Electromechanical modeling of the left ventricle: considering hyperelastic and viscoelastic properties.

Abstract

Cardiovascular disease is the leading cause of mortality worldwide, and its treatment is crucial both medically and financially. The mechanical characteristics of the myocardium, known to be nonlinear, anisotropic, and viscoelastic, plays an essential role in the response of the heart to loading and unloading in each cardiac cycle. In this study, a simple electromechanical model that provide readily implementation was developed. A three-element Windkessel model was utilized to simulate ventricular pressure in COMSOL Multiphysics. The effect of transversely isotropic hyperelastic and Kelvin–Voigt viscoelastic models on the left ventricular function was investigated. The viscoelastic model significantly affected myocardial rate of deformation. Therefore, in heart diseases where the interactivities of frequencies is considerably higher, the viscoelastic model is expected to have a greater effect on myocardial response. Furthermore, the viscoelastic model compared to the hyperelastic case was slightly more consistent with the experimental observations, indicating the importance of including myocardial viscoelasticity. However, in order to demonstrate the efficiency of the viscoelastic model, results should be compared with a range of detailed experimental data in the future. Nonetheless, the electromechanical model presented in this study was able to recreate the overall function of the left ventricle. The model demonstrated the effect of viscoelasticity on cardiac cycle and provides a straightforward implementation and high reproducibility for other researchers. In future, the model can be expanded to investigate the effect of viscoelasticity on various heart diseases.