Great vessels transposition is a serious circulatory disorder occasionally found in newborn babies. The great vessels are the pulmonary artery and vein, the aorta, and the vena cava. In this defect, two of the vessels are exchanged, resulting in deoxygenated blood returning to the body instead of being reoxygenated in the lungs. If this is not corrected before the ductus arteriosus closes, it is fatal.
