermagem. They were selected according to the concept of continuously variable rating: articles are selected through citations vis-à-vis papers in the same journal [1]. As might be expected the majority of selected papers cover cardiac surgery. General Review Surgery contributed 24 articles to this evaluation, where the theme of coronary artery bypass grafting is, not

Correspondence address: Kavita Kirankumar Patel. Rua Dr. Ovídio Pires de Campos, 225 – 6th floor São Paulo, SP, Brazil – Zip code 05403-010 E-mail: kavita.patel@hc.fm.usp.br

Article received on May 2nd, 2012 Article accepted on June 14th, 2012


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surprisingly, the most frequent entry. Caputti et al. [2] compared 217 nonrandomized, consecutive, and nonselected patients with left ventricular ejection fractions of less than 20% who underwent coronary artery bypass graft, with or without cardiopulmonary bypass. They found that in selected patients with severe left ventricular dysfunction the procedure is valid and safe and promotes less mortality and morbidity, compared with conventional operations. Schachner et al. [3] endeavored to determine the influence of preoperative serum N-terminal fragment of pro-brain type natriuretic peptide (an established biomarker for cardiac failure) on postoperative outcome and mid-term survival in 819 patients undergoing isolated coronary artery bypass grafting. They concluded that preoperative peptide levels > 502 ng/ml predict mid-term mortality after isolated coronary artery bypass grafting and are associated with significantly higher hospital mortality and perioperative complications. Reddy et al. [4] analyzed the sympathetic innervation of the internal thoracic artery to assess the effect of aging on this artery by histomorphometry using 54 human internal thoracic artery samples collected from 27 cadavers (19 male and 8 female) with ages of 19 to 83 years. Sympathetic nerve fibers are present in the adventitia of the internal thoracic artery. This is an elastic artery, although anatomically it is considered to be medium-sized. The sympathetic index may be used for analysis of sympathetic nerve fiber-related problems of the internal thoracic artery and may thus be used to gage the effects of aging thereupon. Nerbass et al. [5] evaluated whether massage therapy is an effective technique for improving sleep quality in patients following cardiopulmonary artery bypass graft surgery and conclude that it is an effective technique for improving patient recovery because it reduces fatigue and improves sleep. Hovnanian et al. [6] endeavored to determine long-term survival, identify preoperative factors predictive of a favorable outcome, and assess functional improvement after coronary artery bypass grafting in 244 patients with advanced left ventricular dysfunction. They claim that in selected patients with severe ischemic left ventricular dysfunction, the level of predominance of tissue viability, may be a tool capable of implementing preoperative clinical/functional parameters in predicting outcome as left ventricular ejection fraction and gated left ventricular ejection fraction at exercise/rest. Lima et al. [7] evaluated the influence of the Nursing Consultation Protocol in aspects of anxiety and depression in 78 patients after myocardial revascularization using the Hospital Anxiety and Depression scale (HAD), providing a sample of 39 patients in the control group (CG) and 39 in the intervention group (IG). It was found that people monitored in accordance with the Nursing Consultation Protocol had a lower percentage of anxiety and depression after six months. General cardiac surgical themes contribute 5 papers:

Armaganijan et al. [8] conducted a metanalytical survey of randomized trials of N-3 polyunsaturated fatty acid use for postoperative atrial fibrillation using the PUBMED CENTRAL, PUBMED, EMBASE, and LILACS databases. Four randomized studies (three double-blind, one openlabel) that enrolled 538 patients were identified. The patients were predominantly male, the mean age was 62.3 years, and most of the patients exhibited a normal left atrial size and ejection fraction. N-3 polyunsaturated fatty acid use was not associated with a reduction in postoperative atrial fibrillation. Similar results were observed when the openlabel study was excluded. They conclude that there is insufficient evidence to suggest that treatment with N-3 polyunsaturated fatty acids reduces postoperative atrial fibrillation. Therefore, their routine use in patients undergoing cardiac surgery is not recommended. Carneiro et al. [9] performed an exploratory, descriptive cohort study to verify the incidence of patients submitted to cardiac surgery who developed skin lesions during the intraoperative period, and to characterize these lesions. The total incidence was 21%. They observed that 19.2% of lesions were Pressure Ulcers (PU) in stage I; 1.1% of lesions were abrasive; 1.1% incisive; 0.5% lacerative; 0.5% superficial electrical burns; and 0.5% PU in stage II. Miranda et al. [10] analyzed the changes in vital signs of postoperative cardiac surgery patients, according to the referred pain intensity, through a descriptive-exploratory study performed in 38 patients submitted to a first dressing change. The analysis of the data, measured before and after performing the nursing procedure, indicated that the manifestation of pain occurred at different levels. The main changes in vital signs referred to blood pressure. In conclusion, there is a relationship between pain intensity and vital signs, and the care that is delivered is indispensible to reestablishing the health state of the postoperative patient. Torrati et al. [11] aimed to measure the sense of coherence and evaluate its association to sociodemographic variables and the use of psychotropic drugs among 127 patients in the preoperative period of cardiac surgeries. Their results suggest that female and young patients need more attention from nurses in the planning of their perioperative care. Hsu et al. [12] sought to study the associations of ambient noise with heart rate, blood pressure, and perceived psychological and physiological responses among 40 post-cardiac surgery patients in ICUs. The average noise level was between 59.0 and 60.8 dB(A) at the study site. Annoyance and insomnia were the respective psychological and physiological responses reported most often among the patients. Although noise level, irrespective of measures, was not observed to be significantly associated with the selfassessed psychological and physiological responses, it was significantly associated with both heart rate and blood 303


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pressure. They conclude that the noise in ICUs may adversely affect the heart rate and blood pressure of patients, which warrants the attention of hospital administrators and health care workers. Three other themes appeared important: Tedde et al. [13] compared bar displacement and complication rates in three retrospective series of patients for pectus excavatum operated on by the same surgical team. In the first series, the original, unmodified Nuss technique was performed, in the second, the ‘’third point fixation’’ technique was used, and in the last series, the correction was performed with modifications to the stabilizer and stabilizer position and found that elimination of fixation wires, the use of shorter bars and redesigned stabilizers placed in a more medial position results in a better outcome for pectus excavatum patients treated with the Nuss technique. Because bar displacement and instability are no longer significant postoperative risks, the Nuss technique should be considered among the available options for the surgical correction of pectus excavatum in pediatric patients. Yuan et al. [14] endeavored to elucidate the relationship between bicuspid aortic valve and aortic dilation A total of 241 bicuspid aortic valve patients were included in this study. In addition to the clinical characteristics of the included patients, the morphological features of the aortic valve and aorta, the length of the left main coronary artery, and the laboratory findings (the coagulation and hematological parameters as well as the total cholesterol concentration) were determined and compared with those of the tricuspid aortic valve patients. Bicuspid aortic valve patients developed aortic wall and aortic valve disorders at a younger age and were predominantly male. Aortic dilation was observed in the aortic root, sinotubular junction, and ascending aortic segments, in both the bicuspid and tricuspid aortic valve patients, although the bicuspid patients had a smaller degree of dilation, which was also significantly age-related in this group. Statin therapy did not affect the aortic annulus in either group, but did decrease the dimensions of the aortic root, sinotubular junction and ascending aorta. In general, statin therapy had a better effect on the aortas of the tricuspid than it did on those of the bicuspid patients. Abreu Filho et al. [15] evaluated the influence of the alloy and the profile of coronary stents on late loss and re-stenosis rates 6 months after implantation in 187 patients with multi-vessel coronary disease. At least one cobalt-chromium and one stainless steel stent were implanted per patient. They conclude that the use of two different alloys, stainless steel and cobaltchrome stents, in the same patient and in the same vessel produced similar 6-month re-stenosis and late loss rates. Three articles on Transplants were selected: Cinque & Bianchi [16] endeavored to identify the stressors experienced by family members during the process of organ

donation, evince the most distressful moment of the process and verify the association of variable with the family members’ experience. The sample consisted of 16 family members that were making the donation through an Organ Search Organization, in São Paulo, in 2007. They found that the donation process is sufficiently stressful on the family to make nursing care necessary in each stage of the process to offer support and reduce the distress on the family members. Guimarães et al. [17] evaluated the neurohormonal activity in heart transplant recipients and compared it with that in heart failure patients and healthy subjects during rest and just after a 6-minute walking test. During rest, norepinephrine was higher in heart transplant recipients and healthy subjects. Immediately after the 6minute walking test, the heart transplant and heart failure patients had higher norepinephrine levels than healthy subjects. Thus neurohormonal activity remains increased after the 6-minute walking test in heart transplantation recipients. Martino et al. [18] endeavored to determine if bone marrow mononuclear cell transplantation is safe for moderate to severe idiopathic dilated cardiomyopathy. Twenty four patients (age 46 ± 11.6 years, 17 males) with idiopathic dilated cardiomyopathy, with optimized therapy, NYHA classes II-IV, and left ventricular ejection fraction <35% were enrolled in the study. Clinical evaluation was performed at baseline and 6 months after stem cell therapy to assess heart function. They claim that their findings indicate that the transplantation therapy in these patients with severe ventricular dysfunction is feasible and that larger, randomized and placebo-controlled trials are warranted. Four articles on vascular surgery have been selected, Serrano et al. [19] endeavored to identify the functional results after aneurysm surgery in patients with ischemic cardiomyopathy and to determine predictors of favorable outcomes in 169 patients with angiographic left ventricular ejection fraction of 22 ± 5%, who underwent aneurysm surgery, and were prospectively followed for three years. Prior to surgery, 40% and 60% of the patients were in congestive heart failure NYHA class I/II and III/IV, respectively. Concomitant revascularization was performed on 95% of the patients and suggest that aneurysmectomy among patients with severe LV dysfunction result in short and long-term favorable functional outcome and survival. Selection of appropriate surgical candidates may substantially improve survival rates among these patients. Sincos et al. [20] retrospectively analyzed and compared the results of conventional surgical repair and endovascular treatment of blunt aortic injury in 26 patients treated for blunt aortic injury. Twenty-six patients were included in the study, 5 treated with operative repair and 21 with endovascular treatment and found that endovascular treatment was a safe method for repair of blunt aortic trauma,

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with immediate and midterm results that were comparable to those results obtained with operative repair. No complications from the stent graft were identified during follow-up. Nevertheless, long-term follow-up is necessary to confirm the effectiveness of this treatment. Morales et al. [21] performed a duplex ultrasound study to investigate morphological and hemodynamic patterns of carotid stenoses treated by endarterectomy with patch closure versus stenting in 29 carotid stenoses treated with stenting and 65 with patch closure. Measurements over time in luminal diameter signalized differences in arterial remodeling mechanisms between patched and stented carotids. Both stenting and patch closure were associated with carotid patency and flow restoration. This study does not support a general approach to new velocity criteria indiscriminately applied to stented or patched carotids. Orlando et al. [22] analyzed the results of treating deep venous malformations patients with low doses of ethanol in 39 patients treated between 1995 and 2007, followed up prospectively over a median period of 18 months. They conclude that outpatient treatment for deep venous malformations using ethanol at low doses was effective, with a low complication rate. An article on Lung surgery was frequently cited: TerraFilho et al. [23] evaluated the clinical and hemodynamic characteristics of 35 chronic thromboembolic pulmonary hypertension patients scheduled for pulmonary thromboendarterectomy in a referral center for chronic thromboembolic pulmonary hypertension treatment. They concluded that chronic thromboembolic pulmonary hypertension patients evaluated for pulmonary thromboendarterectomy had a hemodynamically severe status and elevated brain natriuretic peptide serum levels. On the theme of Hyperhydrosis, Wolosker et al. [24] assessed the quality of life of 1044 patients submitted to video-assisted thoracic sympathectomy for treating palmar hyperhydrosis according to gender and conclude that patients with palmar hyperhydrosis present an improvement in the quality of life after video-assisted thoracic sympathectomy regardless of gender. Dias et al. [25] examined the severity of trauma in 1203 motor vehicle accident entrapped vs. non-entrapped victims to identify risk factors for mortality and morbidity. Entrapped victims were predominantly men (84.8%), aged 32 Âą 13.1 years, with immediate mortality of 10.2% and overall mortality of 11.7%. They had a probability of death at the scene 8.2 times greater than that of non-entrapped victims. The main cause of death was hemorrhage for entrapped victims and trauma for non-entrapped victims. Thus entrapped victims had greater trauma severity, more blood loss, and a greater mortality than respective, non-entrapped controls. Clinical cardiology, pneumology and renal/cardiological articles contributed 22 entries, with the interaction of

exercise with heart function as the most frequent. Casonatto et al. [26] investigated in ten male subjects the effects of aerobic exercise with a cycle ergometer on the acute blood pressure response and to evaluate the indicators of autonomic activity after exercise. Authors did not find a reduction in blood pressure after exercise in normotensive, physically active young adults. However, the measurements of the indicators of autonomic neural activity revealed that in exercise of greater intensity the parasympathetic recovery tends to be slower and that sympathetic withdrawal can apparently compensate for this delay in recovery. Ciolac and Greve [27] compared the heart rate response to exercise and the exercise-induced improvements in muscle strength, cardiorespiratory fitness and heart rate response between normal-weight and overweight/obese postmenopausal women and conclude that overweight/obese women displayed impaired heart rate response to exercise. Both groups improved muscle strength, but only normal-weight women improved cardiorespiratory fitness and heart rate response to exercise. These results suggest that exerciseinduced improvements in cardiorespiratory fitness and heart rate response to exercise may be impaired in overweight/obese postmenopausal women. Farinatti et al. [28] evaluated heart rate, systolic blood pressure and ratepressure product of 22 asymptomatic volunteers during and after large and small muscle group flexibility exercises performed simultaneously with the Valsalva maneuver. They found that both the stretched muscle mass and the VM influence acute cardiovascular responses to multiple-set passive stretching exercise sessions. GalvĂŁo et al. [29] employed a murine model to investigate the effect of opioid receptor blockade on the myocardial protection conferred by chronic exercise and to compare exercise training with different strategies of myocardial protection (opioid infusion and brief periods of ischemia-reperfusion) preceding irreversible left anterior descending coronary ligation. They found that exercise training, morphine, exercise training plus morphine, and ischemia-reperfusion groups had a smaller infarct area than the control group. The effect of chronic exercise training in decreasing infarct size seems to occur, at least in part, through the opioid receptor stimulus, and not by increasing myocardial perfusion. Machado et al. [30] investigated the behavior of heart rate and heart rate variability during different loads of resistance exercise (incline bench press) in ten patients with coronary artery disease vs. ten healthy sedentary controls and conclude that loads up to 30% one-repetitionmaximum during incline bench press, result in depressed vagal modulation in both groups, although only the coronary artery disease patients presented sympathetic overactivity at 20% one-repetition-maximum upper limb exercise. Kanegusuku et al. [31] determined in 30 older adults whether different resistance training regimens, 305


