Secondary retensioning of a tether-based device for transapical transcatheter mitral valve implantation

OBJECTIVES: Relevant paravalvular leakage (PVL) due to prosthesis dislodgement is a rare but potentially severe complication after transcatheter mitral valve implantation (TMVI). Due to the epicardial anchoring mechanism of the Tendyne® TMVI system, repositioning of the valve stent may be possible by retensioning of the tether. This multicentre study aimed to investigate the procedural and short-term safety as well as efficacy of retensioning manoeuvres. METHODS: From 2017 to 2021, N = 18 patients who underwent secondary tether retensioning were identified. Baseline, procedural and follow-up data were available from N = 11 patients and analysed according to the Mitral Valve Research Consortium definitions. Continuous variables are shown as median with interquartile range. RESULTS: All patients [age 75 years (73.5, 85.0), 64% male (N = 7), EuroSCORE II 6.2% (5.8, 11.6)] presented with post-procedural PVL [63.6% (N = 7) with PVL ≥3+]. Of these, 54% (N = 6) showed signs of haemolysis. The majority were severely symptomatic [New York Heart Association ≥III (91%, N = 10)]. Procedural outcomes revealed no acute complications and no mortality. At discharge, PVL was completely eliminated in 91% (N = 10) of patients with 1 case of remaining moderate PVL. At 30 days, Mitral Valve Research Consortium device success was achieved in 82% (N = 9) of patients. Two patients required open surgical mitral valve replacement due to persistent and recurrent PVL. In 89% (N = 8) of patients with successful retensioning procedure, New York Heart Association class was I/II. There was no 30-day mortality. CONCLUSIONS: This multicentre study demonstrates technical feasibility, procedural safety and acute efficacy of retensioning procedures in the majority of patients. The potential to retension the tether in transapical TMVI may provide additional management advantages in populations at high surgical risk.