In acute anterior wall myocardial infarction, the ECG changes specifically in leads V3, V4 and V5.
Coronary artery blood supply to the myocardium is distributed regionally, and an occlusion of a coronary artery causes necrosis in a part of the myocardium it supplies, so its ECG changes are segmental. Therefore, ischemic injury is seldom confined to a single lead, but should occur in at least two or more adjacent leads.
The anterior interventricular wall corresponds to leads V1-V3, the forearm corresponds to leads V3-V5, and the extensive anterior wall corresponds to leads V1-V6 and is supplied by the left anterior descending vessel. The anterior-posterior wall corresponded to leads V7-9 and was supplied by the left echogenic branch or right coronary vessels. The infarct site determined by ECG broadly identifies the infarct-related vascular lesion and helps in treatment.
An abnormal ECG examination requires aggressive diagnosis and treatment.