Simulation of depolarization in a membrane-equations-based model of the anisotropic ventricle

The results of a simulation study of the propagation of depolarization in inhomogeneous anisotropic (monodomain) myocardial tissue are presented. Simulations are based on modified Beeler-Reuter membrane equations, and performed on a block of anisotropic myocardium with rotating fiber geometry, measuring 1 cm×1 cm×0.3 cm, at various levels of spatial discretization (0.15 mm, 0.30 mm, 0.60 mm). At a discretization level of 0.6 mm the algorithm allowed the simulation in a realistically shaped model of the ventricle, including rotational anisotropy, as well. For this simulation results are justified by comparing results for the block at various levels of discretization, for which the surface to volume ratio has been adjusted. By placing the model ventricle in a realistically shaped (human) volume conductor model, realistic body surface potentials (QRST waveforms) are simulated.