Fabrication and Evaluation of Nitinol Thin Film Heart Valves
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In recent years new innovations improved the technology of devices for transcatheter heart valve replacement. In order to fabricate an efficient, durable, less thrombogenic and very thin heart valved stent for transcatheter implantation, heart valve leaflets of Nitinol (NiTi) thin film were developed. This work presents a method to fabricate NiTi thin film leaflets for transcatheter aortic valve replacements. NiTi valve leaflets were fabricated in different film thicknesses (10, 15 and 20 µm) by magnetron sputter deposition and a subsequent forming process. Pulsatile testing was performed to investigate the transvalvular pressure differences during systole and diastole as well as the effective orifice area of the valves. Furthermore, the steady backflow leakage rate under hydrostatic pressure was evaluated. Two samples from Edwards Lifescience (SAV 19 mm, and Perimount Magna 25 mm) were taken as a reference. In this experimental study, we present first in vitro test results of the newly developed NiTi leaflets.
KeywordsHeart valves Transcatheter aortic valve implantation Prosthetic valves Shape memory alloy Nitinol
This work was supported by the German Research Foundation (QU146/11-1) (LU 663/11-1).
Conflict of Interest
Authors Klaas Loger, Alexander Engel and Martin Marczynski-Bühlow declare that they have no conflict of interest. Author Rodrigo Lima de Miranda is partner of the Acquandas GmbH (Kiel) and holds several patents on shape memory thin films techniques. Author Eckhard Quandt reports funding of the project by the German Research Foundation (DFG). He is partner of the Acquandas GmbH (Kiel) and holds several patents on shape memory thin films techniques. Author Georg Lutter reports funding of the project by the German Research Foundation (DFG).
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