Closure of Atrial Septal Defect

What is an Atrial Septal Defect?

An atrial septal defect (ASD) is most commonly known as a hole in the heart. It is a type of congenital heart condition, where there is an opening or hole in the wall (the septum) of the top chambers of the heart (the atria). Blood that is oxygenated flows from the left atrium through the hole in the septum into the right atrium of the heart and mixes with oxygen-poor blood. (Diagram 1)

If the hole in the heart is small, it may not cause symptoms because the heart and lungs don’t have to work harder. If the hole is large, however the only abnormal finding may be a murmur (noise heard with a stethoscope).

The main risk of a large ASD is a large volume of blood that is being pumped into the lungs from both right and left atrium. This large volume over time can cause permanent damage to the blood vessels that carry the blood to the lungs. Enlargement or failure of the right side of the heart can cause tiredness, shortness of breath or arrhythmias (heart rhythm disturbances).


Frequently Asked Questions

This is a guide only, please contact your Cardiologist or hospital for further information.

If the opening is small, surgery and other treatments may not be needed. Many small ASDs often close on their own.

There are two ways that an ASD can be closed or repaired. The first by cardiac catheterisation uses a device inserted into the opening
to plug it or with open-heart surgery.

If the ASD is an unusual position within the heart, or if there are other heart defects then the ASD can’t be closed with the catheter technique
and surgery is required. This is usually done in early childhood to prevent complications later.

It is important that you bring a list of your current medication with you on the day of your procedure.

You will need to fast 6 hours before your procedure, no solid food.
You can have clear liquids (such as water, apple juice) up to 2 hours before your procedure.

Bring an overnight bag with including dressing gown and slippers.

An imaging test called angiography or cardiac catheterisation, (injection of contrast or dye followed by an x-ray motion picture) is used to visualise the heart better.

An ASD closure device is threaded through the catheter to the specific location of the heart wall defect. Once in the correct position, the ASD closure device is allowed to expand its shape to cover each side of the hole. This device remains in the heart permanently to stop the abnormal flow of blood between the two atria of the heart. Once the closure device is in the correct position the catheter is removed and the procedure is finished. The anaesthetist will wake you up, and you will return to the recovery unit.

Once the procedure is completed, you will need to lie flat for a couple of hours as there is a small risk of bleeding from the site.

Typically you will spend one night in the hospital after the procedure. You will spend the night on the inpatient cardiology unit.

An Echocardiogram or an ultrasound of the heart will be done the following morning to check that the device is in the correct position.

General Instructions

You will need to take things easy over the next couple of days.  There will be a small dressing over the site, and it is important to keep it clean and dry. The nurse on the ward will put a new dressing over the area on the day of discharge.  There may be a small bruise, and the site may even be tender over the next couple of days. An ice pack may be useful, and your doctor may prescribe a mild pain killer.


You will need to take aspirin for six months after the procedure. Aspirin will help to prevent small blood clots from forming around the device. You will be given a prescription for aspirin before you are discharged home from the hospital.

Dental Treatments

You will need to take antibiotics before and after dental treatments for six months after the procedure. These drugs help prevent a heart infection called infectious endocarditis.

Follow-up Appointment

Your will receive an appointment for follow-up about 6 months after the procedure.

Closure of Atrial Septal Defect