Impact of heart failure severity on the mortality benefit of mitral transcatheter edge-to-edge valve repair

Background: To assess the interaction between heart failure (HF) severity and optimal reduction of secondary mitral regurgitation (SMR) on mortality in patients undergoing transcatheter edge-to-edge repair (M-TEER). Methods and results: Among 1656 patients included in the Italian Society of Interventional Cardiology (GIse) registry Of Transcatheter treatment of mitral valve regurgitaTiOn (GIOTTO) 984 had SMR and complete data on advanced HF. Advanced HF was defined as NYHA class III or IV, left ventricular ejection fraction ≤ 30%, and > 1 HF hospitalization during the last 12 months. Optimal M-TEER was defined as residual SMR ≤ 1 + at discharge. One hundred sixteen patients (11.8%) had advanced HF. Achievement of an optimal SMR reduction was similar in patients with and without advanced HF (65% and 60% respectively). Advanced HF was an independent predictor of 2-year all-cause death (adjusted HR 1.52, 95% CI 1.09-2.10). Optimal M-TEER, as compared to a no-optimal M-TEER, was associated with a reduced risk of death both in patients with advanced (HR 0.55, 95% CI 0.32-0.97; p = 0.039) and no-advanced HF (HR 0.59, 95% CI 0.46-0.78; p < 0.001; p = 0.778 for interaction). Conclusions: Advanced HF is associated with poor outcome in patients undergoing M-TEER. However, an optimal SMR reduction reduces the risk of 2-year mortality regardless of HF severity.