The bicuspid valve, also known as the mitral valve or left atrioventricular valve, is a dual-flap valve in the heart that lies between the left atrium and the left ventricle. The mitral valve (not to be confused with the congenital bicuspid aortic valve) and the tricuspid valve are known collectively as the atrioventricular valves because they lie between the atria and the ventricles of the heart and control the flow of blood.

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