Transcatheter Mitral Edge-to-Edge Repair: A Selection of the Mitral Regurgitation Subtype and Definition of the Optimal Time for Intervention

In the era of mitral transcatheter edge-to-edge repair (M-TEER), growing evidence continues to support a shift from a binary classification of mitral regurgitation (MR) into primary and secondary forms toward a more refined, subtype-based approach. Additionally, anatomical and pathophysiological heterogeneity significantly influences procedural complexity, durability of repair, and clinical outcomes within both primary and secondary MR. Furthermore, recent trials suggest that the timing of the intervention is as critical as patient anatomy; delaying treatment until advanced ventricular remodeling has occurred may limit the benefits of MR reduction. Moreover, long-term data on durability and device-failure management remain limited, particularly in secondary MR, where the progression of the underlying cardiomyopathy largely determines the outcomes. Thus, this review underscores how integrating MR subtyping with intervention strategies may influence patient selection and highlights the need for future research to adopt a more individualized, mechanism-driven approach.