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Atrial and Ventricular Septal Defects


The Manual's Editorial Staff

Reviewed/Revised May 2022 | Modified Sep 2022
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The heart has 4 compartments (chambers), 2 on the right and 2 on the left. The chambers relax to fill with blood, and then contract to pump the blood out.

  • The 2 upper chambers (the right atrium and left atrium) let blood into the heart

  • The 2 lower chambers (the right and left ventricles) pump blood out

  • The 2 right chambers pump blood returning from your body to your lungs

  • The 2 left chambers pump blood returning from your lungs to your body

Blood goes to your lungs to pick up oxygen and get rid of carbon dioxide.

What are atrial and ventricular septal defects?

A septum is a wall between 2 chambers.

  • Atrial and ventricular septal defects are holes in the walls that separate the left and right sides of the heart

  • Babies who have these holes are born with them

  • The holes let some blood flow the wrong way through the heart

  • The bigger the hole, the more blood flows the wrong way

Atrial septal defects (ASD) are holes between the upper chambers of the heart (the atria).

Ventricular septal defects (VSD) are holes between the lower chambers of the heart (the ventricles).

Sometimes, children with an ASD or VSD also have other heart defects.

Septal Defect: A Hole in the Heart's Wall

A septal defect is a hole in the wall (septum) that separates the heart into the left and right sides. Atrial septal defects are located between the heart's upper chambers (atria). Ventricular septal defects are located between the lower chambers (ventricles). In both types, some oxygenated blood, intended for the body, is shortcircuited. It is returned to the lungs rather than pumped to the rest of the body.

Septal Defect: A Hole in the Heart's Wall

What causes ASDs and VSDs?

Babies who have an ASD or VSD are born with them. Doctors aren't sure what causes them.

What are the symptoms of ASDs and VSDs?

Symptoms depend a lot on how big the hole is and exactly where it's located.

An ASD usually doesn’t cause symptoms, though sometimes a child grows more slowly than expected. If your child has a large ASD that isn't treated, the child may have health problems in adulthood such as:

A VSD that's small may not cause any symptoms. But larger VSDs usually start causing problems when a baby is 4 to 6 weeks old. Symptoms include:

  • Faster breathing

  • Difficulty feeding

  • Sweating while eating

  • Slow weight gain

If a VSD isn't treated, it can cause:

  • High blood pressure in the lungs (pulmonary hypertension)

How can doctors tell if my child has an ASD or VSD?

Doctors suspect ASD or VSD if they hear certain types of heart murmurs (an unusual sound made by abnormal blood flow through the heart). Doctors confirm the diagnosis by:

They'll also do other tests such as:

How do doctors treat ASDs and VSDs?

Small ASDs and VSDs often close up on their own before the child turns 3 years old. Treatment depends on the size of the hole and your child’s symptoms.

If an ASD hasn't closed on its own by the time a child is 2 or 3, doctors may:

  • Insert a catheter (thin, flexible tube) through a vein to reach your child’s heart and plug the hole with a small device

  • Sometimes, do surgery to patch the hole in the heart

A small VSD doesn't usually need treatment. If treatment is needed, doctors may:

  • Do surgery to close the hole

Before surgery, doctors usually give your child heart medicines to help with symptoms. The medicines may also allow time for the hole to close on its own.

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