ObjectiveIn elderly patients, the benefit of surgical correction of severe mitral regurgitation (MR) may not be greater than the operative risk. This study sought to compare the long-term clinical outcomes between initial surgery and conservative management in elderly patients (≥70 years of age) with severe MR.MethodsWe prospectively evaluated 157 consecutive patients (75 men, 74±4 years of age) with severe degenerative MR and mild symptoms. Mitral valve surgery was performed on 79 (initial surgery group), whereas the conservative strategy was chosen for 78 patients (conservative management group). We compared the overall and cardiac mortality and cardiac event between strategies in the overall and propensity-matched cohort (46 pairs).ResultsDuring the median follow-up of 5.4 years, overall death occurred less in the initial surgery group (16 vs 37 patients). This group showed reduced cardiac mortality (HR 0.31; 95% CI 0.13 to 0.73; p=0.007), overall mortality (HR 0.39; 95% CI 0.21 to 0.74; p=0.004) and cardiac event (HR 0.26; 95% CI 0.13 to 0.53; p<0.001). A significant reduction in cardiac mortality (HR 0.18; 95% CI 0.05 to 0.63; p=0.007), overall mortality (HR 0.36; 95% CI 0.15 to 0.86; p=0.022) and cardiac event (HR 0.20; 95% CI 0.07 to 0.52; p=0.001) in the initial surgery group was also observed in the propensity-matched cohort.ConclusionsIn elderly patients with severe degenerative MR and mild symptoms, initial surgical strategy was associated with significant long-term reductions in cardiac and overall mortality compared with conservative management.