Influence of Atrial Fibrillation on Outcomes in Patients Who Underwent Primary Percutaneous Coronary Intervention for ST-Segment Elevation Myocardial Infarction.

Atrial fibrillation (AF) is a common co-morbidity among patients presenting with acute ST-segment elevation myocardial infarction (STEMI). Previously, small studies have reported an association between AF and poorer outcomes among patients with STEMI. We performed this study to investigate the impact of AF on in-hospital outcomes in patients with STEMI treated with primary percutaneous coronary intervention (PPCI) using a large national database. The study population constituted of patients 18 years and older with a primary discharge diagnosis of STEMI and who underwent PPCI. Using a 2:1 matching protocol, matched groups of patients with AF (N = 24,680) and without (N = 49,198) were developed. Among 1,493,859 patients with STEMI who underwent PPCI, 129,354 patients (8.7%) had AF. In the propensity-matched cohort, adjusted in-hospital mortality was significantly higher for patients with AF compared with patients with no AF (10.3% vs 9.4%) (adjusted odds ratio [OR] 1.10; confidence interval [CI] 1.06 to 1.16; p <0.0001). Patients with AF were also at higher risk of heart failure, cardiogenic shock, acute stroke, acute kidney injury, vascular complications, need for blood transfusion, and a composite outcome of gastrointestinal and retroperitoneal bleeding. Patients with AF were less likely to be treated with drug-eluting stent compared with patients without AF (51.4% vs 56.6%) (adjusted OR 0.81; CI 0.79 to 0.84; p <0.001). Among patients presenting with STEMI and who underwent PPCI, AF is present in about 8% of patients. In a propensity-matched analysis using a large national database, AF was found to be independently associated with a higher risk of in-hospital mortality and of other complications in these patients.