Transcatheter aortic valve-in-valve implantation in failed stentless bioprostheses.

<bold>Objective: </bold>To compare the safety and efficacy of transcathether aortic valve-in-valve implantation (ViV-TAVI) in degenerated stentless bioprostheses with failed stented valves and degenerated native aortic valves.<bold>Introduction: </bold>Little is known about ViV-TAVI in degenerated stentless valves.<bold>Methods: </bold>Out of 45 ViV-TAVI procedures reported in the POL-TAVI registry, 20 failed stentless valves were compared with 25 stented prostheses and propensity-matched with 45 native TAVI cases. The mean follow-up was 633 (95% confidence interval [CI], 471-795) days and Valve Academic Research Consortium-2 (VARC-2) definitions were applied.<bold>Results: </bold>Patients with degenerated stentless valves were younger (65.6, CI 58-73.1 years vs 75.6, CI 72.2-78 [stented] vs 80.1, CI 78.7-81.6 y. [native], P < 0.001). Implantation was required later after surgery (11.5, CI 8-14.9 years) in the stentless cohort as compared with the stented one (6.2, CI 4.7-7.6 years, P = 0.006). ViV-TAVI in the stentless group was also associated with larger amount of contrast (211, CI 157-266 mL vs 135, CI 104-167 mL [stented] vs 132 (119-145) mL [native], P = 0.022). Using VARC-2 composite endpoints, ViV-TAVI in stentless prostheses was characterized by a lower device success (50% vs 76% in stented vs 88.9% in native TAVI, P < 0.001), but comparable early safety up to 30 days (73.7% vs 84% vs 81.8%, respectively, log-rank P = 0.667) and long-term clinical efficacy beyond 30 days (72.2% vs 72% vs 73.8%, respectively, log-rank P = 0.963).<bold>Conclusions: </bold>Despite technical challenges and a lower device success, ViV-TAVI in stentless aortic bioprostheses achieves similar safety, efficacy, and functional improvement as in stented or degenerated native valves. [ABSTRACT FROM AUTHOR]