Stress and strain of multilayer model for the left ventricle

Abstract

© 2017 by Begell House, Inc. The number of heart disease cases increases every year. In order to accurately diagnosis this disease, it is necessary to understand the heart's behavior, especially the mechanical properties of the heart such as stress and strain. There are many computational models for the left ventricle (LV) representing the myocardial layer or muscular wall, but none of them include endocardium and epicardium at the inner and outer walls of the heart, respectively. Even though, these tissues are very thin, they show a highly nonlinear behavior when loaded in plane. Thus, this study includes endocardium and epicardium into the LV model of a truncated ellipse. Stress and strain of an ellipse shape are determined by modification from the cylindrical model. Nonlinear and linear fiber distributions across the myocardial wall are investigated. The work is also compared to others by varying the wall-to-cavity volume ratio and muscle fiber distribution for model verification. The result shows that circumferential and longitudinal strain distribute continuously across each layer as well as radial stress. Strain of linear and nonlinear fiber distribution correspond well with others.