Occlusion of anterior descending branch of left coronary artery

Occlusion of the anterior descending branch of left coronary artery will lead to infarction of which area?

A. Anterior wall of left ventricle
B. Posterior part of the interventricular septum
C. Lateral part of the heart
D. Inferior surface of the right ventricle
Answer is A. Anterior wall of left ventricle.

In its initial course, the left coronary artery gives off a circumflex coronary artery and then continues as the anterior descending branch.

The following is a description of the frequencies of critical narrowing and thrombosis of each of the 3 main arterial trunks and the corresponding sites of myocardial lesions:

• Left anterior descending coronary artery (40-50%, most common) - Lesions in anterior wall of left ventricle near apex and anterior 2/3 of interventricular septum.
• Right coronary artery (30-40%) - Lesions in inferior or posterior wall of left ventricle, posterior 1/3 of interventricular septum, and posterior right ventricular free wall in some cases.
• Left circumflex coronary artery (15-20%) - Lesions in lateral wall of left ventricle