Coronary Embolism among Patients with ST‐Segment–Elevation Myocardial Infarction and Atrial Fibrillation: an Underrecognized but Deadly Association

Background The prevalence and impact of coronary emboli (CE) in patients with ST‐segment–elevation myocardial infarction (STEMI) and atrial fibrillation (AF) have not been specifically studied. The objective was to describe the clinical characteristics and outcomes of patients with AF and CE in a large series of patients with STEMI. Methods and Results We investigated 2292 consecutive patients with STEMI and among them 225 patients with AF: 46 patients with a STEMI related to CE (group A) and 179 patients with a STEMI related to an atherosclerotic cause (group B). Compared with the 2067 patients without AF and CE (group C), patients with AF and CE were older (73 versus 59 years, P <0.05), more likely to be female (43% versus 22%, P <0.05), and presented more frequently with cardiogenic shock at admission (26% versus 9%, P <0.05). The baseline characteristics of patients with AF (group A versus B) did not differ significantly according to STEMI pathogenesis. In the unadjusted analysis, the 45‐day mortality was higher in patients with CE and AF (group A versus group C: 20% versus 4%; P <0.05 and group A versus group B: 20% versus 8%, P =not significant); this trend persisted at 2‐year follow‐up (group A versus group C: 24% versus 6%; P <0.05 and group A versus group B: 24% versus 17%, P =not significant). After stabilized inverse exposure probability weighting adjustment, a higher 45‐day mortality rate was confirmed in patients with CE and AF (group A versus group C: 18% versus 5%, P <0.05). Conclusions In patients presenting with STEMI and AF, CE was associated with excess early mortality. Registration URL: clinicaltrials.gov . Identifier: NCT05679843.