Pulmonary StenosisNancy McDaniel M.D.The heart in this defect has four chambers and four valves. The defect is that the valve leading to the lung artery is too small, too thick or does not open completely. This causes the right pumping chamber of the heart to have to work harder than normal to push the blood to the lungs. Mild levels of narrowing are tolerated very well, but severe blockage of the valve would require a heart catheterization or surgery to relieve the narrowing. Once the blockage is removed the child generally has normal activity.
 Normal Heart  |