What is an atrial septal defect?
An atrial septal defect (ASD) is an opening or hole in the wall that separates the two upper chambers of the heart. This wall is called the atrial septum. The hole causes oxygen-rich blood to leak from the left side of the heart to the right side. This causes extra work for the right side of the heart, since more blood than necessary is flowing through the right ventricle to the lungs.
If the ASD is small enough, it can be closed with a special device. The procedure is done in the heart catheterization lab.
What is heart catheterization?
During heart catheterization, the doctor carefully puts a long, thin tube called a catheter into a vein or artery in your child's neck or groin. The groin is the area at the top of the leg. Then, the catheter is threaded through the vein or artery to your child's heart.
The doctor who does the procedure is a cardiologist, which means a doctor who works on the heart and blood vessels. This may not be your child's regular cardiologist.
What does the closure device look like and how does it stay in place?
The closure device is made of metal and mesh material. It looks like a short tube with different-sized discs (circles) on either end. Before it is put in, the discs are folded so the device will fit in the catheter. When it is in the right place, one disc opens up as the device is moved out of the catheter. The tube portion plugs the hole and the other disc opens up on the opposite side of the hole.
There are small risks of complications from the procedure
Generally, heart catheterization is a fairly low-risk procedure, but it is not risk-free. The doctor will explain the risks of heart catheterization to you in more detail before you give your consent for the procedure. The most common risks with ASD closure are as follows:
The catheter may break through a blood vessel
There is a very small risk that the catheter may break through a blood vessel or the heart wall. To reduce this risk, we use a type of X-ray called fluoroscopy to see where the catheter is at all times.
Your child may develop fluid around the heart
There is a very small risk that your child will develop fluid around the heart after the procedure. Your child will have an echocardiogram on the morning after the procedure so we can check for this problem.
Complications may occur with the closure device
While the device is being put in position, there is a risk that it may be put in the wrong place, move or fall out of the hole. The doctors can see this on an echocardiogram. If this happens, the cardiologist will try to move the device or take it out while the child is in the catheterization lab. If this is not possible, surgery will be arranged to take out the device and close the hole.
Once the device has been in place for some time, there is a small risk that the device may become eroded (worn) and damage the heart.
What happens during the closure procedure
The procedure is performed while your child is under a general anaesthetic. This means that your child will be asleep during the procedure.
Not every ASD can be closed with heart catheterization. Therefore, we first need to measure the ASD to make sure it can be closed with a device in the catheterization lab.
When your child is asleep, we will do a test called a transesophageal echocardiogram. Echocardiogram means a heart ultrasound. Transesophageal means we do the ultrasound with a small probe that is placed in your child's esophagus, the tube that connects the mouth to the stomach. This test will measure the size of the hole and help place the closure device.
- If the test shows that the hole is too big to close with the device, we will wake up your child and send them to the recovery room. Your child's cardiologist will discuss the next steps with you and your child.
- If the hole is small enough and in the right position, we will go on with the catheterization.
During the catheterization, the doctor puts a catheter with a small deflated balloon on the tip through the blood vessel to the hole. The balloon is inflated to measure the size of the hole again. If the hole can be closed with the device, the doctor puts the closure device inside the catheter and places the device into the hole.
Once the device is in place, the doctor takes out the catheter and covers the cut on your child's leg with a bandage.
The procedure will take one to two hours
The procedure usually takes one to two hours, but it can take longer. After the procedure, your child will go to the recovery room to wake up from the anesthetic.
After the procedure
The cardiologist will let you know when your child can go home. Your child will stay in the hospital for at least four to six hours after the procedure. Most children can go home on the same day as the procedure. If your child goes home overnight, you will have to bring them back in the morning to have an echocardiogram. This test is to make sure that there is no fluid around the heart.
If your child needs to stay overnight, they will be transferred to the inpatient unit. Your child will have the echocardiogram the next morning.
For information on what to do after your child goes home, please see Heart Catheterization: Caring for Your Child After the Procedure.
Your child needs to take certain health precautions
Antibiotics to prevent infectious endocarditis
Your child will need antibiotics before and after dental treatments for six months after the procedure. These drugs help prevent a heart infection called infectious endocarditis. Your child's cardiologist will tell you if this is needed for a longer time.
Acetylsalicylic acid (ASA) to prevent blood clots
Your child will need to take ASA for six months after the procedure, to prevent small blood clots from forming around the device. The doctor or nurse will tell you how much ASA to give your child before your child goes home.
Write the instructions and dose here:
Stop giving the ASA and call your family doctor or paediatrician if:
- your child has a cold or fever
- your child is exposed to chickenpox
In general, you should give your child acetaminophen for fever and colds, as directed by your doctor. The doctor will tell you when you can start the ASA again.
If your child starts bruising easily, call your family doctor or paediatrician.
Coming back for a check-up
Your child will be given an appointment to see your regular cardiologist one month after the procedure.
Write the date and time of the appointment here:
Your child will need follow-up appointments every six months for the first two years after the closure. We will do tests to make sure that the ASD is properly closed.
