Pulmonary Stenosis

Pulmonary stenosis is when the leaflets of the pulmonary valve are fused or thick, making the pulmonary valve narrow. The pulmonary valve is the entryway from the heart to the pulmonary artery. It prevents blood from flowing back into the heart when it is squeezing blood out to the lungs.

Blood flows through the pulmonary valve into the pulmonary artery where it is taken to the lungs to become oxygenated.

A normal pulmonary valve is made up of three thin leaflets. A narrow valve means the heart has to work more to pump enough blood to the lungs.

Pulmonary stenosis can be trivial, mild, moderate, severe or critical. There are different types of pulmonary stenosis: below the valve, at the level of the valve, or above the valve.

Valvar pulmonary stenosis is thick or fused leaflets of the valve.

Subpulmonary stenosis is a thick area below the valve usually made of muscle. It does not respond as well to stretching with a balloon and usually needs surgery to open up the narrow area.

Supravalvar pulmonary stenosis is a narrowing of the blood vessel above the valve. Sometimes the vessel can be stretched with a balloon, but if the vessel is stiff and won't stretch, surgery may be necessary (see Treatments below) But sometimes, the vessel is stiff and won’t stretch. If this is true, surgery may be needed to open up the narrow area.

Treatments

Pulmonary stenosis in most cases is treated with balloon valvuloplasty, performed in the cardiac catheterization lab. Pediatric interventional cardiologists guide a thin tube into the heart through a vein in the leg. A balloon on the end of the catheter is inflated to open up the narrow valve. Sometimes, in newborns, the blood vessels in the umbilical cord are used as the place where the catheters are inserted and advanced toward the heart.

Valvotomy is a surgical procedure to separate fused leaflets in the pulmonary valve if the valve does not improve with dilation.

Treatment for supravalvar pulmonary stenosis may include stretching the narrowed blood vessel with a balloon. If the vessel is stiff and won't stretch, surgery may be necessary.

Surgical treatment is used for subpulmonary stenosis.