Transcatheter edge-to-edge repair in secondary mitral regurgitation.

Secondary mitral regurgitation (SMR) is frequent among patients with heart failure (HF) with reduced ejection fraction (HFrEF), and it is strongly associated with increased mortality, frequent hospitalisations, and poor quality of life. The mechanisms underlying SMR are multifactorial. While guideline-directed medical therapy and cardiac resynchronisation therapy remain the cornerstone of HFrEF management, many patients with significant SMR continue to experience significant symptoms and adverse outcomes. Managing SMR within the context of HF necessitates a multifaceted approach. Transcatheter edge-to-edge repair (TEER) has emerged as a transformative intervention, demonstrating improvements in survival, functional capacity, and HF-related hospitalisations in clinical trials and real-world registries in selected patients. This review provides a comprehensive overview of the evidence supporting TEER, focusing on procedural and follow-up outcomes, and its role in reshaping the therapeutic approach for HF patients with SMR. Additionally, we highlight the critical role of patient selection and identify predictors of poor outcomes as key determinants of TEER success.