Long-Term Outcomes of Contemporary Surgical Repair for Degenerative Mitral Regurgitation

Background: There are limited published reports about the long-term outcomes of contemporary surgical mitral repair series for degenerative mitral regurgitation performed at a high-volume center. Objectives: The aim of this study is to report independently adjudicated long-term results of contemporary mitral repair surgery performed at a high-volume center. Methods: A retrospective study was conducted on 3,317 patients who underwent surgical mitral repair for degenerative mitral regurgitation at a tertiary care center between January 1, 2008 and December 31, 2017. Follow-up data, focusing on survival, reinterventions, and heart failure rehospitalizations were adjudicated and analyzed by the Italian National Agency for Regional Healthcare Services. Echocardiographic assessments during follow-up were not included. Complete (100%) data linkage was achieved. Results: The median age of the patients was 57 years, and 68.56% were men. The overall in-hospital mortality was 0.48% (16 of 3,317) for all cases and 0.21% (5 of 2,399) in isolated mitral valve repair. The 10-year survival was 89.65% (95% CI: 88.75%-90.55%), independently associated with preoperative symptoms and anterior leaflet disease. Freedom from reoperation was 96.63% (95% CI: 95.63%-97.63%) at 10 years. Anterior leaflet disease, a second run of cardiopulmonary bypass, and more than mild mitral regurgitation at discharge were associated with increased risk of reoperation. Finally, 10-year freedom from rehospitalization for heart failure was 92.24% (95% CI: 90.62%-93.86%), with age, prior hospitalization for heart failure, preoperative symptoms, and anterior leaflet disease identified as independent risk factors. Conclusions: This contemporary series provides further data on the low in-hospital mortality and excellent long-term outcomes of surgical mitral repair when performed in a high-volume center. Preoperative symptoms are associated with worse outcomes. Isolated anterior leaflet disease increases the risk of reoperation, heart failure rehospitalization, and late mortality compared to posterior or bileaflets pathology.