What does mitral valve do?

The mitral valve separates the left atrium (the heart's upper left chamber) from the left ventricle (the heart's lower left chamber). It acts like a one-way valve to ensure that oxygenated blood flows in one direction, from the atrium to the ventricle.

This valve is made of tissue and is structured to have two flaps or leaflets. The leaflets open as the heart fills the left atrium, then when the heart contracts and the ventricle squeezes blood out through the aorta (the main artery in the body), the valve leaflets press together and close to stop blood from flowing back into the atrium.

The mitral valve is one of four heart valves working in coordination with the heart chambers to pump oxygen-rich and oxygen-depleted blood throughout the body.