ST elevations in leads II, III, and aVF indicate which type of myocardial infarction?

ST elevations in leads II, III, and aVF indicate an inferior myocardial infarction (MI). These leads are primarily associated with the inferior wall of the heart, which is supplied by the right coronary artery in most individuals. When there is significant occlusion of this artery, it can lead to ischemia and injury in the inferior wall, resulting in the characteristic ST segment elevation observed in these specific leads on an electrocardiogram (ECG).

This finding is clinically significant as it guides the management and treatment of the patient. Recognizing an inferior MI is important because it may also be associated with specific complications, such as right ventricular MI, which can require additional interventions.

The other options correspond to different areas of myocardial damage: anteroseptal MIs typically involve leads V1-V4, lateral wall MIs are indicated by changes in leads I, aVL, V5, and V6, while posterior wall MIs may present with ST depression in the anterior leads (V1-V3) and tall R waves in those same leads. Each type of MI requires tailored management, making understanding the lead patterns critical in emergency medicine.