Transposition of the Great Arteries (TGA)

A structurally correct heart carries blood in a specific direction. Oxygen-poor blood from your body enters the right side of your heart and the pulmonary artery directs this blood to your lungs, where the blood becomes oxygenated. Once oxygenated, blood is brought to the left side of your heart and this oxygenated blood is distributed throughout your body via your aorta.

With d-TGA, the pulmonary artery and aorta are switched in position (or transposed), interrupting proper blood flow and resulting in oxygen-poor blood being delivered to the body and oxygen-rich blood stuck circulating between only your lungs and heart.

Most adults with d-TGA have had a surgery to either redirect the blood flow coming to the heart (atrial switch, also known as a “Mustard” or “Senning” procedure), or switch the vessels coming out of the heart (arterial switch). In addition, some patients may have had a ventricular septal defect repair.

After surgery, however, adults with d-TGA are still prone to developing lifelong complications. To avoid this, you will need to be closely monitored by a heart specialist throughout your life.

If you develop complications of d-TGA as an adult, you may experience one or more of the following symptoms:

• Swelling in the face 
• Abdominal distention 
• Shortness of breath 
• Chest pain 
• Palpitations
• Swelling in the legs

The issues and complications that can develop in adults with d-TGA vary depending on the type of surgery used to repair your condition as a child.
Adults with d-TGA should be seen regularly by their cardiologist and at least once per year by an adult congenital heart disease specialist. These experts will use the following noninvasive tests to monitor your condition:

• Chest X-ray
• Electrocardiogram (ECG/EKG)
• Echocardiogram
• Cardiac stress testing
• Cardiac catheterization
• Cardiac MRI
• Cardiac CT
• Pulse oximetry

In some cases, your doctor may prescribe medications to help control your blood pressure, assist your heart in pumping blood more effectively, rid your body of excess fluid, or restore proper rhythm of your heart.

In more severe cases, your doctor may need to perform a catheter-based procedure or even open-heart surgery to repair your heart.

Specifically, some adults with d-TGA may experience symptoms due to narrowing of the repaired segments of the heart and main vessels, or heart failure due to weakening of the main pumping chamber of the heart.

In one more rare variation of d-TGA, return of blood flow to the heart has also been switched during development, and the condition is often called “congenitally corrected” TGA, or L-TGA. As children, those with this condition generally don’t need open-heart surgery. However, adults may need a pacemaker and may be at risk for developing heart failure or valve leakage.