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. Genetics
Supravalvular aortic stenosis is associated with genetic damage at the Elastin gene locus on chromosome 7q11.23. Fluorescent in situ hybridisation techniques have revealed that 96% of patients with Williams syndrome, where supravalvular aortic stenosis is characteristic, have a hemizygous deletion of the Elastin gene. Further studies have shown that patients with less extensive deletions featuring the Elastin gene also tend to develop supravalvular aortic stenosis

Pathophysiology
Supravalvular aortic stenosis is due to diffuse or discrete narrowing of ascending aorta. The murmur associated with it is systolic murmur and is similar in character to valvular aortic stenosis murmur but commonly present at 1st Intercostal space (ICS) on the right. Individuals with this anomaly may have unequal carotid pulses, differential blood pressure in upper extremities and a palpable thrill in Suprasternal notch. Individuals with significant supravalvular AS chronically may develop left ventricular hypertrophy and also are at risk of developing coronary artery stenosis. With increased metabolic demands (e.g. exercise) such individuals may develop subendocardial or myocardial ischemia due to increased myocardial oxygen demand and seek medical help with symptoms of exercise induced angina. Diagnosis
Treatment


== References ==
Disease states such as insufficient or malfunctioning platelets, other coagulation deficiencies, or vascular disorders, such as venous blockage associated with severe allergies can lead to the formation of purpura which is not to be confused with trauma-related bruising/contusion. If the trauma is sufficient to break the skin and allow blood to escape the interstitial tissues, the injury is not a bruise but bleeding, a different variety of hemorrhage. Such injuries may be accompanied by bruising elsewhere. Signs and symptoms
Bruises often induce pain immediately after the trauma that results in their formation, but small bruises are not normally dangerous alone. Sometimes bruises can be serious, leading to other more life-threatening forms of hematoma, such as when associated with serious injuries, including fractures and more severe internal bleeding. The likelihood and severity of bruising depends on many factors, including type and healthiness of affected tissues. Minor bruises may be easily recognized in people with light skin color by characteristic blue or purple appearance (idiomatically described as "black and blue") in the days following the injury. Hematomas can be subdivided by size. By definition, ecchymoses are 1 centimetres in size or larger, and are therefore larger than petechiae (less than 3 millimetres in diameter) or purpura (3 to 10 millimetres in diameter). Ecchymoses also have a more diffuse border than other purpura. A broader definition of ecchymosis is the escape of blood into the tissues from ruptured blood vessels. The term also applies to the subcutaneous discoloration resulting from seepage of blood within the injured tissue.