AbstractBackgroundRisk stratification for transcatheter procedures in patients with severe mitral regurgitation is challenging. Deceleration capacity (DC) has already proven to be a reliable risk predictor in patients undergoing transcatheter aortic valve implantation. We hypothesized, that DC provides prognostic value in patients undergoing transcatheter edge‐to‐edge mitral valve repair (TEER).MethodsWe retrospectively analyzed electrocardiogram signals from 106 patients undergoing TEER at the University Hospital of Tübingen. All patients received continuous heart‐rate monitoring to assess DC following the procedure. One‐year all‐cause mortality was defined as the primary end point.ResultsSixteen patients (15.1%) died within 1 year. The DC in nonsurvivors was significantly reduced compared to survivors (5.1 ± 3.0 vs. 3.0 ± 1.6 ms,p= 0.002). A higher EuroSCORE II and impaired left ventricular function were furthermore associated with poor outcome. In Cox regression analyses, a DC < 4.5 ms was found a strong predictor of 1‐year mortality (hazard ratio: 0.10, 95% confidence interval: 0.13–0.79,p= 0.029). Finally, a significant negative correlation was found between DC and residual mitral regurgitation after TEER (r= −0.41,p< 0.001).ConclusionIn patients with severe mitral regurgitation undergoing TEER, DC may serve as a new predictor of follow‐up mortality.