Tetralogy of Fallot

What is Tetralogy of Fallots’s (TOF)?

TOF is a cyanotic heart disease that is present at birth, i.e. child born with heart disease.

This consists primarily of a hole known as Ventricular Septal Defect (VSD) and narrowing or obstruction of blood flow to the lungs (Pulmonary Stenosis, PS).

Clinical presentation of TOF?

It depends on severity of PS.

If PS is severe, child is generally blue (cyanosed) and also have an irritable behavior.

If PS is mild with large VSD, child generally have history of poor weight gain, frequent cough and cold, feeding difficulty etc. as it will behave like a large VSD.

Diagnosis of TOF?

For diagnosing TOF, Echocardiography of child needs to be done. Echo is a non-invasive test that is without pain. Echo is done from chest.Generally in small child, echo needs to be done when child sleeps.

Are other Investigation required?
Yes, sometimes we need to do “CT angiography” or “cardiac cath angiography” of heart.
Can we treat TOF by medications?

Medicine is not available for closing VSD and relief of PS. Medicines are used for controlling symptoms due to bluishness, and if child is not operated on time, then medical treatment is advised for increased hemoglobin (polycythemia) if symptomatic.

What are the options for treatment of TOF?

Mainstay of treatment is only by open heart surgery (Intracardiac Repair of TOF).

If child is very blue in early infancy, then surgical options in the form of BT shunt or if suitable then stent can be placed in right ventricular outflow tract angiographically (RVOT stenting) as a palliative procedure. By doing this, child can be less blue for few months. When child grows well, then Intracrdiac repair can be carried out.

Timing of surgery (TOF)?

If child is very blue in early infancy, then as mentioned above BT shunt or RVOT stenting can be advised as an initial treatment.

If child is blue and size of pulmonary arteries (vessels of lung) are small even in more than 5-6 months of age, then again a palliative surgery in the form of BT shunt is advised.

If child is not having any signs of bluishness and growing well with adequate sized branch pulmonary arteries then Intracradiac repair of TOF is done after 5-6 months of age.

Can we delay surgery if child is not having any problems due to TOF?

Ideally, TOF should be operated before child attains one year of age as best outcome will be there in this period.

How we should do follow-up after surgical repair of TOF?

At regular intervals: After 3 days for wound dressing, then 1, 3, 6, 12 months after surgery.