Introduction
Tetralogy of Fallot is a congenital heart condition made up of four problems: a hole between the lower chambers (VSD), a narrowing below or at the pulmonary valve, a thickened right ventricle and an aorta that sits over the hole.
These problems reduce the amount of blood that reaches the lungs, so the body may not receive enough oxygen, and the child may look blue. Surgical repair closes the hole and widens the outflow to the lungs.
Why the procedure is needed
Without treatment, children with TOF may have:
- A bluish colour of the lips, skin or nails (cyanosis), especially when crying or active
- Sudden "spells" of deep blueness, rapid breathing and irritability
- Poor feeding, slow weight gain and tiredness
- Squatting or stopping play to rest in older children
- Reduced oxygen supply to the body and, over the years, complications of the heart and other organs
Who may benefit
- Infants and children diagnosed with Tetralogy of Fallot, usually repaired in the first year or two of life, depending on the child
- Children with spells or marked cyanosis, who may need earlier treatment
- Some children need a temporary shunt operation first to improve blood flow to the lungs, with full repair later
- Adolescents and adults who were not repaired in childhood, or who need further surgery after an earlier repair
What the repair does
- Closing the VSD
- A patch closes the hole between the lower chambers, so the oxygen-poor and oxygen-rich blood no longer mix.
- Opening the outflow to the lungs
- The narrowed area below or at the pulmonary valve is widened by removing thickened muscle, and sometimes by placing a patch.
- Pulmonary valve
- If the valve is also narrow, it may be widened or opened, and in some cases a patch across the valve leaves it leaking, which may need treatment later.
- Timing
- Most children are repaired in infancy. Some need a first temporary operation (a shunt) before complete repair.
- Lifelong follow-up
- Children and adults need regular follow-up with a paediatric or congenital heart specialist, because later procedures, such as pulmonary valve replacement, may be needed.
Procedure overview
Step 1: Assessment
Echocardiography and, where needed, CT, MRI or cardiac catheterisation show the heart and the lung vessels. A paediatric cardiologist and surgeon plan the timing.
Step 2: Anaesthesia
General anaesthesia is given by a specialist team experienced with babies and children.
Step 3: Surgical access
The heart is reached through the breastbone. The heart-lung machine takes over circulation.
Step 4: Repair
The VSD is closed with a patch, and the narrowing below or at the pulmonary valve is relieved. The surgeon may enlarge the outflow with a patch.
Step 5: Checking the repair
After the heart restarts, the repair is checked, often with echo, before closing the chest.
Step 6: Intensive care and recovery
The child is closely watched in intensive care, then on the ward. Follow-up echocardiograms and regular check-ups continue for life.
Clinical advantages
- Corrects the main problems and improves the oxygen level in the blood
- Relieves blue spells and allows better growth and activity
- Most children can lead an active life after repair, with regular follow-up
- Early repair protects the heart and other organs from long-term effects of low oxygen
Risks and considerations
Every operation carries risk. The points below are general; your own risk depends on your health and on the operation you need.
- General risks of open-heart surgery in children: bleeding, infection and rhythm problems
- Heart block or other rhythm problems that may need a pacemaker
- Leakage of the pulmonary valve over time, which may need valve replacement later
- A small leftover hole or a narrowing that needs more treatment
- Risk depends on the child's weight, anatomy, other conditions and the centre's experience with congenital surgery
Frequently asked questions
At what age is TOF repaired?
Often in the first year of life, but the timing depends on the child's anatomy and symptoms. Your paediatric cardiologist and surgeon will advise.
Will my child need more operations later?
Some children need further procedures in later life, such as pulmonary valve replacement. Regular follow-up is how this is decided.
Can my child play and exercise normally?
Many children do, but advice varies by child. Your specialist will tell you which activities are suitable.
What are "blue spells"?
Sudden episodes where the child becomes very blue, breathes fast and is irritable. They need urgent medical attention, and often mean surgery should not be delayed.
What follow-up is needed?
Regular visits to a paediatric or adult congenital heart specialist, with echocardiograms and other tests as advised, throughout life.
Patient-friendly summary
TOF repair corrects four related heart defects so that blood reaches the lungs and the body gets enough oxygen. Most children do well and lead active lives, but need lifelong follow-up and sometimes more procedures later. Treatment decisions belong with a paediatric cardiologist and a congenital heart surgeon.