New-onset atrial fibrillation in patients with ST-elevation myocardial infarction

Abstract Background New-onset atrial fibrillation (NOAF) complicating ST-elevation myocardial infarction (STEMI) remains clinically challenging. Little is known regarding the long-term clinical impact of NOAF in the acute STEMI phase compared to a prior diagnosis of AF before the onset of STEMI. Methods We retrospectively reviewed consecutive patients undergoing percutaneous coronary intervention (PCI) for STEMI between May 2015 and September 2023. Patients were stratified based on NOAF diagnosis during the index-hospitalization vs. preexisting AF prior to the onset of STEMI. Long-term follow-up was obtained for stroke, major bleeding, or death. Results We analyzed 1327 consecutive patients undergoing PCI for STEMI. NOAF was detected in 117 patients (9%) and 69 patients (5%) had prior AF. Patients with NOAF and prior AF had similar baseline characteristics. NOAF patients were 65% males, with a mean age of 69 ± 13 years. All patients were treated with enoxaparin, but only 30% of patients with NOAF and 65% with prior AF were discharged with triple therapy, p0.05. During a median follow-up of 696 days, the rates of stroke were 11% in patients with NOAF compared to 6% (p= 0.03) in patients with prior AF. Major bleeding occurred in 7% vs. 9%, p= 0.59, and death in 19% vs. 22%, p= 0.25 of patients with NOAF vs. prior AF. Conclusion NOAF was detected in almost 1 out of 10 STEMI patients and was associated with a similar rate of major bleeding and death as in patients with prior AF. The risk of NOAF for stroke might be higher than that of prior AF. These finding warrant confirmation in larger data sets.Central illustration