Fallot's tetralogy

A congenital condition characterized by:

1. Stenosis of the outflow tract of the right ventricle (infundibulum).
2. Defect in the interventricular septum.
3. Dextroposition of the aorta.
4. Hypertrophy of the right ventricle.

It forms about 10 % of congenital heart disease. Both sexes affected; slight male prevalence. Detected weeks or months after birth. Clinical features are cyanosis from birth or developing in the first year of life caused by the lung's inability to oxygenate sufficient blood for the system, difficulty in feeding, failure to gain weight, retarded growth and physical development, dyspnoea on exertion, clubbing of the fingers and toes, and polycythaemia. Many cases can be operated successfully. There may be permanent cyanosis. Also found in cattle and dog.

Some writers prefer the term «Fallot’s syndrome», saying that that the term «Fallot’s tetralogy» is a misnomer inasmuch as hypertrophy of the right ventricle, which comprises the fourth characteristic of the tetralogy, is simply the functional consequence of the triad of congenital malformations.

The Blalock-Taussig operation corrects this condition surgically.

The deformation of the heart known as the tetralogy of Fallot was first described in 1671 by the Danish physician, natural scientist, bishop – and later Saint –Niels Stensen (Nicolaus Stenonius). At least some forty case descriptions precluded that of Fallot. His delineation from 1888 was based on details of the pathological features of two persons with the condition, together with a survey of some 50 previous observations.

Fallot considered the deformity as an entity and as such the most common cause of cardiac cyanosis. By his contemporaries Fallot's observations were considered to be solely of theoretical or curious interest. Congenital heart malformations attracted little attention, as there was still no therapy available. Fallot's work first received serious attention when Paul Dudley White (1886-1973) in 1931 discussed the malformation and translated Fallot's works.

We thank Martin Lehn, Germany, for information submitted.

• N. Stensen:
  Embryo monsto affinis Parisiis dissectur.
  Acta Medica & Philosophica Hafniensia, 1671-72, 1: 202-203.
• E. L. A. Fallot:
  Contribution à l’anatomie pathologique de la maladie bleue (cyanose cardiaque).
  Marseille médical, 1888, 25: 77-93, 138-158, 207-223, 341-354, 370-386, 403-420.