Atrial Septal Defect (ASD) in Children
Overview
The
atrial septum is the wall between the two upper chambers of the heart (right and left
atria). An atrial septal defect (ASD) is an abnormal hole in this wall. ASD is a heart
problem that is present at birth (congenital). ASDs are common and account for about
10%
to 15% of congenital heart disease. The clinical significance is typically related
to
the location and size of the ASD.
ASDs can happen on their own. Or they
can happen in children born with other congenital heart defects.
ASDs are classified by their different
location and development:
-
Secundum ASD. This occurs in the middle part of the
atrial septum.
-
Primum ASD. This occurs in the lower part of the
atrial septum close to the tricuspid and mitral valves.
-
Sinus venosus. This occurs in the upper part of the
atrial septum near the veins that drain into the right and left atrium.
-
Coronary sinus ASD. This occurs when there is a
defect in the wall between the coronary sinus and the left atrium.
Patent foramen ovale (PFO) is an
opening between the right and left atria that is normally present in fetal circulation.
It typically closes shortly after birth. But a PFO is not considered an ASD because
no
septal tissue is missing.
Causes
The
heart forms during the first 8 weeks of pregnancy. It starts as a hollow tube and
divides into 4 chambers. These chambers are separated by walls (septa). It's normal
for
the walls to have openings as the fetus grows. The openings usually close shortly
before
or just after birth. If they don't all close, the atrial septum will have a hole in
it.
This is called an ASD. ASDs are often associated with other congenital heart defects.
Often the associated defect causes more problem than the ASD itself.
Some
congenital heart defects may be passed down in certain families. Most atrial septal
defects occur by chance. There is no clear reason why they happen.
Symptoms
Many
children have no symptoms and seem healthy. If the ASD is large, your child may have
symptoms. Your child may:
- Tire
easily
- Have
fast breathing
- Have
shortness of breath
- Grow
slowly
- Have
respiratory infections often
- Have
abnormal heart rhythm (arrhythmias)
Older children and adults with ASDs may have migraine headaches. But it's not clear
if
the ASD is the cause. A small blood clot that forms in the bloodstream that may cause
a
stroke can be linked to ASD in older children and adults. But it does not seem that
closing the defect or taking blood thinners (anticoagulants) decreases risk.
The symptoms of ASD can seem like
other health conditions. Have your child see their healthcare provider for a
diagnosis.
Diagnosis
Your
child's healthcare provider may have heard a heart murmur when listening to your child's
heart with a stethoscope. The heart murmur is from the abnormal flow of blood through
the heart.
Your
child may need to see a pediatric cardiologist for a diagnosis. This is a healthcare
provider with special training in treating heart problems in children. This provider
will examine your child and listen to your child's heart and lungs. They will find
out
where the murmur is best heard and how loud it is. Your child may have some tests,
such
as:
-
Chest X-ray. This test may show an enlarged heart. Or it may show changes in your child's lungs
because of the blood flow changes caused by an ASD.
-
Electrocardiogram (ECG). This test records the electrical activity of the
heart. It shows abnormal rhythms (arrhythmias) that may be caused by an ASD. It can
also find heart muscle stress caused by an ASD.
-
Echocardiogram (echo). This test uses sound waves to make a moving picture of the heart and heart valves.
An echo can show the blood flow through the atrial septal opening and find out how
big the opening is.
-
Cardiac
catheterization.
This test uses a thin, flexible tube (catheter) put near the
heart. Contrast dye is used to get even clearer pictures. In some children, this
procedure may be used to close the ASD.
Treatment
Treatment will depend on your child’s symptoms, age, and general health. It will also
depend on how severe the condition is. The most common type of ASD may close on its
own as your child grows.
Once
an ASD is diagnosed, your child's cardiologist will check your child to see if the
defect is closing on its own. An ASD will often be fixed if it hasn't closed by the
time
a child starts school. The decision to close the ASD may also depend on the size of
the
defect or the symptoms caused by the defect.
Treatment may include:
-
Medicine. Many children have no symptoms and don't need medicine. But
medicine can help some children's hearts work better. For example, water pills
(diuretics) help the kidneys get rid of extra fluid from the body.
-
Surgery. Your child's ASD may be repaired by
surgery. The surgery is done under general anesthesia. The defect may be closed with
stitches or a special patch.
-
Device
closure.
Some children may have their ASDs closed with this procedure. The
healthcare provider uses cardiac catheterization to put a special device (septal
occluder) in the open ASD. The device stops blood from flowing through the ASD. The
ASD must meet certain requirements to be able to be closed in this way.
Complications
Large ASDs may cause lung problems,
such as high blood pressure in the lungs, over time if not treated. This is because
the
extra blood passing through the defect and then into the lungs may harm the vessels
in
the lungs.
Living with
All
children with an ASD need to be cared for by a pediatric cardiologist. Most children
who
have had an ASD repair will live healthy lives. After the repair, your child's
healthcare provider may want your child to take antibiotics. This will prevent an
infection of the heart lining (bacterial endocarditis).
With early diagnosis and repair of an ASD, children usually do very well. They don't
need much follow-up care. Children are more likely to have problems if an ASD is diagnosed
later in life and never repaired. Or they may have problems if complications occur
after closing the defect.
Some children develop high blood pressure in the lungs (pulmonary hypertension). These
children should have follow-up care at a center that specializes in congenital heart
disease.
Talk with your child's healthcare provider about the outlook for your child.
When to Call a Healthcare Provider
Call
your child's healthcare provider if your child has new symptoms or symptoms get worse.
Symptoms may include:
- Tiredness that gets worse
- Troubled
breathing
- Fast
breathing
- Racing
or fluttering heartbeat (palpitations)
- Poor feeding
Key Points
- An ASD
is an opening in the wall dividing the two upper chambers of the heart.
- Symptoms include tiring easily, fast breathing, shortness of breath, poor growth,
arrhythmias, and frequent respiratory infections.
- ASDs
range from small to large.
- Small
ASDs may close on their own. ASDs that are large or cause symptoms can be
repaired.
- Most
children who have had an ASD repair will live healthy lives.
Next Steps
Tips to help you get the most from a visit to your child’s healthcare provider:
- Know the reason for the visit and what you want to happen.
- Before your visit, write down questions you want answered.
- At the
visit, write down the name of a new diagnosis, and any new medicines, treatments,
or
tests. Also write down any new instructions your provider gives you for your
child.
- Know why a new medicine or treatment is prescribed and how it will help your child.
Also know what the side effects are.
- Ask if your child’s condition can be treated in other ways.
- Know why a test or procedure is recommended and what the results could mean.
- Know what to expect if your child does not take the medicine or have the test or procedure.
- If your child has a follow-up appointment, write down the date, time, and purpose
for that visit.
- Know
how you can contact your child’s healthcare provider after office hours. This is
important if your child becomes ill and you have questions or need advice.