Acquired von Willebrand Syndrome in an Infant With Coarctation of the Aorta and Williams Syndrome.

An infant with coarctation of the aorta and Williams syndrome was noted to have petechiae in cardiology clinic prior to planned surgical intervention. Workup revealed acquired von Willebrand syndrome secondary to the high shear force generated by the aortic coarctation. He was treated with intra- and postoperative Humate P; there were no postoperative bleeding complications. His acquired von Willebrand syndrome resolved postoperatively.