Abstract Objective The timing of surgical correction of mitral regurgitation remains controversial. A major source of dispute regards the potential short- and long-term postoperative outcome penalty associated with the type of guideline-based indication for surgery. Methods Between 1990 and 2000, 1512 patients (aged 64 ± 14 years, mitral prolapse in 89%, valve repair in 88%) underwent surgical correction of pure organic mitral regurgitation. Patients were stratified according to surgical indication into class I triggers (ClassI-T: heart failure symptoms, ejection fraction <60%, end-systolic diameter ≥40 mm, n = 794), class II triggers based on clinical complications (ClassII-CompT: atrial fibrillation or pulmonary hypertension, n = 195), or early class II triggers based on a combination of severe mitral regurgitation and high probability of valve repair (ClassII-EarlyT: n = 523). Results Operative mortality was highest with ClassI-T (1.1% vs 0% and 0%, P  = .016). Long-term survival was lower with ClassI-T (15-year 42% ± 2%; adjusted hazard ratio HR, 1.89; 95% confidence interval CI, 1.53-2.34; P  < .0001) and ClassII-CompT (15-year 53% ± 4%, adjusted HR, 1.39; 95% CI, 1.04-1.84; P  = .027) versus ClassII-EarlyT (15-year 70% ± 3%, P  < .0001). Postoperative excess mortality with ClassI-T and ClassII-CompT was confirmed by age stratification, inverse probability weighting, and expected survival adjustment. Excess postoperative heart failure was high with ClassI-T (adjusted HR, 2.49; 95% CI, 1.82-3.47; P  < .0001) and ClassII-CompT (adjusted HR, 1.98; 95% CI, 1.30-3.00; P  = .002). Conclusions The type of guideline-based indication for surgical correction of organic mitral regurgitation is associated with profound outcome consequences on long-term postoperative mortality and heart failure, despite low operative risk and high repair rates. Conversely, surgical correction of severe mitral regurgitation based on high probability of repair (ClassII-EarlyT) is associated with improved survival and low heart failure risk and should be the preferred strategy in valve centers offering low operative risk and high repair rates.