Predicting endocardial potentials from epicardial potentials for external stimuli

A model is presented for calculating the potential field in the heart for externally applied current knowing only the epicardial potential distribution. To test the model, a comparison is made between potentials predicted by the model and those measured in dogs. The measured potentials were acquired in three dogs using left and right ventricular plunge electrodes and atrial wire electrodes during pacing from the body surface. The predicted potentials were generated using the measured epicardial potentials and the heart geometry in a boundary integral formulation treating the heart as a homogeneous isotropic volume conductor. A comparison between the measured and predicted potentials for three different stimulus electrode combinations produced a mean correlation coefficient of 0.986, and a mean RMS error of 20.4%.<>