This is a model of a patient with an unbalanced atrioventricular septal defect (AVSD) with a hypoplastic left ventricle who underwent a Fontan procedure as the final stage of the surgical palliation. This is a myocardial model, meaning that you are seeing the muscle of the heart rather than the blood inside the heart. This model has been coloured to demonstrate the presumed oxygen saturations within the different chambers and blood vessels of the heart. In this model, there is no Fontan fenestration present.