Long-term survival in asymptomatic patients with severe degenerative mitral regurgitation: a propensity score-based comparison between an early surgical strategy and a conservative treatment approach.

Abstract

The management of asymptomatic severe mitral regurgitation remains controversial. The aim of the study was to assess the long-term survival, incidence of cardiac complications, factors that predict outcome, and effect of mitral surgery on the long-term prognosis of patients with asymptomatic severe mitral regurgitation amenable to valve repair. One hundred ninety-two asymptomatic patients (mean age, 63 +/- 13 years) with severe degenerative mitral regurgitation diagnosed by 2-dimensional echocardiography between 1990 and 2001 were prospectively followed for a median of 8.5 years. Overall, cardiovascular, and event-free survival was evaluated in 2 groups of patients: a "conservative approach" group (n = 67) and an "early surgery" group (n = 125). Outcomes were also analyzed among patients with atrial fibrillation, pulmonary hypertension, or both, as well as in patients free of any mitral regurgitation complications. In the whole population, 10-year overall survival was significantly lower with the conservative approach than early surgery (50% +/- 7% vs 86% +/- 4%, log-rank < 0.0001). Similar results were obtained in the subgroups with atrial fibrillation and/or pulmonary hypertension. The 10-year propensity-matched score-adjusted hazards ratio for overall mortality, cardiac mortality, and cardiovascular events for the conservative treatment were 5.21, 4.83, and 4.40, respectively. Our results show that the outcome of asymptomatic patients with severe degenerative mitral regurgitation is better with an early surgical approach rather than a more conservative treatment strategy.