A 52-year-old woman was referred for surgical treatment of a symptomatic aortic stenosis. Her medical history included unexplored mild mental retardation. Physical examination revealed high blood pressure (140/87 mmHg) with a systolic aortic 3/6 murmur and a distinctive facial appearance (spaced teeth, long philtrum and sunken nasal bridge), suggestive of Williams’s syndrome. Transthoracic echocardiography showed a calcified bicuspid aortic valve with mild insufficiency, a supravalvular aortic stenosis (SVAS) with a mean gradient of 78 mmHg and normal left ventricular systolic function ( Fig. 1 ). Pulmonary stenosis, mitral involvement and ventricular septal defect were not found. A computed tomography scan confirmed SVAS (SVAS area, 1.35 cm 2 ) ( Fig. 2 ). There was no aortic coarctation. An angiogram showed a slight right coronary artery and blood analysis revealed normal calcaemia. The deletion of an elastin allele was subsequently found by fluorescence in situ hybridization and confirmed the 7q11.23 chromosomal microdeletion. A tight SVAS was found at the sinotubular junction after median sternotomy. The aortic valve was bicuspid type I with bulky calcifications. The non-coronary sinus was fully split then the sinotubular junction was enlarged using a Dacron patch to allow aortic valve replacement with a mechanical prosthesis (On-X 19 mm) ( Fig. 3 ). The postoperative course was uneventful and the patient was discharged 11 days postoperatively.
