Mechanisms of heterogeneous electrophysiology in heart and the relation to electropharmacology and toxicology

It is believed that cardiac electrophysiological properties are not homogeneous, and the heterogeneity exists between pacemaker and conduction cells, atrial and ventricular cells, and among endocardium, midmyocardium, and epicardium of the transmural ventricular wall. The heterogeneous electrophysiology is related to the differential distribution and expression of transmembrane ionic channels. The present review involves literatures regarding the intrinsic biological basis of cardiac heterogeneous electrophysiology.