Research Method of Fatigue Performance of Surgically Implanted Heart Valve Stent

The aim of this study was to evaluate the fatigue property in vitro of a domestic surgically implanted heart valve stent (SIHVS). The domestic SIHVS was used as a testing sample, and a protocol was developed according to the standards GB 12279-2008 and ISO 5840-2:2015. A dynamic fatigue testing machine was used to apply for a 0.365 mm cyclic radial displacement at the end of the SIHVS. The SIHVS were observed after 400 million cycles by a scanning electron microscope. The observed results show that the structure of SIHVS is intact. There are no fracture, no obvious wear, and no loosening of the wire and casing. In the tested stents, no structural distortion, no cracks and obvious pits were observed. This study demonstrated that SIHVS structure meets the expected fatigue performance requirements.