The circumference of the aorta is dissected free, and an umbilical tape placed around it, for later use in retraction. Great care is taken not to use the electrocautery around the phrenic nerves. The inferior vena cava and superior vena cava are snared. A temperature probe is placed in the ventricular septum, and myocardial temperature monitored. The right atrium is opened, and the edges retracted with silk.
Note is made of cardioplegia flowing from the coronary sinus.
Myocardial temperature should drop appropriately. The atrial septal defect is closed in standard fashion. The superior vena cava is divided above the area of the sino-atrial node. The disadvantage is that a potentially circular circulation is created, where blood ejected from the right ventricle returns to the right atrium via the pulmonary artery - superior vena cava connection. The pulmonary artery is opened on its superior edge, facing the cephalic end of the divided superior vena cava. .