The aortic valve, located at the beginning of the aorta, opens and closes to regulate blood flow into the aorta.
Stenosis means narrowing.
This may vary from a thin layer of extra tissue to large bundles of heart muscle. The left ventricle works harder to pump blood past the narrow region into the aorta. With time, the extra work stresses the left ventricle, causing it to enlarge. Many children with subaortic stenosis have no symptoms. If an infant has severe stenosis, they can develop rapid heart rate, rapid breathing, and poor feeding.