What serves as the collecting system for most superficial veins of the heart?

The coronary sinus serves as the collecting system for most superficial veins of the heart. This structure is a large venous channel located on the posterior surface of the heart, specifically in the atrioventricular (AV) sulcus, and it is responsible for draining blood from the myocardium, which includes the great cardiac vein, middle cardiac vein, and small cardiac vein, among others.

The coronary sinus empties directly into the right atrium, allowing it to play a crucial role in returning deoxygenated blood from the heart muscle itself back into the circulatory system. This is essential for maintaining proper cardiac function, as it ensures that the blood supply to the heart muscle is efficiently managed, especially during the process of coronary circulation.

The other choices refer to important components of the circulatory system but do not serve the primary function of collecting blood from the superficial veins of the heart. For example, while the right atrium is where deoxygenated blood from the body and the coronary sinus enters, it does not act as a collecting system for the veins themselves. The azygous vein primarily drains blood from the thoracic region and does not have a role in collecting blood from the heart. Lastly, the vena cava comprises the superior and inferior vena