Figure S9.

Heterogeneous GJ size distribution can impact cardiac conduction.(A) Example of mesh incorporating larger GJs at the ID edge. The distribution of these larger GJs was defined as occupying the peripheral 10% of the ID and having an average GJ length and fraction of membrane occupied as 50% greater than baseline values in the interplicate region. (B) CV in the tissue model incorporating meshes with larger GJs at ID edges, compared with the monodomain and baseline cleft network model, in the case of strong GJ coupling. The large GJs at the edge slow conduction compared with the regular mesh. (C) In contrast, in the case of weak GJ coupling, CV is increased in tissue with IDs incorporating larger peripheral GJs. Both effects arise because the larger GJs at ID edges reduce conductance to the extracellular bulk space, thus amplifying ephaptic coupling effects, which slow conduction for strong GJ coupling and enhance conduction for weak GJ coupling.