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strength training (constant movement velocity) or power training (concentric phase performed as fast as possible) can blunt the increase in cardiovascular load during an aerobic stimulus and conclude that neither strength nor power training blunted submaximal or maximal heart rate, Systolic blood pressure or the rate-pressure product during the maximal exercise test, showing that they did not reduce cardiovascular stress during aerobic tasks. Mainenti et al. [32] investigated the effects of levothyroxine on cardiopulmonary exercise reserve and recovery in 23 women with subclinical hypothyroidism submitted to two ergospirometry tests, with an interval of 6 months of normalization of thyroid-stimulating hormone levels (levothyroxine replacement group) or simple observation. No relevant differences were observed in cardiopulmonary recovery for either group at baseline or after follow-up. In the sample studied, levothyroxine replacement improved exercise cardiopulmonary reserve, but no modification was found in recovery performance after exercise during this period of analysis. Martins-Pinge [33] focused on some groups of neurons involved in sympathetic regulation, including the nucleus tractus solitarii, caudal ventrolateral medulla and the rostral ventrolateral medulla that maintain and regulate the cardiac and vascular autonomic tonus. The results of these studies suggest that the beneficial effects of physical activity may be due, at least in part, to reductions in sympathetic nervous system activity. Conversely, with the recent association of physical inactivity with chronic disease, these data may also suggest that increases in sympathetic nervous system activity contribute to the increased incidence of cardiovascular diseases associated with a sedentary lifestyle. Oliveira et al. [34], in view of the fact that exercise oxygen pulse (O pulse), a surrogate for stroke volume and arteriovenous oxygen difference, has emerged as an important variable obtained during cardiopulmonary exercise testing hypothesized that the O pulse curve pattern response to a maximal cycling ramp protocol exhibits a stable linear pattern in subjects reevaluated under the same clinical conditions. Their findings show that, excluding the rest-exercise transition, the relative O pulse exhibited a stable linear increase throughout maximal exercise in adults that were retested under same clinical conditions. Peres et al. [35] analyzed the acute effect of submaximal exercise on aortic distensibility using pulse wave velocity and other hemodynamic variables in patients with Marfan Syndrome with either mild or no aortic dilatation. Pulse wave velocity and physiological variables were evaluated before and after submaximal exercise in 33 patients with Marfan Syndrome and in 18 healthy controls. Using comparative group analysis regarding PWV at rest and at the end of exercise they conclude that no statistically significant differences occurred. The same was true for the group that used beta-

blockers and the one that did not. The final heart rate and final systolic arterial pressure were higher in the control group vs. the Marfan Syndrome group, whereas pulse wave velocity did not differ between groups after submaximal effort. Perim el al. [36] analyzed the stability of the O2 pulse curve relative to body mass in elite athletes. VO2, heart rate (HR), and relative O2 pulse were compared at every 10% of the running time in two maximal cardiopulmonary exercise tests, repeated within a one-year interval, in 49 soccer players. They conclude that in young healthy men in good to excellent aerobic condition, the morphology of the relative O2 pulse curve is consistent up to close to the peak effort for a cardiopulmonary exercise testing repeated within a 1-year period. They also claim that no increase in relative O2 pulse at peak effort could represent a physiologic stroke volume limitation in these athletes. Diagnosis is the second most frequent entry. Gimenes et al. [37] determined the response characteristics and functional correlates of the dynamic relationship between the rate (Ă„) of oxygen consumption (VO2) and the applied power output (work rate = WR) during ramp-incremental exercise in 14 patients with mitochondrial myopathy vs. 10 sedentary controls. They claim that a readily available, effort-independent index of aerobic dysfunction during dynamic exercise is typically reduced in patients with mitochondrial myopathy, being related to increased functional impairment and higher cardiopulmonary stress. Martins et al. [38] investigated high-sensitivity C-reactive protein levels as predictors of acute myocardial infarction risk in 101patients undergoing high-risk noncardiac surgery and found that such patients especially vascular surgery patients presenting elevated baseline high-sensitivity Creactive protein levels are at increased risk for perioperative acute myocardial infarction. Myers et al. [39] examined the association between cardiac performance during recovery and the severity of heart failure, as determined by clinical and cardiopulmonary exercise test responses. They find that impaired cardiac output recovery kinetics can identify heart failure patients with more severe disease, lower exercise capacity, and inefficient ventilation. Estimating cardiac output in recovery from exercise may provide added insight into the cardiovascular status of patients with heart failure. They conclude that in this heterogeneous study population, stress cardiomyopathy presented with a 3:2 female-to-male ratio, and dyspnea was the most common chief complaint. Stress cardiomyopathy exhibited a T wave inversion as the primary EKG abnormality. These findings differ from previously reported data, and the authors conclude that further studies are needed. Rosoky et al. [40] investigated whether oxidized low-density lipoprotein is a suitable predictor of peripheral arterial disease severity in 85 consecutive patients with an ankle-brachial pressure index (ABPI) < 0.9 and the presence of either intermittent

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claudication or critical lower leg ischemia and conclude that oxidized low-density lipoprotein is not a good predictor of peripheral arterial disease severity. Simsek et al. [41] evaluated P wave dispersion in patients with iron deficiency anemia and the possible relationships between P wave dispersion and other echocardiographic parameters in 97 patients who had iron deficiency anemia and 50 healthy subjects. They conclude that iron deficiency anemia may be associated with prolonged P wave duration and dispersion and impaired diastolic left ventricular filling. Yuksel et al. [42] aimed to retrospectively investigate the relationship between admission levels of serum yglutamyltransferase and poor myocardial perfusion after primary percutaneous coronary intervention in patients with acute myocardial infarction in 80 patients with thrombolysis in myocardial infarction grades 0/1 flow preprocedurally. The patients were divided into two groups according to thrombolysis in myocardial perfusion grades that were assessed immediately following primary percutaneous coronary intervention. The two groups (group 1 and group 2) each consisted of 40 patients with thrombolysis in myocardial perfusion grades 0-1 and thrombolysis in myocardial perfusion grades 2-3, respectively and found that high admission ĂŁglutamyltransferase levels are associated with poor myocardial perfusion in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention, particularly in patients with prolonged pain to balloon time. Two papers cover Hypertension: de Souza Nery et al. [43] describe blood pressure responses during resistance exercise in ten hypertensive vs. ten normotensive subjects to determine whether an exercise protocol alters these responses and found that resistance exercise increased systolic blood pressure considerably more in hypertensives than in normotensives, and this increase was greater when lower-intensity exercise was performed to the point of exhaustion. Medeiros et al. [44] investigated the hemodynamic responses to mental stress before and after a bout of exercise in subjects with prehypertension and found that such patients exhibited elevated blood pressure and a blunted vasodilator response during mental stress, but their blood pressure was attenuated and their vasodilator response was normalized after a single bout of maximal dynamic exercise. The theme of Heart failure is introduced by Correale et al. [45] who retrospectively analyzed 353 consecutive outpatients with chronic heart failure (mean follow-up 384 days), based on whether or not statin therapy was used. In all patients, several Tissue Doppler Imaging parameters were measured; circulating levels of interleukin IL-6, IL-10 and C-reactive protein were also assayed. They conclude that chronic ischemic heart failure outpatients undergoing

statin treatment had fewer readmissions for adverse events, blunted inflammatory activation, and improved left ventricular performance assessed by Tissue Doppler Imaging. Two articles cover the Renal/Cardiological interaction: Duran et al. [46] analyzed the effect of maintenance hemodialysis on left ventricular diastolic function in 42 patients with end-stage renal disease and found that disease treatment in these patients with hemodialysis via arteriovenous fistulae induce a variety of hemodynamic and metabolic abnormalities that predispose to alterations in left and right ventricular functions. They claim that left ventricular diastolic function and right ventricular functions were not significantly changed, but that left ventricular systolic functions were impaired after maintenance hemodialysis treatment in these patients. Girardi et al. [47] assessed the effects of rosuvastatin on renal injury and inflammation in a murine model of nitric oxide deficiency and found that rosuvastatin treatment reduced glomerular damage due to improvement in the inflammatory pattern independent of the systolic blood pressure and serum lipid level. These effects may lead to improvements in the treatment of kidney disease. The basic science themes of Pathology, Physiology and Molecular Biology are covered in 9 articles, 6 cardiac, 2 pulmonary, and one renal: Carneiro-JĂşnior et al. [48] determined the effects of exercise training and detraining on the morphological and mechanical properties of left ventricular myocytes in 4-month-old spontaneously hypertensive rats (SHR) randomly divided into sedentary for 8 weeks, sedentary for 12 weeks, treadmill-running trained for 8 weeks (TRA, 16 m/min, 60 min/day, 5 days/ week), and treadmill-running trained for 8 weeks followed by 4 weeks of detraining. Cell length was greater in TRA than in SED-8 and remained larger after detraining. Cell width and volume were unaffected by either exercise training or detraining. Exercise training did not affect cell shortening, which was unchanged with detraining. TRA cells exhibited higher maximum velocity of shortening than SED-8 with almost complete regression after detraining. They conclude that exercise training affected left ventricle remodeling in SHR towards eccentric hypertrophy, which remained after detraining. It also improved single left ventricular myocyte contractile function, which was reversed by detraining. Piratello et al. [49] evaluated the role of angiotensin I, II and 1-7 on left ventricular hypertrophy of Wistar and spontaneously hypertensive rats submitted to sinoaortic denervation and conclude that not only blood pressure variability and reduced baroreflex sensitivity but also elevated levels of angiotensin II and a reduced concentration of angiotensin 1-7 may contribute to the development of left ventricular hypertrophy. These data indicate that baroreflex dysfunction associated with 307


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changes in the renin angiotensin system may be predictive factors of left ventricular hypertrophy and cardiac failure. Roque et al. [50] investigated the effects of swimming training on coronary blood flow, adenosine production and cardiac capillaries in normotensive rats and found that swimming training increases coronary blood flow, number of cardiac capillaries, and adenine nucleotide hydrolysis. Increased adenosine production may be an important contributor to the enhanced coronary blood flow and angiogenesis that were observed in the exercise-trained rats; collectively, these results suggest improved myocardial perfusion. Soares et al. [51] examined the effect of exercise training without or with a 3% workload on different cardiac and renal parameters in renovascular hypertensive (2K1C) male Fisher rats weighing 150-200 g. Morphometric evaluation showed concentric left ventricle hypertrophy in sedentary rats. Unloaded exercise prevented concentric cardiac hypertrophy, increased cardiomyocyte diameter and decreased cardiac vasculature thickness. In contrast, 3% loaded exercise reduced concentric remodeling and prevented the increase in cardiac vasculature wall thickness, decreased the cardiomyocyte diameter and increased collagen deposition. Renal morphometric analysis showed that Ex 3% induced an increase in vasculature wall thickness and collagen deposition in the left kidney of 2K1C rats. These data suggest that unloaded exercise has more beneficial effects than the loaded modality. Valenti et al. [52] compared baroreflex sensitivity among a subset of normotensive Wistar Kyoto rats which show lower baroreflex sensitivity and found that approximately 37% of the rats showed a reduced bradycardic peak, bradycardic reflex and decreased bradycardic gain of baroreflex while roughly 23% had a decreased basal HR, tachycardic peak, tachycardic reflex and reduced sympathetic baroreflex gain. No significant alterations were noted with regard to basal MAP. They conclude that there is variability regarding baroreflex sensitivity among Wistar Kyoto rats from the same laboratory. Veiga et al. [53] investigated whether previous exercise training could prevent or attenuate acute cardiac alterations after myocardial infarction in female rats submitted to swim training or allowed to remain sedentary for 8 weeks. They were randomly assigned to left coronary artery occlusion or sham surgery and found that previous swim training does not attenuate systolic and diastolic function alterations after myocardial infarction induced by left coronary artery occlusion, suggesting that cardioprotection cannot be provided by exercise training in this experimental model. Capelozzi et al. [54] performed a histopathological analysis of the open lung biopsy specimens from five patients with ARDS with confirmed H1N1 and claim that viral-like particles can be successfully demonstrated in lung tissue by ultrastructural examination, without confirmation of the virus by RT-PCR on

nasopharyngeal aspirates. Bronchioles and epithelium, rather than endothelium, are probably the primary target of infection, and diffuse alveolar damage the consequence of the effect of airways obliteration and dysfunction on innate immunity, suggesting that treatment should be focused on epithelial repair. Valenti et al. [55] evaluated the effects of central catalase inhibition on cardiopulmonary reflex in conscious Wistar rats and concluded that increased sympathetic inhibition does not change the parasympathetic component of the cardiopulmonary reflex in these conscious animals. Garcia-Pinto et al. [56] endeavored to observe the beneficial effects of lowintensity physical activity on structural and ultrastructural renal morphology and blood pressure in normotensive and spontaneously hypertensive rats. They found that exercised, spontaneously hypertensive rats showed a significant blood pressure reduction of 26%. The body masses of the Wistar-Kyoto and spontaneously hypertensive strains were significantly different. There were improvements in some of the renal structures of the animals treated with physical activity. The spontaneously hypertensive rats also showed a decreased expression of connexin-43. They conclude that physical exercise could be a therapeutic tool for improving kidney ultrastructure and, consequently, renal function in hypertensive individuals. Anesthesiology for thoracic surgery contributes 3 original research themes: Basagan-Mogol et al. [57] evaluated the hemodynamic and analgesic effects of ketamine by prospectively comparing it with propofol starting at the induction of anesthesia until the end of sternotomy in 30 patients undergoing coronary artery bypass grafting surgery. There were no differences between groups in the consumption of sevoflurane or in the use of additional fentanyl. The combination of ketamine, midazolam, and fentanyl for the induction of anesthesia provided better hemodynamic stability during induction and until the end of sternotomy in patients undergoing coronary artery bypass grafting surgery. Hajjar et al. [58] evaluated whether arterial lactate or standard base deficit on admission and after 24 hours can predict mortality for patients with cancer. They evaluated 1,129 patients with severe sepsis, septic shock, or postoperative after highrisk surgery. Lactate and standard base deficit collected at admission and after 24 hours were compared between survivors and non-survivors. Their findings suggest that lactate and standard base deficit measurement should be included in the routine assessment of patients with cancer admitted to the intensive care unit with sepsis, septic shock or after high-risk surgery. These markers may be useful in the adequate allocation of resources in this population. Ornek et al. [59] investigated the effects of sevoflurane general anesthesia vs. bupivacaine selective spinal

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anesthesia on electrocardiographic QT dispersion and corrected QT interval though a prospective, randomized, double-blind study conducted on 40 patients undergoing noncardiac surgery randomized into two groups. They conclude that although Volatile Induction and Maintenance of Anesthesia with sevoflurane might prolong the QT corrected interval with no resulting arrhythmia, selective spinal anesthesia with bupivacaine was not associated with alterations in the QT interval or arrhythmia.

10. Miranda AF, da Silva LF, Caetano JA, de Sousa AC, Almeida PC. [Evaluation of pain intensity and vital signs in the cardiac surgery postoperative period]. Rev Esc Enferm USP. 2011;45(2):327-33.

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REVIEW ARTICLE

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Conservative surgical management of mitral insufficiency: an alternative approach Tratamento cirúrgico conservador da insuficiência mitral: uma abordagem alternativa

Francisco Gregori Junior1 DOI: 10.5935/1678-9741.20120049

RBCCV 44205-1386

Abstract Mitral valve insufficiency is frequently the result of elongated or ruptured chordae tendineae. Several techniques have been described for its correction. However, when there is a severe elongation or rupture of the chordae, the most widely accepted treatment option has been valve replacement. The best long-term outcomes observed in conservative surgeries led us to choose this procedure rather than the correction of mitral valve insufficiency. We described three techniques for correction of mitral prolapse due to elongated and/or ruptured chordae. In addition, we developed mold pre built bovine pericardial chords (BraileGregori Prosthesis) for chordae replacement. Finally, since 1987, the rigid prosthetic semicircular ring (Gregori-Braile Ring) has been consistently used in our Centre for correction of the posterior dilation of mitral annulus preferably in its portion close to the posteromedial commissure.

Resumo A insuficiência mitral é frequentemente resultado do alongamento ou ruptura das cordas tendíneas. Várias técnicas foram descritas para sua correção. Entretanto, quando o comprometimento das cordas é mais intenso, a substituição valvar tem sido mais usualmente empregada. Os bons resultados a longo prazo observados na cirurgia conservadora têm nos levado a eleger esse procedimento como prioridade. Três técnicas foram por nós desenvolvidas para correção de alongamento e/ou ruptura de cordas tendíneas. Além disso, desenvolvemos uma prótese de pericárdio bovino para a substituição de cordas (prótese Braile-Gregori). Finalmente, desde 1987 empregamos o anel rígido semicircular (anel GregoriBraile) para a correção do alongamento posterior do anel mitral, com ênfase na sua porção junto à comissura póstero-medial.

Descriptors: Mitral valve insufficiency. Conservative management. Alternative techniques.

Descritores: Valva mitral/cirurgia. Insuficiência da valva mitral.

INTRODUCTION Conservative management of mitral insufficiency is an alternative technique with attractive features [1-5]. Among the many advocates of valve repair, Alain Carpentier is the best-known [6]. His techniques include a combination of ring annuloplasty, resection of segments of valve leaflets, and shortening, transposition and sectioning of chordae. However, despite this repertoire of repair maneuvers, 1. Head Professor. Cardiac Surgery Division, University of Londrina - Paraná School of Medicine, Londrina, SP, Brazil.

