Determinants of long-term clinical outcomes following transcatheter edge-to-edge repair for primary mitral regurgitation
F Lemos De Sousa, F Nunes, M L Moura, I Rodrigues, A Goncalves, A Lobo, M Almeida, D Ferreira, G Pires De Morais, B Melica, R Fontes CarvalhoAbstract
Background
Transcatheter edge-to-edge repair (TEER) is an established therapeutic option for symptomatic primary mitral regurgitation (PMR) in patients deemed at high surgical risk. Despite procedural success, long-term clinical outcomes vary considerably, and reliable predictors of mortality or heart failure (HF) hospitalization after TEER remain incompletely defined.
Methods
We performed a retrospective single-centre cohort study including consecutive patients with PMR who underwent TEER between 2015 and 2025. The primary endpoint was a composite of all-cause mortality or HF hospitalization. Time-to-event analyses were conducted using Cox proportional hazards regression. Variables considered clinically relevant and/or associated with outcomes in univariable analysis (p<0.10) were entered into multivariable models. Hazard ratios (HRs) with 95% confidence intervals (CI) were calculated.
Results
The cohort comprised 67 patients, with a mean age of 78±8 years; 39 (58%) were men and 41 (61%) had atrial fibrillation (AF). Moderate-or-greater tricuspid regurgitation (TR) was present in 46 patients (69%). During follow-up, 33 patients (49.3%) experienced the primary composite endpoint. In univariable Cox analysis, baseline left atrial (LA) volume (HR 1.006 per mL; 95% CI 1.002–1.010; p=0.008) and moderate-or-greater TR (HR 2.45; 95% CI 1.01–5.98; p=0.048) were associated with the endpoint, while AF demonstrated a non-significant trend toward increased risk (HR 2.19; p=0.057). In multivariable analysis, baseline LA volume remained the only independent predictor of adverse outcomes (HR 1.005 per mL; 95% CI 1.000–1.010; p=0.032), whereas TR (HR 1.26; p=0.675) and AF (HR 1.37; p=0.537) were not independently associated.
Conclusion
In this 10-year single-centre TEER experience, larger baseline left atrial volume was the sole independent predictor of long-term adverse outcomes, defined as death or HF hospitalization. These findings suggest that left atrial enlargement may provide relevant prognostic information after TEER for PMR, although confirmation in larger and adequately powered cohorts is warranted.