tricuspid valve, a valve with three main cusps situated between the right atrium and right ventricle of the heart. The cusps of the tricuspid valve include the ventral, dorsal, and medial cusps. The cusps are composed of strong fibrous tissue and are anchored to the papillary muscles of the right ventricle by several tendons. As the right and left ventricles relax during the diastolic phase of the heartbeat, the tricuspid valve opens, allowing blood to flow into the ventricle. In the systolic phase of the heartbeat, both blood-filled ventricles contract, pumping out their contents, while the tricuspid and mitral valves close to prevent any backflow. Also called right atrioventricular valve. Compare aortic valve, mitral valve, pulmonary valve, semilunar valve. See also atrioventricular (AV) valve, heart valve.
