The two important features of Tetralogy of Fallot are narrowed artery and Ventricular Septal Defect (VSD) (hole in heart).
The narrower the artery, the easier blood returning from the body can pass through the VSD and straight into the body artery (Ao) without going through the lungs.
Patients with this condition do not have enough oxygen in their blood and are therefore blue. The degree of blueness depends upon the narrowing. If mild, the blueness may be hardly noticeable.
They also have a heart murmur as the blood makes a sound as it passes through the narrowing.
In the most severe form of the condition, the valve is not narrowed but completely blocked. This is called Pulmonary Atresia - VSD.
Their skin appears bluish. The degree of blue colouration depends upon the narrowing. If mild, the blueness may be hardly noticeable.
Blue colouration is common in babies and young children. It is usually confined to the area around the mouth ("muzzle area"), the hands and feet. The colour change usually occurs for no apparent reason despite the child being completely well. The technical term for these colour changes is acrocyanosis which is probably caused by local variation in blood flow through the skin - as oxygen is extracted from the blood by the tissues it changes to a blue colour. It is of no consequence and usually goes away as the child gets older.
Blue colour (cyanosis) can be a sign of heart disease - it occurs in some conditions babies are born with, in this case, Tetralogy of Fallot.
In children over 6 months of age, mild swelling of the ends of the fingers can be seen. This is known as clubbing. This goes away when the cause is treated. Sudden changes of colour can occur in Tetralogy of Fallot and should be taken very seriously.
The blue colouration may occur in other conditions including breathing problems when it becomes a state of medical emergency.
These children also have a heart murmur as the blood makes a sound as it passes through the narrowing.
People with DiGeorge Syndrome are usually rather small and may be slow developers. They may have a speech impediment and feeding difficulties. Some also have an immune deficiency and infections, vaccinations and blood transfusions can cause problems.
People with DiGeorge Syndrome may suffer from heart problems; including Tetralogy of Fallot, pulmonary atresia - VSD, truncus arteriosus and sometimes simpler lesions like a ventricular septal defect. These are usually treatable with surgery.
Half of all children with Down syndrome have a heart problem. These include patent ductus arteriosus, atrial septal defect, ventricular septal defect, Tetralogy of Fallot and atrioventricular septal defects. Some of these may not require surgery as some may close by themselves (patent ductus arteriosus, atrial septal defect, ventricular septal defect).
All babies who have Tetralogy of Fallot require corrective surgery and sometimes, more than one operation is necessary.
A Rastelli Procedure is carried out which involves closing the hole inside the heart (VSD) and the pulmonary artery connected to the heart by a homograft (cadaver valve).
Small babies, especially those with hole in the heart have an increased food requirement and may need special milk.
Special diets are not normally necessary for those with heart disease. As with everyone it is important to have a balanced diet and not to eat to excess. It is however important to maintain a normal weight - excess weight means more work for the heart.
Children and adults with congenital heart disease are at an increased risk of having a heart infection. Whilst this is rare, the chances of it occurring can be reduced by taking precautions.
Infections in the heart can occur for no apparent reason but are more common if the teeth are rotten - germs spread into the blood stream and infect the heart. Good dental hygiene is therefore important as are regular visits to the dentist.
If dental treatment is required then some procedures can cause germs to spill into the blood and infect the heart.
It is therefore important that the dentist is informed about the heart condition before treatment. The usual method of avoiding this problem is to give a single dose of antibiotics one hour prior to the treatment to kill any germs beforehand.
Children who have Tetralogy of Fallot (if there are still residual problems) are restricted to light exercise (like golf, cricket).
Exercise is important even in those with heart disease. It improves the heart function and general sense of well being. It is associated with increased life expectancy and a reduced risk of heart disease in later life. In addition physical activity helps with controlling weight and reducing blood pressure.
There are different types of exercise. In static exercise, the muscles contract but there is little joint movement eg weight lifting. In dynamic exercise, the muscles contract and also move the joints eg running. Each places different stress on the body and cardiovascular system. In general, most types of sports are a mix of the two.
Children usually take part in more rigorous exercise at school as they grow older. In Singapore, Physical Education (PE) tends to teach games skills rather than competitive sports. However pupils may take up sports for their co-curricular activities (CCA) where training is more intense and competitive. Training for the NAPFA test is also intensive and some pupils with heart problems may have difficulty with the 2.4k run as they often perform less well at endurance type activities.
Parents or patients must seek the advice of their own doctor when deciding how much exercise and to what level is safe - particularly as there are no published guidelines for activity levels in children.
The Bottom Line
Most children with heart disease can have all the normal vaccinations at the appropriate time.
However some children with an immune deficiency (DiGeorge syndrome or an isomerism) and those who are receiving immunosuppression - for example following transplantation require a different vaccination schedule.
Before travelling anywhere unusual or a long distance make sure that you / your child have:
Those with cyanotic heart disease ("blue" due to reduced oxygen in the blood) can still travel but aircraft at high altitudes have less oxygen in the air than at ground level and thus, the blueness may be more apparent. This does not usually cause symptoms but if necessary, airlines can arrange for additional oxygen to be available on the aircraft.
For long aircraft flights, it is sensible to use the support stockings and take aspirin or an equivalent unless your doctor advises against it.
Most children with heart disease are no more prone to infections than any other children. Some however are likely to get chest infections - particularly those with holes in the heart (ASD, VSD, PDA).
In addition, some heart diseases are also associated with an immune deficiency and infections are therefore more common. Majority of childhood infections are caused by viruses which get better without antibiotics. If you are unsure of the course of treatment, seek professional medical help.
Most children with heart disease do not require medication.
However, in some cases, medication is required to:
Majority of these medicine have been used for many years and are very safe but as with all drugs, side-effects may occur, especially if there is another illness or change in other medications. If unusual symptoms or side-effects occur while on medication, it is important to inform the doctor immediately.
Most women with heart disease are able to undergo a normal pregnancy and delivery.
The exceptions are those with severe cyanosis when there is usually insufficient oxygen in the blood supply to the placenta to sustain the baby. Most of these pregnancies are spontaneously aborted.
Women with pulmonary hypertension (high lung artery pressure) are usually advised to not get pregnant as it poses a life-threatening risk.
It is essential that medical advise be taken, preferably before the event so that the pregnancy can be monitored and treatment can be undertaken early, if necessary.
If a woman has a heart problem, then there is an increased risk (around 6%) of her child having a problem as well. For a man, the risk is 2%. If the couple has had a previously affected child, the risk is also about 2%. The actual risk varies considerably between various heart conditions.
There has been evidence showing that consuming vitamins for 3 months prior to and during the first 3 months of the pregnancy can reduce the chances of heart disease occurring in the baby.
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