The monodomain model is a reduction of the bidomain model of the electrical propagation in myocardial tissue.
The reduction comes from assuming that the intra- and extracellular domains have equal anisotropy ratios.
Although not as physiologically accurate as the bidomain model, it is still adequate in some cases, and has reduced complexity.
The monodomain model can be formulated as follows
where is the intracellular conductivity tensor, is the transmembrane potential, is the transmembrane ionic current per unit area, is the membrane conductivity per unit area, is the intra- to extracellular conductivity ratio, and is the membrane surface area per unit volume (of tissue).