Aims:Transcatheter valve embolization and migration (TVEM) is a potential complication of transcatheter aortic valve implantation (TAVI) (1). Registries suggest low incidence but clinical relevance due to increased acute and mid-term mortality with the majority embolizing in the aorta (2). However, there is little data on potential late complications such as leaflet and stent thrombosis or aortic wall alterations by migrated valves. Therefore, the aim of our study was to analyze the incidence of TVEM in a large single center cohort of TAVI patients and to examine dislocated valves by ECG-gated computed tomography (CT).

Methods and Results: Between July 2009 and May 2020, 35 TVEM occurred in 2321 TAVI procedures performed at the Cardiovascular Care Unit, Charité - University Medicine Berlin (1.51%). TVEM was defined according to Valve Academic Research Consortium-2 (VARC-2) criteria (3). Annual incidence increased after initiation of our TAVI program to a maximum incidence of 3.4% in 2013 and steadily decreased from then on (lowest: 0.6% in 2018). Majority of TVEM were left in the ascending aorta (31 ascending, 3 arch, 1 descending aorta). 90.3% of TVEM occurred with a self-expanding valve (SEV), with no difference between older and newer valve generations, 9.7% with a balloon-expanding valve. No significance in correlation between the occurrence of TVEM and intrahospital mortality was shown by Fisher-Yates Test (6.5% in TVEM group vs 4.7% in total TAVI group; p=0.37). Analyzing a TAVI sample cohort (n=80), horizontal aorta, defined as aortic angulation >48°(4), was identified as predisposing risk factor (p=0.01, Odds ratio (OR) 5.2, 95% CI: [1.8:14.5]) for TVEM. Odds Ratio for TVEM in patients with horizontal aorta was severely increased when isolating analysis for the use of SEV (p=0.01, OR 18.7, 95% CI: [2.1:163]). Out of 35 TVEM patients, 6 patients were willing to participate in our imaging sub-study. CT exams were performed on average 47 months after TAVI (25%Q:16.8, 75%Q:72.8). CT identified no relevant pathological findings. In particular, we detected no leaflet or stent thrombosis or aortic wall alterations. 4 of the 6 patients were on oral anticoagulation.

Conclusions: TVEM is a rare complication of TAVI. Incidence of TVEM showed a temporal connection to the introduction dates of new first-generation valves and decreased over time with growing experience. The use of SEV and the finding of a horizontal aorta showed an increased risk for TVEM. ECG-gated CT did not detect relevant pathological findings in patients with dislocated valves left in the aorta. 

Key words: transcatheter aortic valve implantation, complications, valve embolization, valve migration, valve dislocation

1.         Ussia GP, Barbanti M, Sarkar K, Aruta P, Scarabelli M, Cammalleri V, et al. Transcatheter aortic bioprosthesis dislocation: technical aspects and midterm follow-up. EuroIntervention. 2012;7(11):1285-92.

2.         Kim WK, Schafer U, Tchetche D, Nef H, Arnold M, Avanzas P, et al. Incidence and outcome of peri-procedural transcatheter heart valve embolization and migration: the TRAVEL registry (TranscatheteR HeArt Valve EmboLization and Migration). Eur Heart J. 2019;40(38):3156-65.

3.         Kappetein AP, Head SJ, Genereux P, Piazza N, van Mieghem NM, Blackstone EH, et al. Updated standardized endpoint definitions for transcatheter aortic valve implantation: the Valve Academic Research Consortium-2 consensus document. J Am Coll Cardiol. 2012;60(15):1438-54.