Early surgery versus conventional treatment for asymptomatic severe mitral regurgitation: a propensity analysis

Objectives: This study sought to compare long-term outcomes of early surgery with a conventional treatment strategy in asymptomatic patients with severe mitral regurgitation (MR).

Background: The timing of surgery in asymptomatic severe MR remains controversial.

Methods: From 1996 to 2009, 610 consecutive asymptomatic patients (364 men, 50 ± 14 years of age) with severe degenerative MR and preserved left ventricular function were evaluated prospectively. Early surgery was performed on 235 patients, and the conventional treatment strategy was chosen for 375 patients. We compared overall mortality, cardiac mortality, and cardiac events (operative mortality, cardiac mortality, repeat surgery, and urgent admission due to heart failure) between the 2 treatment strategies in the propensity score-matched cohort.

Results: For the 207 propensity score-matched pairs, early surgery had a lower risk of cardiac mortality (hazard ratio [HR]: 0.109; 95% confidence interval [CI]: 0.014 to 0.836; p = 0.033) and cardiac events (HR: 0.216; 95% CI: 0.083 to 0.558; p = 0.002) than conventional treatment. On Cox proportional hazard model analysis, the risk of cardiac events was significantly lower in the early surgery group than in the conventional treatment group in patients aged 50 years of age and older (HR: 0.221; 95% CI: 0.086 to 0.567; p = 0.002), but not significantly different in those younger than 50 years of age (p = 0.20).

Conclusions: Compared with conservative management, early surgery is associated with significant long-term reductions of cardiac mortality and cardiac events in asymptomatic severe MR. These benefits were evident among patients age 50 years of age and older.