Glossary -   Tetralogy of Fallot



Tetralogy of Fallot a condition caused by a combination of four heart defects that are present at birth:

  • Ventricular septal defect or VSD- is a hole in the septum (or wall) between the heart's two lower chambers - the ventricles.
  • Pulmonary stenosis – is when the valve which allows blood to flow from the heart to the lungs –the pulmonary valve - cannot fully open.
  • Right ventricular hypertrophy- is when the muscle of the main pumping chamber on the right side - the right ventricle - is thicker than usual
  • Overriding aorta- the main blood vessel that carries blood away from the heart - the aorta - is an overriding aorta when it is located in the wrong place, specifically when it is between the left and right ventricles, directly over the VSD.