Home > Medical Reference > Patient Education

Heart valves - superior view

There are four valves located in the heart. Each valve consists of either two or three folds of thin tissue. When closed, the valve prevents blood from flowing backwards to its previous location. When open the valve allows blood to flow freely. Valve problems can occur because of congenital abnormalities, rheumatoic fever, infection, or other causes.

Reviewed last on: 6/8/2008
Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.