Mechanical, Structural, and Chemical Analysis of Athrombogenic Multilayer Wall of Ventricular Assist Device Tested in Hydrodynamic Fatigue Tests

The purpose of the paper is to assess an impact of short- and long-term operational load on continuity and composition of TiN/Au layers deposited on the polymer Bionate II that the pulsatile ventricular assist device Religa Heart Ext is made of. The additional objective is to determine mechanical properties of the TiN/Au layers deposited on the polymer. The physical model of circulatory system was built using the Windkessel model. The tests with the use of energy dispersive spectroscopy and scanning electron microscopy were made on surfaces of samples made of the Religa Heart Ext material examined in the fatigue tests. Mechanical properties of the TiN/Au coatings deposited on the polymer were measured in the nanoindentation test by comparison of the coated and the uncoated samples.