Paradox of disproportionate atrial functional mitral regurgitation and survival after transcatheter edge-to-edge repair.

This analysis introduces the MR proportionality concept in aFMR patients and its potential prognostic value. Paradoxically, disproportionate MR in aFMR was linked to a 1.35-fold increase in 2-year mortality post-M-TEER, emphasizing the importance of accurate preprocedural FMR characterization. Our findings in patients with disproportionate MR indicate that a high degree of aFMR with high regurgitant volumes may lead to aggravated symptoms, which is a known contributor to increased mortality following M-TEER. These results underline the need for further research into the pathophysiology of aFMR to inform potential preventative and therapeutic strategies, ensuring optimal patient outcomes.