The treatment of transposition of the great arteries (TGA) involves repair of the defect(s) as quickly as possible, coupled with preventive steps to keep the baby alive until surgery. To keep the ductus arteriosus open (which helps by mixing oxygen-rich and oxygen-poor blood) physicians may give the baby infusions of a drug called prostaglandin.

A physician may also perform a procedure called a balloon atrial septostomy. During this catheter-based procedure, a balloon-tipped catheter is guided into one of the atria (upper chambers of the heart) where it is used to either expand or create a hole in the wall of muscle separating the atria (septum). This aids in the mixture of oxygen-rich and oxygen-poor blood. It is a palliative procedure, or temporary procedure designed only to relieve the worst of the defect until corrective surgery can be performed.

Another such palliative procedure is known as pulmonary artery banding. During this procedure, a band is placed around the pulmonary artery to reduce the pressure of blood flowing to and from the lungs. This reduces the likelihood of high blood pressure developing in the lungs (pulmonary hypertension), which can cause permanent damage to the blood vessels of the lungs. Palliative techniques such as these improve the baby’s condition by alleviating some of the heart’s workload and helping to prevent heart failure. However, corrective surgery is necessary to correct TGA as soon as possible.

To correct TGA, the surgeon will perform an arterial switch operation. During this procedure, the aorta and pulmonary artery are returned to their normal positions. The end of the pulmonary artery is carefully cut from the left ventricle (lower chamber of the heart) and sewn to the right ventricle, and the end of the aorta is carefully cut from the right ventricle and sewn to the left ventricle. At the same time, any associated defects, such as ventricular septal defects, are repaired. Also, the surgeon will repair or move any defects in the coronary arteries, which should normally connect to the aorta and supply the heart itself with oxygen-rich blood. There is a range of coronary artery abnormalities associated with TGA.

After surgery and recovery, lifelong medical management will be necessary. Additional surgeries may be necessary, such as to repair valves or improve the heart’s pumping ability.  Also, the patient may need to take antibiotics before dental procedures or other surgeries to prevent infection of the heart walls or valves (bacterial endocarditis).

According to the American Heart Association, people with TGA can expect:

• Probable restrictions on physical activity, as recommended by their cardiologist (e.g., no competitive sports)
  
  
• An increased risk of developing abnormal heartbeat (arrhythmias), which may require periodic monitoring with cardiac catheterization
  
  
• An increased risk to female TGA patients during pregnancy if there are serious problems with heart muscle or arrhythmias, though women with repaired TGA can have successful pregnancies

Research has shown that many adults with congenital heart defects such as TGA do not receive regular cardiac care. The U.S. National Institutes of Health (NIH) is considering requests from cardiologists to establish a national registry of such patients to improve care.