Timing of valve repair for severe degenerative mitral regurgitation and long-term left ventricular function

Objectives: Current guidelines recommended surgery for patients with severe degenerative mitral regurgitation (MR) when specific left ventricular (LV) dimensions or ejection fraction (EF) are reached, based on previous postoperative survival studies. The aim of this study was to evaluate the incidence and predictors of long-term postoperative LV dysfunction, and investigate the preoperative parameters necessary to maintain or recover long-term LV function in the era of mitral valve (MV) repair. Methods: We retrospectively reviewed 473 consecutive patients undergoing MV repair for severe degenerative MR for whom both preoperative and 3-year postoperative echocardiographic data were available in our institution. Preoperative and 3-year postoperative echocardiographic data and clinical outcomes were evaluated. Results: Receiver operating characteristic analysis identified preoperative LVEF 63% or less (area under curve [AUC], 0.725; P < .001) and LV end-systolic dimension (ESD) 39 mm or greater (AUC, 0.724; P < .001) as cut-off values for predicting LVEF less than 50% 3 years after surgery. On multivariate analysis, both preoperative LVEF and LVESD were not significant predictors of 3-year postoperative LV dysfunction among patients with preoperative LVEF greater than 63% and LVESD less 39 mm, whereas preoperative LVESD (odds ratio [OR], 2.22; P = .004), higher age (OR, 1.03; P = .04), and atrial fibrillation (OR, 2.68; P = .01) were independent predictors among patients with preoperative LVEF 63% or less or LVESD 39 mm or greater. Conclusions: Early MV repair with LVEF greater than 63% and LVESD less than 39 mm preserved long-term postoperative LV function well, and smaller preoperative LVESD was associated with long-term LV function recovery, even in patients with preoperative LV dysfunction.