This study was carried out at the Cardiac Surgery Division, University of Londrina - Paraná School of Medicine, Londrina, SP, Brazil.

replacement of the mitral valve is the most common method used for patients with mitral insufficiency. Mitral insufficiency, defined as blood regurgitation from the left ventricle to the left atrium through the valve, is a situation predisposing to left ventricular dysfunction, increase of the left atrium, and atrial arrhythmias, regardless of the etiology. Mitral insufficiency is a common feature in rheumatic disease and fibroelastic degeneration. Mitral valve prolapse identified by redundancy of the anterior Correspondence address: Francisco Gregori Junior Rua Paes Leme, 1264 – Sala 701 Londrina, PR, Brazil – CEP 86010-520 E-mail: circardiaca@sercomtel.com.br Article received on April 12th, 2012 Article accepted on June 6th, 2012

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and/or posterior leaflet, papillary muscle dysfunction, and chordae tendineae elongation or rupture may evolve to mitral insufficiency. Mitral valvuloplasty is an elective procedure for repair of mitral insufficiency, with better results than mitral valve replacement [7]. We have employed mitral reconstructive surgery in our Service since 1979, according to Carpentier techniques. We introduced new alternative techniques that have been used in parallel to those traditional procedures. REPAIR OF ELONGATED CHORDAE TENDINEAE In 1989, we introduced a new technique for shortening of elongated chordae tendineae [8]. It is particularly suitable for shortening the chordae tendineae in patients in whom the papillary muscles are either thin or deeper than usual. The shortening performed above the anterior leaflet of the mitral valve is quite feasible because of the accessible surgical site and easy quantification of the elongation of the chordae tendineae to be corrected. Once the elongated chordae is identified, the anterior leaflet is exposed and an orifice about two to three millimeters wide is made at the insertion of the elongated chordae (Figure 1). After that procedure, the elongated chordae is pulled through the orifice with a nerve tractor or even a thick cotton thread, so that the anterior leaflet is towered to an appropriate level, resulting in a satisfactory coaptation of the leaflets. The orifice is sutured with interrupted 5-0 polypropylene sutures. The sutures also fasten the chordae to the atrial surface of the anterior leaflet of the mitral valve.

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REPAIR OF RUPTURED CHORDAE TENDINEAE 1. Neo chordae construction [9] The mitral valve is carefully evaluated and the ruptured or “missing” chordae of the anterior leaflet are located precisely and marked with a suture. Two parallel incisions are made about five to 12 millimeters apart. The incisions begin at or near the annulus and carried toward the reference suture up to a point five millimeters from the free border of the leaflet. This strip of tissue thus created is detached. The detachment begins near the annulus and is tucked through the slit under the free border, whichever is easier, and brought toward the ventricular cavity. Then, the anterior leaflet is repaired with interrupted 5-0 polypropylene sutures. Next, the strip is sutured to the anterior papillary muscle with 5-0 polypropylene mattress sutures. (Figure 2).

Fig 2 – Left: the strip of tissue is tucked through the slit under the edge of the leaflet. Right: the opening in the prior leaflet is repaired with interrupted 5-0 polypropylene suture, and the neo chorda is sutured to the anterior papillary muscle with 5-0 mattress sutures

Fig. 1 – Left: schematic illustration shows the elongated chordae. Right: note that the orifice (2 to 3 millimeters wide) is near the edge of the leaflet, at a site corresponding to the insertion site of the elongated chordae. Traction of an elongated chordae through the orifice in the anterior leaflet is observed. The orifice in the anterior leaflet is sutured with interrupted 5-0 polypropylene sutures. Lower: the chordae tendineae are fastened to the atrial surface of the mitral valve

2. Partial tricuspid valve transfer [10] Supply of chordae for the anterior leaflet of the mitral valve proceeds according to two techniques. The first and more frequent technique consists of removing the entire posterior leaflet of the tricuspid valve (with all its elements), I.E., chordae and papillary muscle (Figure 3). The specimen is transferred to the mitral valve by suturing the papillary muscle to that of the mitral valve, corresponding to the ruptured chordae, using one stitch in U anchored on small Dacron pledgets. After attaching the papillary muscle, the donor leaflet is sutured to the anterior leaflet of the mitral valve avoiding extensive chordae that would cause leaflet to prolapse and consequent mitral insufficiency. The same care must be taken regarding the opposite, I.E., chordae retraction with unwanted coaptation of the anterior leaflet 313


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causing mitral insufficiency (Figure 4). The grafted leaflet may be sectioned in the middle. Two heads must remain linked to the papillary muscle by a good number of chordae. One of these heads is sutured to the anterior leaflet and the other to the posterior on (Figure 5). The tricuspid annulus is plicated with 4-0 polypropylene sutures. It is anchored on Dacron pledgets at the posterior portion leaving the bicuspid valve, furthermore, correcting any eventual functional tricuspid insufficiency. The second technique (Figure 6), a variant of the first one, is applied when the posterior leaflet of the tricuspid valve or even the corresponding papillary muscle is not anatomically adequate. In these cases, the anterior valve is always more developed to compensate for the small posterior leaflet. Thus, a triangular patch is removed from the anterior leaflet with a satisfactory number and texture of chordae and a wedge of the corresponding papillary muscle, which is transferred to the mitral valve and sutured

afterwards, in the same way to the abovementioned technique. The tricuspid valve in these cases remains with its three leaflets. The sectioned edges of the anterior leaflet are joined with separated 5-0 polypropylene stitches.

Fig. 5 – The graft sectioned in the middle remaining with two heads linked to the papillary muscle by a good number of chordae. One head is sutured to the anterior leaflet and the other head to the posterior on

Fig. 3 – Removal of the posterior leaflet of the tricuspid valve, rendering it bicuspid. The specimen (lower) containing the leaflet, chordae tendineae, and the papillary muscle will be transferred to the mitral valve Fig. 6 – Left: a triangular patch is removed from the anterior leaflet of the tricuspid valve, with a satisfactory number and texture of chordae and a wedge of the papillary muscle which is transferred to the mitral valve. Right: sectioned edges of the anterior leaflet is joined with separated 5-0 polypropylene stitches

3. Repair of ruptured chordae or thin elongated chordae by premolded bovine pericardium chords [11]

Fig. 4 – Intraoperative aspect after suture of the graft on the papillary muscle and the anterior leaflet of the mitral valve

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The Braile-Gregori Prosthesis The Braile-Gregori Prosthesis [11] created for repair of ruptured chordae is fashioned as a monobloc (Braile Biomédica Industria, Comércio e Representações S/A® – São Paulo – Brazil) joined at their extremities by two polyester-reinforced strips. The standardized bovine pericardium chordae were two millimeters wide and three


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millimeters distant from each other (Figures 7A and B) Standardization of the chordae is confirmed by using measuring instruments ranging in length from 20 to 35 millimeters (Figure 8). The bovine pericardium is treated with 0.5% glutaraldehyde and then submitted to anticalcification treatment with glutamic acid. Next, it is preserved in 4% formaldehyde solution. Rupture levels of nearly 15 kg/cm 3 were found during resistance and durability tests [13]. The chordae length is determined based on the distance from the top of the papillary muscle to the edge of the leaflet in its original non-prolapsed position.

Fig. 8 – Measuring instruments ranging in length from 20 to 35 mm are used to confirm standardization of the chordae

0 polypropylene sutures to the free edge of the affected leaflet (Figure 9). The prosthesis with five standardized chordae may be reduced to as few as two chordae, as required. III – MITRAL ANNULOPLASTY (GREGORI-BRAILE RING) [12] Since the introduction of open valve surgery, annular dilation found in all cases of mitral insufficiency has been treated conservatively. Almost simultaneously, many centers started correcting mitral insufficiency using plication mitral annuloplasty. This surgical procedure is a daily basis practice. After having observed anatomic alterations in patients with mitral insufficiency, Carpentier et al. [6] described several techniques for the correction of mitral insufficiency including annuloplasty with a prosthetic ring. Since then, several centres worldwide have adopted

Fig. 7 – A and B: standardized bovine pericardium chordae

Prosthesis Implant The implant procedure began by anchoring the prosthesis on the top end of the papillary muscle associated with the ruptured chordae using one or two 5-0 polypropylene threads anchored in a Dacron pad. Subsequently, the other end is attached using individual 5-

Fig. 9 – Anatomical aspect of the implantation of the prosthesis in an open bovine left ventricle

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his techniques with excellent results. From 1979 to 1986, we operated on more than 100 patients using Carpentier ring annuloplasty. One-third of the patients were under the age of 16. Dilation of the anterior side of the mitral annulus between the two fibrous trigonae was demonstrated by Hueb et al. [14]. However, it was frequently found posteriorly and to a greater extent posteriorly and next to the posteromedial commissure (Figure 10). Based on these findings, we developed a rigid prosthetic semicircular ring (stainless steel wrapped in a thin layer of silicon rubber and covered with Dacron velvet) (Figures 11 and 12). By making fine adjustment on its right side, we could correct the dilation of the posterior side of the mitral ring next to the posteromedial commissure. The prosthesis corrects the annular dilation (Figure 13) and avoids the late manifestation of mitral stenosis in children and young patients, which is secondary to restraining the normal growth of the mitral ring. It is observed when closed prosthetic rings are used.

Fig. 10 – A: normal mitral valve annulus. B: posterior dilation of the annulus and to a greater extent next to the posteromedial commissure (arrows)

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Fig. 12 – Schematic drawing showing the implantation of the Gregori-Braile ring prosthesis. Below the Gregori-Braile ring prosthesis

Fig. 13 – Intraoperative surgical aspect of a mitral annuloplasty by the Gregori-Braile ring prosthesis

DISCUSSION

Fig. 11 – Technical drawing. The assembly of the prosthetic semicircular ring. Left: measurements of the largest diameter (in millimeters) in A. Right: attention to the rectification on the right that will correct the posterior dilation of the mitral annulus which is greater next to the posteromedial commissure

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The prosthetic ring presented here was first used in our centre in October, in 1987 [12]. Since then, this prosthesis has been employed in more than 40 centres in Brazil and other countries. It was developed to correct the dilation of the posterior mitral annulus, which resulted in a semicircular shape. In our opinion, the anterior part of the closedring prosthesis is not only dispensable but also inconvenient in some situations. The posterior ring annuloplasty concept has been adopted by many surgeons as described by Hendren et al. [15], Salvador et al. [16] and Salati et al. [17] who used bovine pericardium strips fixed by glutaraldehyde. Braile et al. [13] who used berets – also made of a bovine pericardium. The mitral valvular system, including the mitral ring grows and develops in children. Implant of an open prosthesis in children with mitral insufficiency allows for normal growth of the anterior leaflet,


Gregori Junior F - Conservative surgical management of mitral insufficiency: an alternative approach

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which corresponds to the distance between the fibrous trigonae. Any millimeter growth in this area may avoid the late manifestation of mitral stenosis, which happens when closed rings are used in small children. Our own comparative studies in adults have demonstrated the presence of a mitral transvalvar pressure gradient of smaller magnitude in patients with this prosthesis when compared to patients who had the closed ring implanted. The adjustment on the right side of the prosthetic ring was introduced for the correction of small leakage. It is frequently found next to the posteromedial commissure since this is the portion of the mitral ring with greater dilation. If required, once the Gregori-Braile ring is implanted, the intervention into the subvalvar system is made easily, which includes the shortening of elongated chordae tendineae and sectioning of retractable chordae. The results have been consistent both in adults and children. Machado & Gregori [18] showed the late evaluation of rheumatic children under the age of 12 undergoing reconstructive mitral valve surgery with implant of the Gregori-Braile ring. After 188 months, the survival rate was 82% and the annual mortality rate 0.38%. Thirty-one (72.6%) patients did not require reoperation and the annual rate of patients who required further surgery was 0.51%.

6. Carpentier A, Relland J, Deloche A, Fabiani JN, D'Allaines C, Blondeau P, et al. Conservative management of the prolapsed mitral valve. Ann Thorac Surg. 1978;26(4):294-302.

REFERENCES 1. Souza LR, Brandão CMA, Pomerantzeff PMA, Leite Filho OA, Cardoso LF, Stolf NAG. Evolução tardia da comissurotomia mitral em pacientes reumáticos com baixo escore ecocardiográfico. Rev Bras Cir Cardiovasc. 2011;26(3):380-5. 2. Tenório EM, Moraes Neto F, Chauvaud S, Moraes CRR. Experiência com a técnica de ampliação do folheto posterior para correção da insuficiência mitral reumática na infância. Rev Bras Cir Cardiovasc. 2009;24(4):567-9. 3. Severino ESBO, Petrucci O, Vilarinho KAS, Lavagnoli CFR, Silveira Filho LM, Oliveira PPM, et al. Resultados tardios da plastia mitral em pacientes reumáticos. Rev Bras Cir Cardiovasc. 2011;26(4):559-64. 4. Guedes MAV, Pomerantzeff PMA, Brandão CMA, Vieira MLC, Leite Filho OA, Silva MF, et al. Plastia valvar mitral pela técnica do duplo teflon: análise do remodelamento cardíaco pela ecocardiografia tridimensional. Rev Bras Cir Cardiovasc. 2010;25(4):534-42. 5. Pomerantzeff PMA, Brandão CMA, Leite Filho OA, Guedes MAV, Silva MF, Grinberg M, et al. Plástica da valva mitral em pacientes com insuficiência mitral reumática: técnicas e resultados de 20 anos. Rev Bras Cir Cardiovasc. 2009;24(4):485-9.

7. Akins CW, Hilgenberg AD, Buckley MJ, Vlahakes GJ, Torchiana DF, Daggett WM, et al. Mitral valve reconstruction versus replacement for degenerative or ischemic mitral regurgitation. Ann Thorac Surg. 1994;58(3):668-75. 8. Gregori Júnior F, Silva S, Façanha L, Cordeiro C, Aquino W, Moure O. Preliminary results with a new technique for repairing elongated chordae tendineae of the anterior mitral valve leaflet. J Thorac Cardiovasc Surg. 1994;107(1):321-3. 9. Gregori F Jr, Takeda R, Silva S, Façanha L, Meier MA. A new technique for repair of mitral insufficiency caused by ruptured chordae of the anterior leaflet. J Thorac Cardiovasc Surg. 1988;96(5):765-8. 10. Gregori F Jr, Cordeiro CO, Croti UA, Hayashi SS, Silva SS, Gregori TE. Partial tricuspid valve transfer for repair of mitral insufficiency due to ruptured chordae tendineae. Ann Thorac Surg. 1999;68(5):1686-91. 11. Gregori F Jr, Leal JC, Braile DM. Premolded bovine pericardial chords for replacement of ruptured or elongated chordae tendineae. Heart Surg Forum. 2010;13(1):E17-20. 12. Gregori F, Silva SS, Hayashi SS, Aquino W, Cordeiro C, Silva LR. Mitral valvuloplasty with a new prosthetic ring. Analysis of the first 105 cases. Eur J Cardiothorac Surg. 1994;8(4):168-72. 13. Braile DM, Ardito RV, Pinto GH, Santos JLV, Zaiantchick M, Souza DRS, et al. Plastia mitral. Rev Bras Cir Cardiovasc. 1990;5(2):86-98. 14. Hueb AC, Jatene FB, Moreira LF, Pomerantzeff PM, Kallás E, Oliveira SA. Ventricular remodeling and mitral valve modifications in dilated cardiomyopathy: new insights from anatomic study. J Thorac Cardiovasc Surg. 2002;124(6):1216-24. 15. Hendren WG, Nemec JJ, Lytle BW, Loop FD, Taylor PC, Stewart RW, et al. Mitral valve repair for ischemic mitral insufficiency. Ann Thorac Surg. 1991;52(6):1246-51. 16. Salvador L, Rocco F, Ius P, Tamari W, Masat M, Paccagnella A. The pericardium reinforced suture annuloplasty: another tool avaiable for mitral annulus repair? J Card Surg. 1993;8(1):79-84. 17. Salati M, Scrofani R, Santoli C. Posterior pericardial annuloplasty: a physiological correction? Eur J Cardiothorac Surg. 1991;5(5):226-9. 18. Machado VH, Gregori Júnior F. Late heart evaluation of children with rheumatic mitral regurgitation submitted to reconstructive surgery with implantation of Gregori’s ring. Arq Bras Cardiol. 2005;85(6):403-11.

