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Tetralogy of Fallot

Other Names for this Disease
  • Fallot tetralogy
  • TOF
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Tetralogy of Fallot is a complex congenital heart defect characterized by a large ventricular septal defect (hole between the right and left ventricles), pulmonary stenosis (narrowing of the valve and artery that connect the heart with the lungs), an overriding aorta (the aorta - the artery that carries oxygen-rich blood to the body - is shifted over the right ventricle and ventricular septal defect, instead of coming out only from the left ventricle), and right ventricular hypertrophy (the muscle of the right ventricle is thicker than usual). Tetralogy of Fallot causes low oxygen levels in the blood, which can lead to cyanosis (a bluish-purple color to the skin). The cause of this condition is unknown. Treatment involves surgery to repair the heart defects. Sometimes more than one surgery is needed.[1][2] 
Last updated: 3/15/2012


  1. Schumacher KR. Tetralogy of Fallot. MedlinePlus. 2011; Accessed 3/15/2012.
  2. What Is Tetralogy of Fallot?. National Heart, Lung & Blood Institute (NHLBI). 2011; Accessed 3/15/2012.
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Basic Information

  • MedlinePlus was designed by the National Library of Medicine to help you research your health questions, and it provides more information about this topic.
  • The National Organization for Rare Disorders (NORD) is a federation of more than 130 nonprofit voluntary health organizations serving people with rare disorders. Click on the link to view information on this topic.

In Depth Information

  • Medscape Reference provides information on this topic. Click on the link to view this information. You may need to register to view the medical textbook, but registration is free.
  • The Online Mendelian Inheritance in Man (OMIM) is an catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs.  Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Tetralogy of Fallot. Click on the link to view a sample search on this topic.