What is it?
Pulmonary stenosis is tightness in the flow of blood between the right pumping chamber (right ventricle) and the lungs. The tightness is usually at the level of the pulmonary valve (valvar pulmonary stenosis), but sometimes there can be tightness before or after the valve as well. Pulmonary stenosis is a very common heart problem in children, and probably accounts for about 10% of all heart problems diagnosed during childhood.
What does it do?
In most children, pulmonary stenosis is mild, and has no important effect on the way the heart works. If pulmonary stenosis is severe, it causes a lot of extra work for the right ventricle, which can lead to problems such as cyanosis (low blood oxygen), arrhythmias (irregular heart rhythms) and congestive heart failure (higher-than-normal pressure in the veins). Pulmonary stenosis can get worse with time; generally mild pulmonary stenosis only progresses in the first 5-6 months of life – after that progression of mild pulmonary stenosis is rare. Moderate or severe pulmonary stenosis can progress throughout life.
How is it treated?
Mild or moderate pulmonary stenosis usually does not require any treatment. Generally mild to moderate pulmonary stenosis can be monitored by your cardiologist by listening through a stethoscope, although in some cases an echocardiogram (ultrasound) may be necessary from time to time. Severe pulmonary stenosis may require correction, either with a catheterization procedure using a balloon to open the tight valve, or (much less commonly) open heart surgery.
Below are some Internet sites that include more information about pulmonary stenosis. I cannot vouch for the information in these sites, but I have tried to pick out examples that are of relatively good quality.
American Heart Association
A good site to see a brief description of the different types of heart disease and the treatments available
Children's Hospital Boston
Lucile Packard Children's Hospital at Stanford