Functional Mitral Regurgitation at Discharge and Outcomes in Patients Hospitalized for Acute Decompensated Heart Failure with a Preserved or Reduced Ejection Fraction

Abstract Aims The relationship between functional mitral regurgitation (FMR), left ventricular ejection fraction (EF), and outcomes is unclear in acute decompensated heart failure (HF) patients. The aim of this study was to evaluate the relationship between FMR and post-discharge outcomes in HF patients with a preserved or reduced EF. Methods and results Of the 4842 patients enrolled in the Acute Decompensated Heart Failure Syndromes (ATTEND) registry, 3357 patients were evaluated to assess the association among FMR (none, mild, or moderate/severe) at discharge, a preserved or reduced EF, and the primary endpoint (all-cause mortality and readmission for HF). The median follow-up period after discharge was 530 (387–800) days. According to multivariate analysis, patients with either mild FMR or moderate/severe FMR from the preserved EF group had a significantly higher risk of reaching the endpoint than patients without FMR [hazard ratio (HR) 1.40; 95% confidence interval (CI) 1.14–1.72; P = 0.001 and HR 1.40; 95% CI 1.09–1.81; P = 0.009, respectively]. In the reduced EF group, patients with moderate or severe FMR had a significantly higher risk relative to patients without FMR (HR 1.41; 95% CI 1.07–1.86; P = 0.015), but there was no significant association of mild FMR with the risk of reaching the endpoint (HR 1.09; 95% CI 0.84–1.42; P = 0.510). Conclusion Our findings demonstrate that even mild FMR is associated with an increased risk of adverse outcomes in HF patients with a preserved EF, while moderate or severe FMR (but not mild FMR) is associated with adverse outcomes in HF patients with a reduced EF.