Abstract: | This study aims to observe the durability of a pyrolytic carbon bileaflet mechanical valve prosthesis.The mechanical valves prosthesis was tested in vitro by the durability test instrument of valve prosthesis.Then in vivo,the durability of the implanted valves was observed with animal experiments and clinical application.In the impact test for 5 min and durability test of 380 million cycles in vitro,there was no the phenomenon of flyer,perforation and fracture observed,as well as no wear or pit found on the surface of valve leaflets.The valve leaflets could normally be turned on or off.The weight of the valve was(1.0031 ± 0.0004) g for 23 mm and(1.6003 ± 0.0002) g for 27 mm.The hydrodynamics test demonstrated that the valve prosthesis had still excellent hemodynamic performance after the durability test.The animal autopsy showed that the valve leaflets could normally be turned on or off,and no wear was found.By follow-up of 62 patients implanted the valves,all patients had long-terms survival,no complication caused by valve was found.The age of the longest survival was more than 10 years.This study demonstrates that the new mechanical valve prosthesis have excellent durable performance. |