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SPECIAL ARTICLE

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Greek language: analysis of the cardiologic anatomical etymology: past and present Idioma grego: análise da etimologia anatomocardiológica: passado e presente

Georges Bezas1, Alexandre Lins Werneck2 DOI: 10.5935/1678-9741.20120050

RBCCV 44205-1387

Abstract Introduction: The Greek language, the root of most Latin anatomical terms, is deeply present in the Anatomical Terminology. Many studies seek to analyze etymologically the terms stemming from the Greek words. In most of these studies, the terms appear defined according to the etymological understanding of the respective authors at the time of its creation. Therefore, it is possible that the terms currently used are not consistent with its origin in ancient Greek words. Methods: We selected cardiologic anatomical terms derived from Greek words, which are included in the International Anatomical Terminology. We performed an etymological analysis using the Greek roots present in the earliest terms. We compared the cardiologic anatomical terms currently used in Greece and Brazil to the Greek roots originating from the ancient Greek language. We used morphological decomposition of Greek roots, prefixes, and suffixes. We also verified their use on the same lexicons and texts from the ancient Greek language. Results: We provided a list comprising 30 cardiologic anatomical terms that have their origins in ancient Greek as well as their component parts in the International Anatomical Terminology. We included the terms in the way they were standardized in Portuguese, English, and Modern Greek as well as the roots of the ancient Greek words that originated them. Conclusion: Many works deal with the true origin of words (etymology) but most of them neither returns to the

earliest roots nor relate them to their use in texts of ancient Greek language. By comparing the world’s greatest studies on the etymology of Greek words, this paper tries to clarify the differences between the true origin of the Greek anatomical terms as well as the origins of the cardiologic anatomical terms more accepted today in Brazil by health professionals.

1. Majored in Physical Education at the Aristoteles University of Thessaloniki; Exercise Physiology Specialist; São José do Rio Preto Medical School (FAMERP), São José do Rio Preto, SP, Brazil.

Correspondence address: Georges Bezas Rua do Rosário, 1810 - São José do Rio Preto, SP, Brazil – Zip Code 15030-560 E-mail: gbezas23@hotmail.com Article received on April 4th , 2012 Article accepted on June 28 th , 2012

2. Doctor of Health Science (DHSc), São José do Rio Preto Medical School (FAMERP), São José do Rio Preto, SP, Brazil.

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Keywords: Etymology. Terminology as topic. Cardiology.

Resumo Introdução: O idioma grego, base para a criação do idioma latino, está muito presente na terminologia anatômica. Muitos trabalhos buscam analisar etimologicamente os termos provindos do idioma grego. Na maioria destes, os termos aparecem definidos conforme o entendimento etimológico dos respectivos autores da época de sua criação. Portanto, é possível que os termos atualmente utilizados não estejam condizentes com sua origem no idioma grego antigo. Métodos: Foram selecionados termos anatomocardiológicos derivados do idioma grego que constam da terminologia anatômica internacional. A análise etimológica foi realizada por meio dos radicais mais primitivos que compõem os termos. Os termos anatomocardiológicos atualmente utilizados na Grécia e no Brasil foram comparados aos radicais originários do idioma grego antigo. Utilizou-se a decomposição morfológica dos radicais, prefixos e sufixos e verificou-se o emprego dos mesmos em léxicos e textos do idioma grego antigo.


Bezas G & Werneck AL - Greek language: analysis of the cardiologic anatomical etymology: past and present

Abbreviations, acronyms & symbols B.C. G.L. A.G.L. M.G.L. NA PNA

Before Christ Greek Language Ancient Greek Language Modern Greek Language Nomina Anatomica Parisiensia Nomina Anatomica

Resultados: Foi feita uma lista com 30 termos anatomocardiológicos derivados do idioma grego e componentes da terminologia anatômica internacional. Os termos constam na forma que foram padronizados no Brasil,

INTRODUCTION Anatomy is the area of medical science that deals with the structure, arrangement and function of human organs, as well as the dissection of the body with the aim of studying its various parts. Anatomy designates all parts of the human body for teaching purposes. It is an independent branch of medical science, and it is essential for understanding the clinical facts. Heart anatomy, or cardiac anatomy, is used to designate the terms related to the anatomy of the heart. The word analysis comes from the Greek. Since Ancient Greece, it means “examination and study of a situation or an object in terms of the parts composing its simplest elements. It has the purpose of addressing and clarifying the situation or object through the breaking up of a whole into smaller parts” [1]. Etymology is the study the origin of the words. It studies the sources (roots) of words going back to the words that originated them [2]. The Greek Language (GL), the basis for the creation of the Latin language [3], is much present in coining terms of anatomy. The spoken language of Greece comes from a prehistoric language, the Indo-European language, which is actually a hypothetical language supported only by poorly documented evidence [3]. This language appears in a given period of the Ancient History when people coming from India join others who were already living in parts of Europe. Historically, it is concluded that, with the experience of living in society these people have developed close ties and also an almost common language [3,4]. The differentiations and peculiarities of the Greek language, however, began to develop soon after the dissociation of the Greek people (the Hellenos) from the other IndoEuropean peoples. This probably occurred during the third millennium BC. At least, 2000 years B.C., the Greeks were already living in their territory, which they called Elláda [3,4], known in Brazil as the Hellenic Republic or Greece. Other most ancient languages prior to the Greek language and spoken in the same territory represented a

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no inglês, no idioma grego moderno e os radicais do idioma grego antigo que os originaram. Conclusão: Muitos trabalhos tratam da verdadeira origem das palavras (etimologia), porém, a maioria não retorna aos radicais originários ou não os relaciona com seu emprego em textos do idioma grego antigo. Ao comparar as maiores obras mundiais relativas à etimologia dos termos gregos, o presente trabalho esclarece as divergências entre a verdadeira origem dos termos anatomocardiológicos e as origens mais aceitas hoje no Brasil pelos profissionais da saúde. Descritores: Etimologia. Terminologia como assunto. Cardiologia.

linguistic substrate of minor importance for the GL. This fact is evidenced by glossological factors existing in that language and not found in any other language [3,4]. The GL, in spite of being the ancient language that fewer changes have undergone over the centuries, it is not grammatically or phonetically identical to Modern Greek. Deviations might have occurred in etymological terms derived from the Greek language. In Brazil, the standardization of terms occurred according to with the Parisiensia Nomina Anatomica (PNA) in 1955. Later, in 1965, it was referred to as Nomina Anatomica (NA). It originated in 1998 the new corpus of anatomical terms called Anatomical Terminology. Since this new corpus was adopted, there is a constant search for consensus. It has been revised, expanded, and modified four times [5]. In several studies similar to the present one, the words are defined accordingly to the authors’ etymological understanding at the time of its creation abroad. Thus, the etymological definitions of the terms currently used are not always consistent with their origin, the ancient Greek language (AGL). The objective of the present study is to analyze the etymology of the terms of the heart anatomy derived from the Greek language through its more ancient radical and to compare it to the etymological definition given currently in Greece and Brazil. METHODS As an initial criterion, in order to perform an analysis of the heart anatomy, we selected terms derived from Greek language contained in the international anatomical terminology. We excluded all the terms derived from Latin. We performed an etymological analysis of the roots used to build the most primitive terms returning to the origins of the AGL and relating them to the terms currently used in Greece and Brazil in their present anatomical terminology. Due to the antiquity of the language, it was also 319


Bezas G & Werneck AL - Greek language: analysis of the cardiologic anatomical etymology: past and present

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necessary to verify the use of terms in various stages of history and analyze them as the meaning contained in the respective texts and passages. Finally, we carried out a crossinformation. Therefore, a criterion for selection was the diversity of sources for bibliographic analysis. We gathered all forms of use of terms of various areas of knowledge. We used etymology books and Greek dictionaries not translated into Brazil from Greek writers and teachers [3,6,7]; philosophy dictionaries and literature [1,8]; Brazilian etymological dictionaries [9-15], specific American and French etymological dictionaries [16-19]; literature and history of the Greek language [4]; translated literature related to several epochs; events and people of Ancient Greece [20-23], and specific articles about etymology [24 -26]. In order to obtain the correct source of terms, their orthography in the Greek language has also been considered, once the linguistic analysis is critical to distinguish between etymological meanings. We examined the use of the studied terms by means of references related to ancient sources, from the Epics of Homer to the references of Aristotle, and we compared the most recognized international etymological lexicons and encyclopedias, including the Greek sources with other Brazilian studies. We did not consider the translation given at the time of the creation of the terms that most often occurred outside Greece. We used to accomplish that, the morphological decomposition of the roots, prefixes and suffixes. We examined the use of the roots in texts of the AGL.

Standard term in Brazil: AORTA English: Aorta AGL term: αείρω(v.) (pronunciation – aíro) ‘lift up, tie, fit into, hang’ MGL corresponding term: αορτή (pronunciation – aortí)

RESULTS Terms analysed: Standard term in Brazil: ANASTOMOSE English: Anastomosis AGL term: αναστομώ(v.) (pronunciation – anastomô) – from αÌνα “up repeatedly” e στόμα “mouth” MGL corresponding term: αναστόμωση (pronunciation – anastómossi) Standard term in Brazil: ANATÔMICO English: Anatomical AGL term: ανα (pronunciation aná) / τέμνω(v.) (pronunciation – témno) MGL corresponding term: ανατομικός (pronunciation – anatomicôs) Standard term in Brazil: ANGIOLOGIA – ANGIO English: Angiology - Angio AGL term: άγγος (pronunciation – angós) / λόγος (pronunciation – lógos) MGL corresponding term: αγγειολογια (pronunciation – anguiologuía) / αγγείο (pronunciation – anguío) / λόγος (pronunciation – lógos) 320

Standard term in Brazil: ARTÉRIA English: Arteria AGL term: αρτώ(v.) (pronunciation – artô) “hang, hold it high” MGL corresponding term: αρτηρία (pronunciation – artiría) Standard term in Brazil: AUTÔNOMO English: Autonomous AGL term: αυτόνομος (pronunciation – aftônomos) “regulated by its own laws” MGL corresponding term: αυτόνομος (pronunciation – aftônomos) Standard term in Brazil: BRONCO- (MEMBRANA BRONCOPERICÁRDICA) English: Broncho AGL term: βρόχω (approximated pronunciation – bróco) “swallow, devour” MGL corresponding term: βρόγχος (approximated pronunciation – vrôncos) Standard term in Brazil: CARDÍA - CARDIOEnglish: CardioAGL term: καρδία (pronunciation - cardía) “heart” MGL corresponding term: καρδιά (pronunciation – cardiá) Standard term in Brazil: CIRÚRGICO English: Surgical AGL term: χεíρ- (pronunciation aproximada – quir) “hand” / εργον (pronunciation – érgon) “trabalho” / -ικος (pronunciation – ikos) “relative to” MGL corresponding term: χειρουργικός (pronunciation – quirurguikôs) Standard term in Brazil: CLÍNICO English: Clinical AGL term: κλίνη (pronunciation – clíni) “hospital bed” / -ικος (pronunciation – ikos) “relative to” MGL corresponding term: κλινικός (pronunciation – klinikôs) Standard term in Brazil: CORONARIA English: Coronary AGL term: κορώνη (pronunciation – korôni) “recurvate” MGL corresponding term: stefaniaia (pronunciation: stefaniéa)


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Standard term in Brazil: DIAFRAGMA (DIAFRAGMÁTICO) English: Diaphragma AGL term: διαφράσω (pronunciation ‘diafrásso’) “blockade, I make a barrier” MGL corresponding term: διάφραγμα (pronunciation ‘diáfragma’) Standard term in Brazil: EMBOLIA (EMBOLIFORME) English: Embolism AGL term: εμβάλλω (pronunciation – embálo) “something thrust in” / forme (Latim term) MGL corresponding term: έμβολο (pronunciation – ênvolo)

Standard term in Brazil: GÂNGLIO English: Ganglion AGL term: γαγγλίον (pronunciation – ganglíon) “uncertain etymology” MGL corresponding term: γάγγλιο (pronunciation – gânglio) Standard term in Brazil: HISTOLÓGICO English: Histological AGL term: ιστός (pronunciation – istós) “tissue” / λόγος (pronunciation – logos) “treatise, discourse” MGL corresponding term: ιστολογικός (pronunciation – istologuikôs)

Standard term in Brazil: ENDOCÁRDIO English: Endocardium AGL term: ένδον (pronunciation – endós) “inside”/ καρδία (pronunciation – kardía) “heart” MGL corresponding term: ενδοκάρδιο (pronunciation – endokárdio)

Standard term in Brazil: ISTMO (ISTMO DA AORTA) English: Isthmus AGL term: ιθμός (pronunciation – ithmós) “slight constriction” MGL corresponding term: ισθμός (pronunciation – isthmós)

Standard term in Brazil: ENDOTELIO English: Endothelium AGL term: ένδον (pronunciation – endós) “inside” / (επι)θηλή (pronunciation – thilí) “nipple” MGL corresponding term: ενδοθήλιο (pronunciation – endothílio)

Standard term in Brazil: LINFA (LINFÁTICO LINFONODOS) English: Lymph AGL term: νύμφη (pronunciation: nínfi) “mythological being” MGL corresponding term: νύμφη (pronunciation: nínfi)

Standard term in Brazil: ENDOTORÁCICA English: Endothoracic AGL term: ένδον (pronunciation – endós) / θώραξ (pronunciation – thórax) “armour” MGL corresponding term: ενδο ωραχικο (pronunciation: endothorachikô) Standard term in Brazil: EPITÉLIO English: Epithelium AGL term: επί (pronunciation – epí) / θήλιο (pronunciation – thílio) “nipple” MGL corresponding term: επιθήλιο (pronunciation – epithílio)

Standard term in Brazil: LOBO (ARTÉRIAS LOBARES ARTÉRIA LOBAR MÉDIA) English: Lobus AGL term: λοβός (pronunciation – lovôs) “A rounded projecting part bounded by fissures, sulci, connective tissue septa, or other structural demarcations” MGL corresponding term: λοβός (pronunciation – lovôs) Standard term in Brazil: MIOCÁRDIO English: Myocardium AGL term: μυς (pronunciation – mi) “little mouse” / καρδιά (pronunciation - cardiá) “heart” MGL corresponding term: μυοκάρδιο (pronunciation – miocárdio)

Standard term in Brazil: ESPLÂNCNICO English: Splanchno AGL term: σπλάγχνο (pronunciation – splâncno) “viscus” MGL corresponding term: σπλαγχνικός (pronunciation – splancnikôs)

Standard term in Brazil: MIOLOGIA English: Myology AGL term: μυς (pronunciation – mis) “little mouse” / λογια (pronunciation – loguía) “treatise, discourse” MGL corresponding term: μυολογία (pronunciation – miologuía)

Standard term in Brazil: FRÊNICO English: Phrenico AGL term: φρην (pronunciation: frin) “mind” MGL corresponding term: φρένες (pronunciation: frénes)

Standard term in Brazil: PARASSIMPÁTICO English: Parasympathetic AGL term: παρα (pronunciation – para) “parallel to” / συμπαθώ(v.) (pronunciation - simpathô) “I am touched by 321


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the emotions of another person” MGL corresponding term: παρασυμπαθητικός (pronunciation - parassimbathitikôs)

communicated in this language, we would have to be a direct participant in the world in which that language is expressed” [9]. The term cardio- has been used since Ancient Greece with the same meaning of “heart.” The true origin of the term lies in the root of the Indo-European word ‘kerd’, which already had the meaning of heart [4]. The same term is also found in the Epics of Homer as a synonym for cardio- [9]. In Ancient Greece, besides being considered a physical organ, the heart - so often reported in archaic writing - was also considered as an organ of feeling. Until a certain period of the antiquity, the Greeks believed that the heart was the seat of the center of the intellect. Once the organ responds promptly to any strong emotion, many emotions were attributed to it such as joy, pain, fear, anger, tenderness, etc. [4,9]. Remnants of that thought linger today as the heart is reported as an organ of feeling, however, always metaphorically. In fact, for the Homeric man these feelings were the proper functions of the heart. Generally, in Brazil, simple anatomical terms derive from Latin, while the compound terms derived from the Greek. Therefore, cardio- is only found as a form of combination [16]. This is what happens in cardiogenic [Of cardiac origin], cardiology [cardio- + G. logos, study], cardiogram [cardio+ G. gramma, a diagram], etc. In the international anatomical terminology, we can find the term cardia, which derives from the same Greek root [G. kardia, heart]. However, it is used to designate the area of the stomach close to the esophageal opening (cardiac orifice or cardia) that contains the cardiac glands [2,3,14]. According to Jean Riolan, the term cardia was used by the ancients as a synonym for the mouth of the stomach [14]. For example, many of the heart anatomy terms we use today such as cardiology, anatomy, and anastomosis have a French origin. These are loanwords borrowed from the roots of the Ancient Greek Language [3,4]. The term anastomosis has a French origin borrowed from Greek words. It means the communication between two tubular organs, which can occur naturally due to illness or surgery. Galvão [11] translates it as to the action of discherge. Fernandes [14] puts it another way: “through the mouths.” Etymologically, the term comes from two roots of the Ancient Greek Language, ανα “up, repeatedly, consecutively, continually” and στόμα “mouth” with this same meaning from the Indo-European language as in ‘-Stom’: “mouth” [3] . The term angiology comes from the roots ‘άγγος’ and λέγω (v.). The term αγγείο, from the Modern Greek Language, has meanings as the following: container for storage or transport of fluids (jar); conductive tubes in the body conveying blood or other organic fluids (arteries, veins, lymph vessels) [3,6,16]. In the Ancient Greek Language, the root ‘άγγος’ had the meaning of “compartment, pot, vase, amphora. The term “Λόγος” comes from λέγω (v.)

