Transposition Of Great Arteries

Dr. Ira Shah
Consultant Pediatrician, B.J.Wadia Hospital for Children, Mumbai, India
First Created: 01/09/2001  Last Updated: 08/01/2015

Patient Education

What is Transposition of the Great Arteries (TGA)?

The heart pumps the blood in the two arteries - the aorta which supplies the pure blood to the body and the pulmonary artery that supplies impure blood to the lungs. Normally the pulmonary artery arises from the right ventricle (right side of the heart) and the aorta arises from the left ventricle (left side of the heart). In TGA, the aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle. Thus, in TGA, impure blood that returns to the right ventricle instead of going to the lungs passes into the aorta and back to the body. Also, pure blood that comes from the lungs in the left ventricle goes back to the lungs through the pulmonary artery. As a result, every organ of the body receives less oxygen and the patient looks "blue" due to less oxygenated blood.

How does a child with TGA survive?

Since in TGA, 2 parallel circulations are created- one that carries the pureblood and one in which impure blood is carried, life would not be possible. Hence nature creates a way in which" MIXING" of both circulations can occur. This could be by way of another heart defect such as ASD - Atrial septal defect (mixing occurs at the level of the atria), VSD- Ventricular Septal defect (mixing occurs at the level of the ventricles) or PDA- Patent Ductus Arteriosus (mixing occurs by a channel between the aorta and the pulmonary artery).

PDA normally closes within hours after birth (DUCT DEPENDENT CIRCULATION) but a drug called Prostaglandin can keep it open for a few hours to days till surgery is performed.

How is TGA detected?

Any baby with bluish discoloration, breathlessness, and heart failure is suspected to have TGA, which is diagnosed on echocardiography (ultrasound of the heart).

What happens if TGA is left untreated?

If TGA is left untreated, 90% of the patients do not survive more than 1 year of age.

When should a TGA be treated?

Most cases of TGA need to be treated “ AT BIRTH ” especially those with DUCT DEPENDENT CIRCULATION.

In patients with TGA and VSD, enough mixing of blood takes place for the child to survive. However, the child will have fatigue, giddiness, fainting spells, repeated chest infections, breathlessness, and long-duration- irreversible thickening of blood vessels in the lungs.

Also, patients with TGA with VSD with narrowing of the pulmonary valve (Pulmonary valve regulates the outflow of blood from the right ventricle) survive up to their 20’s and 30’s as hypertension in the blood vessels in the lungs develop late.

The type of operation depends on the associated heart defects, the age of the child, and the cost of surgery.

Transposition of Great Arteries Transposition of Great Arteries 2015-08-01
Disclaimer: The information given by is provided by medical and paramedical & Health providers voluntarily for display & is meant only for informational purpose. The site does not guarantee the accuracy or authenticity of the information. Use of any information is solely at the user's own risk. The appearance of advertisement or product information in the various section in the website does not constitute an endorsement or approval by Pediatric Oncall of the quality or value of the said product or of claims made by its manufacturer.
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0