Structural simulation of human mitral valve behaviour cosidering effects of material nonlinearities

Abstract

Simulation of human heart mitral valves is a challenging biomechanical problem due to its complex anatomical structure, material properties and time dependent loading conditions. This study presents a modeling and simulation of human mitral valve behavior considering the effects of material nonlinearity and Chordae tendineae rupture via a numerical analysis. Three-dimensional sized geometrical model obtained from anatomically measurement used as structural model The transient finite element method including inertia effects and time dependencies implemented for numerical solution. Two different material models have been considered to illustrate the effect of material nonlinearity on the stress and strain imposed by leaflets. On the other hand Chordae tendineae rupture caused by bacterial endocarditis, rheumatic valvular disease or trauma can be a deadly defect leads to malfunction of human heart. Chordae tendineae rupture has been also simulated to investigate the effects on leaflet stresses and strains. Based on the results, although the linear elastic model exhibits an acceptable correlation in the location of high stress regions with the hyperelastic model but Stress magnitudes differ between the elastic and hyper elastic model Depending on the strain energy function used to describe the nonlinear material, different stress magnitudes release from the analyses. Chordae rupture causes an unintended increase in the magnitude of leaflet stresses and the closed valve configuration. The increment value depends on the location and number of ruptured chordae.