Mechanisms of Recurrent Regurgitation After Valve Repair for Prolapsed Mitral Valve Disease

Background. We assessed mitral valve (MV) function using serial echocardiography as an indicator of the durability of MV repair. The aim of this study was to analyze the mechanisms of recurrent regurgitation after MV repair for degenerative disease. Methods. From 1991 to 2007, 736 patients had valve repair for mitral regurgitation caused by leaflet prolapse: 346 patients had posterior and 390 had anterior leaflet prolapse. The mean age was 54.6 +/- 14.6 years, with 495 males. The durability and mechanisms of recurrent regurgitation were evaluated by the findings of echocardiography and reoperation. Follow-up and late echocardiography averaged 5.7 +/- 3.9 and 5.1 +/- 3.6 years, respectively. Results. Survival was 91.9% +/- 1.5% at 10 years. Freedom from reoperation and moderate or severe regurgitation at 10 years were 91.2% +/- 1.7% and 84.5% +/- 2.1%, respectively. Reoperations were performed for recurrent regurgitation in 29 patients, hemolysis in 5, and endocarditis in 1. Based on the findings of reoperation, the mechanisms of repair failure were procedure related in 9 (25.7%), valve related in 25 (71.4%), and unknown in 1. Late echocardiography revealed none to trivial regurgitation in 511 patients, mild in 153, moderate in 26, and severe in 40. Anterior leaflet prolapse, preoperative atrial fibrillation, and no use of annuloplasty ring were independent predictors of recurrent regurgitation. The main causes of moderate or severe regurgitation were leaflet thickening in 34 patients, leaflet prolapse in 20, dehiscence in 10, and unknown in 2. Conclusions. The main mechanism of recurrent regurgitation after MV repair is progressive degeneration that is characterized by leaflet thickening and prolapse, especially in patients with anterior leaflet prolapse. (Ann Thorac Surg 2011; 91: 1433-9) (C) 2011 by The Society of Thoracic Surgeons