Finite Element Modeling And Biomechanical Analysis Of Mitral Valve

Mitral valve, the important tissue of the heart, is located between the left atrium and the left ventricle, it consists of two leaflets, anterior and posterior, attached to the papillary muscles in the ventricle via tendons known as chordae tendinae or chordae, regulating blood flow between the left ventricle and the left atrium. An important factor to affect the biological life of the valve is the stress distribution. The biological valves tears because of the excessive mechanical stress in clinical. It is directly related to the stress distribution of the valve leaflets. The valve leaflets torn with perforation occurred in the stress concentration region, so research on the mechanical properties of prosthetic valve is of great significance for the optimal design of the valve structure. Meanwhile, it is helpful to understand the principles of dysfunction of bioprosthetic valves.Based on physiological characteristics of the mitral valve, we use UG and ANSYS to simulate the mitral valve. Firstly, the paper introduces the related physiological knowledge of the mitral valve, the pathophysiology of mitral valve prolapse, the theoretical basis of finite element analysis and the modeling methods of the mitral valve. Secondly, the geometry model of the stentless quadrileaflet pericardial mitral valve is designed, then the model is simulated and the experimental results are discussed, then the relationship between the stress distribution and the width of the leaflet is discussed. At the same time, the model of the real mitral valve is established, and the model is simulated by using the LS-DYNA. Lastly, according to the pathological characteristics of mitral valve prolapse, we establish a pathological model and simulate the hemodynamic status of mitral valve prolapse with different level. The experimental results are matched actual physiological characteristics. The main contents and innovation of this dissertation are as follows:1. Based on the stentless quadrileaflet mitral valve and the new CS stentless quadrileaflect mitral valve, the stentless pericardial mitral valve model is established, then obtains the deformation and the stress distribution through the finite element method. The results are matched actual physiological characteristics, proving that the finite element analysis and the model are proper. Last, the relationship between the width of the leaflet and the stress distribution is discussed.2. Based on the physiological characteristics of the mitral valve, we establish a mitral valve model which is more similar to the real mitral valve. Then the mitral valve model is simulated during the Cardiac cycle. The results are well consistent with clinical experience data, which further verified the validity of the model and simulation methods. At last, the auxiliary models are established to analyze the relationship between the thickness of the leaflet and the stress distribution.3. On the basis of pathological characteristics of mitral valve prolapse, we simulate the pathological phenomena of mitral valve prolapse with different level, observe the deformation and the stress distribution changes of the mitral valve.