Reappraisal of the Regurgitation Severity vs Left Ventricular Dilation Conceptual Framework for the Management of Secondary Mitral Regurgitation

Secondary mitral regurgitation (SMR) is a common and challenging cardiovascular disease. Transcatheter edge-to-edge repair (TEER) has emerged as an alternative to surgical mitral valve (MV) repair or replacement for the treatment of SMR. Although TEER has received approval from health regulating services in numerous countries, controversies remain on which subtypes of patients benefit from the intervention and whom may not. The concept of MR proportionality related to LV dilation has been introduced as a potential explanation, but given the confusion and doubts observed in clinical practice, we feel it needs to be revisited from both mechanistic and clinical standpoints.