Lead aVL on electrocardiogram: emerging as important lead in early diagnosis of myocardial infarction?

Although a diagnosis of acute myocardial infarction (AMI) that mandates emergency reperfusion therapy requires ST-segment elevation greater than 1 mm in at least 2 contiguous leads, some of the early electrocardiogram (ECG) changes of AMI can be subtle. Any ST-segment depression or T-wave inversion in lead aVL may be implicated in left anterior descending artery lesion or early reciprocal changes of inferior wall myocardial infarction, particularly when the clinical context suggests ischemia. Early recognition of reciprocal changes and serial ECG help initiate early appropriate intervention. Heightened awareness of ST segment and T-wave changes in lead aVL is of paramount importance to quickly identifying life-threatening condition.