Prognostic Value of Prolapse Width for Mid-Term Degenerative Mitral Regurgitation Stability After Transcatheter Edge-to-Edge Repair.

BACKGROUND: Long-term durability of degenerative mitral regurgitation (DMR) reduction after transcatheter edge-to-edge repair (TEER) remains limited, and reliable anatomical predictors are still lacking. METHODS: This study prospectively enrolled patients with symptomatic DMR undergoing TEER across 27 centers in China. All pre-procedural clinical and echocardiographic parameters were collected and analyzed. The primary outcome was MR ≤ 1+ at 3-year follow-up. Logistic regression and receiver operating characteristic (ROC) analyses were performed to identify predictors and optimal cutoff values. RESULTS: A total of 78 patients with available 3-year echocardiographic assessments were included in the imaging-based analysis (mean age, 74.4 ± 5.1 years; 67.9% with NYHA class III/IV symptoms; mean STS score for mitral valve replacement, 6.8 ± 2.7%). At 3-year follow-up, 49 patients (62.8%) maintained MR ≤1+. TEER was associated with significant reverse cardiac remodeling, including reductions in left ventricular end-diastolic volume (125.4 ± 40.6 to 99.8 ± 19.7 mL) and pulmonary artery systolic pressure (43.0 ± 11.6 to 34.3 ± 11.4 mmHg) (both p < 0.001), while LVEF remained stable. Mitral valve (MV) prolapse/flail width independently predicted MR durability (OR: 0.789; 95% CI: 0.655-0.951; p = 0.013). ROC analysis identified a cutoff value of 16 mm (AUC: 0.714; p = 0.002), with patients having prolapse/flail width ≥16 mm demonstrating lower rates of MR ≤1+ at 3 years. CONCLUSIONS: Pre-procedural prolapse/flail width is an independent predictor of 3-year MR durability after TEER in patients with DMR. Larger prolapse/flail width is associated with reduced mid-term MR stability, suggesting its potential value for risk stratification and procedural planning. TRIAL REGISTRATION: This study has been registered at ClinicalTrials.gov with a number of NCT04734756.