Health Resources

Atrial Septal Defect (Children)

Signs & Symptoms

Small atrial septal defects (ASD) typically do not lead to significant issues due to limited blood flow through the defect. However, larger defects may result in symptoms like breathlessness, poor weight gain and increased susceptibility to infections. Even larger defects might be only detected when a murmur is heard during a medical examination.

What causes it
Approximately 50% of children with Down syndrome have a heart condition, which may include patent ductus arteriosus, atrial septal defect, ventricular septal defect, tetralogy of Fallot and atrioventricular septal defects.

Some of these, such as patent ductus arteriosus, atrial septal defect, ventricular septal defect, may close naturally and not require surgery. In contrast, conditions like Tetralogy of Fallot and atrioventricular septal defects always necessitate surgical intervention, sometimes multiple operations.
About the condition

An ASD is a hole in the wall between the heart's two upper chambers (the atria). While all babies have this opening in the womb, it typically closes within a few days after birth.

The impact of the defect depends on the amount of blood passing through it, which varies based on the defect's size and the child's age.

Patent Foramen Ovale

Very small holes, known as a patent foramen ovale (PFO), are often found in healthy individuals. Small ASDs do not require treatment. Although large defects may decrease in size as the child grows, small defects do not enlarge. Large defects allowing excessive blood into the lungs should be closed to prevent lung damage and premature heart wear.

Diagnosis and Treatment Options

Traditional treatment involves safe open-heart surgery, where the defect is closed using stitching or a patch made of either dacron cloth or the patient's own heart lining (pericardium). Patients can typically return home after five days and resume full activities within a month.

A minimally invasive option, keyhole surgery, is now available. Under anaesthesia, a catheter is inserted through a groin blood vessel to the defect. A device attached to a wire is collapsed, inserted into the catheter and advanced to the defect. As the device reaches the end of the catheter, it springs open, clamping onto the atrial septum to seal the defect. The wire is then detached, and the catheter removed.

Endocarditis prophylaxis is recommended for six months following device closure.

Care Tips


Infants, particularly those with an ASD, may have increased nutritional needs and might require special formula.

Dental Care

Good dental hygiene is essential, especially for children and adults with congenital heart disease, as poor dental health can lead to infections spreading to the heart. Therefore, regular dental check-ups are crucial.

Inform your dentist about the heart condition before any treatment. To prevent germs from entering the bloodstream and affecting the heart, a single dose of antibiotics may be given one hour prior to dental procedures.


Exercise is beneficial, even for those with heart conditions. It improves heart function, overall well-being and is associated with increased life expectancy and reduced heart disease risk in later life. It also aids in weight control and blood pressure reduction.

Different types of exercise, such as static (e.g., weight lifting) and dynamic dynamic (e.g., running), have varying impacts on the body and heart. Children with heart conditions should consult their doctor to determine safe levels and types of exercise, especially in school settings where physical activities can be intensive.


Most children with heart disease can follow standard vaccinations schedule. However, those with immune deficiencies, such as DiGeorge syndrome or an isomerism, or those who are receiving immunosuppression, such as post-transplantation, may require a modified vaccination schedule.

Travel Advice

Before travelling, especially long distances or to unusual destinations:

  • Have a recent medical check-up
  • Ensure appropriate insurance coverage
  • Carry an adequate supply of medication
  • Be informed about the local healthcare quality and accessibility
  • Carry relevant documentation about the heart condition  
  • For cyanotic heart disease patients, be aware of potential oxygen needs during flights
  • Use support stockings and take aspirin or equivalent unless your doctor advises against it


Special diets are not normally required for those with heart disease, but a balanced one is important. Maintaining a normal weight is crucial as excess weight increases the heart's workload.


Children with heart disease are generally not more prone to infections, although some may be susceptible to chest infections or have associated immune deficiencies, particularly those with holes in the heart (ASD, VSD, PDA). Viral infections are common and usually resolve without antibiotics, but medical advice should be sought in case of uncertainty.


Not all children with heart disease require medication. Those who do may need it for fluid reduction, aiding heart pumping, rhythm control or blood thinning.

While these medications are generally safe, side effects can occur, especially with other illnesses or medication changes. Any unusual symptoms or side-should be promptly reported to the doctor.


Most women with heart disease can have a normal pregnancy and delivery. Exceptions may include those with severe cyanosis or pulmonary hypertension, where pregnancy can pose significant risks.

It is essential to seek medical advice before pregnancy so the process can be monitored, and if treatment is necessary, it can be provided early.

The risk of heart disease in offspring varies, with some evidence suggesting that vitamin intake before and during early pregnancy may reduce risks.

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