Simulation of cardiac action potential propagation using hybrid models

This paper investigates hybrid computational models as an approach to efficient simulation of electrical activity in cardiac tissue. In the hybrid approach, computational requirements are reduced by modelling only a local region using a detailed model, and embedding this within a simpler model of a larger tissue. We argue that the validity of this approach is dependent upon the method used to couple the different component models. We develop a simple coupling method for creating hybrid models in which the ionic Luo-Rudy phase 1 model is embedded within a tissue that uses the 3-variable Fenton-Karma model. The hybrid models are shown to preserve depolarisation fronts propagating through tissue as well as accurate action potential behaviour within embedded regions.