Contemporary 1-Year Outcomes of Mitral Valve-in-Ring With Balloon-Expandable Aortic Transcatheter Valves in the U.S.

Background Adequate valve performance after surgical mitral valve repair with an annuloplasty ring is not always sustained over time. The risk of repeat mitral valve surgery may be high in these patients. Transcatheter mitral valve-in-ring (MViR) is emerging as an alternative for high-risk patients. Objectives The authors sought to assess contemporary outcomes of MViR using third-generation balloon-expandable aortic transcatheter heart valves. Methods Patients who underwent MViR and were enrolled in the STDS/ACC TVT (Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy) Registry between August 2015 and December 2022 were analyzed. Results A total of 820 patients underwent MViR at 236 sites, mean age was 72.2 ± 10.4 years, 50.9% were female, mean STS score was 8.2% ± 6.9%, and most (78%) were in NYHA functional class III to IV. Mean left ventricular ejection fraction was 47.8% ± 14.2%, mean mitral gradient was 8.9 ± 7.0 mm Hg, and 75.5% had ≥ moderate mitral regurgitation. Access was transseptal in 93.9% with 88% technical success. All-cause mortality at 30 days was 8.3%, and at 1 year, 22.4%, with a reintervention rate of 9.1%. At 1-year follow-up, 75.6% were NYHA functional class I to II, Kansas City Cardiomyopathy Questionnaire score increased by 25.9 ± 29.1 points, mean mitral valve gradient was 8.4 ± 3.4 mm Hg, and 91.7% had ≤ mild mitral regurgitation. Conclusions MViR with third-generation balloon-expandable aortic transcatheter heart valves is associated with a significant reduction in mitral regurgitation and improvement in symptoms at 1 year, but with elevated valvular gradients and a high reintervention rate. MViR is a reasonable alternative for high-risk patients unable undergo surgery who have appropriate anatomy for the procedure. (STS/ACC TVT Registry Mitral Module [TMVR]; NCT02245763)