Anatomic conundrum in a case of complete transposition of the aorta and pulmonary trunk.

An unusual cord-like structure was found on postmortem examination of the heart of a 30-year-old woman who had complete transposition of the great arteries. This extended from the posterior aspect of the right side of the base of the aorta to the posterior wall of the distal part of the arch immediately proximal to the insertion of the arterial ligament. The nature and origin of this is discussed.