Transcatheter Mitral Valve-in-Valve Implantation versus Conventional Redo Mitral Valve Surgery

Objectives: Transcatheter mitral valve-in-valve implantation (mViV) in patients with failing bioprostheses is an emerging alternative for high-risk patients. Our aim was to compare the early outcome of patients receiving either conventional mitral valve reoperation (Redo-MVR) or mViV for degenerated mitral valve bioprostheses.

Methods: Between 01/2001–06/2017 109 consecutive patients received Redo-MVR at our center. Of these patients 9 received conventional single Redo-MVR and were included in the study. The remaining 100 patients were excluded due to combined mitral reoperation, endocarditis or mechanical mitral valves. From 2010 until present 25 patients with a high surgical risk profile were treated with mViV. Preoperative, intra- and postprocedural data were prospectively collected in a dedicated database and analyzed retrospectively.

Results: Mean patient age (Redo-MVR 68.6 ± 18.7 years and mViV 68.2 ± 14.7 years, p = 0.89) and logistic EuroSCORE for both groups was similar (Redo-MVR 24.2 ± 13.2% versus mViV 19.7 ± 11.7%; p = 0.62).The mean procedure time was significantly longer for Redo-MVR 266.1 ± 67.8 compared with 125.3 ± 84.2 minutes for mViV (p =< 0.001). Mean time on the intensive care unit (Redo-MVR 91.3 ± 82.9h versus mViV 102.4 ± 162.5h; p = 0.87) showed no significant difference. The intubation time for Redo-MVR was longer with 28.2 ± 30.8h compared with 9.5 ± 6.8h in mViV, but did not reach statistical significance (p = 0.13),although 17 (68%) of the 25 mViV patients left the OR extubated. Mean postoperative pressure gradient after mViV and Redo-MVR showed similar results: 6.0 ± 2mmHg for mViV and 6.2 ± 1.3mmHg for Redo-MVR (p = 0.86).Patients receiving Redo-MVR showed no mitral insufficiency postoperatively while 6 (24%) patients after mViV showed mild mitral insufficiency (paravalvular n = 3). One patient with mViV received a conventional mitral valve replacement after migration of the valve. Redo-MVR had a higher incidence (n = 3) for bleeding (p = < 0.001) and postoperative pacemaker implantation (n = 1; p = 0.02). 30-day survival was 100% in both groups and 1-year survival was 100% for Redo-MVR and 90.9% for mViV (p = 0.24).

Conclusion: Transcatheter mViV can be performed safely in patients with a high surgical risk profile. Mean pressure gradients are comparable to patients after Redo-MVR. Mild regurgitation occurred only after mViV while Redo-MVR showed a higher incidence of postoperative complications. The less invasive procedure justifies mViV in selected patients to reduce complexity.