Conductance volumetric model of an eccentrically positioned catheter within a three-compartment ellipsoidal ventricle

A mathematical model of the electric field generated and resistance measured by a conductance catheter within a three-compartment ellipsoidal approximation of a cardiac ventricle is presented. The model is based on a combination of analytical and numerical techniques. The numerical component of the model predicts displacement of the catheter along the central longitudinal ventricular axis, as well as eccentric positions off that axis. The analytical component of the model enables interactive definition of model parameters during simulation. This combination enables validation studies that include simulations of various catheter movements within a ventricle of changing geometry to be performed. The simulation results agree with the results of previous investigators studying ex-vivo systems.