COMPUTER-SIMULATION OF EPICARDIAL POTENTIALS USING A HEART-TORSO MODEL WITH REALISTIC GEOMETRY

Previous cardiac simulation studies have focused on simulating the act ivation isochrones and subsequently the body surface potentials, Epica rdial potentials, which are important for clinical application as well as for electrocardiographic inverse problem studies, however, have us ually been neglected, This paper describes a procedure of simulating e picardial potentials using a microcomputer-based heart-torso model wit h realistic geometry, Our heart model developed earlier is composed of approximately 65000 cell units which are arranged in a cubic close-pa cked structure, An action potential waveform with variable in duration is assigned to each unit, The heart model, together with the epicardi al surface model constructed recently, are mounted in an inhomogeneous human torso model. Electric dipoles, which are proportional to the sp atial gradient of the action potential, are generated in all the cell units, These dipoles give rise to a potential distribution on the epic ardial surface, which is calculated by means of the boundary element m ethod, The simulated epicardial potential maps during a normal heart b eat and in a preexcited beat to mimic Wolff-Parkinson-White (WPW) synd rome are in close agreement with those reported in the literature.