Background Mitral valve transcatheter edge-to-edge repair (M-TEER) is an established treatment option for patients with severe symptomatic functional mitral regurgitation (FMR) at high or prohibitive surgical risk. Differences in FMR etiology may influence procedural and clinical outcomes after M-TEER. Atrial FMR (aFMR) has been increasingly recognized as a distinct entity, most commonly occurring in the setting of atrial fibrillation or heart failure with preserved ejection fraction. Unlike ventricular FMR, which results from left ventricular remodeling and papillary muscle displacement, aFMR is characterized by mitral annular dilation secondary to left atrial enlargement and atrial remodeling. Comparative data between the two most frequently used M-TEER devices in aFMR remain limited. Therefore, this study aimed to compare the efficacy of M-TEER using the MitraClip G4 and PASCAL systems in patients with aFMR.
Methods. This single-center study included all consecutive patients with severe symptomatic aFMR who underwent M-TEER with either MitraClip G4 or PASCAL between 2021 and 2023. Propensity score-matching was performed to account for baseline differences. The co-primary endpoints were mitral regurgitation (MR) grade post-procedure and at 1 year follow-up. Secondary outcomes included New York Heart Association (NYHA) class and all-cause mortality at 1 year.
Results. A total of 152 patients were included in this registry, of whom 77 (51.0%) underwent M-TEER with MitraClip G4 and 75 (49.0%) with PASCAL. Propensity score-matching yielded 100 matched pairs. Post-procedure, MR grade ≤2 was achieved in 95.9% of the MitraClip G4 group and 93.9% of the PASCAL group (p=0.17). Similarly, residual MR grade ≤2 at 1 year was observed in 87.5% versus 92.9% of patients (p=0.09). NYHA functional class improved from III/IV in 90.0% of MitraClip G4 patients and 86.0% of PASCAL patients to I/II in 39.2% and 48.2%, respectively (p=0.77). Survival at 1-year was 85.1% in the MitraClip G4 group and 93.8% in the PASCAL group (p=0.20).
Conclusions. Both the MitraClip G4 and PASCAL systems achieved high procedural success, durable MR reduction, and similar 1‑year clinical outcomes in patients with aFMR.
