Coronary artery embolism (CE) is recognized as an important non-atherosclerotic cause of acute myocardial infarction. Its prevalence, clinical features, and prognosis remain unclear.

We studied 1232 consecutive patients who presented with de novo acute myocardial infarction between 2006 and 2015. CE was diagnosed based on criteria encompassing clinical, angiographic, and other imaging findings including intravascular imaging. The prevalence of CE was 4.3% (n=53), including 12 patients (22.6% of cases) with multivessel CE. In comparison with the non-CE group, age and coronary risks factors except smoking (P=0.03) were not significantly different in the CE group. PCI procedures was characterized by a distal coronary occlusion in 33 patients (62.2%), a more frequent GP2b3a inhibitors use (62.2% vs. 37.7%, P<0.001) but lower angioplasty requiring balloon and/or stent rate in CE group (54.7% vs. 45.2%, P<0.001). CE group was characterized by a lower ST segment resolution post-MI and worse postprocedural TIMI flow grade but no significant difference in left ventricular ejection fraction were seen between the two groups. The most frequent underlying disease was atrial fibrillation (n=15, 28.3% of cases) followed by intracardiac tumor (n=3) and endocarditis (n=4) whereas malignancy and antiphospholipid syndrome represented two major cause of hypercoagulable state (n=15) leading also to CE. However, 14 patients (26% of cases) had no identified cause of CE. During a median follow-up of 54 months, no CE and thromboembolism was noted. Kaplan-Meier curves of event free survival (all-cause death and recurrent myocardial infarction) showed that CE group had a poorer prognosis (Log-rank test P<0.004) mainly influenced by neoplasia and endocarditis (Fig. 1).

Patients with CE represent a high-risk subgroup of patients and their prognosis is mainly influenced by underlying cause.