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Home > Events & Health Information > Diseases & Conditions > Heart Conditions > Atrial Septal Defect (ASD)

Atrial Septal Defect (ASD)

Signs & Symptoms

Small holes do not allow sufficient blood across the hole to cause any problems at all. Larger holes allow enough blood to pass into the lungs to cause breathlessness, poor weight gain and an increased susceptibility to infections. Surprisingly even large holes may have little effect and they are only noticed when a doctor hears a murmur.


What causes it

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). Tetralogy of Fallot and atrioventricular septal defects always require surgery and sometimes more than one operation is necessary.


About the condition

There is a hole in the wall between the two collecting chambers (left and right atria). All babies have a hole in this position whilst inside the womb and it should close within a few days of birth. The technical term for this is an atrial septal defect.

The effect of the hole depends upon how much blood is going around around the lungs and this varies upon the size of the hole and age of the child.

Patent Foramen Ovale

Very small holes are known as a patent foramen ovale (PFO) and are commonly found in normal people. Small holes do not require treatment. Many holes may start off large but get smaller as the child gets bigger - small holes however do not get larger. Holes that are sufficiently large to allow a lot of excess blood into the lungs should be closed to prevent lung damage and the heart wearing out prematurely.


Diagnosis and Treatment Options

Although the traditional method of closing the hole uses open heart surgery the operation is very safe. The hole is closed by either stitching or patching it with a cloth material (dacron) or the lining of the patients own heart (pericardium). The patients can usually go home after 5 days and back to full activities within a month.

Key hole surgery is now also possible. Under an anaesthetic a tube (catheter) is passed from the blood vessel in the groin into the hole. The device is attached to a wire by a screw thread, collapsed down and inserted into the catheter. It is advanced through the catheter by pushing the wire. As it reaches the end of the catheter the first disc springs open. The catheter and device are then pulled back so the device is fitting snugly against the left atrial wall. The catheter is then withdrawn, the right atrial disc springs out and the device clamps onto the atrial septum sealing the defect. The wire is then unscrewed from the device and withdrawn and the catheter taken out

Endocarditis prophylaxis is not necessary except for 6 months post device closure.


Care Tips


Small babies - especially those with hole in the heart have an increased food requirement and may need special milk.

Dental Care

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.


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 a 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 sport for their co-curricular activities (CCA) when 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.

As always 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 conditions (even following surgery) can safely participate in sport at all levels
  • Some children with complex heart problems should restrict themselves to certain sports only
  • For a few children competitive sport should not be undertaken
  • For all a certain level of fitness is healthy and should be encouraged


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.

Travel Advice

Before travelling anywhere unusual or a long distance make sure that you:

  • have a recent medical check up
  • have appropriate insurance cover
  • have an adequate supply of medicine
  • are aware of the quality and access to local health care
  • carry the relevant documentation about the heart condition 

Those with cyanotic heart disease ("blue" due to reduced oxygen in the blood) can still travel but aircraft at altitude have less oxygen in the air than at ground level and so 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.


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.


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 therefore are more common. The majority of childhood infections are viruses and get better without antibiotics. In any case of doubt professional medical help should be sort and the doctor will decide if antibiotics are necessary.


Most children with heart disease do not require medication. Some however need them to:

  • reduce the body fluids
  • assist the pumping action
  • control rhythm problems
  • thin the blood

The majority of these medicine have been used for many years and are very safe but like all drugs side effects may occur - especially if there is another illness or a change in other medication. If unusual symptoms or side-effects occur whilst 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  spontaneously abort.

Women with pulmonary hypertension (high lung artery pressure) are not usually advised to get pregnant as there is a serious danger to their life.

As with any medical problem it is essential that medical advise is taken - preferably before the event so that the pregnancy can be monitored and if treatment is necessary it can be undertaken early.

If a women herself has a heart problem then there is an increased risk that her child will have a problem too. The risk is around 6%. If a man has a heart problem then the risk is 2%. If the couple have had a previously affected child then the risk is about 2%.

The risks quoted above are averages - the actual risk varies considerably between the various heart conditions. There is also some evidence that taking vitamins for 3 months prior to and the first 3 months of the pregnancy can reduce the chance of heart disease occurring in the baby.