Examining some difficulties faced in retrieving cardiac electrical conductivities from potential measurements

Electrophysiological simulations of cardiac tissue can facilitate an understanding of the heart that often cannot be achieved through experimental means alone. However, these simulations rely on parameters that are yet to be determined with certainty; most notable are the set of six cardiac bidomain conductivities that characterise the conduction in the three orthogonal directions of the heart. This talk presents techniques used to retrieve these conductivities and, using polynomial chaos based sensitivity techniques, attempts to understand some of the difficulties associated with retrieving the conductivities from measurements of potential. Specifically, we perform a sensitivity analysis to examine higher-order interactions between the six cardiac conductivities during the retrieval procedure and try to understand the effects of these interactions on the accuracy of the retrieved conductivity. We then use these results to make suggestions for future work to improve the conductivity retrieval technique.