Become a Sherlock Homes in ECG(Series 1

Series 1 :

JOURNAL OF THE INDIAN MEDICAL ASSOCIATION, VOL 118, NO 06, JUNE 2020

Become a Sherlock Homes in ECG

M Chenniappan 1

ECG

Clue : ”Clock shows 30 seconds past six thirty”

This is the ECG of 60 years Male smoker.

Questions :

1. What is the diagnosis? 2. Why is this clue? 3. What are the other names of this sign? 4. What is the practical implication?

Answers :

1. This ECG shows very small P, QRS, T complexes in Lead I. This usually happens in patients with COPD.

2. The clue is sixty seconds past six thirty sign is given because, p axis, QRS axis and T axis all in the same line towards lead avF. Because all the three complexes’ axis is going towards aVF , LI becomes equiphasic zone of these complexes and because of this, P QRS and T waves are very small in LI. If you imagine axis diagnosis as a clock, when all waves axis is towards avF, it is like the time of sixty seconds past six thirty in the clock. That is why clue is given

3. Other names for this ECG are “Schamroth sign” or “Lead I sign”

4. The practical implication is that whenever ECG in a patient with COPD shows Right Axis deviation and RA,RV involvement indicates bad prognosis due to associated pulmonary hypertension and corpulmonale.

This sign indicates vertical heart due to compressed heart due hyperinflated lungs.

LI

1 Adjunct Professor,Tamilnadu Dr MGR Medical University, Tamil Nadu; Senior consultant cardiologist, Ramakrishna Medical Centre,Apollo Speciality Hospital, Trichy

50

Avf (P,QRS,T Axis)

Fig. 1 Sixty seconds past six thirty