Postpartum myocardial infarction: association with primary coronary artery dissection

A 36-year-old woman presented with an acute myocardial infarction 2 weeks after the birth of her first child. The patient had smoked two packs of cigarettes a day for 12 years and had been taking bromocriptine to suppress lactation. While in the emergency room, the patient went into ventricular fibrillation, but defibrillation successfully restored sinus rhythm. Coronary angiography revealed several atherosclerotic lesions. The patient refused to undergo coronary artery bypass grafting, and she was discharged receiving medical therapy.

Forty-eight cases of postpartum myocardial infarction have previously been reported; the present case makes 49. In 41 cases a cardiac examination was performed, either on necroscopy or by angiography. Twenty-two (54%) of the 41 patients had occlusion related to primary coronary artery dissection, 11 (27%) had normal coronary arteries and presumed spasm, and only 6 (15%) had atherosclerosis-related coronary occlusion. The mortality rate was 39%, and surviving patients had significant cardiac limitation.

Postpartum myocardial infarction and coronary occlusion, when they do occur, are frequently caused by primary coronary artery dissection. Immediate recognition of this association may significantly reduce morbidity and mortality for these patients.