Transposition of the great arteries (TGA) factsheet


Transposition of the great arteries (TGA) is a type of heart defect that your baby is born with (congenital). In this condition, the two arteries that carry blood from the heart to the lungs and body are not connected as they should be. They are reversed (transposed). 

This means that:

  • oxygen-poor (blue) blood is sent to the body instead of to the lungs
  • oxygen-rich (red) blood returns to the lungs instead of going to the body.

Babies can't live with this condition unless they get treatment.

 Signs and symptoms

Most babies with TGA have blue skin color (cyanosis) in the first hours or days of their lives.  

Other symptoms that can occur include:

  • fast breathing
  • trouble breathing
  • fast heart rate
  • poor feeding

The symptoms of TGA may be like symptoms of other conditions. Your doctor will perform tests to determine the correct diagnosis. 


If your child has signs of TGA after birth, a paediatric cardiologist or neonatologist will assess your baby. 

A paediatric cardiologist is a doctor with special training in treating heart problems in babies and children. A neonatologist is a doctor with special training in treating problems in newborns. These doctors will be part of your baby’s heart care team.

Your child’s doctor may do tests to confirm the diagnosis. The tests your child has depends on their age and condition. 

Pulse oximetry - A probe is placed on your child's finger or toe to measure the level of oxygen in the blood, if it is below a certain level, this may be a sign of TGA

Chest X-ray - A chest X-ray shows the size and shape of the heart and lungs

Electrocardiogram (ECG) - This test records the electrical activity of the heart. It also shows abnormal rhythms and spots heart muscle stress.

Echocardiogram (echo) - An echo uses sound waves to take a moving picture of the heart and heart valves. This test may show TGA.

Cardiac catheterisation – Small thin tube is injected in your child’s groin and guided to their heart. This test gives detailed information about the structures inside the heart. Your child will be given medications to help relax.   


All children with a TGA require surgery. Your baby will likely be admitted to the intensive care unit (ICU).

Medical management

At first, your baby may get the following care:

  • Supplemental oxygen or a ventilator. This is a machine that helps do the work of breathing for the baby.  
  • Different types of medicine given by an intravenous cannula (IV). This will help your baby’s heart and lungs work better. 

Cardiac catheterisation

Your child may have a test called a balloon atrial septostomy. This is done during cardiac catheterization. This test makes it easier for oxygen-rich blood to reach the rest of the body.  


Typically, in the first few weeks of life, your baby will need surgery for TGA. This procedure is called an arterial switch. Your child’s surgeon will connect the aorta and pulmonary artery to their normal ventricles. The surgeon will move the coronary arteries. The surgeon will also fix any other heart problems.   


Care after surgery

 Your child’s healthcare team will tell you how to care for your baby before you leave the hospital. He or she may also give you information about home healthcare for your baby if you need it.  

Your child will still need to see his or her heart doctor for checkups. Your child may need additional surgeries or cardiac catheterisations in the future.  

Your child's doctor may give him or her antibiotics before surgeries or dental procedures. This is to prevent infections. Your child may also need to limit physical activity and avoid certain sports. Ask your child’s heart doctor what activities are safe for your child. 

Dextro-Transposition of great arteries

D-TGA or Dextro-Transposition of great arteries, is another name for TGA.  It is when the positions of the aorta (carries oxygenated blood to the body) and pulmonary artery (carries deoxygenated blood to the lungs) are switched, causing a shortage of oxygen-rich blood in the body.  

D-TGA requires surgery like TGA. 

Last updated Monday 29th January 2024


This factsheet is provided for general information only. It does not constitute health advice and should not be used to diagnose or treat any health condition.

Please consult with your doctor or other health professional to make sure this information is right for you and/or your child.

The Sydney Children’s Hospitals Network does not accept responsibility for inaccuracies or omissions, the interpretation of the information, or for success or appropriateness of any treatment described in the factsheet.

© Sydney Children’s Hospitals Network 2024