Transposition of the Great Arteries
One of the most common complex congenital heart defects, Transposition of the Great Arteries (TGA), occurs when the two main vessels of the heart are switched in position during development of the baby. At birth, the blue, oxygen-poor, blood returning to the right ventricle is pumped out of the vessel called the aorta to the body instead of the lungs, and the red, oxygen-rich, blood is pumped by the left ventricle back to the lungs through the pulmonary artery instead of the body. As a result, these babies often need early catheterization and heart surgery.
Most adults with 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.
In one more rare variation of TGA, return of blood flow to the heart has also been switched during development, so the condition is often called “congenitally corrected” TGA, or L-TGA. As children, these patients generally do not need open-heart surgery, however, as adults they may need a pacemaker and may be at risk for developing heart failure.
Symptoms of TGA
- Swelling in the face
- Abdominal distention
- Shortness of breath
- Chest pain
- Swelling in the legs
Expected issues in adults with TGA are dependent on the type of surgery the patient underwent during childhood. Evaluation may require one or more of the following tests:
- Chest X-ray
- Electrocardiogram (EKG)
- Treadmill stress test
- Cardiac catheterization
- Cardiac magnetic resonance imaging (MRI)
- Pulse oximetry
Specifically, some adults with 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. Adults with TGA should be seen regularly by their cardiologist and at least once a year by an adult congenital heart specialist at a center like Houston Methodist.