AEMCA Practice Exam

Where does the coronary sinus empty its blood?

1. Left ventricle

2. Pulmonary artery

3. Right atrium

4. Aorta

The correct answer is: Right atrium

The coronary sinus plays a crucial role in cardiac circulation by collecting deoxygenated blood from the myocardium, which is the heart muscle, and returning it to the heart. Specifically, the coronary sinus empties its blood into the right atrium of the heart. This is significant because the right atrium is responsible for receiving deoxygenated blood from the body through various veins, and the blood from the coronary sinus adds to this returning blood flow. The reason the choice is appropriate is that it accurately reflects the normal anatomical and physiological path of venous blood returning from the coronary circulation. Understanding this pathway is essential for grasping how the heart’s circulation system functions and how blood is processed within the heart's chambers. Other choices represent incorrect destinations for the blood collected by the coronary sinus. The left ventricle is where oxygenated blood is pumped to the body, the pulmonary artery carries deoxygenated blood to the lungs for oxygenation, and the aorta distributes oxygenated blood to the systemic circulation. None of these options relate to where the blood from the coronary sinus ultimately goes; instead, they correspond to different functions and paths within the circulatory system.