​Congenitally Corrected Transposition of the Great Arteries​


Congenitally corrected transposition of the great arteries (CCTGA) is a rare disorder in which there is atrioventricular and ventriculoarterial discordance. The term “corrected’ is used as physiology is normal (blue blood reaching pulmonary and red blood to systemic circulation).

The heart contains four chamber; two upper chambers called atria and two lower chambers called ventricles. The oxygen-poor blood enters the right side of the heart from the rest of the body, which is then pumped to the lungs to be oxygenated. The oxygen-rich blood returns to the left side of the heart and from there, pumped to the rest of the body. In CCTGA, morphologic right ventricle is systemic ventricle and morphologic left ventricle is pulmonary ventricle (because of ventricular inversion). This puts strain on the right ventricle.

CCTGA occurs during foetal development, when the heart twists abnormally. Children with CCTGA may also have other associated cardiac defects, like:

  • Ventricular septal defect (VSD): in which a hole is present between the two ventricles

  • Pulmonary stenosis: which is the blockage of the pulmonary artery that transport the blood to the lungs

  • Tricuspid valve abnormalities

  • Complete heart block​

CCTGA can exhibit symptoms in new-borns (if associated with other cardiac defects) while some people may not experience any symptoms until they reach adulthood. Symptoms may include:

  • Fainting,  due to blockage in the electrical conduction

  • Fatigue, as the heart is unable to pump adequate blood to the body​

Seek immediate medical attention if your doctor suspects CCTGA in your baby. Visit Children's Hospital Service Line at The Aga Khan University Hospital the only internationally accredited hospital in Pakistan, for expert consultation.​

Your time with your doctor maybe limited, so make sure to prepare for your visit beforehand. Here are some tips to help get you started.​

The diagnosis begins with a physical exam. The doctor may listen to your child’s heart using a stethoscope to detect heart murmur, an abnormal sound as the blood forces through or near the heart. Some more tests may be recommended which include:

  • Echocardiogram in which sound waves, directed at the heart from a device (transducer) placed on the chest, are used to produce images of the heart. This painless procedure is mostly used to detect CCTGA.

  • ECG (Electrocardiogram) in which the electrical activity of the heart is recorded to detect rhythmic problems

  • Chest X-ray to detect any enlargement of the heart caused by heart or valve disease

  • Cardiac catheterization in which a thin tube (catheter) is inserted in the arm or groin and threaded up to the inside of the heart. This is done to inject a dye in the heart to clearly visualize its structure

  • Cardiac MRI (Magnetic Resonance Imaging) which generates a three-dimensional image of the heart to be studied by the doctor to determine the presence of any abnormalities. This procedure is also mainly used to detect CCTGA​

If your child is diagnosed with CCTGA, they would require complex surgeries by expert doctors who specialize in paediatric cardiology/cardiac surgery, like our highly trained doctors at the Children's Hospital Service Line at The Aga Khan University Hospital. Your child will be given multidisciplinary medical care and treated with utmost care and compassion.

It is also highly possible that your child may not require any treatment if CCTGA it is not accompanied by any other heart defect.

The treatment of your child will depend on his/her age, general health, type and severity of the heart disease. Children with CCTGA may require surgical treatment.

Surgeries include:

  • Treatment of ventricular septal defect for closing the hole and inserting a tube (conduit) between the hearts and lungs

  • Fontan repair in which the blood flow is diverted from the right atrium to the pulmonary arteries without passing through the right ventricle. This means that the deoxygenated blood will flow directly to the lungs for oxygenation, bypassing the heart

  • Double switch operation in which the doctor redirect the blood flow from one side of the heart to the other. The major arteries of the heart are also reversed during this operation. This is a very complex procedure and is usually performed in infants and children

Insertion of pacemaker or replacement of leaky valves may also be done during the above mentioned surgeries.

The Aga Khan University Hospital offers various support services to help with managing or recovering from the disease or condition. These include but are not limited to nutrition, physiotherapy, rehabilitation, specialized clinics and some patient support groups. Your doctor or nurse will advise you accordingly.

The Aga Khan University Hospital offers financial assistance to those who are in need and fulfil the eligibility criteria. For further information, you can contact the Patient Welfare Department. You can find the contact number of the Patient Welfare Department in the 'Important Numbers' section on the website homepage.

The financial counselling staff is available during office hours, at the main PBSD (Patient Business Services Department), to answer your financial queries on treatments' costs and authorize admissions on partial deposit as per hospital policies allow. The financial counsellor in the emergency room is open 24/7. You can find the contact number of the Patient Business Services in the 'Important Numbers' section on the website homepage.

Your doctor and or nurse will give you specific instructions about the prescribed medication. Please ensure that you take or use the prescribed medicine as advised. It can be dangerous to your health if you self-prescribe. Please inform the doctor or nurse beforehand if you have experienced any adverse reactions to any medications in the past. If you experience any symptoms of drug poisoning, overdose or severe reaction please contact the Pharmacy Service at The Aga Khan University Hospital immediately. You can find the contact number of the Pharmacy Services in the 'Important Numbers' section on the website homepage.




The information provided on our website is for educational purposes and not intended to be a substitute for medical advice, diagnosis or treatment. You should always seek the advice of your doctor or other healthcare professional provider.