When ST-segment elevation is noted in leads II, III, and aVF, which myocardial ischemia is most likely present?

The presence of ST-segment elevation in leads II, III, and aVF indicates that the inferior wall of the heart is experiencing myocardial ischemia. These leads correspond to the inferior part of the heart, which is primarily supplied by the right coronary artery (RCA) in a right-dominant system.

When an inferior wall myocardial infarction occurs, it typically manifests as ST-segment elevation in these specific leads. This elevation indicates an acute phase of myocardial injury, where the heart muscle is not receiving adequate blood flow, leading to the characteristic patterns seen on an electrocardiogram (ECG).

The other types of myocardial ischemia do not relate to this specific observation. Anterior wall ischemia would be indicated by changes in leads V1 to V6, while lateral wall ischemia would be reflected through leads I, aVL, V5, and V6. Posterior wall ischemia typically requires suspicion of reciprocal changes in the anterior leads, which would not be evident with elevation in the inferior leads alone. Therefore, the ST-segment elevation in the inferior leads clearly points to inferior wall myocardial ischemia.