Coronary Embolism Among ST-Segment-Elevation Myocardial Infarction Patients: Mechanisms and Management.

Abstract

Coronary artery embolism (CE) is recognized as an important nonatherosclerotic cause of ST-segment-elevation myocardial infarction. The objective was to describe clinical characteristics and long-term outcomes and to identify risks factors of CE in a large consecutive series of ST-segment-elevation myocardial infarction patients. We studied 1232 consecutive patients who presented with de novo ST-segment-elevation myocardial infarction. CE was diagnosed based on criteria encompassing clinical, angiographic, and diagnostic imaging findings. A total of 53 patients were identified in the CE group including 12 (22.6%) patients with multisites CE and 9 patients with other extracoronary localization. Compared with the non-CE group, age and coronary risks factors were not significantly different in the CE group except for smoking (P=0.03) and body mass index (P<0.001). Interventional coronary procedures were characterized by a higher use of glycoprotein IIb/IIIa inhibitors (P<0.001) and lower use of angioplasty (P<0.001) in the CE group. The most frequent underlying cardiac diseases were atrial fibrillation (n=15, 28.3%) followed by dilated cardiomyopathy (n=5), endocarditis (n=4), and intracardiac tumor (n=3), whereas among systemic diseases, malignancy (n=8) and systemic autoimmune disease or antiphospholipid syndrome (n=4) were present. No etiopathological mechanisms could be identified in 14 patients (26.4%). Coronary embolism was associated with a higher risk of death (crude hazard ratio, 4.87; 95% confidence interval, 2.52-9.39; P<0.0001). Etiopathogenesis of ST-segment-elevation myocardial infarction secondary to CE is diverse ranging from cardiac to systemic disease, and patient long-term survival is worse than expected according to the baseline cardiovascular risk.