Effects of electrophysiological remodeling in human right atrium: a simulation study

Atrial fibrillation (AF) induces variations in channel characteristics of human atrial myocytes. Data from experimental AF studies was incorporated in a computational model It was used to investigate the effects of electrophysiological remodeling on myocardial behavior This model was integrated in a schematic 2D model of human right atrium including the sinoatrial node, crista terminalis, pectinate muscles, and the atrial working myocardium. Heterogeneous, anisotropic conduction was reconstructed with the monodomain approach. In both normal and pathological case, the models were excited with 68 bpm by the sinoatrial node depolarizing spontaneously. A slightly decreased conduction velocity was reconstructed in the remodeling case. The repolarization period was abbreviated from physiologically 325 ms to 145 ms. A shortened effective refractory period (ERP) and an attenuated ERP-rate relationship were identified. Both factors provide a substrate for AF recurrence