A Novel Morphological Classification to Guide Transcatheter Mitral Valve Edge-to-Edge Repair for Commissural Mitral Regurgitation

Mitral commissural prolapse poses significant anatomical challenges that can hinder the effectiveness of transcatheter edge-to-edge repair (TEER). The aim of this study was to estimate the safety and effectiveness of applying a novel morphological classification to guide TEER in patients with commissural degenerative mitral regurgitation (DMR). In this prospective, multicenter study across 18 centers in China, we classified patients with severe commissural DMR into 4 morphological types through detailed echocardiographic analysis. Customized TEER strategies were applied accordingly. Procedural success, clinical outcomes, echocardiographic parameters, and quality of life were assessed over a follow-up period, with a median follow-up of 18 months (Q1-Q3: 15-21 months). Among 540 patients screened, 126 (23.3%) exhibited commissural involvement. Tailored TEER strategies were successfully applied to 68 patients, achieving a technical success rate of 100% (n = 68 of 68; 95% CI: 0.933-1.000) and a device success rate of 97.1% (n = 66 of 68, 95% CI: 0.888-0.992). The 1-year follow-up revealed that 94.1% (n = 64 of 68; 95% CI: 0.849-0.981) of patients had residual mitral regurgitation of grade ≤2+, with 82.4% (n = 56 of 68; 95% CI: 0.708-0.902) at grade ≤1+, and no major complications. Additionally, significant improvements were noted in left ventricular dimensions and functional status. Our results highlight the value of the morphological classification system in enhancing TEER for commissural DMR. By addressing specific anatomical challenges, this system promotes tailored interventions that optimize procedural success and improve patient outcomes.