CASE REPORTS of severe abdominal pain following resections of coarctation of the aorta began to appear in 1951,1 some six years after Crafoord and Nylin2 and Gross and Hufnagel3 simultaneously initiated the surgical correction of this congenital lesion. In 1953, Sealy4 reported the performance of a laparotomy for an abdominal complication which occurred on the sixth day after resection of the coarcted segment. At surgery, the jejunum and first portion of the ileum were edematous and cyanotic. The patient died during the exploration, and at autopsy there was inflammation of the small arteries and arterioles confined to the body area below the coarctation. Ring and Lewis5 first applied the term "syndrome" to these ever-increasing abdominal complications. There has evolved a well-defined clinical entity which consists of abdominal pain, distention, fever, leukocytosis, and melena occurring on or about the fourth postoperative day, predominantly in males who