Should we establish a new protocol for the treatment of peripartum myocardial infarction?

Peripartum myocardial infarction is a rare event that is associated with high mortality rates. The differential diagnosis includes coronary artery dissection, coronary artery thrombosis, vascular spasm, and stenosis. Our evaluation of 2 cases over a 5-year time period has led to a hypothesis that peripartum myocardial infarction is an immune-mediated event secondary to coronary endothelial sensitization by fetal antigen. In our patients, we supplemented standard medical therapy with immunotherapy consisting of corticosteroids, plasmapheresis, and intravenous immunoglobulin. Herein, we present our most recent case-that of a 29-year-old black woman (gravida V, para IV), 2 weeks postpartum with no relevant medical history. She presented with a 1-week history of chest pain. Initial electrocardiographic and cardiac biomarkers were consistent with acute coronary syndrome. Echocardiography revealed reduced systolic function with inferior-wall hypokinesis. Angiography revealed diffuse disease with occlusion of the left anterior descending coronary artery not amenable to revascularization. We were successful in treating the myocardial infarction without the use of catheter-based interventions, by modifying the immunologic abnormalities. Two cases do not make a protocol. Yet we believe that this case and our earlier case lend credence to the hypothesis that peripartum myocardial infarction arises from sensitization by fetal antigens. This concept and the immune-modifying treatment protocol that we propose might also assist in understanding and treating other inflammatory-disease states such as peripartum cardiomyopathy and standard acute myocardial infarction. All of this warrants further investigation.