Which enlarged vein collects blood from the cardiac veins and empties into the right atrium?

Which enlarged vein collects blood from the cardiac veins and empties into the right atrium?

• A. Coronary Sinus
• B. Superior Vena Cava
• C. Inferior Vena Cava
• D. Aorta

Answer: (A)

The main concept here is how the heart’s own venous blood returns to the heart. The coronary sinus is an enlarged vein that runs in the posterior part of the coronary sulcus and serves as the primary drainage point for the heart’s veins. It collects blood from the cardiac veins, such as the great cardiac vein and middle cardiac vein, and then empties into the right atrium through its opening in the atrial wall. A small valve-like guard at the coronary sinus ostium helps regulate this flow. This differs from the other vessels listed: the superior and inferior vena cavae bring systemic venous blood from the body into the right atrium, not drainage from the heart muscle itself; the aorta is an artery that carries oxygenated blood away from the left ventricle to the body, not venous return.

The main concept here is how the heart’s own venous blood returns to the heart. The coronary sinus is an enlarged vein that runs in the posterior part of the coronary sulcus and serves as the primary drainage point for the heart’s veins. It collects blood from the cardiac veins, such as the great cardiac vein and middle cardiac vein, and then empties into the right atrium through its opening in the atrial wall. A small valve-like guard at the coronary sinus ostium helps regulate this flow.

This differs from the other vessels listed: the superior and inferior vena cavae bring systemic venous blood from the body into the right atrium, not drainage from the heart muscle itself; the aorta is an artery that carries oxygenated blood away from the left ventricle to the body, not venous return.