Figure 3 Placement of leads for derived 12-lead electrocardiography. EASI lead placement: E, electrode placed on the lower part of the sternum, level with the fifth intercostal space; A, electrode placed at the level of the fifth intercostal space, on the left midaxillary line; S, electrode placed on the upper part of the sternum; I, electrode placed at the fifth intercostal space, on the right midaxillary line. The fifth ground electrode can be placed anywhere.