Realistic Vascular Replicator for TAVR Procedures
Transcatheter aortic valve replacement (TAVR) is an over-the-wire procedure for treatment of severe aortic stenosis (AS). TAVR valves are conventionally tested using simplified left heart simulators (LHS). While those provide baseline performance reliably, their aortic root geometries are far from the anatomical in situ configuration, often overestimating the valves’ performance. We report on a novel benchtop patient-specific arterial replicator designed for testing TAVR and training interventional cardiologists in the procedure. The Replicator is an accurate model of the human upper body vasculature for training physicians in percutaneous interventions. It comprises of fully-automated Windkessel mechanism to recreate physiological flow conditions. Calcified aortic valve models were fabricated and incorporated into the Replicator, then tested for performing TAVR procedure by an experienced cardiologist using the Inovare valve. EOA, pressures, and angiograms were monitored pre- and post-TAVR. A St. Jude mechanical valve was tested as a reference that is less affected by the AS anatomy. Results in the Replicator of both valves were compared to the performance in a commercial ISO-compliant LHS. The AS anatomy in the Replicator resulted in a significant decrease of the TAVR valve performance relative to the simplified LHS, with EOA and transvalvular pressures comparable to clinical data. Minor change was seen in the mechanical valve performance. The Replicator showed to be an effective platform for TAVR testing. Unlike a simplified geometric anatomy LHS, it conservatively provides clinically-relevant outcomes and complement it. The Replicator can be most valuable for testing new valves under challenging patient anatomies, physicians training, and procedural planning.
KeywordsTAVI Aortic stenosis Aortic valve Mitral valve Prosthetic valve 3D printing
Calcific aortic valve disease
Effective orifice area
Left heart simulator
Transcatheter aortic valve replacement
The authors would like to acknowledge Braile Biomédica from Brazil, for providing us with the 24 mm Inovare TAVR valve.
This project was supported by NIH-NIBIB Quantum Award Phase II-1U01EB012487 (DB) and NHLBI STTR R41-HL134418 (DB).
Conflict of interest
Author OR was a consultant for Vascular Simulations LLC. Author BK is partly employed by Vascular Simulations LLC. Author CS has stock ownership in Vascular Simulations LLC. Author BL has stock ownership in Vascular Simulations LLC. Author LG declares that he has no conflicts of interest. Author DB declares that he has no conflicts of interest.
All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Informed consent was waived by the Stony Brook University Institutional Review Board as this study was retrospective and the CT scans for this study were received anonymized. This article does not contain any studies with animals performed by any of the authors.
Online Video1 Guidance of the delivery system via femoral access in the Replicator. Supplementary material 1 (MP4 20537 kb)
Online Video2 Deployment of the 24 mm Inovare valve in the Replicator. Supplementary material 2 (MP4 17906 kb)
Online Video3 Inovare valve in the Replicator post-procedural. Supplementary material 3 (MP4 13954 kb)
Online Video4 Angiogram of the severe calcified aortic valve model (S-CAVD-50) pre-TAVR. Left – original angiogram; Right – subtracted angiogram. Supplementary material 4 (MP4 2245 kb)
Online Video 5 Angiogram of the severe calcified aortic valve model (S-CAVD-50) post-TAVR. Left – original angiogram; Right – subtracted angiogram. Supplementary material 5 (MP4 2244 kb)
Online Video 6 Video of the Inovare TAVR valve; Left – in the Vivitro PD; Right – in the Replicator. Supplementary material 6 (MP4 6138 kb)
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