Electrophysiological models for the heterogeneous canine atria: Computational platform for studying rapid atrial arrhythmias

Heterogeneity in the electrical action potential (AP) properties can provide a substrate for atrial arrhythmias, especially at rapid pacing rates. In order to quantify such substrates, we develop a family of detailed AP models for canine atrial cells. An existing model for the canine right atrial (RA) myocyte was modified based on electrophysiological data from dog to create new models for the canine left atrium (LA), the interatrial Bachmann´s bundle (BB), and the pulmonary vein (PV). The heterogeneous AP models were incorporated into a tissue strand model to simulate the AP propagation, and used to quantify conditions for conduction abnormalities (primarily, conduction block at rapid pacing rated) in the canine atria.