(See also Overview of Heart Valve Disorders.)
Pulmonic (pulmonary) regurgitation is leakage of blood backward through the pulmonary valve each time the right ventricle relaxes.
The pulmonic valve is in the opening between the right ventricle and the blood vessels going to the lungs (pulmonary arteries). The pulmonic valve opens as the right ventricle contracts to pump blood into the lungs. When the pulmonic valve does not close completely, some blood leaks backward into the right ventricle, termed regurgitation.
Abnormally high blood pressure in the lungs (pulmonary hypertension) is the most common cause of pulmonic regurgitation. The high pressure stresses the valve, causing it to leak. Much less common causes are infection of the valve (infective endocarditis), pulmonary artery enlargement, a birth defect of the valve, or surgery to repair a heart defect.
Pulmonic regurgitation usually causes no symptoms. Sometimes people develop swollen ankles or fatigue.
Often pulmonic regurgitation is detected during an examination done for some other reason. Through a stethoscope, doctors may hear a characteristic murmur produced by the blood leaking backward through the pulmonic valve. Echocardiography can produce an image of the leaky valve and the amount of blood leaking, so that the severity of the regurgitation can be determined.