noun, plural: pulmonary valves
(anatomy, cardiology) The semilunar valve that lies between the right ventricle and the pulmonary artery, and generally has three cusps that regulate the closure and opening of the valve during ventricular systole
The pulmonary valve is one of the two types of semilunar valves. The other is aortic valve. The pulmonary valve is located between the right ventricle and the pulmonary artery. Similar to aortic valve, the pulmonary valve has three cusps. The cusps regulate the opening and closure of the valve during ventricular systole. The opening of the pulmonary valve occurs when the pressure in the right ventricle rises above the pressure in the pulmonary artery. When the pulmonary valve opens the blood from the right ventricle moves into the pulmonary artery. When the pressure drops rapidly the pulmonary valve closes. When closed, the blood is prevented from flowing back into the ventricle. The closure of pulmonary valve (together with the aortic valve) accounts for the second heart sound.