Atrial septal defect (ASD)



Atrial septal defect is a congenital heart disease where a hole is formed between the left and right part of the atria (upper chamber) of the baby due to abnormal formation of the wall called interatrial septum, which divides the left atrium from the right one. This abnormality allows the oxygen rich blood from the left atrium to flow directly into the right atrium containing oxygen poor blood, which can lead to serious complications. Small ASD may never cause any issues and close on their own in the early years of development, while large ASD can damage the lungs and heart of the baby.

Types of ASD

  • Secundum: The most common type of ASD that occurs in the middle of the atrial septum
  • Primum: A rare defect that occurs in the lower part of the atrial septum
  • Sinus venosus: Another rare kind of ASD, which occurs in the upper part of the atrial septum.

Causes and symptoms

There isn’t any exact known cause of ASD, however, there may be some environmental or genetic factors responsible. Doctors believe chromosome abnormalities, exposure to certain chemicals and genetic defects are the main risk factors. Infected with Rubella infection, excessive use of tobacco, drug and alcohol, diagnosed with diabetes or lupus, obesity and phenylketonuria (PKU) can also increase the chances of ASD.

Symptoms may or may not be visible for many years after the birth, which may include:

  • Fatigue
  • Shortness of breath
  • Swelling of legs, abdomen and feet
  • Heart palpitations
  • Stroke
  • Frequent lung infection
  • Heart murmur


The doctor can first suspect an atrial septal defect in your child during health check up of the baby. He/she can hear the heart murmur through a stethoscope and further perform several tests to confirm it. These tests include:

  • Echocardiogram
  • Chest X-ray
  • Electrocardiogram (ECG)
  • Cardiac catheterization
  • Magnetic resonance imaging (MRI)
  • CT scan


There are several treatment methods to cure atrial septal defects and the doctor will choose the most appropriate treatment options depending on the size of the defect. Small ASD may not cause any issues and don’t require any treatment, which is certainly not the case with large ASD. Below are the key treatment options for ASD:

  • Medical monitoring: If your child is diagnosed with ASD, the cardiologist will monitor the defect for a period of time and see if it closes on its own. After examining the child thoroughly, he/she will decide if the child requires treatment or have any other congenital heart defects.
  • Medications: Medications are used to relieve the symptoms and reduce surgery complications. It does not fix the hole but make the heartbeat stable and reduce risk of blood clots.
  • Surgery: Surgery is the most recommended treatment options chosen by doctors for ASD if the hole is of medium or large size. There are basically two forms of surgery that can fix ASD. The doctor will decide which procedure is best for the child.
    • Cardiac catheterization: This procedure involves inserting a thin tube called a catheter into the blood vessel through the groin and the doctor guide it to the heart with image technique. Using the catheter, the doctor sets a mesh patch or plug and places it to close the hole. The tissues then grow around the mesh, sealing the hole permanently. This is an effective procedure to fix small or medium sized hole.
    • Open heart surgery: This procedure is performed under general anaesthesia using a heart lung machine. An incision is made in the chest and mesh patch is placed to close the gap.


Below are given some of the side effects of atrial septal defect treatment that may occur:

  • Bleeding
  • Infection
  • Breathing issues
  • Allergic reaction to anaesthesia
  • Nausea and vomiting
  • Abnormal heartbeat

Postoperative care


Once the treatment is over, the patient will be moved to the recovery room where his/her vital signs will be deeply monitored. The patient will be required to stay in the hospital for several days.

On discharge, the patient will be given proper guidelines and prescriptions to follow. The patient will need to exercise daily in order to control complications and recover quickly. Breathing exercises will help in increasing the strength of the lungs and heart.

Pain relievers may be given to ease of the pain. Follow a healthy diet that includes fruits, vegetables and whole grains.

Regular visits to the doctor will be required in order to reduce the risk of complications.