[Williams syndrome. Considerations on an unusual case].

We report one case of WS, who came at our first observation at age of eight for mental retardation and congenial cardiopathy of unknown origin. Echocardiography and Doppler examination showed immediately isthmic aortic stenosis, and therefore aortic plastic surgery was performed, with a good post-operative result. The case aroused the interest of the Authors, owing to the late diagnosis of aortic coarctation, which, however, did not produce hemodynamic alteration.