Abnormal ST-segment changes in anterior and inferior leads during acute inferior myocardial infarction.

Anterior and inferior ST elevation on electrocardiography (ECG) in patients with acute myocardial infarction is uncommon. ST-segment elevation due to right ventricular infarction induced by right coronary occlusion may extend from V1 to V3/V4, resembling the pattern of transmural ischemia of the anterior wall of the left ventricle. In addition, a wraparound left anterior descending (LAD) artery can produce ischemia manifesting as ST-segment elevation in the anterior and inferior leads. Our case report reveals dynamic ST-segment changes in acute inferior myocardial infarction, including the appearance of the shark fin ECG pattern, unlike what has been reported before.