AN INTERACTIVE 3D ANISOTROPIC CELLULAR-AUTOMATA MODEL OF THE HEART

A 3D cellular anisotropic automata model with modifiable geometry is d escribed. The modeling parameters include grain size, fiber orientatio n, and free-wall and septal thickness. From this modifiable model, thr ee specific models corresponding to normal heart, left ventricular hyp ertrophy, and ventricular dilatation were generated. Each model is a c onduction and propagation model in which the atria, the major atrial v essel bases, the ventricles, and the specialized conduction system are represented. Muscle tissues are modeled as bundles of fibers with ani sotropic conduction speed of the activation wavefronts. Regional varia tions of conduction, refractory gradients, and regional potential grad ients can also be specified before each simulation. Each element has a daptive properties with respect to cycle length and to the prematurity of incoming impulses. Action potentials can be specified for each cel l and an equivalent source formulation is carried out to simulate the vectorcardiogram and the corresponding 12-standard-lead electrocardiog ram. (C) 1998 Academic Press.