An atrial septal defect (ASD) — sometimes called a hole in the heart —
is a type of congenital heart
defect in which there is an abnormal opening in the dividing wall between the
upper filling chambers of the heart (the atria).
In most cases, ASDs are diagnosed and treated successfully with few or no complications.
What Happens in an Atrial Septal Defect?
In an atrial septal defect, there's an opening in the wall (septum) between the
atria. As a result, some oxygenated blood from the left atrium flows through the hole
in the septum into the right atrium, where it mixes with oxygen-poor blood and increases
the total amount of blood that flows toward the lungs.
The increased blood flow to the lungs creates a swishing sound, known as a heart
murmur. The murmur, along with other specific heart sounds, often is
the first tip-off to a doctor that a child has an ASD. ASDs can be located in different
places on the atrial septum and can vary in size.
What Causes Atrial Septal Defects?
Children with ASDs are born with the defect. ASDs happen during fetal development
of the heart. The heart develops from a large tube, dividing into sections that will
eventually become its walls and chambers. If there's a problem during this process,
a hole can form in the wall that divides the left atrium from the right.
In some cases, the tendency to develop an ASD might be inherited (genetic).
Genetic syndromes can cause extra or missing pieces of chromosomes that can be associated
with ASD. Most ASDs, though, have no clear cause. It's also not clear why ASDs are
more common in girls than in boys.
What Are the Signs & Symptoms of an Atrial Septal Defect?
The size of an ASD and its location determine the symptoms it causes. Most kids
who have ASDs seem healthy and appear to have no symptoms. Most feel well, and grow
and gain weight normally.
Children with larger, more severe ASDs, though, might have some of
these signs or symptoms:
An ASD that isn't treated in childhood can lead to health problems later, including
an abnormal heart rhythm (an atrial arrhythmia)
and problems in how well the heart pumps blood.
As kids with ASDs get older, they also might be at an increased risk for stroke
because a blood clot could form, pass through the hole in the septum, and travel to
the brain. Pulmonary hypertension (high blood pressure in the lungs) also may develop
over time in older patients with larger untreated ASDs.
Because of these possible complications, doctors usually recommend closing ASDs
early in childhood.
How Are Atrial Septal Defects Diagnosed?
After hearing the heart murmur that suggests a hole in the atrial septum, a doctor
may refer a child to a pediatric cardiologist, a doctor who specializes
in diagnosing and treating heart disease in kids and teens.
The cardiologist might order one or more of these tests:
chest X-ray: an
image of the heart and surrounding organs
echocardiogram (echo): a
picture of the heart and the blood flow through its chambers. This is often the primary
tool used to diagnose an ASD.
How Are Atrial Septal Defects Treated?
Treatment of an ASD will depend on a child's age and the size, location, and severity
of the defect.
Very small ASDs might not need any treatment. In other cases, the cardiologist
may recommend follow-up visits for observation.
Usually, though, if an ASD hasn't closed on its own by the time a child starts
school, the cardiologist will recommend fixing the hole, either with cardiac catheterization
or heart surgery.
Many ASDs can be treated with cardiac
catheterization. In this procedure, a thin, flexible tube (a catheter)
is inserted into a blood vessel in the leg that leads to the heart. The cardiologist
guides the tube into the heart to make measurements of blood flow, pressure, and oxygen
levels in the heart chambers. A special implant is positioned into the hole and is
designed to flatten against the septum on both sides to close and permanently seal
In the beginning, the natural pressure in the heart holds the device in place.
Over time, the normal tissue of the heart grows over the implant and covers it entirely.
This nonsurgical technique leaves no chest scar, has a shorter recovery time than
heart surgery, and usually needs just an overnight stay in the hospital.
There's a small risk of blood clots forming on the closure device while new tissue
heals over it, so kids who had a catheterization take a low dose of aspirin for 6
months after the procedure. Over time, the normal tissue of the heart grows over the
device and the aspirin is no longer necessary.
After catheterization, a child should take it easy for a few days and might need
to skip gym class or sports practice for a week or two.
Sometimes, when the ASD is very large or close to the wall of the heart, a device
cannot be safely used and heart surgery is needed to close the defect.
If your child has surgery, he or she will get general
anesthesia and won't feel pain or be able move around during the surgery. The
surgeon will make a cut in the chest, then stitch the hole in the atrial septum closed
or sew a patch of manmade surgical material (such as Gore-Tex) over it. Eventually,
the tissue of the heart heals over the patch or stitches, making the area smooth and
nearly normal in appearance.
Kids usually can leave the hospital 3 to 4 days after surgery, if there are no
problems. The first few days at home, your child should relax in bed or on the couch
doing quiet activities such as reading, sleeping, and watching TV. Your doctor will
let you know when your child can go back to school.
It takes about 6 weeks for a chest incision to heal. After that, if there are no
problems and the doctor say it's OK, your child should be fully recovered and able
to return to normal activities.
Heart surgery does leave a permanent scar on the chest. It will be sore at first,
so the doctor might prescribe a pain reliever, or recommend acetaminophen
or ibuprofen. Your child
might feel numbness, itchiness, tightness, and burning around the cut, although these
shouldn't be severe.
For 6 months following catheterization or surgical closure of an ASD, antibiotics
are recommended before routine dental work or surgical procedures to prevent infectiveendocarditis (an infection of the inner surface of the heart). When
the heart tissue has healed over the closed ASD, most patients no longer need to worry
about the risk of infective endocarditis.
Your doctor will discuss other possible risks and complications with you before
After their ASD is closed and they've had plenty of time to heal, most kids have
no further symptoms or problems.
What Else Should I Know?
In the weeks after surgery or cardiac catheterization, the cardiologist will check
on your child's progress. Your child might have another echocardiogram to make sure
that the heart defect has closed completely.
Most kids recover from treatment quickly, and will just need regular follow-up
visits with their cardiologist. You might even notice that within a few weeks, your
child is eating more and is more active than before surgery.
However, some signs and symptoms might indicate a problem. If your child is having
trouble breathing, call the doctor or go to the emergency department immediately.
Also call the doctor if your child has any of these symptoms:
a bluish color around the mouth or on the lips and tongue
poor appetite or difficulty feeding
failure to gain weight or weight loss
listlessness or decreased activity level
a lasting or unexplained fever
increasing pain, tenderness, or pus oozing from the incision
Having your child diagnosed with a heart condition can be scary. But the good news
is that your pediatric cardiologist will be very familiar with ASDs and how best to
manage the condition. Most kids who've had an ASD corrected go on to live healthy,