Which artery passes around to supply the posterior surface of the heart, including the septum?

Which artery passes around to supply the posterior surface of the heart, including the septum?

• A. Circumflex artery
• B. Anterior descending artery
• C. Right coronary artery
• D. Posterior descending artery

Answer: (A)

The circumflex artery travels in the left coronary sulcus and then wraps around to the posterior surface of the heart. In hearts where the left coronary system contributes the posterior descending artery (left-dominant circulation), the circumflex gives branches that supply the posterior interventricular area and the posterior aspect of the septum. So, this artery can reach the back of the heart and contribute to the blood supply of the posterior septum, making it the best answer for a vessel that passes around to the posterior surface and septum. The other arteries mainly supply the anterior wall (anterior descending) or rely on the right coronary for the posterior septum in most individuals (right-dominant pattern), with the posterior descending artery typically arising from the RCA rather than traveling around to the back on its own.

The circumflex artery travels in the left coronary sulcus and then wraps around to the posterior surface of the heart. In hearts where the left coronary system contributes the posterior descending artery (left-dominant circulation), the circumflex gives branches that supply the posterior interventricular area and the posterior aspect of the septum. So, this artery can reach the back of the heart and contribute to the blood supply of the posterior septum, making it the best answer for a vessel that passes around to the posterior surface and septum. The other arteries mainly supply the anterior wall (anterior descending) or rely on the right coronary for the posterior septum in most individuals (right-dominant pattern), with the posterior descending artery typically arising from the RCA rather than traveling around to the back on its own.