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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
All open coronary sinus except?
assistant
The correct answer is  Ans. B. Anterior cardiac veinThe coronary sinus is a collection of veins joined together to form a large vessel that collects blood from the heart muscle. The coronary sinus drains into the right atrium, at the coronary sinus orifice, an opening between the inferior vena cava and the tricuspid valve. It returns blood from the heart muscle, and is protected by a semicircular fold, the valve of coronary sinus (Thebesian valve).