Efficacy of spironolactone in patients with heart failure with preserved ejection fraction following acute myocardial infarction: A multicenter retrospective cohort analysis

BACKGROUND: Heart failure with preserved ejection fraction (HFpEF) following acute myocardial infarction is common, yet evidence-based pharmacotherapy remains limited. This study aims to evaluate the efficacy of spironolactone among patients with HFpEF following acute myocardial infarction. METHODS: We conducted a multicenter retrospective cohort study using data from 82 hospitals across China between January 2010 and March 2024. Patients were stratified into spironolactone users versus non-users. Propensity score matching (PSM) was performed to balance baseline covariates. The primary endpoint was a composite of 1-year heart failure rehospitalization or cardiac death. Time-to-event outcomes were analyzed using Kaplan-Meier curves with log-rank tests. Cox proportional hazards models with cluster-robust variance estimation were used to estimate hazard ratios (HRs). Restricted mean survival time (RMST) analysis was applied to assess survival differences when the proportional hazards assumption was violated. Prespecified subgroup analyses were conducted by age (