Abstract
BACKGROUND: The optimal surgical strategy for mitral valve (MV) infective endocarditis (IE) remains uncertain. Although valve repair is increasingly advocated, MV replacement is frequently performed, and robust data comparing long-term outcomes between approaches are limited. We evaluated long-term survival following MV repair vs replacement in patients with IE-related mitral regurgitation. METHODS: We retrospectively analysed 88 consecutive patients who underwent MV surgery for IE-associated mitral regurgitation at St George's Hospital NHS Foundation Trust, UK, between June 2011 and May 2025. Long-term all-cause mortality was assessed using Kaplan-Meier survival analysis. Multivariable logistic regression identified independent predictors of mortality, and model discrimination was evaluated using the area under the receiver operating characteristic (AUROC) curve. RESULTS: The cohort comprised 65% men with a median age of 57 years (IQR 44.0-64.8). MV replacement was performed in 51.1% of patients who were older than those undergoing repair (median age 62 vs 51 years). In-hospital mortality was 4.5% and long-term all-cause mortality was 14.8%. No in-hospital deaths occurred in the repair group. In age-adjusted and sex-adjusted analyses among replacement patients, increasing age (OR 1.1; 95% CI 1.0 to 1.1; p=0.03) and diabetes mellitus (OR 7.8; 95% CI 1.3 to 48.8; p=0.02) independently predicted long-term mortality. The model demonstrated good discrimination (AUROC 0.83; 95% CI 0.69 to 0.97). Mean survival was significantly longer following repair than replacement (161.0 vs 129.9 months; p=0.008). CONCLUSIONS: MV repair for infective endocarditis is safe and associated with superior long-term survival compared with replacement. Diabetes mellitus is a strong independent predictor of mortality in the MV replacement group, highlighting the importance of risk stratification in surgical decision-making.