[A successful surgical case of supravalvular aortic stenosis with Williams syndrome: the investigations of the procedures].

We experienced a successful surgical case in which a 3-year-old boy with a characteristic elfin face, heart murmur, and mental retardation, underwent extended patch aortoplasty using equine pericardium for congenital supravalvular aortic stenosis. The aortography performed before operation, and demonstrated diffuse stenosis just above the aortic valve, which was a typical hour-glass type. The preoperative peak systolic pressure gradient between the left ventricle and ascending aorta was 120 mmHg, and was improved postoperatively. In this procedure only one cusp was incised, resulting in no deformity of the aortic valve and no obstruction of coronary arteries. In conclusion this method was excellent for the diffuse type of supravalvular aortic stenosis.