Clinical Outcomes of First-Time and Redo Mitral Valve Replacement Using MITRIS RESILIA Bioprosthesis.

Background: The MITRIS RESILIA bioprosthetic valve incorporates anticalcification technology and is designed to facilitate implantation in fragile mitral annuli. However, clinical data on its safety and hemodynamic performance remain limited. Methods: We conducted a retrospective multicenter study of 140 patients (mean age, 75 ± 8 years; 44% male) who underwent first-time (n = 100) or redo (n = 40) mitral valve replacement (MVR) with a MITRIS RESILIA valve between 2021 and 2022. The primary indication for first-time MVR was mitral regurgitation, followed by mitral stenosis, whereas that for redo MVR was prosthetic valve dysfunction, followed by failed repair. The mean follow-up duration was 36 ± 14 months (415 patient-years). Results: The most frequently implanted valve size was 27 mm (31%), followed by 29 mm (26%) and 25 mm (24%). Thirty-day mortality was 2.0% for first-time MVR patients and 0% for redo patients. At 3 years, freedom from all-cause mortality, reoperation, stroke, and structural valve deterioration was 89%, 99%, 96%, and 100%, respectively, with no intergroup differences. The mixed effects model found stable and favorable prosthetic hemodynamics over time-reflected by mean pressure gradients, effective orifice area, and the absence of major paravalvular leakage. Both groups showed sustained reductions in left atrial size and tricuspid regurgitation pressure gradient, accompanied by parallel improvements in New York Heart Association functional class (all time effect Conclusions: First-time and redo MVR with the MITRIS RESILIA valve was associated with low perioperative mortality, favorable safety, and durable hemodynamic performance. These findings support its use across a broad spectrum of mitral valve diseases.