The best available evidence suggests that overall prevalence of congenital heart defect (CHD) in the adult population is about 3000 per million [
1]. The population of adults with a congenital heart defect is increasing, due to improved survival after cardiac surgery [
1,
2]. Supravalvular aortic stenosis (SVAS) is the least common form of left ventricular outflow tract (LVOT) obstruction. In Kitchiner’s series the incidence of LVOT obstruction was 6.1/10,000 live births. In his series of 313 patients with LVOT obstruction, SVAS occurred in 7.7% of the cases [
3]. In 51 children, catheterised for congenital aortic stenosis, Liu detected 7 cases (13.7%) of SVAS [
4]. SVAS involves a focal or diffuse narrowing of the ascending aorta, starting at the sinotubular (ST) junction. It can be a feature of the Williams-Beuren syndrome (WBS) [
5], an autosomal dominant multisystem disorder involving besides cardiovascular abnormalities, also mental retardation, characteristic facial appearance (‘elfin face’) and occasional idiopathic hypercalcaemia. SVAS can also occur in an autosomal inherited form without the features of the WBS or in a rare sporadic form [
6]. In all three types, there is a mutation of the elastin gene on chromosome 7q11.23 [
5,
6]. SVAS is also reported to occur in association with homozygous (44%) [
7‐
9] or heterozygous (4%) familial hypercholesterolaemia (FH) [
9].