Self-expanding transcatheter aortic valve implantation for degenerated Mitroflow bioprosthesis: Early outcomes.

Background: The aim of this study was to assess the safety and effectiveness of valve in valve (VIV) TAVI with the autoexpandable valve, specifically in patients with failed Mitroflow (MF) bioprosthetic aortic valves.

Methods: Pilot, single center, observational and prospective study that included 45 consecutive patients with symptomatic failed MF bioprosthetic aortic valve, referred for VIV TAVI. The safety primary endpoint was a composite of early events at 30 days, defined by VARC-2 criteria. The efficacy primary endpoint was the device success (no procedural mortality, correct positioning of a single prosthetic heart valve into the proper anatomical location and absence of moderate/severe prosthetic aortic valve regurgitation). We also analysed patient-prosthesis mismatch (PPM) parameters.

Results: Between March 2012 to December 2017, 45 symptomatic patients (age 79.9 ± 6.5 years) with degenerated MF valves (numbers 19: 33.3%; 21: 28.9%; 23: 24.4%; 25: 13.3%) underwent CoreValve (n = 11) or Evolut R (n = 34) implantation (23 and 26 mm sizes). The STS predicted risk of mortality was 6.3 ± 6.3%. The safety primary endpoint occurred in 4 patients (8.8%). The efficacy endpoint was present in all patients (100%). There were no coronary occlusions or procedural deaths. The number of patients with any degree of PPM raised from 51.1% (pre-TAVI) to 60% (post-TAVI).

Conclusions: Self-expanding TAVI for degenerated MF bioprosthesis has favourable early outcomes. The VIV procedure has provided an important gateway to avoiding high-risk redo surgery and is now a potential option for MF failed surgically aortic implanted valves.