Atrial Septal Defect (ASD) - Transcatheter device closure

Introduction

The heart has four chambers- two at the top (atria) and two at the bottom (ventricles). The wall between the two top chambers is called the atrial septum. An ASD is a hole in this wall. This hole lets blood flow from the left side of the heart (which pumps to the body) back to the right side (which pumps to the lungs).

 Signs and symptoms

An ASD allows some oxygen-rich blood from the left atria to flow into the right atria and back to the lungs. Over time, this makes the right side of the heart work harder and can make it enlarged.

Children with a small ASD often have no signs. Larger ASDs can cause:

  • fast breathing or feeling short of breath (especially during exercise)
  • frequent chest infections
  • tiredness
  • poor growth

Closing the ASD helps the heart work better, return to normal size and prevents long-term problems.

Diagnosis

An ASD is diagnosed by a doctor by:

  • listening to the heart: they may hear a murmur
  • echocardiogram (heart ultrasound): this confirms the presence, size and location of the hole and how blood flows through it
  • electrocardiogram (ECG): this checks the heart rate and rhythm
  • chest X-ray: this shows the size of the heart and increased blood flow to the lungs 

If you have questions, talk to your child’s cardiologist or cardiac nurse. They are here to support you and your family. 

Treatment

Transcatheter ASD closure is a minimally invasive procedure performed in the cardiac catheterisation laboratory (also known as the cath lab). It closes the hole using a special device, without the need for open-heart surgery. 

Not all ASDs can be closed this way. The hole needs enough tissue around it for the device to stay in place. An echocardiogram gives a good assessment of this information. During the procedure a test called a Trans-oesophageal Echocardiogram (TOE) is done to check for more information.

Trans-oesophageal Echocardiogram (TOE)

  • is a special probe which is placed in your child’s oesophagus (food pipe) while they are asleep under anaesthetic
  • a TOE gives very clear images of the heart
  • only after seeing these images can the doctor be sure the ASD can be closed with a device
  • sometimes the doctor sees something on the TOE that means the ASD cannot be safely closed. If this happens, the procedure is stopped. This is uncommon. 

A transcatheter ASD closure involves: 

The procedure is done under general anaesthetic, so your child will be asleep and feel no pain

A TOE is done to check the ASD and make sure a device can be used

A small tube (catheter) is placed in a blood vessel in the leg (groin)

Using X-ray and TOE guidance, the doctor moves the catheter up to the heart and measures the hole

A special device (like a tiny umbrella or double disc) is delivered through the catheter and placed across the hole

Once in place, the device opens and closes the hole securely

The device is checked with TOE and X-ray before it is released

The catheters are removed, and a small dressing is put on the leg

The procedure takes about 1–2 hours and most children recover quickly.

 Management

Risk and complications

Transcatheter ASD closure is very safe, but all medical procedures have some risks including:

  • bruising or bleeding at the catheter site
  • the device moving (embolization) before it settles – rare
  • temporary irregular heartbeat- very rare
  • small leaks around the device (these often close on their own)- rare
  • infection- very rare

Your child’s cardiologist will explain these and answer your questions before the procedure.

Caring for your child after the procedure

In hospital:

  • Your child will wake up in recovery and be monitored
  • The leg used for the catheter must stay straight for a few hours
  • Most children can eat and drink when awake
  • An echocardiogram and sometimes an ECG will be done to check the device
  • Most children go home later the same day or the next morning 

At home:

  • Remove the dressing after 24 hours
  • No baths or swimming for 72 hours (quick shower is okay)
  • Back to school or daycare after 2 days
  • No rough play, cycling, or contact sports for a week
  • Your child may need aspirin for a few months to help healing
  • A follow-up scan will check the device and heart function