Computational biology of propagation in excitable media models of cardiac tissue

Biophysically detailed models of the electrical activity of single cardiac cells are modular, stiff, high order, differential systems that are continually being updated by incorporating new formulations for ionic fluxes, binding and sequestration. They are validated by their representation of the ionic flux and concentration data they summarise, and by their ability to reproduce cell action potentials, their stability to perturbations, structural stability and robustness. They can be used to construct discrete or continuous, one- (1D), two- (2D) or three-dimensional (3D) virtual cardiac tissues, with heterogeneities, anisotropy and realistic cardiac geometry. These virtual cardiac tissues are being applied to understand the propagation of excitation in the heart, provide insights into the generation and nature of arrhythmias, aid the interpretation of electrical signs of arrhythmia, to develop defibrillation and antiarrhythmic strategies, and to prescreen potential antiarrhythmic agents.