It has been suggested in the literature that a disorgani-sation of cardiac tissue at the cellular scale may affect the propagation of the action potential (AP) at the tissue scale, and may play a role in arrhythmia. We developed a model of the myocardium at sub-cellular resolution in which the intracellular space, the cell membrane , and the extracellular space are discretized individually [1]. We present in this article an improvement of this model, including gap junction models at any interface between cells. We then test this approach on hand-crafted two-dimensional networks of a hundred of cells, and compare it with our previous model which did not include gap junctions modelling.