Outcomes of Degenerative Mitral Valve Repair Surgery for Anterior, Posterior, and Bileaflet Pathology

Background: Degenerative mitral valve disease involving anterior leaflet pathology is considered less favorable regarding durability of surgical repair than isolated posterior leaflet disease. We aimed to compare the outcomes of patients undergoing mitral valve repair for anterior, posterior, and bileaflet pathologies, and to investigate predictors for repair failure. Methods: Of the 760 consecutive patients with degenerative leaflet disease who underwent mitral valve repair, 485 (64%) had posterior, 223 (29%) had bileaflet, and 52 (7%) had anterior leaflet pathology. Mean age was 58 ± 12, 54 ± 14, and 58 ± 17 years, respectively (P = .001). Mean follow-up was 67 ± 47 months. Results: There was no in-hospital or 30-day mortality. Freedom from reoperation was 97%, 95%, and 92%, respectively, and there were 25 (5%), 9 (4%), and 1 (2%) late deaths in the posterior, bileaflet, and anterior groups, respectively (not significant). Late echocardiography revealed that 94%, 97%, and 96% of patients (posterior, bileaflet, and anterior groups respectively) were free from moderate-severe or severe mitral regurgitation (P = .375). Postoperative residual mild mitral regurgitation emerged as the strongest predictor for recurrent mitral regurgitation (grade 3/4) at follow-up (hazard ratio = 2.36; 95% confidence interval, 1.30-4.29; P = .005). Unlike patients with excess mitral tissue, among patients with fibroelastic deficiency or those who underwent major leaflet resection, the use of larger ring annuloplasty was associated with recurrent mitral regurgitation (hazard ratio = 1.31/ring size increment; P < .001). Conclusions: Mitral valve repair can be achieved with excellent early and intermediate results across all valve pathologies. Further studies are required to determine the potential long-term impact of the underlying pathology on the rate of recurrent mitral regurgitation.