Fig. 4
From: Ionic mechanisms of ST segment elevation in electrocardiogram during acute myocardial infarction
Mechanisms of ST–T changes under ischemic conditions. a The sodium current (INa), L-type calcium current (ICaL), rapid delayed rectifier potassium current (IKr), adenosine triphosphate (ATP)-sensitive potassium current (IKATP), and action potential (AP) are shown under mild, moderate, and severe acute ischemia. During chronic ischemia, cellular activities were completely abolished. In each panel, data from the endocardial region are shown by a black line, the mid-myocardial region by a red line, and the epicardial region by a blue line. b The potential distributions in the intracellular (top row) and extracellular (second row) spaces (at the timing indicated by the blue dot in the below electrocardiogram [ECG]) are shown for mild, moderate, and severe ischemia in the acute and chronic phases. The electrical bilayers and their solid angles at the overlying electrodes are shown in the schematic (third row). The bottom panels show the ECGs (V3 lead) under each condition. The ECG under mild ischemia is compared with the normal ECG (red line). Numbers at the bottom indicate the time after the onset of ventricular activation in milliseconds