An anterior wall myocardial infarction is characterized by ST elevations in which leads?

An anterior wall myocardial infarction is characterized by ST elevations in which leads?

• A. V1–V4
• B. II, III, aVF
• C. V5–V6
• D. I, aVL

Answer: (A)

Understanding how ECG leads map to heart regions is essential. An anterior wall myocardial infarction involves the front part of the left ventricle, fed mainly by the left anterior descending artery. Injury currents and the resulting ST elevations project toward the anterior chest, so the precordial leads overlie the anterior surface and show the changes most clearly—classically in V1 through V4 (with V3–V4 often the most prominent). In contrast, ST elevations in II, III, and aVF point to the inferior wall, those in I and aVL reflect the high lateral wall, and V5–V6 reflect the lateral wall as well. Thus, anterior wall infarction is best characterized by ST elevations in the chest leads V1–V4.

Understanding how ECG leads map to heart regions is essential. An anterior wall myocardial infarction involves the front part of the left ventricle, fed mainly by the left anterior descending artery. Injury currents and the resulting ST elevations project toward the anterior chest, so the precordial leads overlie the anterior surface and show the changes most clearly—classically in V1 through V4 (with V3–V4 often the most prominent). In contrast, ST elevations in II, III, and aVF point to the inferior wall, those in I and aVL reflect the high lateral wall, and V5–V6 reflect the lateral wall as well. Thus, anterior wall infarction is best characterized by ST elevations in the chest leads V1–V4.