Background:This study investigated the consequences of recurrent mitral regurgitation (MR) after mitral valve (MV) repair in patients with degenerative MR and risk factors for recurrence.

Methods and Results:From January 1990 to December 2015, 792 patients underwent MV repair due to degenerative MR. Recurrent MR was defined as moderate-to-severe MR on follow-up echocardiography. Mean follow-up duration was 8.71±5.58 years. During the follow-up period, MR recurred in 133 (16.8%) patients, and the MR recurrence-free rate at 20 years was 77.5±2.0%. In the recurrence group, the degree of MR decreased in 8 (6.0%) patients and was aggravated in 46 (34.6%) patients. Recurrent MR was associated with increased mortality and adverse left ventricular (LV) remodeling. Independent risk factors for MR recurrence were MV repair performed before 2000, preoperative atrial fibrillation, high LV end-diastolic dimension (LVEDD), prolapse of the isolated anterior leaflet or multiple segments, and absence of ring annuloplasty. Predictors of MR progression were high LVEDD and repair without artificial chordae implantation.

Conclusions:Recurrent MR after MV repair in patients with degenerative MR showed a tendency to progress and was associated with increased mortality and adverse LV remodeling. Early referral for MV repair before development of atrial fibrillation and LV enlargement may reduce the risk of MR recurrence. Moreover, artificial chordae implantation and ring annuloplasty may assure the long-term durability of MV repair.