Long-Term Outcomes of Mitral Valve Repair with Limited Resection in Active Endocarditis.

Background: Current guidelines recommend mitral valve (MV) repair over replacement for active native valve endocarditis. However, traditional techniques involving radical debridement and prosthetic patch reconstruction may limit repair feasibility and long-term durability. This study evaluates the long-term clinical outcomes of an alternative approach utilizing a limited resection and non-patch technique in patients presenting with active native MV endocarditis. Methods: Consecutive patients with definite active native MV endocarditis who underwent surgical treatment between January 2016 and December 2021 were retrospectively reviewed. From this cohort, all patients managed with MV repair using a limited resection strategy without patch plasty were selected and compared to patients undergoing MV replacement after radical resection. The prespecified primary endpoints were overall mortality, the incidence of recurrent endocarditis, and the rate of reoperation during five-year follow-up. The Cox proportional hazards model was used to identify predictors of overall mortality and adverse events (composite of death, recurrence, and/or reoperation). Results: Out of 128 patients with active native MV endocarditis, 75 patients successfully underwent MV repair via the limited resection and non-patch technique and 53 patients received MV replacement. Five-year mortality rates were 43% in the repair group and 52% in the replacement group, p = 0.31. Six patients developed recurrent endocarditis in the repair group, while one patient developed it in the replacement group. Reoperation was necessary in five cases in the repair group, while one patient in the replacement group required reoperation due to paravalvular leakage. Surgical strategy was not associated with mortality or adverse events. Staphylococcal endocarditis was a strong predictor of overall mortality (HR: 2.2 (1.3-3.7)) and adverse events (HR: 2.2 (1.0-4.9)). Conclusions: A limited resection approach for active native MV endocarditis appears to be a feasible surgical strategy to enhance valve reparability, particularly in non-staphylococcal cases. Conversely, staphylococcal endocarditis remains a potent independent risk factor associated with increased mortality and adverse events.