The Blalock Taussig anastomosis is accomplished as Palliativoperation in the case of certain cyanotic heart errors. A branch of the Arteria subclavia (or Arteria carotid) is separated and connected with the Arteria pulmonalis (lung artery). Thus the lung increases oxygen-poor blood from the body cycle supplied. Cyanosis moderated to a correction operation to be accomplished can. A classical application reason is the Fallot' Tetralogie. Separating the Arteria subclavia has usually no negative effects on the growth of the left arm. The first operation took place on 29 November 1944.