5. Tetralogy of Fallot

Question 1

Classical picture?

Answer 1

The classical picture of tetralogy of Fallot
represents the simultaneous presence of
major and basic changes which are: pulmonary
stenosis, ventricular septal defect,
transposition of the aorta, and a right
ventricular hypertrophy.

Question 2

Division?

Answer 2

The pulmonary stenosis can be valvular or
infundibular type. The dextroposition of the
aorta can be partial or complete. The
increasing right ventricular pressure during
systole leads to right ventricular hypertrophy.

Question 3

Pulmonary stenosis?

Answer 3

The pulmonary
stenosis can occur together with stenosis of
the pulmonary artery branches. The blood
flows to the pulmonary vasculature instead of
flowing to the aorta.

Question 4

The right to left shunt?

Answer 4

The right to left shunt is
the cause of hypoxemia and cyanosis, finger clubbing, and polyglobulinemia. Cyanosis doesn’t
manifest itself from the very beginning of this anomaly. If cyanosis doesn’t occur shortly after birth, it
usually appears before the first year of life. The explanation of this phenomena is that ductus
arteriosus remains patent for few months after birth (its closure is opposed by the pressure
gradient).

Question 5

Limiting factors?

Answer 5

The limiting factors of the proper hemodynamics are the pulmonary stenosis in the first
place and the size of ventricular septal defect in the second place.