Transactions of Famena, cilt.48, sa.2, 2024 (SCI-Expanded)
Electrocardiography is a commonly used diagnostic method based on reading electrical potentials on the human torso. Ischemia is a common pathology diagnosed with electrocardiography and also the subject of many forward and inverse simulation studies. In these studies, ischemia is usually modelled by imposing an unhealthy transmembrane potential on the diseased region without taking the associated change in electrical conductivity of the ischemic tissue into account. Our objective in this paper is to investigate numerically the effect of ischemic conductivities imposed on the ischemic region on the outcome of the forward electrocardiography problem of simulation of the ischemic heart. To achieve this objective, a finite element code was written to solve the bidomain problem on realistic thorax geometries with inhomogeneous and anisotropic conductivities. The geometric model for this study consists of a single two-dimensional slice of MRI data available from the University of Utah resources. Realistic conductivities are assigned to healthy and ischemic tissues which are refined to achieve higher spatial density in order to improve numerical solution accuracy. The results show that taking into account ischemic conductivity may significantly change the estimated torso potentials in the forward analysis. We conclude that ischemic heart tissue should be simulated not only by imposing an unhealthy transmembrane potential but also unhealthy conductivities in numerical studies to achieve a more accurate simulation of this pathology.