A consistent model for cardiac deformation estimation under abnormal ventricular muscle conditions

Abstract

Deformation modeling of cardiac muscle is an important issue in the field of cardiac analysis. For this reason, many approaches have been developed to best estimate the cardiac muscle deformation, and to obtain a practical model to use in diagnostic procedures. But there are some conditions, like in case of myocardial infarction, in which the regular modeling approaches are not useful. In this section, using a point-wise approach in deformation estimation, we try to estimate the deformation under some abnormal conditions of cardiac muscle. First, the endocardial and epicardial contour points are ordered with respect to the center of gravity of endocardial contour and boundary point displacement vectors are extracted. Then to solve the governing equation of deformation, which is an elliptic equation, we apply boundary conditions in accordance with the computed displacement vectors and then the Finite Element method (FEM) will be used to solve the governing equation. Using obtained displacement field through the cardiac muscle, strain map is extracted to show the mechanical behavior of cardiac muscle. To validate the proposed algorithm in case of infracted muscle, a non-homogeneous ring is modeled using ANSYS under a uniform time varying internal pressure, which is the case in real cardiac muscle deformation and then the proposed algorithm implemented in MATLAB and the results for such problem are extracted.