Mechanical properties of explanted porcine bioprosthetic heart valves

Bioprosthetic heart valves used to replace both the mitral and aortic valves in humans have a life span of 10-15 years. We performed uniaxial tensile tests on explanted failed porcine bioprostheses that came from both the mitral and aortic position and freshly fixed porcine aortic valves (PAV). The results showed that the explants had significantly different mechanical properties from the freshly fixed PAV. Comparison of explants from the mitral and aortic positions revealed no differences. The changes measured in the bioprostheses indicate that they have lost some of their elasticity as well as their ultimate strength