Health Resources

Ventricular Septal Defect (Children)

2026/01/29
What is Ventricular Septal Defect?
A Ventricular Septal Defect (VSD) is a hole in the wall (ventricular septum) separating the two lower chambers of the heart (ventricles). Normally, the left side of the heart pumps oxygen-rich blood to the body and the right side of the heart pumps oxygen-poor blood to the lungs. This hole allows blood to travel from the left pumping chamber (left ventricle) to the right pumping chamber (right ventricle) and out into the lung arteries.  

The effect of the hole depends on how much blood is circulating around the lungs and this varies upon the size of the hole and age of the child. Small holes do not allow sufficient blood to pass through to cause any problems. Larger holes allow enough blood to pass into the lungs, causing breathlessness, poor weight gain, and an increased susceptibility to infections. 
What Causes it
In majority of cases, the cause is unknown. During the early stages of heart development in-utero, the wall between the two main pumping chambers (left and right ventricles) is formed from separate tissues and sometimes they fail to meet properly in the middle. 

Some babies have genetic or chromosomal defects which may increase the risk of VSD. This includes conditions like DiGeorge Syndrome or Down Syndrome.  

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, which can make infections, vaccinations and blood transfusions more complicated. They may also 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). Tetralogy of Fallot and atrioventricular septal defects always require surgery, and sometimes more than one operation is necessary. 
Signs & Symptoms
Surprisingly, in newborn babies, even a large hole may cause no problems until the circulation has adjusted fully to being out of the womb, in about a month. The diagnosis is usually readily made (except in the first week or two after birth) by examining the child and hearing a heart murmur as blood passes through the hole. 

Larger holes allow enough blood to pass into the lungs to cause breathlessness, poor weight gain and an increased susceptibility to infections. 
 
Breathlessness can occur in small babies, particularly during feeding. It occurs in some heart conditions, for example, a hole in the heart or a leaky heart valve. Worrying signs include if the skin being sucked in between the ribs or below the lower border of the ribs (recession). 
 
Lung problems can also cause breathing problems, so the advice of a doctor is essential. 
 
Breathlessness on running or other exercise is normal unless it is out of proportion to the exercise undertaken. As a general rule, children should be able to manage as well as their friends. 
 
Blue colouration is common in babies and young children. It is usually confined to the area around the mouth ("muzzle area") and the hands and feet. The colour change usually occurs for no apparent reason and the child is completely well. The technical term for these colour changes is acrocyanosis. It 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 and in others they develop - either as a result of untreated heart disease, in this case, a large Ventricular Septal Defect. 
Diagnosis and Treatment Options
The hole cannot get larger - it either stays the same size or gets smaller and, in many instances, can go away completely. For this reason, holes are not operated upon at birth but left for a few months to see how much they affect the baby and whether or not they are going to get smaller. Whilst this observation period is going on, medical treatment with diuretics (medication to reduce fluid) and extra strength feeds may be necessary. 

Surgery is required if the hole is sufficiently large to cause long term damage to the heart and lungs. Another indication for surgery is if the hole is located near the aortic valve (subaortic VSD) because, over a prolonged period of time, this may cause the valve to leak. Open-heart surgery is necessary to close a VSD. This allows the surgeon to close the hole (usually with a Dacron patch  - cloth like material) whilst the heart is still. If the surgery is successful, and once the VSD is closed, further operations are usually unnecessary. 
 
If the hole is small and not causing a problem then it is usually left alone as the risks of surgery, although small, still outweigh any benefits. 
 
Pulmonary Artery Band is used to narrow the pulmonary (lung) artery and thus reduce the amount of blood flowing to the lungs. It may be required in certain types of single ventricle or tricuspid atresia or when there are multiple ventricular septal defects. The operation is usually performed through the breastbone although sometimes a scar is made through the side of the rib cage. The narrowing is made by wrapping a piece of surgical tape around the artery and drawing it tight. It can be difficult to get the degree of narrowing right at the first attempt, and occasionally the patient will require a re-operation within a few days. 
 
Endocarditis prophylaxis on at risk occasions is necessary for life. 
Care Tips

Dental Care 

Good dental hygiene is essential, 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. 

The use of antibiotics before a dental procedure is not routinely recommended unless they meet the following criteria:  

  1. Patients with a prosthetic valve or where prosthetic maternal has been used to repair a valve.
  2. Patients with previous infective endocarditis.  
  3. Patients with congenital heart disease who are cyanotic or who have shunts/conduits or other prosthesis in place. Those who have had complete repair are considered high risk for the first 6 months after the surgery only. 

Please consult your doctor regarding your condition if you are unsure if your child requires antibiotics prior to dental procedures. 

Exercise 

Children who had Pulmonary Artery Band are restricted to light exercise, such as golf and cricket. 

Exercise is important even for 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 (e.g. weight lifting). In dynamic exercise, the muscles contract and move the joints (e.g. running). Each place 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 focus on games skills rather than competitive sports. However, pupils may take up sport as their co-curricular activity (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. 

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 sports 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.  

Vaccination 

Most children with heart disease can receive 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 recommended to use the support stockings and take aspirin or an equivalent unless your doctor advises against it. 

Diet 

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 as excess weight means more work for the heart. 

Infection 

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

Medication 

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

The majority of these medicines 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 while on medication, it is important to inform the doctor immediately.  

Pregnancy 

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 advice is sought - preferably before the event so that the pregnancy can be monitored and if treatment is necessary, it can be undertaken early. 

If a woman herself has a heart problem, then there is an increased risk that her child will have a heart 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%. These figures represent average risks; the actual risks vary considerably depending on the specific heart condition. There is also some evidence that taking vitamins for 3 months prior to conception and the first 3 months of the pregnancy can reduce the chance of heart disease occurring in the baby.

About Us
The Department of Paediatrics, Khoo Teck Puat – National University Children’s Medical Institute (KTP-NUCMI) is part of the National University Centre for Women and Children (NUWoC)

Our paediatricians provide comprehensive and specialised medical and surgical services for newborns, children and adolescents. 

Click here for information on how to make an appointment with our paediatricians. 
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