Normally, the aorta leaves the left ventricle carrying oxygen-rich (red) blood to the body, and the pulmonary artery leaves the right ventricle carrying oxygen-poor (blue) blood to the lungs to get oxygen. The reversal in TGA changes the way blood circulates through the body, causing a shortage of oxygen in the blood leaving the heart going to the rest of the body.
According to the National Heart, Lung, and Blood Institute (NHLBI), TGA affects roughly 5 out of every 10,000 babies. The defect is found more frequently in Caucasians. Untreated, more than 50% of infants with transposition will die in the first month of life, 90 % in the first year.
TGA usually is diagnosed based on the above signs and symptoms, a physical exam, and the results from tests and procedures.
During a physical exam, your doctor will listen to your baby’s heart and lungs to check for a murmur and will evaluate your baby’s general appearance to look for signs of a heart defect, such as a bluish tint to the skin, lips, or fingernails and rapid breathing.
TGA is one of the critical congenital heart defects that can be detected on pulse oximetry. Pulse oximetry is a simple, non-invasive, bedside test to determine the amount of oxygen in the baby’s blood.
If your doctor finds any signs of TGA, your baby likely will undergo additional testing. Additional tests that your doctor may order include a chest x-ray, echocardiogram (echo), electrocardiogram (EKG), or cardiac catheterization. For more information on these tests, visit our common diagnostic tests page.
The only treatment for TGA is open heart surgery, which is performed by a pediatric/congenital heart surgeon (cardiothoracic surgeon).
Be sure to speak with your baby’s doctor about what you should expect during and after the surgery. You can print these sample questions to use as a basis for discussion with the doctor.
Expected outcomes: The Society of Thoracic Surgeons (STS) Congenital Heart Surgery Database shows an expected outcome of 1.9% mortality for arterial switch operation for isolated transposition of the great arteries. Mortality is higher when there are additional defects like a hole in the heart (VSD) or narrowing of the arteries to the body (aorta). Outcomes will vary across different programs. It is appropriate to inquire about the outcomes of a surgical group or surgeon during your consultation.
Expected hospital stay after the arterial switch operation is approximately 2 weeks. This can vary depending on how sick the baby is prior to surgery, time to full feeds postoperatively, and any other issues that may delay discharge.
After surgery, your baby will require continued follow-up care. The doctor will schedule routine checkups to make sure that the procedure was successful and monitor for any new problems. Most children with successful complete repair will not have any activity restrictions as they grow older.
Most children who undergo the arterial switch operation do not need any additional surgery, but sometimes patients who had an operation to repair TGA in infancy need additional surgery as they age.
Most often, this procedure is undertaken to repair or replace leaky heart valves, open up areas of narrowing, abnormal heart rhythm, and address problems with the arteries that supply the heart with blood (coronary arteries).
Illustration by Steven P. Goldberg, MD
Preventive antibiotics are almost always recommended for people who have artificial valves or who’ve had repair with prosthetic material. Be sure to ask your doctor about what is right for your child.
Reviewed by: Lauren C. Kane, MD
December 2017
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