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​

When to seek expert advice

Seek immediate medical attention if your doctor suspects CCTGA in your baby. Visit the Department of Paediatrics at The Aga Khan University Hospital the only internationally accredited hospital in Pakistan, for expert consultation.