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Congenitally Corrected Transposition of the Great Arteries


Lee B. Beerman

, MD, Children's Hospital of Pittsburgh of the University of Pittsburgh School of Medicine

Reviewed/Revised Apr 2023

In congenitally corrected transposition of the great arteries, the normal connections of the aorta and the pulmonary artery are reversed, but the lower heart chambers (the ventricles) are also reversed, thus "correcting" the circulation so that the oxygen-poor venous blood goes into the lungs and oxygenated blood goes out to the body as it normally should. However, the circulation is not efficient because the right ventricle, which is designed to pump blood to the low pressure circulation through the lungs, is required to pump blood to the much higher pressure circulation to the body.

  • Infants with congenitally corrected transposition of the great arteries have many different symptoms because many additional heart abnormalities occur along with the switched heart chambers.

  • Long-term problems due to weakening of the heart muscle are likely to develop in adulthood due to the right ventricle supplying blood to the body.

  • The diagnosis is based on findings from a doctor's physical examination, electrocardiography (ECG), chest imaging, and cardiac catheterization.

  • Treatment is with medication to control symptoms, surgery to correct the defects, and pacemakers or implantable cardioverter-defibrillators if the abnormality causes an abnormal heart rhythm.


These abnormalities result in a wide range of symptoms. An abnormally slow heart rhythm due to heart block Overview of Heart Block Heart block is a delay in the conduction of electrical current as it passes through the conduction system of the heart, including the atrioventricular node, bundle of His, or both bundle branches... read more may develop. In heart block, the electrical signals that control the heartbeat are partially or completely blocked between the upper and lower chambers of the heart. Heart block is treated with a pacemaker. In addition to the symptoms caused by any of the associated abnormalities, all people with congenitally corrected transposition are likely to develop symptoms secondary to having the circulation to the body supported by the right ventricle.

Infants may have a heart murmur due to pulmonic stenosis or a ventricular septal defect. If stenosis is severe and a ventricular septal defect is present, the skin and lips may appear bluish (cyanosis) because not enough oxygen is reaching the tissues. If a large ventricular septal defect is present, symptoms of heart failure, such as difficulty breathing and poor feeding, may occur. Symptoms may develop gradually during childhood and adolescence depending on the severity of the defects.


  • Stethoscope examination of the heart

  • Electrocardiography (ECG) and chest x-ray

  • Echocardiography (ultrasonography of the heart)

  • Magnetic resonance imaging (MRI) and computed tomography (CT)

  • Cardiac catheterization

Doctors are able to diagnose abnormalities of the heart by listening to the chest with a stethoscope. Doctors might hear a heart murmur or heart sounds might be louder on the right side if the chest than on the left. Subsequently, they usually perform an ECG and imaging studies.


  • Medication

  • Surgery

  • Pacemaker or implantable cardioverter defibrillator

Medication may be needed if heart failure develops.

Surgical treatment is often necessary for ventricular defects or tricuspid regurgitation.

Pacemakers or implantable cardioverter defibrillators may be needed if the congenital transposition causes abnormal heart rhythms.

More Information

The following English-language resources may be useful. Please note that The Manual is not responsible for the content of these resources.

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