ABSTRACT
Key surgical features include the separation of the pulmonary valve from the tricuspid valve in relation to the diameter of the aortic valve, the development of the conal septum, and the attachment of chords to the conal septum, all of which will influence the surgical approach. Coronary artery anatomy is determined and aortic arch abnormalities excluded. When sub-pulmonary stenosis is observed, a cardiac catheter may be useful to visualize the branch pulmonary arteries in tetralogy, and to assess pulmonary artery pressure in transposition. In transposition DORV cyanosis may be profound and a balloon atrial septostomy may be required to improve mixing at an atrial level.
