Impact of Elastin Mediated Vascular Stiffness on End Organs

Elasticity in the aorta buffers the body from damage due to pulsatile blood flow. Data from humans and mice show that with increasing age, vessels lose elasticity and become stiff. Vascular stiffness is associated with progressive cognitive impairment and dementia in aging adults, but little is known about the effects of early-onset/congenital vascular stiffness. Similarly, elastin-mediated arteriopathy in the form of stenosis has the potential to impact additional end organs such as the heart, lungs, gut, skeletal muscle and kidney causing feeding and exercise intolerance, as well hypertension. This study evaluates the impact of elastin arteriopathy and vascular stiffness on end organs. Following consent, the investigators will work with the subjects and their caregivers to determine which tests are most appropriate for the patient based on their age/capabilities and preferences and may include: * testing of cognitive and neurobehavioral abilities as well as measures of general health and well being * undergo non-invasive measurements of vascular stiffness * undergo brain imaging by MRI * undergo echocardiogram * undergo ECG * undergo 24-hour ambulatory electrocardiogram monitor * undergo ultrasound imaging and flow studies of various vascular beds and tissues * undergo CT angiogram of relevant vessels * undergo non-invasive tissue oxygenation and endothelial functional assessment with near infrared spectroscopy (NIRS) of the limbs and/or head/brain (fNIRS) * perform a 6 minute walk test * perform pulmonary function tests * receive an eye exam and Optical coherence tomography (OCT) * give blood/urine for relevant laboratories * evaluate biomechanical properties of skin * evaluate baseline fitness information using a fitness tracker * complete medica photography evaluating relevant features of the condition * receive a dental examination and dental photography Visits may be conducted in person at the Clinical Center, by telehealth, or with a combination of in person and telehealth, at the discretion of the study team. All telehealth activities will be performed according to HRPP Policy 303 and only testing that can be performed at home (e.g. clinical consultations, neurobehavioral testing, fitness tracking, ambulatory ecg monitoring, and photography) will be selected. The other tests require the individual to be on site at the CC. Consequently, some participants may have certain consultations at home and other testing on site to limit time in the CC Additionally, the study will request permission to review the participant's medical records to obtain additional information about general and cardiovascular health. For individuals with supravalvular aortic stenosis (SVAS) or Williams syndrome (WS), the clinical report confirming the individuals diagnosis will be reviewed when available.