Disease Information for Tetralogy of Fallot: Definition

  • A combination of congenital cardiac defects consisting of pulmonary stenosis, interventricular septal defects, dextroposition of the aorta so that it overrides the interventricular septum and receives venous as well as arterial blood, and right ventricular hypertrophy


    Tetralogy of Fallot; Fallot"s Tetralogy;

    Pulmonic Stenosis-Ventricular Septal Defect

    Tetralogy of Fallot is the most common form of cyanotic congenital heart disease; Cyanosis is the abnormal bluish discoloration of the skin that occurs because of low levels of circulating oxygen in the blood; Tetralogy of Fallot consists of the combination of four different heart defects: a ventricular septal defect (VSD); obstructed outflow of blood from the right ventricle to the lungs (pulmonary stenosis); a displaced aorta, which causes blood to flow into the aorta from both the right and left ventricles (dextroposition or overriding aorta); and abnormal enlargement of the right ventricle (right ventricular hypertrophy); The severity of the symptoms is related to the degree of blood flow obstruction from the right ventricle; If infants with tetralogy of Fallot are not treated, the symptoms usually become progressively more severe; Blood flow to the lungs may be further decreased and severe cyanosis may cause life-threatening complications; The exact cause of tetralogy of Fallot is not known-----[NORD website 2005]-----------