Right atrioventricular valve (Tricuspid valve)
The tricuspid valve forms the boundary between the right ventricle and atrium. Deoxygenated blood enters the right side of the heart via the inferior and superior vena cava. Blood collects into the right atrium, and it must flow through the tricuspid valve before entering the right ventricle. Then, blood exits the heart via the pulmonary artery, which transits blood to the lungs for oxygenation. The term "tricuspid" refers to how the valve is constructed. It contains three flap-like cusps, and when closed these cusps keep blood from regressing back into the right atrium. This regression is known as tricuspid regurgitation, and it is common in diseased hearts, often weakened by drug abuse. The tricuspid valve is not the only cardiac valve that is "tricuspid" in nature. On the left side of the heart, the aortic valve also features three cusps. This valve serves a boundary between the left ventricle and the aorta. There is some congenital variation, however; some people are born with two-cusp-only aortic valve.
Written and medically reviewed by the Healthline Editorial Team
In Depth: Right atrioventricular valve (Tricuspid valve)