Tetralogy of Fallot

From Ganfyd

This condition was first described by Niels Stensen (1638-86), a Danish natural scientist. Fallot (1850-1911) lent his name to it because he first demonstrated that it could be diagnosed in life.

A congenital malformation of the heart, which occurs in roughly 1 out of 2000 infants.

The four parts of the tetralogy are:

• Ventricular septal defect
• Infundibular, valvar or supravalvar pulmonary stenosis / Right Ventricular Outflow tract obstruction
• Over-riding aorta (an anteriorly placed aorta that receives blood from both left and right ventricles)
• Right ventricular hypertrophy

It has been argued that tetralogy is something of a misnomer, as ventricular hypertrophy is merely a consequence of the three actual anatomical malformations, and for this reason, some authors prefer the term "Fallot's syndrome". (And classical grammarians prefer "tetrad" to "tetralogy".) However, many prefer the term tetralogy to distinguish from the rarer Fallot's pentalogy, in which atrial septal defect or patent foramen ovale are also present.

It is corrected surgically by closing the VSD, usually with a Dacron patch, and relieving the RVOT obstruction, by careful resection of tissue, although a transannular patch is sometimes required. This is usually accomplished through a right atriotomy while on cardiopulmonary bypass, and the RVOT is often also opened.