What is the mitral valve?


The mitral valve—one of four valves in the heart—is the inflow valve between the lungs and the main pumping chamber of the heart (the left ventricle). This valve allows blood to enter the heart from the lungs when the heart muscle is relaxing and also prevents backflow of blood when the heart squeezes.

The mitral valve is one of the two main valves on the left side of the heart. Normally, the mitral valve has two flaps (leaflets) that open and close, allowing blood to flow from the left atrium to the left ventricle and preventing it from flowing backward into the left atrium and lungs.

This content originally appeared online in "The Patient Guide to Heart, Lung, and Esophageal Surgery" from the Society of Thoracic Surgery.

The mitral valve is the inflow valve for the left ventricle. It closes when the ventricle squeezes blood out to the body and then opens to let more blood into the ventricle.

Dr. Mehmet Oz, MD
Cardiologist (Heart Specialist)

The mitral valve is located on the left side of the heart. Blood flows from the lungs into the left atrium on the top of the heart, through the mitral valve into the left ventricle on the bottom.


Continue Learning about Heart and Circulatory System

Heart and Circulatory System

Heart and Circulatory System

Your circulatory system is made up of your heart and three main types of blood vessels -- arteries, veins and capillaries. Your heart is at the center of the system, acting as a pump to distribute nutrient- and oxygen-rich blood t...

hrough your body; it then takes away carbon dioxide and other waste your body doesn't need. Signs of poor circulation include cold hands and feet, numbness, dizziness, migraines, varicose veins and pain in your feet or legs. Untreated, poor circulation can lead to stroke, high blood pressure, kidney damage and other diseases. Learn more about your heart and circulatory system with expert advice from Sharecare.

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.