Munson Health
Tetralogy of Fallot

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by Rosenblum L




Tetralogy of Fallot (TOF) is a combination of four heart defects. It is present at birth. These defects make it difficult for your child to get oxygen to the entire body.
The four defects are:
  • Ventricular septal defect (VSD) —A hole in the heart. It is on a wall that separates the two lower chambers.
  • Overriding aorta—The aorta, which is the body's largest artery, comes out of the left ventricle, but partially covers or comes out of the right ventricle
  • Pulmonary stenosis—The valve in the heart that allows blood to pass from the heart toward the lungs is too narrow.
  • Right ventricular hypertrophy—The muscle on the right side of the heart is too thick.
VSD and overriding aorta can decrease the amount of oxygen in the blood. This makes it difficult for the body to get the oxygen it needs. Pulmonary stenosis and right ventricular hypertrophy can make it difficult for blood to pass to the lungs. This will also decrease the amount of oxygen in the blood.


American Heart Association

National Heart, Lung, and Blood Institute



About Kids Health

Canadian Adult Congenital Heart Network



Tetralogy of fallot. American Heart Association website. Available at: Updated March 30, 2012. Accessed May 20, 2013.

Tetralogy of fallot. Cincinnati Children's Hospital website. Available at: Updated October 2012. Accessed May 20, 2013.

Tetralogy of fallot in infants and children. EBSCO DynaMed website. Available at: Updated December 20, 2012. Accessed May 20, 2013.

What is tetralogy of fallot? National Heart, Lung, and Blood Institute website. Available at: Accessed May 20, 2013.

10/1/2013 DynaMed's Systematic Literature Surveillance Molgaard-Nielsen D, Pasternak B, Hviid A. Use of oral fluconazole during pregnancy and the risk of birth defects. N Engl J Med. 2013 Aug 29;369(9):830-9.


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