Standard term in Brazil: PERICÁRDIO English: Pericardium AGL term: περικαρδίου (pronunciation – perikardíu) “around the heart” MGL corresponding term: περικάρδιο (pronunciation – perikárdio) Standard term in Brazil: SIMPÁTICO English: Sympathetic AGL term: συμπαθώ(v.) (pronunciation - simpathô) “I am touched by the emotions of another person” MGL corresponding term: συμπαθητικός (pronunciation – simbathitikôs) Standard term in Brazil: TRÍGONO (TRÍGONO FIBROSO - DIREITO E ESQUERDO DO CORAÇÃO) English: Trigonum AGL term: τρι- “três” / γονία (pronunciation – gonía) “knee/genu, angle” MGL corresponding term: τρίγωνο (pronunciation: trígono) DISCUSSION The evolution of a language is extremely dynamic, which causes some difficulty in understanding the term real meaning. The words mentioned should be related to feelings, aggregate cultural values and customs of each civilization [4,9]. When we deal with such an old language as the Greek language, the words are born for a purpose and over the centuries, these words can acquire a totally different meaning [9]. Ruth Benedict, the anthropologist, in her book “The Chrysanthemum and the Sword,” written in 1946, says that the culture is like a lens through which we view the world. “The lens through which a nation sees life is not the same as other nation uses. It is difficult to be conscious with eyes through which we look” (Benedict, 2002). For example, the term soma that in the modern Greece has always meant the body, in the Ancient Greek of Homer did not have that meaning. As a matter of fact, it had no meaning in living man. The term “soma” came to exist only after death, i.e., the closest meaning transferred to the present day would be “corpse” [9]. Giovanni Reale says in his study: “the language is much more than an instrument by which thought expresses the thing, as it is the language itself that brings to light the thing and allows the mind to think of it. The language is never susceptible to a perfect translation to another language, because to reach an understanding and a complete expression of the messages 322


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meaning “speech, discourse” [3,4,6]. Although derived from the Ancient Greek Language, the term angiology has its origin in France as ‘angiologie’. There was a modification of the spelling over the years. This facilitated the pronunciation, and the term angiology entered common usage in Brazil. Semantics was maintained. The term “anatomical” is used both in Brazil and Modern Greece (ανατομικό). It has the following meaning: relating to anatomy. The term anatomy had its origin in France. It was borrowed from the roots of the Ancient Greek Language ana (ανα) “from the bottom up, repeatedly” and têmno (τέμνω) “to cut, to open” [3.14]. As a science that studies the various body structures, anatomy has been used in Greece since 1738 [3]. It was translated by Edgar A. M. Morales as: “cut on all sides of an animal body in order to see its forms and to study its various parts” [26]. The term artery is used both in the Modern Greek Language (αρτηρία) and in Brazil (artéria). Considered by the ancients as “air conduits [aeir + thirón], once blood was not found in the arteries after death [14]. A primitive meaning was “trachea”. At the time of Aristotle, it was called trachea-artery [11]. However, the most primitive root, that is, the true origin in the Ancient Greek Language is ‘αρτώ’ (pronunciation - artô), which means “hang, hold high” [2,3,6]. There is a relation of this term under the root ‘αείρω’, which means “float, lift, connect, fit.” Therefore, it is related to the term aorta. The term αέρα (pronunciation - aéra) also comes from the root ‘αείρω’, which means “air” [3]. The term aorta is used both in Modern Greek Language (“Αορτή”) and in Brazil (“aorta”). The term of the Ancient Greek Language “αείρω” (v), to suspend, to lift, to connect, to fit, etc., gave birth to the noun αορτήρ, which means “suspensor” (pronunciation - aortír) [3]. Thus, the aorta might be defined as the artery connecting (binds) the heart to the whole arterial tree, and also as being the site of “setting” of the entire system to the heart. Aristotle defined as flebos the term ‘aorté’, which is translated as a carried or suspended vein [11]. The term broncho- in Human Anatomy carries the same meaning in both the Modern Greek Language and Brazil. Its etymology is uncertain. However, by linguistic analogy, it is possible to relate the standardized term in Brazil and Greece with the verb of the Ancient Greek Language ‘βρόχω’, which means “swallow, devour.” The origins of the term coronary are found in the Ancient Greek Language κορώνη (pronunciation Koróni). It means “crow” or “hooked/recurved” [3,18,19]. The term used today in Brazil comes from ‘the Latin ‘Corona’, which is a loanword from the term crown. However, it was borrowed from the Ancient Geek Language whose meaning was hooked/recurved or crow [3,18,19]. In the Modern Greek Language, the term corresponding to coronary is ‘stefaniaia’, which comes from stephane (pronunciation stefané) that means crown.

Although the term is used even in Greece with the meaning of crown (stefaniaia), its etymology relies on the Ancient Greek κορώνη, which meant ‘hooked/recurved’ [3,18,19]. Etymologically, the term could be translated as ‘curved or bent near its tips like the beak of a crow’. The term autonomus has been used since the Ancient Greece as ‘αυτόνομος’ (pronunciation aftônomos) with the meaning of “something or someone that is governed by its own laws; it does not depend on another person; independent; having independence or freedom from control by external forces” [1,3,6,7]. In the Modern Greek Language, the corresponding term is the same: αυτόνομος (pronunciation - aftônomos). It comes from the terms of the Ancient Greek Language αυτό, meaning “own, for my own account” and νόμος, meaning “law.” Autonomous was also used in the field of philosophy to designate the independence of the will toward an object of desire and as the ability to establish itself as a proper law [1]. The surgical term, “χειρουργικός” (pronunciation: quirurguikôs), has been used in medicine since Ancient Greece. It comes from the roots of the Ancient Greek Language χεíρ (approximate pronunciation: Kir), which means “hand”, εργον meaning “work”, and the suffix –ικός, meaning “relating to” [3.16]. The term, “κλινικός” (clinical), is used in medicine both in Greece and Brazil with the same meaning: “what is relative to the medical practice for the patient’s therapy.” The meaning of this term is relatively new, and it appeared in France deriving from the term “clinique.” Centuries before, Galen had already referred to the term ‘κλίνη’ as “hospital bed.” All related terms (clinic, clinical, clinoid, etc.) derived from the same root of the Ancient Greek Language, “κλίνη”, which in turn comes from the term ‘κλίνω’ (v.), which also comes from the AGL meaning “to bow, to tilt.” In ancient writings, it specifically refers to the inclination of the body in any direction from the standing position: to incline, to lie down. The term diaphragm is used in the area of Human Anatomy to designate the main respiratory muscle separating the thoracic and abdominal partitions. It comes from the Greek term ‘διαφράσω’ (v.) meaning “a partition wall, a barrier” [1,3]. The term derives from the following roots: ‘Ana’ = ‘through’ and frásson = ‘encircle, surround, enclose’ [1,3,16]. Emboliform is a hybrid term (of a confusing nature), which comes from the Greek root έμβολο (pronunciation Ênvolo). It is also used in Brazil with a medical meaning of “mass of clotted blood or any substance not dissolved in the bloodstream able to occlude blood flow.” Although it has been translated as ‘wedge’, the true origin of the term “εμβάλλω”, from the Ancient Greek Language, is “to put into” [3]. The term was used by Hippocrates to describe the replacement of a bone in place [12]. It also comes from two roots of the Ancient Greek Language, ‘ev’ (pronunciation - en), which had the meaning 323


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of “inside,” “part of” + ‘βάλλω’ (v.), which meant “to put” [3,6]. In Homeric texts, the term was already used in the meaning of “to put.” Currently, in Greece, the term ‘eμβολia’ means a vaccine (plural, eμβολia). The prefix ‘endo-‘, from the ancient Greek ένδον (pronunciation - éndon), is a compound term, and it is present in endocardial endothelium, endothoracic, etc. Its origin arises from two roots of the ancient Greek ‘ev’ (pronunciation - en), which means “inner, absorbing, or containing,” and ‘e-δον’ meaning “home,” “inside the house” [3,6]. However, this word root used to express the word house contained in itself a “metaphoric” sense, referring to our most intimate environment, the body’s internal environment [1,3]. Transcribing it according to its use in ancient texts, we reach the meaning of “inside our own body.” The prefix peri-, which composes the word pericardium, is a common prefix in terms derived from the Greek language, as well as the prefix endo-. The prefix peri- has its origin arising from the AGL word “πέριξ” (pronunciation - périks). It had the meaning of “around, about, near, on all sides” [3.16]. In the Modern Greek Language, the term ‘περί’ (pronunciation - peri) carries the following meanings: regarding, more or less, around, or near [16]. Endothelium comes from the ancient Greek Language term ‘ένδον’, which means “inside the body” and the term ‘θηλή’ meaning “nipple,” that in turn arises from the term θηλώ, which indicates “to suck, to breastfeed.” The term ‘Θηλώ’ is related to female gender. The same word root forms the word “feminine,” which in the Greek language means ‘θηλυκός’ (pronunciation - thilikôs). The term thorax (θώραξ) had the meaning of “armor” in ancient Greece. It comes from the word endothoracic. It referred to a type of leather or metal armor that protected the warriors’ chest and back. Term sympathetic has its origin in the ancient Greek Language ‘συμπαθώ’ (v.) (pronunciation simbathô). It first meant: “I am touched with the emotions of another person; I feel the pain of another person.” It is formed by the ancient Greek roots ‘συμ’ and ‘πάθσκω’ (pronunciation páthsco) meaning “with, together” and “I suffer”, respectively. It is a term related to suffering caused by a disease [2,3,6]. The prefix para- (παρα - pronunciation para), like in the word parasympathetic, is quite common in the Greek language. It conveyed the meaning of “adjacent, alongside, near, parallel to.” In the Modern Greek Language, the term παρά (pronunciation - pará) has several meanings, such as “on the contrary, reduction, lack of, less, imposition or exception (παρά) [I do not want anything besides your help], alternation [(day = παρά) (every other day)], near, far from, and at the side of [16]. The term splanchnic (σπλαγχνικός) refers to “the viscera.” It has its origin arising from the ancient Greek Language σπλάγχνο, which means “viscus.” The term is also related to the word σπλήν (pronunciation - splín). It conveys a similar

meaning in the ancient Greek Language. In the Modern Greek Language, the term ‘σπλάγχνο’ refers to the viscera and the term ‘σπλήν’ to the spleen. The term lobe (λοβός) both in Greece and Brazil is used in Human Anatomy to describe each part of the same organ bounded by fissures, sulci, connective tissue septa, or other structural demarcations. In the ancient Greek Language, it came from the word ‘λοβός’, which had the meaning of “rounded projecting protrusions bounded by a fissure or a section” [3]. The term lymph comes from the ancient Greek word nínfi. It arrived in Brazil through the Latin word lympha. It was translated by many authors as clear spring water [3.12]. However, the term nínfes (nymphs) refers to minor youth female nature deities, which always wear white dresses. They are believed to dwell in mountains and groves, by springs and rivers, and also in trees and in valleys and cool grottoes. Arising from the same term, the Greek nífi (νύμφη) (nymph) has “bride” and “veiled” among its meanings. The correlation of similar terms of the Greek language is done through the words “freshness, youth, clarity, pureness, serenity” [3,6]. The Greek root thelium (from the Greek θήλιο) as found in endothelium and epithelium, in most studies of Greek etymology is reported as a “nipplelike structure/mamma” [1,15,16] due to the similarity of this tissue with the nipples [15]. According to Greek works, the root has its origin in the Indo-European language with the meaning of “to suck, to breastfeed” [3]. Since the Epics of Homer up to the time of the great Greek philosophers, the Greek term phren- has been cited several times. It has very different meanings. In part, the term is related to a physical body, but most often it appears linked to the emotions and in general to the mind [1,8]. The term also appears as phren, indicating diaphragm [8]. However, this does not seem to be the first definition or translation given by Homer. In most of the passages, the term relates to various feelings and emotions. So one can understand why it is often found translated as “heart.” The term phren is found with two meanings: mind and heart [3,8]. Although in most of the passages from the Epics of Homer, the word phren is found with the meaning of mind, in the Iliad it also appears with the meaning of heart [8]. A convincing explanation for this translation of the term phren as diaphragm or heart existed in a given period of the antiquity; the Greeks regarded the diaphragm, near the heart, as the center of the intellect! [4,8].

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CONCLUSION Most of the terms from the Greek language were created outside of Greece. They were loanwords - a word borrowed from a donor language and incorporated into a recipient language. The terms were borrowed from the roots of the Ancient Greek Language. Through a survey of the origins


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of the Greek language, we could verify that there is a wide divergence between the etymological meaning perceived by the authors and the etymology of the roots used to build the international standardized terms of the heart anatomy. There are many studies that address the real origin of words (etymology), but most of them will not go far beyond the birth of the term, which is usually composed of two or more radicals from the Ancient Greek Language. We analyzed many terms according to the meaning given to them at the time of their creation, leaving aside the analysis of the primitive radicals. Obviously, one cannot reach absolute conclusions on this specific area, but in order to carry out this search it is necessary to consider the precepts of analogy and language, especially for a language as complex as the ancient Greek. The present study compared the world’s greatest works on the etymology of Greek words published in several languages, including citations on the earliest sources of the AGL: the Epics of Homer. Thus, it was possible to clarify some discrepancies between the true origin of the heart anatomy terms and the most accepted terms today in Brazil by health professionals.

10. Guérios MRF. Dicionário de etimologias da língua portuguesa. Curitiba:Editora da Universidade Federal do Paraná;1979. 11. Galvão R. Vocabulário etimológico, ortográfico e prosódico das palavras portuguesas derivadas da língua grega. Itatiaia:Livraria Garnier;1994. 12. Soares JL. Dicionário etimológico e circunstanciado de biologia. São Paulo:Editora Scipione;1993. 13. Heckler E, Back S. Massing E. Dicionário morfológico da língua portuguesa. Porto Alegre:Universidade do Vale do Rio dos Sinos UNISINOS;1984. 14. Fernandes GJM. Paulo:Plêiade;1999.

Eponímia

e

etimologia.

São

15. Diaz G, Douglas CR. Etimologia grega do vocabulário científico. 1ª ed. São Paulo:Robe;1993. 16. Barnhart RK. Dictionary of etymology: the origins of American English words. Nova York: Harper Resource; 1988. 17. Liddel HG, Scott R. A Greek-English Lexikon tis Ellinikis Glossis. New York:Oxford University Press; 1996. 18. Chantraine P. Dictionnaire étymologique de la langue grecque: histoire dês mots. Paris: Klincksieck; 1977.

REFERENCES 1. Abbagnano N. Dicionário de filosofia. São Paulo:Editora Mestre Jou;1962. 2. Sidéris I. Etimologikon Lexikon tis ellinikis glossis. Atenas:Edit. Ev Athinais;1963. 3. Babiniotis G. Leksiko tis neas ellinikis glossas. Atenas:Centro de Leksikologia da Universidade de Atenas; 1998. p.600. 4. Triandafilídis M. Istoria tns Ellinikis Glossas: apo tis arxes eos tin Ystern arxaiotita. Atenas:Instituto Neoellinikon Spoudoon;1980. 5. Comissão Federativa da Terminologia Anatômica. Terminologia Anatômica Internacional Brasileira. São Paulo: Manole; 2001. 6. Markandonatos G. Vassiko leksiko tis arxaias ellinikis. Atenas: Centro de Leksikologia da Universidade de Atenas; 2002.

