Long-term outcomes of mitral valve surgery in infective endocarditis: a single-centre UK experience

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.