Simulation of myocardial growth: Investigating the effect of using idealized and realistic ventricular geometries

Abstract

Cardiac computational modeling is an approach to evaluate the behavior of this organ under different conditions. In this study, three ventricular geometries are used to investigate the effect of different cardiac geometries on myocardial growth. Furthermore, the effect of various left ventricular wall thicknesses and chamber volumes on myocardial growth have been investigated. An idealized geometry is used for the first model. In the second model, realistic human geometry was extracted from CT-scan images of the heart. In the third model, the growth formulation is implemented on a realistic geometry obtained from CT-scan data, which is adopted from a previous study. To assess the difference caused by geometries, isotropic growth and the Neo-Hookean material model was utilized. Furthermore, clinical ventricular pressures were extracted from two patients aged 42- and 45-years using the catheterization method, and the growth of each model was evaluated under two different pressures to investigate the effect of different ventricular pressures. Results show that each of the idealized and realistic geometries makes a significant difference in the distribution and magnitude of myocardial growth. Under the applied pressures, a maximum growth of 7% was observed in the basal region of the idealized geometry, and in realistic models, the amount of myocardial growth in that region was 3%. Moreover, in the idealized model, the right ventricular chamber experienced a volume increase of 9.16 ml during growth. In contrast, the increase in the right ventricular volume of the realistic models was negligible. Additionally, results illustrated that increasing wall thickness and chamber volume in idealized geometry will result in lower and higher myocardial growth, respectively. The results of this study demonstrate the importance of using realistic geometries and highlight the difference between idealized and realistic geometries in simulations of myocardial growth.