19. Le Grand Bailly. Dictionnaire Grec Français. Paris: Hachette; 1973. 20. Bowder D. Quem foi quem na Grécia Antiga: dicionário biográfico. São Paulo: Art Editora - Do original: who was who in the Greek World; 1982 . 21. Jardé A. A Grécia Antiga e a vida grega. São Paulo: Editora Pedagógica e Universitária; 1977. 22. Araújo FC. Homero: a ilíada (em forma narrativa). São Paulo: Coleção Universidade de Bolso. Ed Tecnoprint; 1977. 23. Nunes CA. Homero: Odisséia. Tradução em versos. São Paulo: Tecnoprint; 1977. 24. Wharton ER. An etymological lexicon of classical Greek. London: Percival and Co;1890.

7. Baltás X. Leksiko tis arxaias ellinikis glossas. Atenas: Editora Dimitrios Papadimas;1995.

25. Kachlik D, Bozdechova I, Cech P, Musil V, Baca V. Mistakes in the usage of anatomical terminology in clinical practice. Biomed Pap Med Fac Univ Palacky Olomouc. 2009;153(2):157-62.

8. Reale G. Corpo, alma e saúde: o conceito de homem de Homero a Platão. São Paulo: Paulus; 1999.

26. Morales EA. Enciclopédia etimológica acadêmica. Guatemala:Edit. Setegu; 2010.

9. Silva Júnior C. Vocabulário etimológico de biologia. 6ª ed. São Paulo:Atual Editora;1987.

27. Kemp K. Corpo modificado, corpo livre? Questões fundamentais do ser humano. São Paulo: Paulus; 2005.

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APPENDIX 1: COMMON PREFIXES AND SUFIXES A - AN

AGL prefix: α – αν [pronunciation - an (when before a vowel)] MGL: α – αν [pronunciation - an (when before a vowel)] The prefix indicates “no, not, without, lack of, apart” ANA AGL prefix: αÌνα (pronunciation – aná) – “up”, “upward, upward movement” or “something that occurs for the first time or subsequently”. Uncertain etymology MGL: ανα (pronunciation – aná) – It indicates something that (1) goes up, moves upward, (2) continuously happens, (3) split up, (4) - distribution through a space, (5) - distribution for a period of time. APO AGL prefix: από (pronunciation – apô) “away from, separate from, separation” MGL: από (pronunciation – apô). It indicates: 1- starting place; 2- starting time; 3- comparative; 4- cause. EN IGA prefix: ev (pronunciation – en) Meaning: (1) within 2- during, while, whereas, as long as. MGL: ev (pronunciation – em) It indicates: 1- inside, within, entrance; 2- sum, conquest, possession; 3- increase of ENDOS AGL prfefix: ένδον (pronunciation – endós). Etymologically the term comes from ev (pronunciation – en) that meant “within” “inner” and -δον that meant “house”, “inside the house”. However, archaeological finds from the Greek language, refer to its meaning as “within the body.” MGL: ενδο (pronunciation – endo) Meaning “inner”, “within”. EPI AGL prefix: επί (pronunciation – epí). It indicates 1- over, upon, above; 2- sum; 3-immediately after, subsequently, after. MGL: epí (pronunciation – epí). It indicates: 1- over, upon, above; 2- sum; 3- something else, the besto f a group; 4 immediately after, subsequently, after HIPO RAGL prefix: υπο (pronunciation – ipo) Meaning: “below, under” MGL: υπό – υπ (pronunciation – ipô) Meaning: 1- below, under; 2- under the effect of; 3- Someone who has a hierarchically lower position; 4- something that happens hiddenly, under the table, something that occurs at lower levels 5- backward movement, back; 6- something that exists in small amounts or for a short

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time; 7- something characterized by failure, failure, lack of, something that is below the limit; 8- it indicates something more intense than normal. ÍDE (OIDE) AGL prefix: eídos (pronunciation – ídos) Meaning: “shape”. I.E.origin ‘weid’ (Probable Ancient Greek pronunciation – oid) “I know, I see” MGL: eídos (pronunciation – ídos) Meaning “shaped, as”. it is also used in human biology as “species.” LOGOS AGL root: λόγος (logos) that comes from ‘λέγω’ (lêgo) Meaning “I form a group, I gather infromation” and afterwards I “speak” MGL: λέγω (pronunciation – lêgo) Meaning “to express something through speech”. MI(O)- / MY(O)Combining root meaning relating or pertaining to a muscle. OIDE AGL: eidos (pronunciation – idôs) – The first meaning of ‘eidos’ in AGLI was ‘like the shape of’, a probable link with the term ‘weid’ from the IEL, which meant ‘I know, I see’. MGL: 1- in the shape of; 2- species or kind. PARA AGL prefix: παρα (pronunciation – para) – Meaning “parallel to, by the side” MGL: παρά (pronunciation – pará) – It indicates 1- contrary to; 2- decline, miss, lack, less (he lost the game by 5 points - παρά (by); 3- exception or imposition (I do not want anything from you (beyond) (παρά) your help); 4- alternation (every two days); 5- place, locality: position in relation to something (close by, far away, by the side of). PERI AGL prefix: πέριξ (pronunciation – périks) Meaning “around; on all sides” MGL: περί (pronunciation – perí) Meaning 1- in respect to; 2more or less; around; 3- close by, around. SINAGL root: ξύν (pronunciation – ksín) Meaning “with, together with, along with” MGL: συν- (pronunciation – sín) it is also used as συ-, συμ-, συγ-, συλ-, συσ e συρ. It indicates: 1- something that happens together or with the help of another; 2- a common feature in more than one object or person; 3 – related to more than one thing or person.


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CASE REPORT

Heart retransplantation in children without the use of blood product Retransplante cardíaco em criança sem o uso de hemoderivados

Antonio Alceu dos Santos1, José Pedro da Silva2, Luciana da Fonseca3, José Francisco Baumgratz4 DOI: 10.5935/1678-9741.20120051

RBCCV 44205-1388

Abstract This article reports a case of a cardiac retransplantation without the use of blood products, in a 6 year old child, with severe dilated cardiomyopathy after chronic graft rejection and refractory to clinical treatment. To avoid a blood transfusion in this surgery a multidisciplinary approach was planned, which involved the use of preoperative erythropoietin, acute normovolemic hemodilution and intraoperative cell savage with autologous blood recovery system, as well as a meticulous hemostasis and reduced postoperative phlebotomy.

Resumo Este artigo relata um caso de retransplante cardíaco sem o uso de hemoderivados, em uma criança de 6 anos, com miocardiopatia dilatada grave, após rejeição crônica do enxerto e refratária ao tratamento clínico. Para evitar transfusão sanguínea nessa cirurgia, foi realizado planejamento multidisciplinar, que envolveu o uso de eritropoietina no pré-operatório, hemodiluição normovolêmica aguda e recuperação de sangue autólogo no intraoperatório (cell saver), bem como hemostasia meticulosa e redução de flebotomias no pós-operatório.

Descriptors: Heart transplantation. Child. Erythropoietin. Blood transfusion, autologous. Graft rejection.

Descritores: Transplante de coração. Criança. Eritropoetina. Transfusão de sangue autóloga. Rejeição de enxerto.

INTRODUCTION Medicine is one of many areas of knowledge related to the maintenance and restoration of health. It works in a broad sense, with the prevention and cure of human and animal diseases in a medical context. This became evident in 1967 when it performed the first heart transplant between humans, by Barnard [1]. That same year, Kantrowitz et al. [2] tried, unsuccessfully, the first transplant in newborn patients with Ebstein anomaly. Only in 1984, after the introduction of cyclosporine in the handling of rejection,

1. Specialist in Cardiology, Hospital Beneficência Portuguesa of São Paulo, Assistant Team Physician Dr. José Pedro da Silva, São Paulo, Brazil. 2. PhD in Cardiovascular Surgery, Hospital Beneficência Portuguesa of São Paulo, São Paulo, Brazil. 3. PhD in Cardiovascular Surgery, Hospital Beneficência Portuguesa of São Paulo, São Paulo, Brazil. 4. Specialist in Cardiovascular Surgery, Hospital Beneficência Portuguesa of São Paulo, São Paulo, Brazil.

which Bailey et al. [3] performed the first transplant in a child with the hypoplastic left heart syndrome (HLHS). In children with severe cardiomyopathy refractory to medical treatment, as in the case of non-compacted myocardium [4], or cardiogenic shock [5], heart transplantation is imposed as saving measure. The first heart transplant in an adult without use of blood transfusion occurred in 1985 [6]. At the Congress of the Brazilian Society of Cardiology (CSBC), 2009, a heart transplant was reported in a child 2 years and 9 months, without the use of blood products [7]. Neonatal and infant

Work performed at Hospital Beneficência Portuguesa of São Paulo, São Paulo, Brazil. Correspondence address: Antonio Alceu dos Santos Rua Maestro Cardim, 769 – Bela Vista – São Paulo, SP Brasil – CEP: 01323-001 E-mail: antonioalceu@cardiol.br Article received on January 22nd, 2012 Article approved on April 23rd, 2012

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Abbreviations, acronyms & symbols CPB CSBC ANH NYHA rHuEPO HLHS

Cardiopulmonary bypass Congress of the Brazilian Society of Cardiology Acute normovolemic hemodilution New York Heart Association recombinant human erythropoietin Hypoplastic Left Heart Syndrome

cardiac transplantation has enabled survival and improved quality of life in children with severe myocardial dysfunction [8]. The graft failure occurs in approximately 7% of heart transplants in children [9] and in these cases, retransplantation becomes the only therapeutic option. Well-defined strategies have enabled to reduce the use of blood transfusions in cardiac surgery [10,11]. The treatment by cardiac retransplantation, particularly for pediatric patients, is what has reduced prospects for organ procurement in a timely manner, especially at the lower weight and reduced availability of compatible donors. Recently, we discovered, after research in national and international literature, which had not yet been reports of retransplantation in children without the use of blood transfusion. Thus, we report a case of cardiac retransplantation in a 6 year old child without blood transfusion. The study was approved by the Ethics Committee in Research of the Hospital Beneficência Portuguesa of São Paulo (São Paulo, SP, Brazil). CASE REPORT One child, female, with a diagnosis of HLHS at birth, was submitted initially to the first (04/11/2003) and second (03/19/2004) stage of the correction protocol Norwood. After 2 years and 4 months, she developed severe myocardial dysfunction, cardiac transplantation is necessary, performed on 29.07.2006, without the use of blood products [7]. The patient was uneventful until 2009, when she was again admitted to the Hospital Beneficência Portuguesa of São Paulo, with 6 years, weight 16.6 kg and body surface area of 0.69 m², respectively, diagnosed with congestive heart failure functional class IV according to New York Heart Association (NYHA), and ventricular tachycardia in severe chronic rejection refractory to immunosuppressive therapy (cyclosporine, mycophenolate , methylprednisolone), as well as the use of vasoactive drugs (dobutamine, milrinone, norepinephrine), evolving with rapid clinical deterioration, even to cardiogenic shock, requiring mechanical ventilation. A transthoracic echocardiogram revealed poor left ventricular function to a significant degree, with delta D of 16%. Due to this large hemodynamic instability without 328

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response to medical treatment, he was appointed the new heart transplant. For religious reasons, parents requested that staff apply in this case the protocol management and conservation of blood to serious and complex heart surgery, the team created especially for surgery in adults but also in some cases in children, as shown in the CSBC, in 2011 [12]. With a more restrictive conduit for blood transfusion [13], this surgery was accepted. Preoperatively, the child showed normal levels of hemoglobin (13.0 g / dl), hematocrit (38 mL / dL) and platelets (146 mil/mm3), nevertheless, we promptly began treatment with recombinant human erythropoietin (rHuEPO 600 IU / kg / week), ferrous sulphate (10 mg / kg / day), folic acid (5 mg / day), and cyanocobalamin (vitamin B12 5000 IU / day) because the optimum result of the stimulus erythrocytes occurs later after the first week [14]. With a schedule of any team (surgeon, physician, anesthesiologist, intensive care), was performed orthotopic cardiac retransplantation, on 12/13/2009, successfully and without administration of blood products. The total time of ischemia was 180 minutes. For surgery, we mini-circuit (miniSCC) without human albumin in the priming, controlled hypotensive anesthesia, normothermia, acute normovolemic hemodilution (ANH) and, crucially, intraoperative recovery of cells (cell saver), and meticulous hemostasis. Postoperatively, the child was kept normotensive and normothermic and also minimized the phlebotomy. RHuEPO were reintroduced, iron, vitamin B12 and folate and the beginning of immunosuppressants. The dose of cyclosporine was controlled according to their serum by means of radioimmunoassay method, maintaining the level of 300-400 ng / mL. The dose of mycophenolate sodium was 11.2 mg / kg / day. The lowest level of hemoglobin after surgery was 9.7 g / dl. Patient was discharged 40 days after transplantation and with normal levels of hemoglobin (Figure 1).

Fig.1 - Hemoglobin levels during hospital stay


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cell mass (iron, folate and rHuEPO) [29,30], and the HNA, the Intraoperative recovery of cells [27] and, crucially, the surgical technique with meticulous hemostasis. Thanks to this program, multiple blood transfusions have been reduced or even avoided, especially in case of retransplantation. Fig.2 - Doppler echocardiogram showing normal biventricular cardiac function

Since the retransplantation by that date, the child is in excellent general condition with normal biventricular cardiac function at the Doppler echocardiography (Figure 2), with no sign of rejection and lack of toxicity by immunosuppressants.

CONCLUSION It was possible to perform a cardiac retransplantation without the use of homologous blood in a child with severe dilated cardiomyopathy after chronic graft rejection and irreversible drug therapy, using a program management and conservation of blood, and rigorous multidisciplinary planning. Blood transfusions can be avoided or reduced when it is meant to preserve the autologous blood.

DISCUSSION Since the first reported case of retransplantation in 1977 [15], experience with this procedure is still limited, especially in children. Vasculopathy and acute or chronic rejection of the graft represent the main indications [16]. In 1964, we performed the first heart surgery in the world without blood transfusion [17], and since then several other similar cases have been described in the literature [18]. Although some studies show, first, that surgery with massive bleeding not treated with blood transfusions increase the risk of death [19], which actually has been observed in the last decade, several studies showing increased morbidity [20], and fundamentally increase in mortality related to the practice of blood transfusions [21,22]. Another extension problem worldwide is the shortage of blood, raising great concern. In a situation of increasing demand for blood and blood products, with a stationary trend of donations, the emphasis is on lack of stocks in several countries [23]. In Brazil, the demand for blood increases 1% per year, while expectations for growth of blood donations ranging from 0.5% to 0.7% per year [24]. All this has contributed to seek medical treatment options [11] and more restrictive strategies [25] to avoid or minimize blood transfusions. We have many protocols in the literature for performing pediatric heart surgery free of homologous blood transfusion, first, we mention the proposed by Gomez et al. [26], who enumerated several strategies in pre-, intra-and postoperatively. In 2008, other authors confirmed the efficacy and safety of these programs [27]. Another protocol considers the pre-autologous blood donation associated with the administration of erythropoietin [28]. Similarly, since 2002, also developed a program of management and conservation of homologous blood for cardiac surgery, which basically boils down to increase red

REFERENCES 1. Barnard CN. The operation. A human cardiac transplant: an interim report of a successful operation performed at Groote Schuur Hospital, Cape Town. S Afr Med J. 1967;41(48):1271-4. 2. Kantrowitz A, Haller JD, Joos H, Cerruti MM, Carstensen HE. Transplantion of the heart in an infant and an adult. Am J Cardiol. 1968;22(6):782-90. 3. Bailey LL, Nehlsen-Cannarella SL, Concepcion W, Jolley WB. Baboon-to-human cardiac xerotransplantion in a neonate. JAMA. 1985;254(23):3321-9. 4. Croti UA, Braile DM, Moscardini AC, Kozak ACLFBM. Transplante cardíaco em criança com miocárdio não compactado. Rev Bras Cir Cardiovasc. 2010;25(2):261-3. 5. Jatene MB, Miana LA, Pessoa AJ, Riso A, Azeka E, Tanamati C, et al. Transplante cardíaco pediátrico em vigência de choque cardiogênico refratário: análise crítica da viabilidade, aplicabilidade e resultados. Arq Bras Cardiol. 2008;90(5):360-4. 6. Corno AF, Laks H, Stevenson LW, Clark S, Drinkwater DC. Heart transplantation in a Jehovah's Witness. J Heart Transplant. 1986;5(2):175-7. 7. Santos AA, Silva JP, Fonseca L, Baumgratz JF, Lianza AC, Lima DLC, et al. Transplante cardíaco sem uso de hemotransfusão em criança com hipoplasia de coração

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esquerdo. Arq Bras Cardiol. 2009;93(3 supl 1):29. Disponível em: http://www.arquivosonline.com.br/2009/9303/pdf/ Resumo_Comunicacoes_64CBC.pdf Acesso em: 6/4/2012.

