Pregnancy and Coronary Ischemia Figure 2: Flowchart for Management of Acute Coronary Syndrome Presentation in a Pregnant Woman
Pregnant woman with ACS
Immediate consultation with OB and cardiology transfer to tertiary care center if stable/possible
Invasive management
Medical management
Aspirin, heparin, clopidogrel
Normal
Conservative management
TIMI flow 2-3 and stable
Angiogram by experienced operator to minimize radiation
Atherosclerosis
SCAD
TIMI flow 0-1 and unstable
thrombus
Revascularize if appropriate. Consider bare-metal stent to minimize DAPT
Revascularize via PCI or consider CABG in high volume center
Inpatient monitoring for 5–7 days with cardiology consultation and follow-up with cardiology pre and post delivery ACS = acute coronary syndrome; CABG = coronary artery bypass grafting; DAPT = dual antiplatelet therapy; OB = obestetrics; PCI = percutaneous coronary intervention; SCAD = spontaneous coronary artery dissection; TIMI = thrombolysis in myocardial infarction.
Additionally, excess estrogen and progesterone promote changes in the arterial wall, which could contribute to medial breakdown.39 The significant increase in blood volume, cardiac output, and abrupt hemodynamic stresses in delivery and postpartum have also been hypothesized to contribute to an increased chance at dissection.40 Pregnancy is a risk factor for SCAD, with a majority of the cases occurring in the third trimester or post-partum period. Additionally, case reports reveal pregnancy-associated SCAD as more frequent in women >30 years of age and in multiparous women.20 Fibromuscular dysplasia (FMD) is associated with and may be a causal factor in SCAD, although the prevalence of FMD in pregnancy-associated SCAD is unknown.41–43
Thromboembolic Thrombophilia in pregnancy is more often associated with VTE than arterial thromboembolism.44 Paradoxical embolus is an unusual cause of MI, and is more commonly associated with cryptogenic stroke.45,46 Literature on pregnancy and paradoxical embolus leading to cardiac ischemia remains limited to case reports. In two instances, the patients were documented to each have a patent foramen ovale (PFO) along with a Factor V Leiden mutation.47,48 Coronary thrombosis without atherosclerotic disease causing ischemia is rare, however, 45 % of women with pregnancies complicated by acute MIs were smokers.40
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Cigarette smoking in pregnancy is associated with increased platelet activity, further contributing to a pro-coagulant cascade.49
Atherosclerosis Atherosclerotic heart disease, or coronary artery disease (CAD), is responsible for the largest proportion of CVD among women and men, and for nearly one-third of all deaths worldwide.50 Age is strongly associated with CAD, and as more women delay childbearing to later years the number of ischemic events in pregnant women is also expected to increase.51,52 A recent study evaluated 43 women with prior MI or a history of ACS and 50 pregnancies, over a time span of 7 years and across six academic medical centers. Women with pre-existing CAD and prior MI events were at a higher risk for coronary ischemic events with pregnancy, found to comprise five patients with one death, three ACS/MI episodes, and one case of heart failure. Established risk factors were present in 80 % of those patients, and 60 % had a history of cigarette smoking.22 Figure 2 is an algorithm for the management of the pregnant patient with ACS.
Risk Factors for Pregnancy-associated Coronary Ischemia It is difficult to ascribe risk factors to one etiology of coronary ischemia versus another due to low event rates. Additionally, since many studies
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