(A) Transmembrane voltage evolution from the leading pacemaker site (LPS) to the CT across the SEP. (B) Current traces for the L-type calcium current (ICaL), rapid delayed potassium rectifier current (IKr), slow delayed potassium rectifier current (IKs), sodium-calcium exchanger (NCX), sodium current (INa), and hyperpolarization-activated current (If). (C) Biomarkers measured at different locations along the depolarization path from the LPS to the CT. (D) Sodium channel activation (m) and inactivation (h) gate probability. (E) Normalized absolute difference between the reference model and model L2. (F) Net charge flux of different currents across the cell membrane. To see this figure in color, go online.