Home > Encyclopedia of Medicine > Valvular Heart Disease

Definition

Valvular heart disease refers to several disorders and diseases of the heart valves, which are the tissue flaps that regulate the flow of blood through the four chambers of the heart.

Description

The human heart consists of four chambers—two upper chambers (the atria) and two lower chambers (the ventricles)—that are responsible for pumping blood. The heart valves are like one-way doors, which open and close with each beat of the heart, controlling the blood flow from one chamber to the next. Each of these valves is made up of a few thin folds of tissue. When functioning correctly, they keep blood from flowing backwards into a chamber when closed.

The four valves function in the following manner:

• The mitral valve is located between the left atrium and the left ventricle. It is the only valve with two flaps, or cusps.
• The tricuspid valve is located on the right side of...