Surgical treatment of patent ductus arteriosus: a new historical perspective.

The conventional surgical history of ligation of a patent ductus arteriosus (PDA) dates from August 26, 1938, when Robert E. Gross of Boston, Massachusetts, successfully ligated a PDA. It is largely unknown that in the same year and before Gross, Emil Karl Frey, a Surgeon at the Medizinische Akademie in Dusseldorf, Germany, already ligated a PDA successfully. Assuming that he would soon perform more ligations, Frey did not publish his findings, and this historic ductal operation escaped attention.