Biomechanical Simulation of Transcatheter Aortic Valve Implantation

Objective:

We investigate the biomechanical mechanisms behind Transcatheter Aortic Valve Implantation (TAVI) to reduce the risk assiciated with the intervention.

Transcatheter Aortic Valve Implantation (TAVI) has been established as the new standard treatment for high-risk patients with severe aortic valve stenosis. Thereby, a replacement valve consisting of three soft tissue leaflets fixed inside a metallic, foldable support frame (stent), is positioned and unfolded inside the diseased aortic valve under beating heart conditions. The native valve leaflets are dislocated by the unfolding stent and pressed against the vascular wall. The method is being applied worldwide, efficacy and safety have been proven superior to standard treatment of inoperable patients and at least non-inferior in patients with increased operative risk. Nevertheless, the technique is linked to a number of complications. Some are rather rare, but lethal, such as ruptures of vascular of ventricular tissue or the partial or complete obstruction of the coronary arteries by the native leaflets or by a misplaced stent. More frequent, postoperative arrhythmia or bradycardia as well as paravalvular leaks along the perimeter of the stented valve are witnessed. While not directly life-threatening, these complications will require additional correction (e.g. pacemaker) and are known to result in a worse long-term perspective. Our interdisciplinary research group at University Hospital Zürich and ETH Zürich is set out to investigate the biomechanical mechanisms behind these complications with the long-term aim to derive strategies for a patient-specific optimization of the planning as well as the conduction of TAVI.

Participants: Prof. Dr. Sven Hirsch, Prof. Gábor Székely, Christoph Russ, Dr. Michael Gessat

Partners:

University Hospital Zurich - Division of Cardiovascular Surgery (Prof. Falk)

Institute of Mechanical Systems, ETH (Profs. Kuhl & Mazza)