What is the name of the small flap of tissue that protects the opening of the Coronary Sinus?

The small flap of tissue that protects the opening of the coronary sinus is known as the Thesbian valve. This structure is located at the entrance of the coronary sinus into the right atrium and plays a role in directing blood flow. The valve facilitates the unidirectional flow of blood from the coronary sinus into the right atrium while preventing backflow, especially during atrial contraction. Understanding the anatomy and function of the Thesbian valve is crucial for interpreting cardiac blood flow dynamics and assessing conditions related to coronary circulation. The other choices, while important valves within the heart, do not serve this specific protective function at the coronary sinus opening.