Comparative Analysis of Central and Noncentral Degenerative Mitral Regurgitation Treated With Transcatheter Mitral Valve Edge-To-Edge Repair.

Background: Mitral valve transcatheter edge-to-edge repair (M-TEER) was initially indicated for central degenerative mitral regurgitation (DMR) lesions, but advancements in technology have enabled successful treatment in an increasing number of noncentral DMR patients.

Aims: This study aims to compare procedural outcomes and prognosis between noncentral DMR patients, outside clinical trial anatomical criteria, and central DMR patients undergoing M-TEER.

Methods: Drug-refractory moderate-to-severe DMR patients treated with M-TEER at Fuwai Hospital from January 2021 to February 2024 were retrospectively analyzed. Patients were categorized into central (N = 77) and noncentral (N = 59) lesion groups. Baseline characteristics, procedural outcomes, and prognoses were collected and compared.

Results: There were no significant differences in baseline characteristics and preoperative echocardiographic parameters between the groups except for left ventricular ejection fraction. Both groups exhibited similar procedural success rates (central: 93.51% vs. noncentral: 91.53%, p = 0.92) with comparable procedural complication rates. The ideal M-TEER success rate at discharge for noncentral DMR patients was similar to that for central DMR patients (83.05% vs. 71.43%, p = 0.11). Kaplan-Meier analysis indicated similar 3-year recurrence-free survival rates (noncentral: 94.9% vs. central: 90.3%, p = 0.46). Cox regression analysis identified higher discharge mitral valve gradient and a leaflet-to-annulus index ≤ 1.2 as independent risk factors for recurrence or death.

Conclusion: Noncentral DMR patients undergoing M-TEER achieve similar procedural success rates without increased risk of complications compared to central DMR patients. The seemingly higher success rate in noncentral DMR patients may be due to the smaller impact on valve area, warranting further investigation.