Atrial Septal Defect
(Atrial Septal Defect; Atrioventricular Canal Defect; Atrioventricular
Septal Defect; Endocardial Cushion Defect; Ventricular Septal Defect)
Septal defects are problems with the structure of the heart. They are
present at birth. Septal defects are located on the inside of the heart.
They are on a wall that separates the chambers of the heart. There are
two upper chambers of the heart called atrium. Two lower chambers of the
heart are called ventricles.
In a healthy heart, the blood flows from the body to the right atrium.
The blood then goes into the right ventricle. The ventricle pumps this
blood to the lungs to pick up fresh oxygen. The blood then returns to
the left side of the heart. It enters the left atrium first, then down
to the left ventricle. The ventricle pushes the blood out to the rest of
Septal defects allow the blood to move between the left and right
chambers. The blood most often moves from the left side of the heart
into the right side. This means that blood that has just returned from
the lungs may end up being sent right back to the lungs. As a result,
both the heart and lungs have to work harder than they need to.
There are three main types of septal defects:
Atrial septal defect (ASD) — a hole in the wall between
the two upper chambers (atrium) of the heart
Ventricular septal defect (VSD) — a hole in the wall
between the two lower chambers (ventricles) of the heart
Atrioventricular septal defect (AVSD) — a combination of
ASD, VSD, and problems with opening between chambers
The stress of pushing extra blood to the lungs may lead to heart
failure. The following information applies to all three of these defects
except where noted.
Ventricular Septal Defect
Copyright © Nucleus Medical Media, Inc.
In most cases the cause is not known. However, in a
small number of cases, a defect may be caused by:
Family history of congenital heart
Exposure to a viral infection, drugs, or
alcohol during pregnancy
For most, there are no known factors that increase your
baby's chance of septal defects. Some medications during
pregnancy have been linked to an increased risk of
septal defects. These medicines include valproic acid
for seizure disorder.
Many people with ASD or VSD do not have symptoms. Large
defects and AVSD may cause:
Shortness of breath
Getting tired easily
High blood pressure in the lungs and possibly
damage to the blood vessels in the lungs (in VSD
An ASD may be found during a regular exam. The doctor
may hear a heart murmur. This is a sound caused by an
abnormal blood flow through a valve in the heart. In
this case it is the extra large amount of blood moving
through the right side of the heart. If
your child's doctor suspects a heart defect, an
echocardiogram may be done. An echocardiogram uses sound
waves to create images of the heart. It can be used to
show the size and shape of the hole in the heart. Other
tests may include:
Electrocardiogram (ECG, EKG) — a test
that records the electrical activity of
Chest X-ray — a test that uses radiation
to take a picture of structures inside
Treatment may depend on the type and size of defect.
There may be some treatment steps for any complications.
Treatment options may include:
ASD treatment options include:
About 40 percent of all ASDs
will close on their own during
the first year of life. This is
more likely to occur with small
An ASD that still exists at age
2 is unlikely to ever close on
its own. If it is not closed in
childhood, it may cause problems
Surgery may be recommended in
children with ASD's past age 2
Some ASDs can be closed without
surgery. A device is placed in
the hole with cardiac
catheterization. This is a
process that send the device to
the heart through a large blood
VSD treatment options include:
Many VSDs will close on their
own during the first year of
life. This is more likely to
occur with small defects.
Small VSDs that do not close
rarely cause problems.
Medium and large VSDs may cause
problems. They may need
supportive treatment in the
first few months of life.
Surgery may be needed in
children with defects that cause
symptoms or do not close after 1
AVSD treatment options include:
Most infants with AVSD will have
symptoms. Therefore they will
Medication may be needed. They
can help the heart beat
strongly, keep the heart rate
regular, or decrease the amount
of fluid in the blood flow.
Physical activity may need to be
Surgery to close the defect.
congestive heart failure — infants with signs of
congestive heart failure may need to take
The type of surgery used most often for septal defects
is open-heart surgery. The hole is closed with stitches
or a patch. In AVSD, the abnormal valves are also
Living With Septal Defects
Certain septal defects may increase the
risk of infections in the heart. You may
need to take antibiotics before certain
medical and dental procedures to
decrease the risk of this infection.
Check with your doctor to see if you
need to do this. If you do need to take
antibiotics, ask your doctor to explain
when they may be needed.
There are no general guidelines for preventing septal
defects. One type
of AVSD is strongly associated with Down syndrome.
Programs have been developed to help some parents reduce
their risk of having a baby with this condition. Certain
maternal health conditions or medications may affect the
baby's health. Talk to your doctor before considering
American Heart Association http://www.americanheart.org/
March of Dimes http://www.marchofdimes.com/
Canadian Cardiovascular Society http://www.ccs.ca/index.php/en/
Canadian Family Physician http://www.cfpc.ca/
Antibiotic prophylaxis. American Dental Association website. Available
. Accessed August 10, 2012.
Congenital heart defects. March of Dimes website. Available at:
Accessed August 10, 2012.
Congenital heart defects. American Heart Association website. Available
. Accessed August 10, 2012.
Patent foramen ovale and other atrial septal defects (ASD). EBSCO
DynaMed website. Available at: http://www.ebscohost.com/dynamed/what.php
. Updated June 2012. Accessed August 10, 2012.
Ventricular septal defect. EBSCO DynaMed website. Available at:
http://www.ebscohost.com/dynamed/what.php . Updated June 2012. Accessed
August 10, 2012.
6/18/2010 DynaMed's Systematic Literature Surveillance
http://www.ebscohost.com/dynamed/what.php : Jentink J, Loane M, Dolk H,
et al. Valproic acid monotherapy in pregnancy and major congenital
malformations. N Engl J Med. 2010;362(23):2185.
Reviewer: Michael Woods
Review Date: 09/2012
Update Date: 00/92/2012