19. Benson KT. The Jehovah’s Witness patient: considerations for the anesthesiologist. Anesth Analg. 1989;69(5):647-56.

8. Barbero-Marcial M, Azeka E, Camargo PR, Riso A, Jatene M, Soares J, et al. Transplante cardíaco neonatal e infantil. Arq Bras Cardiol. 1996;67(3):165-70. 9. Mahle WT. Cardiac retransplantation in children. Pediatr Transplant. 2008;12(3):274-80. 10. Souza HJB, Moitinho RF. Estratégias para redução do uso de hemoderivados em cirurgia cardiovascular. Rev Bras Cir Cardiovasc. 2008;23(1):53-9. 11. Mackenzie CF, Shander A. What to do if no blood is available but the patient is bleeding? South Afric J Anaesth Analg. 2008;14(1):39-43. 12. Santos AA, Silva JP, Fonseca L, Baumgratz JF, Freire R, Castro RM, et al. Protocolo de gerenciamento e conservação do sangue em cirurgias cardíacas graves e complexas. Arq Bras Cardiol. 2011;97(3 Supl.1):59. Disponível em: http:// www.arquivosonline.com.br/2011/9703/pdf/TL-66-CBC.pdf Acesso em 6/4/2012. 13. Lacroix J, Hébert PC, Hutchison JS, Hume HA, Tucci M, Ducruet T; TRIPICU Investigators; Canadian Critical Care Trials Group; Pediatric Acute Lung Injury and Sepsis Investigators Network, et al. Transfusion strategies for patients in pediatric intensive care units. N Eng J Med. 2007;356(16):1609-19. 14. Aguiar IFVP, Krebs VLJ, Gualandros SFM, Silveira PAA, Vaz FAC. Efeitos da eritropoetina recombinante humana em recémnascidos pré-termo com doenças infecciosas. Rev Assoc Med Bras. 2007;53(1):90-4. 15. Copeland JG, Griepp RB, Bieber CP, Billingham M, Schroeder JS, Hunt S, et al. Successful retransplantation of the human heart. J Thorac Cardiovasc Surg. 1977;73(2):242-7. 16. Richmond ME, Addonizio LJ, Hsu DT, Mital SR, Mosca RS, Quaegebeur JM, et al. Cardiac retransplantation in high risk pediatric patients. Pediatr Transplant. 2007;11(6):615-23. 17. Cooley DA, Crawford ES, Howell JF, Beall AC Jr. Open heart surgery in Jehovah's Witnesses. Am J Cardiol. 1964;13:779-81. 18. Ott DA, Cooley DA. Cardiovascular surgery in Jehovah’s Witnesses. Report of 542 operations without blood transfusion. JAMA. 1977;238(12):1256-8.

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20. Banbury MK, Brizzio ME, Rajeswaran J, Lytle BW, Blackstone EH. Transfusion increases the risk of postoperative infection after cardiovascular surgery. J Am Coll Surg. 2006;202(1):131-8. 21. Ergoren MC, Habib RH, Zacharias A, Schwann TA, Riordan CJ, Durham SJ. Effect of blood transfusion on long-term survival after cardiac operation. Ann Thorac Surg. 2002;74(4):1180-6. 22. Marik PE, Corwin HL. Efficacy of red blood cell transfusion in the critically ill: a systematic review of the literature. Crit Care Med. 2008;36(9):2667-74. 23. Sojka BN, Sojka P. The blood donation experience: self-reported motives and obstacles for donating blood. Vox Sang. 2008;94(1):56-63. 24. Novaretti MCZ. Importância dos carreadores de oxigênio livre de células. Rev Bras Hematol Hemoter. 2007;29(4):394-405. 25. Hajjar LA, Vincent JL, Galas FR, Nakamura RE, Silva CM, Santos MH, et al. Transfusion requirements after cardiac surgery: the TRACS randomized controlled trial. JAMA. 2010;304(14):1559-67. 26. Gomez D, Olshove V, Weinstein S, Davis JT. Blood conservation during pediatric cardiac surgery. Transfus Altern Transfus Med. 2002;4(1):27-33. 27. Jonh T, Rodeman R, Colvin R. Blood conservation in a congenital cardiac surgery program. AORN J. 2008;87(6):1180-6. 28. Komai H, Naito Y, Okamura Y, Fugiwara K, Suzuki H, Uemura S. Preliminary study of autologous blood predonation in pediatric open-heart surgery impact of advance infusion of recombinant human erytrhopoietin. Pediatr Cardiol. 2005;26(1):50-5. 29. Shannon KM, Keith JF 3rd, Mentzer WC, Ehrenkranz RA, Brown MS, Widness JA, et al. Recombinant human erythropoietin stimulates erythropoiesis and reduces erythrocyte transfusions in very low birth weight preterm infants. Pediatrics. 1995;95(1):1-8. 30. Maier RF, Obladen M, Scigalla P, Linderkamp O, Duc G, Hieronime G, et al. The effect of epoetin beta (recombinant human erythropoietin) on the need for transfusion in verylow-birth-weight infants. European Multicentre Erythropoietin Study Group. N Engl J Med. 1994;330(17)1173-8.


MY OPINION

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The medical education and the Unified Health System Alexandre V. Brick1

DOI: 10.5935/1678-9741.20120052

The 2012 Fraternity Campaign had as its theme “Fraternity and Public Health” and the motto “Let health be spread all over the Earth.” The objective of the National Conference of Brazilian Bishops (NCBB) was to reflect on the reality of Brazil’s healthcare and encourage the mobilization for improvements in public service and reinforces the need for greater attention to the sick in their quest for a healthy life. It focuses on the inefficiency of the Unified Health System (UHS) at variance with the particular services, which is still reinforced by budget cuts, subjecting the patient to long lines for the service, taking a long time to take exams, lack of vacancies in hospitals and even medications. Noting that health promotion is not a favor from the government, but a social right, the campaign urged Brazilian students to this debate, because there is no point examining the inefficiency of this service without a commitment to promote improvements, an important factor for their own professional training of students, including the implementation of interdisciplinary training. In evidence to the setting of public policies in health, training of health professionals (here, specifically, medical training) represents an arid terrain that raises questions and conflicts and the changes it requires. In the management, it is really hard to make the school / university to work as a hospital or an orchestra. In hospitals, the excuses are in cemeteries. In orchestras, the discord is answered by people booing them. Representing privileged sites of knowledge production and discussion, the schools still reflect and reproduce the logic of the fragmented scientism itself, failing to leverage the very richest in the field of education: possible relationships to be developed between professor and student, and later on, revert to the relationships established between professionals and their patients, or between those

1. Full Member of the Brazilian Society of Cardiovascular Surgery; President (2004-2006).

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who care and who are cared for. The neglect of the area of interpersonal relations has been expressed, among other results, the low rates of resolution of the UHS, the dissatisfaction of many professionals and users of services and use of high-cost procedures, which are often unnecessary. We can assume that, as constitutionally guaranteed, the USH as the ordering of human resources in health is still restricted to the theoretical dimension. Recognizing it as a training officer requires extensive restructuring in medical curriculum, specifically to be held by successive and ongoing curricular innovations, guided by the principle of comprehensiveness - complex notion that articulates concepts and practices of health - and the review process labor and management in health. For this purpose, disruptions of the biomedical paradigm are necessary, which still maintains health practices and many of the medical curricula in Brazil, and the simplistic concept that “being healthy is not a disease,” which means removing the focus of welfare actions and understand that care, rather than assistance, should combine actions of disease prevention, health promotion, beyond cure and rehabilitation - all requiring plurality of knowledge, and also interdisciplinary and multiprofessional teamwork , preferably network. However, these actions do not occur by themselves, they involve a number of procedures and decisions that depend on the government, managers of services, the community and in particular, the academic world. How can the courses organize themselves to form a professional capable of working under this new paradigm in the health area? The National Curriculum Guidelines (NCG) [1] for the courses in the area of health, approved in 2001 and resulting from a process of discussion between government representatives, professors, students, pro-deans and principals of schools, among others, are designed to guide their training, based on general knowledge and emphasis on social commitment. This means rethinking the role of the school that, until then, would never interact with society. 331


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Abbreviations, Acronyms & Symbols NCBB NCG UHS UNESCO

National Conference of Brazilian Bishops National Curriculum Guidelines Unified Health System United Nations Educational, Scientific and Cultural Organization

If taken as a benchmark for innovation, these guidelines represent undoubtedly a major task for the institutions of higher education, by introducing new elements, which show forms of organization and management of teaching that have never been used in Brazil’s academic levels. It is proposed to guide the medical courses, among others, to innovate their curricula so that they are linked to the needs of Brazilian society, seeking “dialogue” of the curriculum projects with the social context in which the university is a part; guiding the training of professionals who are able to act at different levels of health care, being competent to work, especially in primary care and social responsibility. This is a new fact that requires a high level of technical complexity. However, there is a long way to go, in which universities play an important role as agents of this process. Medical schools are, mostly, playing a dichotomized training, disciplinary expressed in the curriculum, fragmented and focused on specialties, with the prevailing field of practice the university hospital, emphasizing the procedurecentered health practices disregarding the user- centered ones. Approaching the guidelines of UHS, it is not hard to see that the project of transforming the health care of the Brazilian population has been designed without taking into account the actors who would make the system work. By using an analogy: a machine with high technology and high complexity does not work if there is someone able to operate it. This can be transcribed to the current policy of Public Health, created a Unified Health System, but those involved in its implementation, operation and maintenance are not committed or prepared to act in this system, since the training institutions did not follow the changes resulting from this new orientation. In theory, it is attributed to the UHS the authority to order the formation of human resources in health, based on a new model that integrates the theoretical with the practical services. It is necessary and urgent to the relationship that the university should establish with the UHS, using inclusive public policies that are being implemented to ensure this integration. The debate on the formation and development in the health area as a strategic move to drive the agenda of renewal and reform in the health sector, therefore, of a deep understanding that health sector reform as profound renewal of health organizations, does not happen without 332

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an education policy in the sector. [...] Although there is no doubt that a thorough reform process cannot be done without major changes in the ethical, technical and institutional personnel profile [...], no reform will be done without changing the quality relations of health care, failing to improve the technical organization of the system and which does not generate, in the actions of users and services or the population, the sense of caution. In our view, the curricular innovation correspond to the changes that seek to build new processes for training of professionals in their relations with the socioeconomic structure, involving those relationships, others for the content, processes and methods of teaching / learning. Therefore, it includes significant changes in the curriculum, which can become the embryo of major changes in university-school-community. In the text of the NCG, for example, out of the 22 skills and abilities listed for the graduates of medical school, most of them indicate an action, behavior, a result that the professional must meet, which we briefly removed from the official text: [...] To communicate adequately with their colleagues, patients and families, performing with proficiency anamnesis [...]; properly diagnosing and treating major diseases of human beings [...]; properly utilizing semiological and therapeutic resources [...], performing medical and surgical procedures necessary for outpatient care and for the initial care of emergency care at all stages of life cycle [...] Translated into English. Original text in Portuguese. Few of these skills relate to attitudes and values, as can be seen in those who identify also the text of the NCG: [...] Dealing critically with the dynamics of the market and health policies, recognizing their limitations and refer appropriately, patients with problems that escape the reach of their general education, work in interdisciplinary team [1]. Translated into English. Original Text in Portuguese. However, we must recognize the importance of this document; it clearly demonstrates the intention to emphasize the social role of egress and approximate the medical education needs to the population, political issues, the interdisciplinary work in prevention and health promotion. Even if it is still not extensive, its formulation suggests a breakthrough in terms of innovations in the curriculum of health professionals. In this context, the choice of the theme “Fraternity and Public Health” further strengthens the need for a Medicine in the country aimed to promote health without distinction of social class, with actions that humanize the performance of professionals and students aware of their importance as agents of transformation. The most attentive and competent doctors have


Brick AV - The medical education and the UHS

concluded that we cannot measure the patients’ affliction only by the answers given by the diagnosis machines. Human beings, first of all want to be treated like people. They need sympathy, attention for their ego weakened by the disease, and drug prescriptions and medical procedures itself. The cause-effect relationship, which prints the scientific medicine, needs to read between the lines that inhabit the person that is sick. The United Nations Educational, Scientific and Cultural Organization (UNESCO) proclaimed four guiding principles of Education for this century [2]: a) Learning to know, joining theory and practice, practice and theory that is taught at all; b) Learning to do all that what is taught; c) Learning to live with others; d) Learning to be. In this first decade of this century, we find that citizens are already concerned about “learning to live.” It explains the large volume of information on health and life in the publications [3-5]. The quest for longevity has become universal concern. The medical knowledge loses power if not applied with art. Hippocrates, nearly 2500 years ago, taught that “Medicine is science and art.” Art of scrutinizing the sufferings and aspirations of those who want to heal.

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Antonio Murri gives us a terse statement about the role of the physician: “If you can heal, heal it, if you cannot heal, alleviate it, if you cannot soothe, console.”

REFERENCES 1. Brasil. Ministério da Educação. Diretrizes Curriculares Nacionais (DCN). Resolução CNE/CES Nº 4, de 7 de novembro de 2001. Disponível em: http://portal.mec.gov.br/cne/arquivos/ pdf/CES04.pdf 2. Werthein J, Cunha C. Fundamentos da nova educação. Brasília: UNESCO; 2000. 84p. 3. Saadia A. Temas para discussão e discordância. Rev Bras Cir Cardiovasc. 2005;20(3):II-IV. 4. Braile D. O futuro da cirurgia cardiovascular. Rev Bras Cir Cardiovasc. 2006;21(2):I-II. 5. Barbosa GV. Um novo programa de residência médica em cirurgia cardiovascular com acesso direto. Rev Bras Cir Cardiovasc. 2006;21(4):XII-XIV.

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MY OPINION

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Evidence-Based Medicine - New paradigm or pseudoscience?

