Defibrillation Thresholds: A Generalised Polynomial Chaos Study

This study aims to understand the effect of variations in cardiac conductivity values on defibrillation thresholds in a simple heart-in-a-bath model. A generalised polynomial chaos approach is used to generate 41 sets of four cardiac conductivity values based on the three commonly used data sets. Simulations, using the bidomain equations, are per-formed on an isolated heart placed in a bath with a pair of defibrillation paddles, of varying potential differences, at the sides of the bath. The polynomial chaos approach allows the calculation of mean and variance of extracellu-lar potential and potential gradient fields within the heart. The results show that conductivity values have a significant effect on the thresholds required to defibrillate the heart. 1