Pulmonary valve

The pulmonary valve, also known as pulmonic valve, is the semilunar valve of the heart that lies between the right ventricle and the pulmonary artery and has three cusps.

Similar to the aortic valve, the pulmonic valve opens in ventricular systole, when the pressure in the right ventricle rises above the pressure in the pulmonary artery. At the end of ventricular systole, when the pressure in the right ventricle falls rapidly, the pressure in the pulmonary artery will close the pulmonic valve.

The closure of the pulmonic valve contributes the P2 component of the second heart sound (S2).

The right heart is a low-pressure system, so the P2 component of the second heart sound is usually softer than the A2 component of the second heart sound. However, it is physiologically normal in some young people to hear both components separated during inhalation.