Figure 15.

The impact of severe hypokalemia on the population of 1,000 human ventricular epicardium APs with increased I_Ca,L window in the presence of CQ and AZM. (A) The effect of CQ 5 μM in combination with AZM 20 μM in the absence of hypokalemia ([K⁺]_o = 5.4 mM; left panel) and in the presence of severe hypokalemia ([K⁺]_o = 2.0 mM; right panel). (B) A 3 mV shift in the steady-state activation and inactivation of I_Ca,L was introduced in the human ventricular epicardium model to increase the I_Ca,L window (shift from black to purple lines). (C) The incidence of EAD/RF observed in the population-based study (as percentage of models). EAD, early afterdepolarization; I_Ca,L, L-type Ca²⁺ current; ISO, isoproterenol; RF, repolarization failure; V_M, membrane potential.