From which artery does the Posterior Descending Artery originate?

The Posterior Descending Artery (PDA) typically originates from the Right Coronary Artery (RCA) in the majority of individuals, particularly in those with a right dominant coronary circulation, which is the most common anatomical configuration. The PDA runs in the posterior interventricular sulcus and supplies blood to the inferior part of the heart, particularly the inferior walls of the left ventricle and the interventricular septum.

In left dominant coronary systems, the PDA can arise from the Left Circumflex Artery, but this is less common. The other arteries listed, such as the Aortic Arch and Subclavian Artery, do not give rise to the PDA. The aortic arch is the main arterial structure giving way to all major arteries supplying the upper body, but does not supply the PDA directly. The subclavian artery primarily supplies the arms and parts of the thoracic wall and does not contribute to the coronary artery system. Therefore, the correct origin of the PDA is the Right Coronary Artery, which is crucial for understanding coronary blood supply and cardiac anatomy.