Influence of gap junction dynamics on the stability of reentrant waves in cardiac tissue

Constant conductances are often assumed when modeling cardiac tissue. However experimental evidences have shown that gap junctions (GJ) actually connect adjacent cardiac myocytes. These GJ are complex proteins of the connexin family (Cx40; Cx43; Cx45 are the most common in human). These GJ modify the conductances between cardiac cell through a dynamical process. The aim of this study is to develop a bidomain model of the cardiac tissue where the dynamics of the connexins is also included. In particular we will compare the differences associated with the use of a monodomain versus bidomain formulation in inducing intra-cellular conductance variations. We have found that the monodomain formulation gives conductance variations a factor four to five larger with respect to the bidomain formulation.