Fig. 2

Electrophysiology under normal condition and subendocardial ischemia. a Cellular electrophysiology: Action potentials (AP) and major ionic currents of the endocardial (endo), mid-myocardial (M), and epicardial (epi) cells. b Time-lapse images showing propagation of excitation in the heart (Excitation), short axis views of the potential distributions in the intracellular space and extracellular space, and the body surface potential map. Numbers indicate the time after the onset of excitation in ms. RV, right ventricle; LV, left ventricle. c 12-lead electrocardiogram. d Cellular electrophysiology under subendocardial ischemia: AP and major ionic currents of the endo, M, and epi cells. e Short axis views of the potential distributions in the intracellular and extracellular spaces during diastole (0 ms) and systole (150 ms) under subendocardial ischemia. Electrical bilayers and their solid angles at the overlying electrodes are shown in the schematics (right column). RV: right ventricle; LV: left ventricle. f 12-lead electrocardiogram. INa, sodium current; IKr, rapid delayed rectifier potassium current; IKs, slow delayed rectifier potassium current; ICaL, L-type calcium current; IK_ATP, ATP-sensitive potassium current