Question

question 18

the circumflex artery and the anterior interventricular artery are branches of the

a) right coronary artery.
b) left coronary artery.
c) great cardiac vein
d) coronary sinus.
e) aorta.

Explanation:

Identify the target vessels

The question asks for the parent vessel that gives rise to both the circumflex artery and the anterior interventricular artery (also known as the left anterior descending artery, or LAD).

Analyze the coronary anatomy

The heart's myocardium is supplied with oxygenated blood by the right and left coronary arteries, which arise directly from the ascending aorta.

Trace the branches of the left coronary artery

The left coronary artery (LCA) emerges from the left aortic sinus and quickly divides into two primary branches:

• The anterior interventricular artery (LAD), which runs in the anterior interventricular sulcus toward the apex.
• The circumflex artery, which curves to the left in the coronary sulcus to supply the left atrium and left ventricle.

Evaluate the given options

• A) right coronary artery: Gives rise to the marginal artery and the posterior interventricular artery.
• B) left coronary artery: Correct, as it branches directly into the circumflex and anterior interventricular arteries.
• C) Great cardiac vein: This is a venous drainage vessel, not an artery.
• D) coronary sinus: This is the main venous channel draining the heart muscle into the right atrium.
• E) aorta: While the coronary arteries arise from the aorta, the circumflex and anterior interventricular arteries are direct branches of the left coronary artery itself, not the aorta directly.

Answer:

• (A) right coronary artery.
• (B) left coronary artery. (Correct answer)
• (C) Great cardiac vein
• (D) coronary sinus.
• (E) aorta.