Pulmonary Valve Stenosis
(See also Overview of Heart Defects.)
Pulmonary valve stenosis is a narrowing of the pulmonary valve (sometimes called the pulmonic valve), which opens to allow blood to flow from the right ventricle to the lungs.
The heart valve between the right ventricle and the artery to the lungs is narrowed.
In most children, the only symptom is a heart murmur, but a bluish color to the skin (cyanosis) and signs of right heart failure (such as fatigue and shortness of breath) are possible.
The diagnosis is suspected based on a heart murmur heard with a stethoscope and is confirmed with echocardiography.
Balloon valvuloplasty to open the valve or surgery to reconstruct it is sometimes needed.
In most children with pulmonary valve stenosis, the valve is mildly to moderately narrowed, making the right ventricle pump a bit harder and at a higher pressure to propel blood through the valve. Severe narrowing increases pressure in the right ventricle and prevents almost any blood from reaching the lungs. When pressure in the right ventricle becomes extremely high, oxygen-poor blood is forced through abnormal paths (usually a hole in the atrial wall [atrial septal defect]) instead of the pulmonary artery, causing right-to-left shunting. In right-to-left shunting, oxygen-poor blood from the right side of the heart mixes with oxygen-rich blood that is pumped from the left side of the heart to the rest of the body. The more oxygen-poor blood (which is blue) that flows to the body, the bluer the body appears.
Most children with pulmonary valve stenosis have no symptoms. Severe pulmonary valve stenosis may cause the skin to have a bluish coloration (cyanosis), particularly of the lips, tongue, skin, and nail beds. Children also may have fatigue and/or shortness of breath (see Figure: Heart Failure: Pumping and Filling Problems).
Doctors often suspect pulmonary stenosis if they hear a certain kind of heart murmur while listening with a stethoscope. A heart murmur is a sound created by turbulent blood flow through narrowed or leaking heart valves or through abnormal heart structures.
Echocardiography (ultrasonography of the heart) confirms the diagnosis.
Treatment depends on the severity of the infant's symptoms.
Severe disease that causes cyanosis in newborns is treated by giving a prostaglandin by vein (intravenously). The prostaglandin keeps the ductus arteriosus open, thus sending extra blood to the lungs to increase the level of oxygen in the infant's blood. This drug is usually given until the valve can be repaired with balloon valvuloplasty or a surgical procedure. For balloon valvuloplasty, a thin tube (catheter) with a balloon at its tip is passed through a blood vessel in the arm or leg into the narrowed valve. The balloon is inflated and used to widen the narrowed opening of the valve.
Doctors usually also do balloon valvuloplasty in infants who do not have cyanosis if the valve is moderately or severely narrowed
If the valve is very small or markedly thickened, balloon valvuloplasty may not be sufficient. Surgery is then used to open or reconstruct the pulmonary valve.
Some children need to take antibiotics before visits to the dentist and before certain surgeries (such as on the bowel or bladder). These antibiotics are used to prevent serious heart infections called endocarditis.