Investigation of the Fatigue Properties of Mitral Valve Leaflets

Annulus dilation is one of the main causes of functional mitral regurgitation. Although the annulus dilation is usually accompanied by left ventricle dilation and dysfunction, the mechanical relation between them is not fully elucidated yet. In this paper, the assumption is made that the ventricular dysfunction increases the cyclic loading conditions on the mitral valve apparatus. This effect may cause fatigue and weaken the tissue. This hypothesis is investigated in vitro by applying increased cyclic loadings to the tissue and evaluating the tissue stiffness during the cycles. The results of this study show that the tissue loses its strength after cyclic fatigue loadings.