An infant with suspected missed diagnosis of Williams syndrome failed weaning off CPB after surgical correction of pulmonary stenosis: a case report and literature review.

Williams syndrome (WS) is a rare congenital developmental disorder caused by the deletion of between 26 and 28 genes on chromosome 7q11.23. For patients with WS, in view of the particularity of the supravalvular aortic stenosis, choosing appropriate arterial cannula, maintaining higher perfusion pressure as well as strengthening myocardial protection during cardiopulmonary bypass (CPB) is essential to the clinical outcome. Here, we report a child with pulmonary artery valvular stenosis who failed to wean off CPB because of malignant arrhythmias and cardiac insufficiency after surgical correction of pulmonary valvular stenosis. With the assistance of extracorporeal membrane oxygenation (ECMO), emergency cardiac catheterization revealed supravalvular aortic stenosis (SVAS), which suggests a suspected missed diagnosis of WS. Finally, under the support of ECMO, the cardiac function gradually returned to normal, and the child was discharged 23 days after surgery.