Transposition of the great arteries (TGA) occurs when the two main arteries are blood vessels leaving the heart or reversed and there is a hole in the wall between the right and left ventricle called a ventricular septal defect (VSD). The pulmonary artery arises from the left ventricle (instead of the right), sending oxygen-rich blood back to the lungs. The aorta arises from the right ventricle (instead of the left), sending oxygen-poor blood back to the body. This misrouting stops oxygen from being delivered to the body’s tissues and organs and can be life-threatening. The VSD can allow the for the deoxygenated and oxygenated blood to mix. Babies can look blue, especially around the lips and nails. They can have a fast heart rate, fast breathing, and poor feeding.