transposition of the great arteries

Last edited 02/2023 and last reviewed 03/2023

Transposition of the great arteries is diagnosed when the the aorta is connected to the anatomic right ventricle and the pulmonary artery is connected to the anatomic left ventricle.

In TGA the pulmonary and systemic circulations function in parallel rather than in series. The neonate will only survive if there is mixing of the two circulations, ie persistence of the ductus arteriosus and/or the foramen ovale.

  • accounts for 3% of all congenital heart disease and 20 % of cyanotic heart disease (1)
  • incidence is estimated at is 4.7 per 10,000 live births (1)