Long-Term Outcomes After Edge-to-Edge Repair of Secondary Mitral Regurgitation: 5-Year Results From the EuroSMR Registry.

Mohammad Kassar and Stephan Windecker are members of the EuroSMR Investigators.

Background
Mitral valve transcatheter edge-to-edge repair (M-TEER) reduces secondary mitral regurgitation (MR) in heart failure and impacts survival in selected patients as demonstrated in the COAPT (Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients with Functional Mitral Regurgitation) trial. However, long-term outcome data after M-TEER under real-world conditions are lacking.
Objectives
This study sought to assess long-term efficacy and survival after M-TEER in a large real-world registry.
Methods
We analyzed patients with significant secondary MR undergoing M-TEER from the EuroSMR (European Registry of Transcatheter Repair for Secondary Mitral Regurgitation) registry. Long-term MR reduction, functional outcomes, survival rate, and predictors for all-cause mortality were assessed.Results
In this study, 1,628 patients undergoing M-TEER (mean age 73.8 years, mean EuroSCORE II [European System for Cardiac Operative Risk Evaluation II] 6.9%, 86.6% NYHA functional class ≥III) with available long-term data were included. Five-year survival was 35.0%. Long-term MR reduction (MR grade ≤2+: baseline 4.1%, discharge 92.2%, 5-year follow-up 85.5%; P < 0.001) and functional improvement (NYHA ≤II: baseline 13.4%, 5-year follow-up 60.1%; P < 0.001) was observed. The degree of residual MR was associated with 5-year survival (residual MR grade ≤1+: 38.6%; 2+: 30.5%; ≥3+: 22.6%; P < 0.001). Independent predictors for 5-year all-cause mortality post-M-TEER included age, renal function, residual MR, NYHA functional class, left ventricular ejection-fraction, and COAPT trial eligibility (P < 0.01 for all).
Conclusions
This extensive multicenter registry underscores the long-term efficacy of M-TEER in real-world clinical practice and identifies predictors for long-term survival. These findings contribute valuable insights for optimizing patient selection in routine clinical interventions.