The generalized myocyte-fibroblast Fitzhugh-Nagumo bioheat model: design and study

The effects of fibroblast on the excitable media are investigated using a proposed myocyte-fibroblast Fitzhugh-Nagumo bioheat model. At the cellular level, the model of human excitable cell and fibroblast is modified to incorporate the Penne bioheat equation with the addition of the Joule effect. The spatial discretization is based on the fourth-order finite difference approximation and the implicit forward Euler method for the time stepping for the study the one-dimensional (1D) model. We introduce a fine adaptive algorithm of the Comsol Multiphysics software to solve the two-dimensional (2D) model and initiate spiral waves. The effects of fibroblast are analyzed in 1D and 2D models under normal and fibrillation conditions. We establish that the fibroblast slows down wave propagation, induces conduction block, is responsible for the rapid thermal block and dissipates temperature in the medium. Our research exhibits the role played by the fibroblast in modulating the electrothermal activities of cardiac or excitable cells.