Question

Which of the following does NOT return blood to the right atrium of the heart?

coronary sinus
superior vena cava
pulmonary vein
inferior vena cava

Answer 1

The coronary sinus does not return blood to the right atrium of the heart. So, the correct answer is first option.

Step-by-step explanation:

The coronary sinus does NOT return blood to the right atrium of the heart. The coronary sinus drains most of the coronary veins that return systemic blood from the heart, but it does not directly empty into the right atrium. Instead, it has its own opening on the posterior surface of the atrium, slightly medially and superiorly to the opening of the inferior vena cava.

So, the correct answer is first option.