Tétralogie de Fallot

The Tetralogy of Fallot refers to the most common cyanotic congenital heart defect. Anatomically, this is essentially a perimembranous subaortic ventricular septal defect, together with a right ventricular outflow obstruction, resulting from an infundibular and often valvular pulmonary stenosis. The pathophysiology is a right to left shunt at ventricular level. Clinical signs include cyanosis, which is often progressive with age, squatting, and often hypoxic spells. The natural history is characterized by progressive cyanosis, erythrocytosis, and complications such as cerebrovascular accidents and brain abscesses. Death occurs in the second decade as a mean. Surgical correction is therefore mandatory and lifesaving. The operation includes closure of the ventricular septal defect with a patch, and relief of pulmonary infundibular and valvular stenosis. This may often require patch enlargement of the right ventricular outflow tract, including the pulmonary valve annulus, leaving the pulmonary orifice partially unguarded. As a consequence, pulmonary valve regurgitation is very often observed. If it is important, it may compromise right ventricular function in the long term. Rhythm disturbances are another common complication in the late follow-up of operated tetralogy of Fallot. For these reasons, medical follow-up is indicated. Despite these possible complications, it is obvious that longevity and quality of life have been considerably improved by surgical repair.