Supravalvular aortic stenosis (SVAS) is a type of heart defect. It is characterized by a narrowing (stenosis) of the section of the aorta just above the valve that connects the aorta to the heart (aortic valve). The severity of SVAS varies from person to person.

Supravalvular aortic stenosis is a congenital obstructive narrowing of the aorta just above the aortic valve and is the least common type of aortic stenosis. It is often associated with other cardiovascular anomalies and is one of the characteristic findings of Williams syndrome. The diagnosis can be made by echocardiography or MRI.