Myocardial infarction in pregnancy associated with a coronary artery thrombus

The case of a 36-year-old multigravid woman in whom acute myocardial infarction developed at five months post partum is described. Coronary angiography performed 11 days following myocardial infarction demonstrated a thrombus-like lesion in the coronary artery branch supplying the area of myocardial damage with no other evidence of coronary artery disease. This finding suggests that the development of a coronary artery thrombus is part of the mechanism of myocardial infarction in this case and may be relevant to explain other, similar cases where the phenomenon of angiographically normal coronary arteries following myocardial infarction has been described. The mechanism leading to the development of a coronary thrombus in pregnancy is obscure, but may be similar to other clotting abnormalities complicating the third trimester and puerperium. (Arch Intern Med139:1046-1047, 1979)