The pulmonary valve controls the blood ?ow between the right ventri- cle and the pulmonary artery leading into the lungs . Although disease is rare, the pulmonary valve can develop regurgitation (backward leakage) or stenosis (narrowing).

Pulmonary Regurgitation

Pulmonary regurgitation is a condition in which some blood is allowed to leak back from the pulmonary artery into the right ventricle. It is usually caused by congenital (present since birth) disease or pulmonary hypertension (high blood pressure in the lungs and right side of the heart). It is often associated with congenital heart disease affecting other parts of the heart. Very rarely, infective endocarditis (see page 192) damages the valve.
Many people with some pulmonary regurgitation do not have symp- toms of the condition. Your doctor will monitor your heart regularly to ensure that the right ventricle is not becoming strained or enlarged. You will probably not need to limit your physical activities. If you have a valve that has been malformed since birth, you are at greater risk of infective endocarditis and may need to take antibiotics before dental or surgical procedures (see page 194).
If the regurgitation becomes serious, it causes the right ventricle to start to fail. Then you may experience symptoms such as shortness of breath, especially during exercise; fatigue; chest pain; or leg swelling. Arrhythmias may occur. Ask your doctor about any exercise restrictions. You may require surgery to repair or replace the valve .

Pulmonary Stenosis

Pulmonary stenosis is a condition in which the pulmonary valve (or the artery just beyond the valve) is narrowed, reducing the ?ow of blood into the lungs. It is usually present at birth and may progress in childhood or not until later in life. If it occurs later in life, it may have been caused by rheumatic fever , congenital heart disease, or infective endocarditis.
Pulmonary stenosis can be very mild or moderate, and it usually does not cause severe symptoms. Your doctor will check your heart regularly, watching for signs of strain on your right ventricle. You may not need to limit your physical activity, but you are at greater risk of infective endocarditis, so you will need to take antibiotics before having some dental and surgical procedures .
If the condition is severe, it may cause symptoms such as shortness of breath, especially during exercise; fatigue; chest pain; or rarely, a bluish skin tone. Severe stenosis could cause life-threatening failure of the right ventricle. Sometimes surgery to repair the valve is done early, dur- ing the preschool years of a child’s life. In an older person, balloon valvuloplasty is usually needed to open the valve, or rarely, valve replacement  may be necessary.