Predictive value of the clinical frailty scale and the essential frailty toolset versus euroscore ii for 30-day outcomes after mitral valve surgery

Background: Frailty reflects reduced physiological reserve and may add prognostic information beyond conventional surgical risk scores. We compared the 30-day predictive performance of the Clinical Frailty Scale (CFS) and the Essential Frailty Toolset (EFT) with EuroSCORE II in patients undergoing mitral valve surgery. Methods: Prospective cohort of 184 patients undergoing mitral valve repair or replacement at the Vietnam National Heart Institute, Bach Mai Hospital (September 2025 to July 2026). The primary endpoint was a 30-day composite of death, major cardiovascular complications, prolonged ventilation or reintubation, prolonged vasopressor dependence, and rehospitalization for heart failure. Discrimination was compared using DeLong's test. Results: Mean age was 56.7 ± 9.8 years and 64.1% were women. Frailty was identified in 55.4% by CFS and 8.7% by EFT; only 16 of 102 patients frail by CFS were concordantly classified by EFT. The composite endpoint occurred in 107 patients (58.2%), with no deaths. Event rates rose across the three strata of all tools (p for trend < 0.001). The area under the curve was 0.809 (95% CI 0.750–0.868) for CFS, higher than EFT (0.736; p = 0.031) and EuroSCORE II (0.649; p < 0.001). Conclusions: In a relatively young mitral valve population largely classified as low risk by EuroSCORE II, frailty assessment by CFS or EFT predicted 30-day outcomes better than EuroSCORE II; CFS showed the highest discriminative ability.