Initially the child will be in congestive heart failure causing the child to be significantly ill because of inability to obtain oxygen properly from the lungs due to the tremendous increase in blood flow to the lungs. In early infancy medications are prescribed to help the baby cope with congestive heart failure. Without medical management the baby may fail to thrive and it may even cause death. However, with proper medications, the baby is typically able to gain weight until it is time to surgically repair the heart at about 6-9 months of age. Failure to do so may result in irreversible damage to the blood vessels of the lungs, which when occur would prevent surgical repair of the heart leading to limitation of life expectancy.
Medical therapy includes medication to help reduce the ill effects of congestive heart failure.
In this view the great vessels are not shown. Initially this will cause less blood flow to the lungs and the patient will actually feel better. Surgical repair within the first year of life is designed to prevent this occurrence. Children with Down's syndrome have a higher tendency to develop such a complication.