Definition
Often accompanied by Williams-Beuren syndrome (mutation of the elastin gene and neighboring genes of the chromosomes 7q11.23; symptoms: elf-like facial features, hypercalcemia, sometimes slight intellectual disability). Thickening of the aortic wall causes supravalvular narrowing, mainly at the level of the sinotubular junction, which can also affect the coronary ostia. Histology: accumulation of collagen and smooth muscle cells leading to rigid artery walls.