Prognostic Significance of New-Onset Atrial Fibrillation in Heart Failure with Preserved, Mid-Range, and Reduced Ejection Fraction Following Acute Myocardial Infarction: Data from the NOAFCAMI-SH Registry.

Purpose: The prognostic impact of new-onset atrial fibrillation (NOAF) among different heart failure (HF) subtypes including HF with preserved (HFpEF, ejection fraction [EF] ≥50%), mid-range (HFmrEF, EF 40%~49%), and reduced (HFrEF, EF <40%) EF following acute myocardial infarction (AMI) remains unclear. We aimed to investigate the incidence and prognostic implication of post-MI NOAF across HF subtypes.

Patients And Methods: We included 1413 patients with post-MI HF (743 with HFpEF, 342 with HFmrEF and 328 with HFrEF) between February 2014 and March 2018. NOAF was considered as patients without a preexisting AF who developed AF during the AMI hospitalization. The primary endpoint was all-cause mortality.

Results: Of 1413 patients (mean age 66.8 ± 12.6 years, 72.9% men) analyzed, 200 (14.2%) developed post-MI NOAF. Patients with HFrEF were more likely to experience NOAF compared to those with HFmrEF or HFrEF (18.9%, 13.7% and 12.2% in HFrEF, HFmrEF and HFpEF, respectively; p for trend = 0.006). During a median follow-up of 28.5 months, 192 patients died (70 with HFrEF, 35 with HFmrEF and 87 with HFpEF) and 195 patients experienced HF rehospitalization (79 with HFrEF, 37 with HFmrEF and 79 with HFpEF). After multivariable adjustment, NOAF was independently associated with all-cause mortality (hazard ratio [HR]: 1.79, 95% confidence interval [CI]: 1.03-3.12) only in the HFrEF group compared to sinus rhythm (SR), whereas an increased risk of HF rehospitalization was found in all HF subtypes, particularly in HFmrEF (HR: 5.08, 95% CI: 2.29-11.25) and HFpEF (HR: 2.83 95% CI: 1.64-4.90).

Conclusion: In patients with post-MI HF, NOAF carried a worse prognosis for all-cause death in the HFrEF group and for HF rehospitalization in all HF subtypes.