Reviewing our experience of scoliosis in children with a Cavopulmonary Shunt or Fontan circulation and the cardiovascular challenges that this presents. A notes and x ray review was performed. Special attention was paid to the changes in cardiovascular status whilst prone. The review was from first presentation to latest follow up. There were 6 patients who underwent 7 major procedures between 2001 and 2009. All had cardiac procedures in early life. Both definitive fusion and growing instrumentation was used. All procedures were successful. Growing instrumentation allowed earlier primary surgery before completion of the Fontan circulation. All have been subsequently lengthened in a lateral position. The mean follow up is 56 months. There was one death 40 months following last surgery, cause unrelated to spinal surgery. In the older patients with a completed Fontan significant blood loss was seen, due to the raised venous pressure required to run the Fontan, and occult hypotension seen as a climbing difference between Pulmonary Artery Wedge Pressure and Central Venous Pressure were common when prone. We recommend early intervention, using instrumentation without fusion to correct the deformity over time and allow intervention prior to completing the Fontan circulation. As haemodynamic instability increases with increasing time in the prone position, surgery should be expedited rapidly