Conductance heterogeneities induced by multistability in the dynamics of coupled cardiac gap junctions

In this paper, we study the propagation of cardiac action potential in a one-dimensional fiber, where cells are electrically coupled through gap junctions (GJs). We consider junctional gate dynamics that depend on intercellular potential. find different GJs tissue can end up two states: low conducting state and high state. first present evidence dynamical multistability occurs by setting specific parameters GJ dynamics. Subsequently, explain how is direct consequence stability problem reducing system’s dimensions. The conductance dispersion usually large time scale, i.e., thousands heartbeats. full model simulations computationally demanding, derive simplified allows for reduction computational cost four orders magnitude. This reproduces nearly quantitatively results provided original model. discrepancies between models due to model’s lack spatial correlations. provides valuable tool explore over very long scales. That highly relevant studying diseases develop scale compared basic heartbeat. As brain, plasticity remodeling crucial determining wave propagation’s stability.