The Congenital Heart Center at C.S. Mott Children’s Hospital is a leader in treatment of corrected transposition of the great arteries. For more information on our programs and services, or to make an appointment, please call 734-764-5176.

Some babies have few symptoms at first. But because the body isn't getting enough oxygen, symptoms may later include fast breathing and a blue tint to the skin, lips, or fingernails.

Prenatal diagnosis: Corrected transposition can be diagnosed before birth by a fetal echocardiogram or heart ultrasound as early as 18 weeks into the pregnancy. This test is done when there is a family history of congenital heart disease or when a question is raised during a routine prenatal ultrasound. Fetal diagnosis of corrected transposition can be difficult unless there is also a VSD, pulmonary stenosis, or heart block.

Symptoms: If the only problem is the reversal in position of the ventricles, there are usually no symptoms until adulthood, and indeed, some people live an entire lifetime without ever knowing they have this "problem."  Most of the time, however, there are other heart problems, too. If there is a large VSD, and not much pulmonary stenosis, symptoms of congestive heart failure occur, usually when a baby is between 6 and 8 weeks of age. If there is a VSD and moderate to severe pulmonary stenosis, the child’s lips and nailbeds may look blue. The medical term for this is cyanosis. If heart block develops possible symptoms include low energy, dizziness, and/or fainting.

Physical findings: Most babies with corrected transposition are born at term and are a normal weight and length. Again, if the only problem is the reversal in position of the ventricles, the examination will be normal. If a VSD, pulmonary stenosis, and/or a leaky tricuspid valve is present, a heart murmur is heard. If there is congestive heart failure, there will be increased heart rate, increased breathing rate, and an enlarged liver. In an older child or adult there may also be swelling of the feet. If there is heart block, the child’s heart rate will be slower than normal.

Medical tests: The diagnosis is confirmed by an echocardiogram. An oxygen saturation test is used to measure the blood oxygen levels. Other tests include an electrocardiogram and chest x-ray.
 

The treatment depends on the presence and severity of other associated heart problems. Congestive heart failure in children is usually first treated with medicines including digoxin and lasix. If these don’t help, and if there is a "fixable" heart defect such as a VSD and/or pulmonary stenosis, a heart operation may be needed. If the pulmonary stenosis is very severe, a conduit may be needed. A conduit is a tube that has a valve inside it. One end of the conduit is sewn into the right ventricle and the other end is sewn into the pulmonary artery. If the tricuspid valve is too leaky, an operation to repair or replace it may be necessary. If the valve is replaced, the child will need to be on blood thinning medicines. If there is heart block causing symptoms of fatigue, dizziness or fainting, a pacemaker is needed.

During adulthood, if congestive heart failure occurs because of longstanding overwork of the misplaced ventricle, the first line of treatment is also heart medicines. If the heart failure progresses so that medicines are no longer effective, a heart transplant may be needed.

In an effort to prevent later problem with congestive heart failure, an operation called the double-switch operation has been utilized. It is most often done during the first six months of life when there is a very leaky tricuspid valve and/or when the right ventricle has poor function right after birth. This operation involves both an arterial switch operation and an atrial switch operation (also called a Mustard or Senning operation). If there is pulmonary stenosis and a ventricular septal defect, a Rastelli and atrial switch operation are done. The goal is to rebuild the heart so that the ventricle on the left side now pumps to the lungs and the ventricle on the right side now pumps to the body. Early and mid-term outcome results suggest that this can be done safely with good result, but it has not been done long enough to know what the long-term results will be.

Exercise guidelines

An individual exercise program is best planned with the doctor so that all factors can be included. In general, there are few restrictions for children with corrected transposition, but this really depends on the presence and severity of other heart defects. If a pacemaker or valve replacement is needed, the child will usually be restricted from vigorous or competitive sports but can participate in non-contact recreational sports. The doctor may recommend that the child be able to self-limit their activity, which means that they should be allowed to rest whenever they feel the need to do so.