Determination of implanted electrode potential distributions in a man model

The finite-element (FE) method has been used to analyze and determine the potential distribution produced by implanted stimulating electrodes used in conjunction with an implanted defibrillator. These electrodes are used to deliver an energy shock to halt ventricular fibrillation during fatal arrhythmias in human beings. The FE solution was obtained by solving the Laplace equation on the basis of a Galerkin procedure. A detailed section through the thorax based on the actual geometry of a human model, including varying layers of tissue characteristics, was used to show the results of the FE model. Electrode locations were changed and the various potential distributions were obtained. The overall objective of this study was to develop a computer model for the study of defibrillation fields. This model can be used to estimate the potential distribution and potential gradients on the heart for various electrode sizes and configurations for a given shock strength