Medical Mystery of the Week

A patient (see image, below) is referred to you for evaluation of a heart murmur. On your exam, the systolic BP in the right arm is 10 mm Hg higher than the left arm. You hear a systolic murmur over the aortic area which radiates loudly to the right common carotid artery. The patient's IQ is lower than expected for his age group. What is your diagnosis, what test(s) would you order to confirm your suspicions, and what treatment, if any, do you recommend?

DIAGNOSIS: Supravalvular aortic stenosis (SVAS).

SVAS is a systemic elastin arteriopathy that disproportionately narrows the supravalvular aorta. SVAS may be present in a nonsyndromic condition or in syndromic conditions such as the Williams-Beuren syndrome as seen in the presented case.The anatomical findings of SVAS can include congenital narrowing of other arteries, including branches of the pulmonary and coronary arteries.Elastin arteriopathy is genetically heterogeneous and occurs as a consequence of haploinsufficiency of the elastin gene on chromosome 7q11.23 owing to either a microdeletion of the entire chromosomal region or elastin point mutations. The presented case's appearance is typical of the William-Beuren syndrome with osteo-mandibular asymmetries, long neck, large ears, and accompanying mental deficfiency