Outcomes and predictors of patients with moderate or severe functional mitral regurgitation and nonischemic dilated cardiomyopathy

BACKGROUND: Patients with functional mitral regurgitation (FMR) and nonischemic dilated cardiomyopathy (DCM) are associated with high mortality. OBJECTIVES: Our study aimed to compare the clinical outcomes between different treatment strategies and identify predictors associated with the adverse outcomes. METHODS: A total of 112 patients with moderate or severe FMR and nonischaemic DCM were included in our study. The primary composite outcome was all‐cause death or unplanned hospitalization for heart failure. The secondary outcomes were individual components of the primary outcome and the cardiovascular death. RESULTS: In this study, the primary composite outcome occurred in 26 patients (44.8%) in mitral valve repair (MVr) group and 37 patients (68.5%) in medical group (hazard ratio [HR], 0.28; 95% confidence interval [CI], 0.14–0.55; p < .001). The 1‐, 3‐, and 5‐year survival rates for patients with MVr were 96.6%, 91.8%, and 77.4%, respectively, which were significantly higher than that of medical group: 81.2%, 71.9%, and 65.1%, respectively (HR, 0.32; 95% CI, 0.12–0.87; p = .03). Left ventricular ejection fraction (LVEF) < 41.5% (p < .001) and atrial fibrillation (p = .02) were independently associated with the primary outcome. LVEF < 41.5% (p = .007), renal insufficiency (p = .003), and left ventricular end‐diastolic diameter > 66.5 mm (p < .001) were independently associated with heightened risk for all‐cause death. CONCLUSION: Compared with medical therapy, MVr was associated with a better prognosis in patients with moderate or severe FMR and nonischemic DCM. We observed that LVEF < 41.5% was the only independent predictor of the primary outcome and all individual components of secondary outcomes.