Aortic Supravalvular Stenosis (SVAS) is a rare genetic disorder where the beginning portion of the aorta is abnormally narrow. The aorta is the large blood vessel leaving the heart to deliver oxygen-rich blood to the body. This narrowing can cause the heart to work harder and can sometimes lead to ventricular hypertrophy, or enlargement of the lower chambers of the heart. If left untreated, it can cause shortness of breath, chest pain, or even heart failure. SVAS generally has a 50% chance of passing on to an affected individual's children, so early diagnosis and counseling is important. It is almost always a result of a harmful change in genetic material which instructs thte body how to make elastin, the protein which provides body tissue its elasticity. It is often associated with Williams-Beuren syndrome, which includes mental retardation, a peculiar face, and high blood calicum levels. It can be diagnosed with a physical exam, including listening to the heart with a stethoscope for a murmur, and an imaging test called an echocardiogram. Regular follow-up is recommended (every 6 months for infants and each year in children) in order to monitor the evolution of the stenosis, which can be corrected with surgery.