High burden of new-onset AF (>10.87%) significantly increased MACE risk in AMI patients with LVEF ≥40% (HR 2.63), but not in those with LVEF <40%.
Does high new-onset atrial fibrillation burden increase major adverse cardiovascular events in acute myocardial infarction patients stratified by left ventricular ejection fraction?
High new-onset atrial fibrillation burden independently predicts adverse cardiovascular outcomes in AMI patients with preserved or mildly reduced LVEF (≥40%), but not in those with reduced LVEF (<40%).
Abstract Background Acute myocardial infarction (AMI) exhibits left ventricular ejection fraction (LVEF)- stratified prognosis with poorly characterized determinants, underscoring risk stratification gaps for ejection fraction-specific early interventions. Purpose To investigate the prognostic implication of New-Onset Atrial Fibrillation (NOAF)-burden in AMI patients across LVEF categories. Methods This multicenter retrospective analysis consecutively included AMI participants without prior atrial fibrillation (AF) who developed first documented AF during hospitalization from 2014 to 2022. Post‑MI NOAF patients were classified as either AMIrEF (EF 40%) or AMIpEF (EF ≥ 40%) and further stratified by an AF burden cutoff of 10.87%. The primary endpoint was major adverse cardiovascular events (MACE), comprising cardiovascular death and heart failure (HF) hospitalization. Secondary endpoints were cardiovascular death, HF rehospitalization and ischeamic stroke. Results Among 812 patients, 644 (79.3%) had baseline LVEF data, of whom 178 (27.6%) were classified as AMIrEF group and 466 (72.4%) as AMIpEF group. 248 (38.5%) had high AF burden (10.87%) during hospitalization. Over a 4.2-year median follow-up, MACE incidence was 18.9 and 23.0 per 100 person-years in low- and high-burden AMIrEF patients, and 7.2 and 17.5 in AMIpEF patients, respectively. After adjustment for confounders, high-burden NOAF was significantly associated with increased MACE in AMIpEF patients hazard ratio (HR): 2.63, 95% confidence interval (CI): 1.82-3.78 but not in AMIrEF HR: 0.78, 95% CI: 0.48-1.26. Propensity score-matched analyses yielded concordant results 1.08 (0.66-1.77) for AMIrEF and 2.45 (1.75-3.45) for AMIpEF. Similar results were found for CV death and HF rehospitalization after full adjustment. In addition, no statistically significant association was observed between AF burden and stroke outcomes in either the AMIrEF or AMIpEF cohort after propensity score matching. Conclusion Nearly 40% of patients had a high AF burden, with comparable proportions observed in both the AMIrEF and AMIpEF. High NOAF burden independently predicts adverse cardiovascular outcomes in AMIpEF patients, necessitating optimized screening for this high-risk group.Graphical abstract Table.Long-Term clinical outcomes
Fang et al. (2025) studied this question. High burden of new-onset AF (>10.87%) significantly increased MACE risk in AMI patients with LVEF ≥40% (HR 2.63), but not in those with LVEF <40%.