What is Tetralogy of Fallot (TOF)?

Also known as: tetralogy, TOF

Tetralogy of Fallot (TOF) is a heart condition of several (“tetralogy” refers to four) defects present at birth that occur due to abnormal development of the heart during pregnancy. TOF is one of the most common congenital heart defects.

  • Ventricular Septal Defect (VSD): An opening in the wall that divides the two lower chambers of the heart known as the right and left ventricles.
  • Overriding aorta: The aorta is moved to right side of the heart so that it sits over the ventricular septal defect.
  • Pulmonary obstruction: A muscular obstruction in the right ventricle that lowers normal blood flow.
  • Right ventricular hypertrophy: The right ventricle becomes thickened as it tries to pump blood past the obstruction

This page was last updated on: 1/29/2019 3:21:13 PM

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