Which finding is NOT consistent with Tetralogy of Fallot?

Which finding is NOT consistent with Tetralogy of Fallot?

• A. Boot-shaped heart
• B. Right-to-left shunt
• C. Cyanosis at birth
• D. Egg-shaped heart

Answer: (D)

In Tetralogy of Fallot the key features are pulmonary stenosis, right ventricular hypertrophy, an overriding aorta, and a ventricular septal defect. The chest X-ray classically shows a boot-shaped heart because the right ventricle enlarges and pulls the apex up and left, reflecting the subpulmonic obstruction. The reduced pulmonary blood flow from the stenosis promotes a right-to-left shunt across the VSD, which explains why cyanosis can be present at birth or early in life. An egg-shaped heart is not a typical finding in TOF; that radiographic appearance is more associated with transposition of the great arteries. So the finding that is not consistent with Tetralogy of Fallot is the egg-shaped heart.

In Tetralogy of Fallot the key features are pulmonary stenosis, right ventricular hypertrophy, an overriding aorta, and a ventricular septal defect. The chest X-ray classically shows a boot-shaped heart because the right ventricle enlarges and pulls the apex up and left, reflecting the subpulmonic obstruction. The reduced pulmonary blood flow from the stenosis promotes a right-to-left shunt across the VSD, which explains why cyanosis can be present at birth or early in life. An egg-shaped heart is not a typical finding in TOF; that radiographic appearance is more associated with transposition of the great arteries. So the finding that is not consistent with Tetralogy of Fallot is the egg-shaped heart.