Marcelo Derbli Schafranski1

DOI: 10.5935/1678-9741.20120053

It is commonplace to say that the doctor should never stop learning. We partly agree with it. There is no use in reading and rereading hundreds of scientific articles and textbooks which are based on a model full of imperfections, misconceptions and pitfalls, which is the Evidence-Based Medicine (EBM), without a critical sense of these information. Previously believed to be a safe route to follow, as we now have a road full of imperfections that can lead to unpredictable destinations, if used by someone who is not fully aware not only of conceptual errors and ethical dilemmas to which it is always exposed, but mainly of the methodological and statistical artifacts of this model, now almost ubiquitous in medical papers. In 1998, we graduated from Medicine at the Pontifical Catholic University of Paraná, we would joyfully take part in any scientific discussion, especially if we knew a meta-analysis or randomized controlled trial that addressed the topic under discussion, which we would only reveal during the argument. This trick was quite effective. The highest levels of evidence of the emerging EBM were rarely questioned. The years of experience came and along with it the writer Malcolm Gladwell [1], based on studies of the psychologist K. A. Ericsson [2], defined as a deliberate practice, which is essential for us to become unique in what we are accustomed to call the profession. After ten years of operation associated with considerable reading on the subject, we could understand the major flaws and imperfections that underpin the EBM as a model for practice and for teaching physicians. And the in loco observation of constant failures of therapies considered by EBM as the gold standard provided us with the necessary

1. Doctor of Internal Medicine at UFPR; Assistant Professor.

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objective support for the hypothesis that these deficiencies have obvious and direct consequences in the evolution of our patients. EBM standardized number of rules, disseminated in books, textbooks and courses all around the world. But it seems that often forgets to follow them. Initially, the P, usually called the probability that was given the noble task to of having to always be smaller or larger than 0.05, so that the arguments it brings may or may not have any scientific validity. Two conceptual errors allow us to unravel the socalled fallacy of P. Not even its diffuser (the P concept was developed by the British Karl Pearson), the English statistician R. A. Fisher emphatically ruled that we should have this value for statistical significance [3]. It is worse than that, the value of P, however small, does not refer to the null hypothesis (H0), but the data [4]. For example: imagine that, independently on the statistical test we use, correct or not, we get a P of 0.001. Conclusion (right): once H0 is zero, the probability of our data has occurred is 1 to 1000. In other words, H0 is always false. And no matter how small the P is, Fisher never predicted the existence of alternative hypothesis (H1). At first sight, it appears only conceptual preciosity, because it only adds to the unreliability of the P proposed by Fish: in some situations, according to pre-test probability, even when it has the value of 0.05, the chance to confirm an error (nonexistent) H1 can reach 50% [5]. Tossing a coin and trust its result seems more sensible to be equally “accurate” and indeed more economical. This is so confusing that made the famous intellectual Jacob Cohen wonder why it would be relevant to test it if H0 is always zero. [6] We return to Hume’s problem of induction, which could not even be solved by Popper [7].


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Alternatively, the statistician Jerzy Neyman and Pearson Pearson (Karl’s children) created the alpha errors (type-I) and beta (type II), the first may not be greater than 0.05, and the second greater than 0.2. The type II error is also used to calculate the power of the study: subtracting 1, we have statistical power of the sample, which cannot be, by convention, less than 0.8 (80%) [3 ]. Although it is subject to criticism deductive approach, it is a more appropriate model than the questionable significance brought by P. But the EBM turned the alpha error mistakenly into P, combining two different theories. Still, to calculate the estimated sample size needed for a hypothesis test, Neyman-Pearson is used, and to assess the validity of the hypothesis, P designed by Fish. Many studies does not even bother to calculate the sample size required for adequate statistical power [8,9], and few researchers remember to calculate the power of the sample after the final survey, the little-known observed power. Result: It is estimated that about 90% of published trials have insufficient sample, where such data are available [10]. If they were evaluated more carefully, they would hardly integrate specialties consensus, association guidelines and councils. Another key issue involves indicators rarely seen in published scientific studies, the NNT (number needed to treat, derived from the absolute risk reduction - ARR, and not the relative risk reduction, statistical makeup), the NNH (number needed to harm) and effect size, which was idealized by Cohen, previously mentioned here. They are the ones who give us a real clue that the drug or intervention may or may not have any relevance in daily medical practice. The calculators that are used to estimate them can be found on the Internet, all you need to do is simply load the data and interpret them. But don’t be surprised if you find interventions whose NNH is smaller than the NNT or the effect size approaches 0 (zero) almost matching the proposed therapy with placebo, despite a significant P [11]. Even if we apply all the principles properly listed here, we still have to be very careful when analyzing the outcome proposed by researchers [11]. I have already found studies whose primary objective is something like 30% reduction in pain [12], or the improvement of some insignificant percentage in some scores, invented by some doctor or a group of specialists [13]. And all subsequent calculations are developed from these negligible outcomes. Finally, here comes the big conclusion: the proposed therapy is safe and effective. It seems that we live in the safe and effective epidemic. Type it in on Pubmed and check it out. If that were true, the role of medicine in the longevity of the population would be totally different. The article published in 1994 in the renowned journal Milbank Quarterly, by a group of researchers from Harvard University in conjunction with King’s College from London,

began our change of perspective in relation to the true importance of the evolution in medicine during the twentieth century [14]. According to the authors, the increase in life expectancy observed throughout the century was mainly due to improvements in housing conditions, nutrition and sanitation, as well as safer conditions in traffic and at work. Through an extensive and complex method, the researchers concluded that the entire medical breakthrough achieved during the years of the twentieth century extended the human life span into mere five years. Widespread preventive measures such as screening for hypertension and advice not to smoke, added only about six months to life expectancy. Even the extension of life expectancy related to cancer is a subject of inquiry by researchers studying more intensively the inconsistencies of EBM. In his book “Overdiagnosis: Making people sick in the pursuit of health”, the Professor Gilbert Welch [15] shows that the mortality imposed by the majority of cancers, including the breast, prostate and thyroid cancers, is stable as an eternal asystole line since 1975, year that this type of control started to be performed. On the other hand, their diagnosis increases every year. We may affirm that, we have been diagnosing early patients whose cancer would never bother them. The lack of reliable markers of severity, which is still unknown by Medicine, many patients have undergone risk procedures, perhaps unnecessarily so. Recent controversies surrounding mammography [16] and PSA [17] are due to this type of statistical control, which has been increasingly reported by the press that is considered not to have any knowledge about the subject. The EBM has surely its role in this small contribution of Medicine for the longevity of the population, despite the media boosterism of some laboratories that produce drugs and equipment and even some colleagues. It is up to us to change this scenario, not expecting the end of a new century to perhaps repeat the same results with respect to the twentieth century. Editors and reviewers of scientific journals should not accept articles with errors and flaws that contradict the rules of EBM itself, which invented the rules and now has difficulties in following them. Thus, although we cannot be sure that guiding the evolution of medical science certainly will reduce the number of individuals exposed to treatments of uncertain efficacy, and often costly and dangerous. In 1975, the philosopher Ivan Illich opened one of his most controversial works with the sentence “The medical establishment has become a major threat to health” [18]. The EBM, if interpreted only according to individual or corporate interests, and not properly subject to a specialized scrutiny, independent and above all courageous, can take the sad role of corroboration of what was envisioned by the Austrian intellectual for more than three decades. In 335


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other words, EBM is likely to become a fallacious rhetoric that, besides not significantly contributing to the population health, can become iatrogenic, because they do not have a strict control, accessible and reliable information on their possible damage. Still, due to the flexibility of the tools proposed by EBM, the identic data can even create antagonistic evidences [19], and its partly and/or complete publication is delivered to the desire of researchers. Although selecting data (“cherry-picking”) is an ethically questionable attitude, it is perfectly possible, due to the incipient external control of clinical trials [20]. Thus, the ambiguity is incorporated into the binomial analysis / results, putting the knowledge modeling suggested by MBE, as the definition proposed by the philosopher Karl Popper [7], at the same level as other pseudo-sciences as astrology. Therefore, far from a new paradigm, as proposed by the American philosopher Thomas Kuhn [21], the EBM, as it is currently practiced, needs to be radically reorganized to, at least, be respected within the limits of science. Among the challenges to be overcome, the appropriateness of ethical stances are urged, the abandonment of erroneous concepts and normalization of what should be really valued, published and distributed in scientific articles, and the rigorous subtraction of irrelevant analysis that may induce professional misconduct endorsed by EBM. We should now value the anatomical, pathophysiological and pharmacological genuine knowledge, as well as common sense and experience brought by the years, which are the pillars of a science that has survived for more than two thousand years without at least one medication or conduct graced by dogmatic and commoditized recent evidences.

3. Ziliak ST, McCLoskey DN. The cult of statistical significance: how the standard error costs US jobs, justice, and lives. Ann Arbor:University of Michigan Press;2008. 4. Vickers AJ. What is a p-value anyway? 34 stories to help you actually understand statistics. Boston:Addison Wesley;2009. 5. Motulski H. Intuitive biostatistics. Oxford:Oxford University Press; 2010. 6. Cohen J. The earth is round (p<0.05). Am Psychol 1994;49(12):997-1003. 7. Valle B, Oliveira PE. Introdução ao pensamento de Karl Popper. Curitiba:Champagnat;2010. 8. Leguisamo CP, Kalil RAK, Furlani AP. Efetividade de uma proposta fisioterapêutica pré-operatória para cirurgia de revascularização do miocárdio. Rev Bras Cir Cardiovasc. 2005;20(2):134-41. 9. Manrique R, Pavanello R, Magalhães HM. Emprego da nimodipina (oxigen) como protetor cerebral na cirurgia de revascularização do miocárdio com circulação extracorpórea em pacientes idosos. Rev Bras Cir Cardiovasc. 1996;11(4):248-58. 10. Lochner HV, Bhandari M, Tornetta P 3rd. Type-II error rates (beta errors) of randomized trials in orthopaedic trauma. J Bone Joint Surg Am. 2001;83-A(11):1650-5. 11. Gauch R. It's great! oops, no it isn't: why clinical research can't guarantee the right medical answers. Nova Iorque:Springer;2008. 12. Häuser W, Wolfe F, Tölle T, Uçeyler N, Sommer C. The role of antidepressants in the management of fibromyalgia syndrome: a systematic review and meta-analysis. CNS Drugs. 2012;26(4):297-307. 13. Goldman JG, Goetz CG, Brandabur M, Sanfilippo M, Stebbins GT. Effects of dopaminergic medications on psychosis and motor function in dementia with Lewy bodies. Mov Disord. 2008;23(15):2248-50. 14. Welch HG, Schwartz L. Overdiagnosed: making people sick in the pursuit of health. Boston:Beacon Press;2011. 15. Bunker JP, Frazier HS, Mosteller F. Improving health: measuring effects of medical care. Milbank Q. 1994;72(2):225-58.

REFERENCES 1. Gladwell M. Outliers: the story of success. New York:Little, Brown and Company;2008.

16. Welch HG, Frankel BA. Likelihood that a woman with screendetected breast cancer has had her “life saved” by that screening. Arch Intern Med. 2011;171(22):2043-6.

2. Ericsson KA, Krampe RT, Tesch-Römer C. The role of deliberate practice in the acquisition of expert performance. Psycholog Rev. 1993;100(3):363-406.

17. Moyer VA. Screening for prostate cancer: U.S. Preventive Services Task Force Recommendation Statement. Ann Intern Med. 2012;157:11-6.

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18. Illich I. Limits to medicine: medical nemesis, the expropriation of health. London: Marion Boyars Publishers;1975.

20. Califf RM, Zarin DA, Kramer JM, Sherman RE, Aberle LH, Tasneem A. Characteristics of clinical trials registered in ClinicalTrials.gov, 2007-2010. JAMA. 2012;307(17):1838-47.

19. Rucker G, Schumacher M. Simpson's paradox visualized: the example of the Rosiglitazone meta-analysis. BMC Med Res Methodol. 2008;8:34.

21. Kuhn T. The structure of scientific revolutions. Chicago: University of Chicago Press;1996

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Letter to the Editor DOI: 10.5935/1678-9741.20120054

Cardiothoracic surgeon Paulo M. Pêgo-Fernandes receives Incentive Award in Science and Technology for the SUS - 2011 On April 16 in Brasilia-DF, Dr. Paulo M. Pêgo-Fernandes, associate professor, School of Medicine, University of Sao Paulo and coordinator of the Group of Lung Transplantation, Heart Institute of HC-FMUSP received the Incentive Award in Science and Technology for the SUS 2011 (Fig. 1). This award, in its 10th edition, an initiative of the Department of Science and Technology Secretariat for Science, Technology and Strategic Inputs of the Ministry of Health (Decit / SCTIE / MS), aims to provide recognition to the researcher in health care for its role in social and economic development in the country. The award is divided into five categories: Doctoral Thesis, Dissertation, Scientific Paper Published; Monograph Specialization or Residence, and Access to Health System, a new category instituted in commemoration of 10 years of the Prize. Professor Paulo received an honorable mention in the category Scientific Paper Published for his work “Evaluation and pulmonary reconditioning ex vivo”, published in the Brazilian Journal of Cardiovascular Surgery 2010;25(4):4416 [1], which has as authors: Paulo Manuel Pêgo-Fernandes, Alessandro Wasum Mariani, Israel Lopes de Medeiros, Artur Eugênio de Azevedo Pereira, Flávio Guimarães Fernandes, Fernando do Valle Unterpertinger, Mauro Canzian and Fabio Biscegli Jatene. That paper describes the method of ex vivo lung perfusion, developed initially for reconditioning of lungs rejected for transplantation. With this technique, it is expected that the number of lung transplants increase by about 50%, reducing the time on waiting list, which currently is 18 to 24 months to less than 12 months, thus reducing mortality during waiting for a transplant. 338

RBCCV 44205-1391

The ceremony of awards, held during the meeting with the Scientific Community 2012: Science, Technology and Innovation Management in National Development Project, was attended by the Minister of Health, Alexandre Padilha, the Minister of Science and Technology, Marco Antonio Raupp, the Secretary of Science, Technology and Strategic Inputs, Carlos Gabrois Gadelha, and the Director of the Department of Science and Technology, Jailson de Barros Correia. REFERENCE 1. Pêgo-Fernandes PM, Mariani AW, Medeiros IL, Pereira AEA, Fernandes FG, Unterpertinger FV, et al. Avaliação e recondicionamento pulmonar ex vivo. Rev Bras Cir Cardiovasc. 2010;25(4):441-6.

Fig.1 - From left to right: President of the Oswaldo Cruz Foundation (FIOCRUZ), Paulo Gadelha; Vice President of ABRASCO Brazilian Association of Post-Graduate in Collective Health, Luiz Eugênio Portela Fernandes de Souza; Dr. Paulo Pêgo-Fernandes and Health Minister Alexandre Padilha


Rev Bras Cir Cardiovasc 2012;27(2):339

Reviewers BJCVS 27.2 From this number, Revista Brasileira de Cirurgia Cardiovascular/ Brazilian Journal of Cardiovascular Surgery (RBCCV / BJCVS) will announce, as it reads below, the names of the reviewers of articles published in each edition. We seek, therefore, continue to value the work of dilettantes scientists, essential for the BJCVS maintain its high scientific standards, with increasing effect, as demonstrated by the growth of our Impact Factor.

Domingo Braile Editor-in-Chief RBCCV

Bruno Botelho Pinheiro

Miguel Angel Maluf

Carlos Manuel de Almeida Brandão

Moise Dalva

Edmo Atique Gabriel

Orlando Petrucci

Fabio Antonio Gaiotto

Otoni Moreira Gomes

Fabio Papa Taniguchi

Pablo Maria Alberto Pomerantzeff

Francisco Costa

Paulo Paredes Paulista

Frederico Pires de Vasconcelos Silva

Pedro Paulo Martins de Oliveira

João Carlos Ferreira Leal

Reinaldo Wilson Vieira

João Galantier

Ricardo de Carvalho Lima

José Glauco Lobo Filho

Rodolfo A. Neirotti

Karlos Alexandre de Sousa Vilarinho

Rubens Santana Thevenard

Lindemberg da Mota Silveira Filho

Stevan Krieger Martins

Luiz Augusto Ferreira Lisboa

Ulisses Alexandre Croti

Luiz César Guarita-Souza

Vinicius José da Silva Nina

Michel Pompeu Barros de Oliveira Sá

Walter José Gomes

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SOCIEDADE BRASILEIRA DE CIRURGIA CARDIOVASCULAR BRAZILIAN SOCIETY OF CARDIOVASCULAR SURGERY E-mail: revista@sbccv.org.br Sites: www.scielo.br/rbccv www.rbccv.org.br


RBCCV em números 26 anos de circulação ininterrupta Fator de Impacto 1,239 Consultada por leitores de 74 países

www.rbccv.org.br www.scielo.br/rbccv www.bjcvs.org

793.234 acessos no site próprio (www.rbccv.org.br) em 2011 402.309 acessos no site da SciELO (www.scielo.br/rbccv) em 2011 3540 visitantes diariamente 380,97 gigabytes (GB) transferidos, média de 1,04 GB por dia 21.902.562 impressões de páginas em 2011 (requisição do navegador de um visitante para uma página web que possa ser exibida), média diária de 60.007,02. Presente em nas bases de dados Lilacs, Scielo, Latindex, Index Copernicus Scopus, PubMed, Thomson Scientific (ISI), Google Scholar

Fig.1 – Número de acessos ao site da RBCCV em 2011

Fig. 2 – Transferência de bytes no site da RBCCV durante 2011

Fig. 3 – Número de impressões de páginas da RBCCV em 2011



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