Aims: The study sought to assess outcomes of transcatheter mitral valve-in-valve implantation (TMVIV) for degenerated bioprostheses and transcatheter mitral valve-in-ring implantation (TMVIR) for failed annuloplasty rings according to access route and the Mitral Valve Academic Research Consortium (MVARC) criteria.
Methods and results: Twenty-four patients (72±13 years; eight men [33%]) underwent TMVIV (n=14) or TMVIR (n=10) for mitral regurgitation (MR; n=17) or stenosis (n=7) using balloon-expandable bioprostheses. Transapical (TA) access was chosen in 13, and transseptal (TS) access in 11 patients. MVARC technical success, device success and procedural success were 95.8%, 41.7% and 33.3%, respectively, with no differences between access routes. Cardiac output (CO) increased significantly by 1.1±0.8 l/min in TS patients, but not in TA patients (ΔCO=0.0±0.5 l/min; p=0.0051). Overall three-year survival was estimated at 57.6% (95% confidence interval: 33.9-81.3; TA 35.5% [5.2-65.9]; TS 90.9% [73.9-100]). Survival up to four years according to vascular access showed a clear benefit in patients treated transseptally (p=0.045).
Conclusions: Regardless of the access route, TMVIV/TMVIR was associated with high technical success yet impaired device success. In the long term, TA access had a significant adverse impact on survival.