An atrial septal defect (ASD) is a hole between the upper chambers (atria) of the heart. The most common is called an ostium secundum ASD, located in the center of the wall separating the atria.

Depending on an ASD’s size and location, it can allow blood to mix between the atria, and cause too much blood to flow to the lungs. As a result, the heart and lungs have to work harder than they should, putting a strain on the body.

(A hole between the heart’s lower chambers is called a ventricular septal defect, or VSD.)

ASDs are among the most common types of congenital heart disease. Some ASDs are minor and go away on their own. Others require treatment. Many occur as part of other heart conditions, like partial anomalous pulmonary venous connection (PAPVC) or Scimitar syndrome – so it’s important to look at the entire heart, and understand or rule out other problems.

Families rely on Connecticut Children’s Heart Center for exactly that. We use advanced imaging technology like echocardiography and cardiac magnetic resonance imaging (MRI), and bring together specialists in cardiac catheterization, congenital cardiac surgery and more to determine the right plan of care.

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What Are the Signs and Symptoms of Atrial Septal Defect?

In less severe cases, many children with an ASD have only mild symptoms, or no symptoms at all. They might not even be diagnosed until later in life.

More serious ASDs may have the following signs.

  • Heart murmur
  • Heart beat that’s too fast, too slow or irregular
  • Trouble breathing
  • Lung problems and infections, such as pneumonia
  • Poor appetite
  • Poor growth
  • Low energy

What Causes Atrial Septal Defects?

ASDs develop before birth, when the inner wall (septum) dividing the left and right sides of the heart doesn’t form properly, leaving a hole. Sometimes, this condition is passed down from a parent. But most of the time, ASDs seem to occur by chance, with no clear cause.

How is Atrial Septal Defect Treated?

Some smaller ASDs close on their own, or simply need a heart doctor to keep an eye on them. Others need a special procedure.

ASD transcatheter repair: Minimally invasive procedure that uses a long, thin tube (catheter) to insert a mesh implant in the ASD, sealing the hole

  • ASD closure: Open-heart surgery to close the hole using stitches or a patch
  • If needed, correct any other heart defects – for example, the Warden procedure to address PAPVC, a condition that often occurs in patients with ASDs

Some patients with ASDs need to check in regularly with their doctor throughout life. Connecticut Children’s Heart Center provides expert care close to home, continuing in adulthood with our nationally accredited Adult Congenital Heart Disease program.

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