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Atrial Septal Defect
What conditions are associated with
atrial septal defects?
Some babies born with an atrial
septal defect also have other heart defects or genetic disorders. Some
associated heart defects include:
Mitral valve disease.
Pulmonary stenosis.
Ventricular septal defect (VSD).
Associated genetic disorders
include:
Holt-Oram syndrome.
Down syndrome.
Thrombocytopenia-absent radii (TAR)
syndrome.
What is the difference between an
atrial septal defect and a patent foramen ovale?
An atrial septal defect (ASD) and a
patent foramen ovale (PFO) are both openings in the atrial septum. But ASD is a
congenital heart defect, meaning it’s a problem that occurred while a fetus was
still in the uterus. Septal tissue should’ve formed in that part of the atrial
septum, but didn’t. So a baby is born with a hole in their heart.
A patent foramen ovale isn’t a
congenital heart defect. Tissue isn’t missing from the atrial septum. Instead,
a PFO happens when a normal flap-like opening in a baby’s heart (foramen ovale)
doesn’t seal shut after birth. The foramen ovale is normal, and we all have one
when we’re born. This is a normal pathway to allow oxygen-rich blood from the
placenta to circulate to the fetus’ brain while in the uterus.
When we’re born, we no longer need
the foramen ovale since our lungs start working. So it usually closes on its
own soon after birth and completely seals off in a couple of days or weeks
after. When it doesn’t close on its own, it’s called a patent foramen ovale.
“Patent” means open or failing to close.
A PFO is usually smaller than an
ASD. That’s why it doesn’t usually cause any problems or symptoms. The risk of
symptoms and problems goes up when an opening in the septum is bigger.
PFOs are much more common than ASDs.
Estimates show that about 1 in 4 adults have a PFO. Most people never know they
have this small opening in their hearts. It’s usually harmless, but people who
have a PFO along with heart problems such as atrial fibrillation may face a
higher risk of a stroke.
How does an atrial septal defect
affect a person’s body?
A small ASD doesn’t affect your body
much. But larger ASDs can strain the right side of your heart. That’s because
the right side of your heart now has extra blood it must pump out to your
lungs. Plus, this extra blood flow can slowly damage the blood vessels in your
lungs.
Problems with large ASD include:
Right heart enlargement, which can
lead to heart failure if left uncorrected for a very long period of time.
Abnormal heart rhythm (arrhythmia),
including atrial fibrillation or atrial flutter. At least half of adults over
age 40 with an ASD have an arrhythmia.
Stroke.
Pulmonary hypertension. This is high
blood pressure in the arteries that supply blood to your lungs.
Eisenmenger syndrome. This condition
can happen in people who have an ASD along with severe pulmonary hypertension.
What are the symptoms of an atrial
septal defect?
Even though an atrial septal defect
is present at birth, many people don’t have symptoms until far into adulthood.
Small ASDs (less than 5 millimeters) may not cause symptoms because they don’t
strain the heart or lungs.
Symptoms of an ASD in children
Most children have no signs or
symptoms. The most common (and often the only) sign will be a heart murmur.
Their healthcare provider will notice it when listening to their heart with a
stethoscope.
When children do have other
symptoms, they include:
Being underweight.
Growth delays.
Recurrent respiratory infections.
Although extremely rare, children
with larger ASDs may have symptoms that include:
Arrhythmias.
Easily becoming fatigued when
exercising.
Trouble breathing.
Tell your child’s provider about any
symptoms you notice. Their provider may want to run some tests to check your
child’s heart structure and function.
Symptoms of an ASD in adults
Adults with ASD may feel symptoms by
age 40. Symptoms depend on how much the ASD has strained the heart and lungs.
They include:
Fatigue.
Shortness of breath with exercise.
Heart palpitations.
Fast heartbeat (tachycardia).
Swelling in the arms and legs.
Blue skin color (cyanosis).
If you have any of these symptoms,
call your healthcare provider right away. These symptoms could mean you have an
untreated ASD. Or, they could mean you have another cardiovascular problem that
needs treatment. If you have chest pain, you should call 911 or your local
emergency number.
What causes atrial septal defects?
The exact cause of atrial septal
defects isn’t fully known. However, congenital heart defects are often caused
by genetic changes that happen before birth. Some genetic mutations associated
with ASD affect the NKX2.5/CSX and TBX5 genes.
Some factors can raise a birthing
parent’s risk of having a baby with congenital heart disease. These factors
include:
Alcohol consumption.
Smoking and tobacco use.
Taking certain prescription
medications.
How are atrial septal defects
diagnosed?
Atrial septal defects are diagnosed
through a physical exam along with tests that check your heart’s structure and
function.
Tests to diagnose atrial septal
defects
Your provider will run one or more
tests to diagnose you with an ASD and learn how it’s affecting your heart.
These include:
Electrocardiography (ECG/EKG). An
ECG shows your heart’s electrical activity. It can reveal if you have an
arrhythmia or other problems related to your heart’s electrical system.
Chest X-ray. This test will show if
your right atrium and right ventricle are enlarged. It’ll also show if the
blood vessels in your lungs are affected.
Transthoracic echocardiography
(TTE). This test shows how the left-to-right shunting of blood (caused by ASD)
affects your heart. It can also show details related to pulmonary hypertension.
Transesophageal echocardiography
(TEE). A TEE is an ultrasound taken through your esophagus. It shows the size,
shape and location of an ASD. It can also check your heart valves. TEE is often
used during ASD surgery and percutaneous repair.
Intracardiac echocardiography (ICE).
This is an ultrasound taken inside your heart. A tiny camera (echo probe) is
sent to your heart through a peripheral vein. This test shows the size and
shape of the ASD and the direction of the blood flow across it. It’s often used
during percutaneous (nonsurgical) repair of ASD.
In some cases, Cardiac CT scan or
Heart MRI may be used. They’re most helpful for people with associated defects
or less common forms of ASD.
What is the treatment for an atrial
septal defect?
Atrial septal defects can be closed
through surgery or percutaneous (nonsurgical) repair.
The type and timing of ASD treatment
depends on many factors, including:
ASD type and size.
How the ASD is affecting your heart.
Other conditions you have, like
pulmonary hypertension, valve disease or coronary artery disease.
Small ASDs usually don’t need
repair. However, larger ASDs should be repaired even if they aren’t causing
symptoms. This prevents serious complications down the road.
Once you have signs of heart or lung
damage, repair is essential. Your provider will recommend treatment if:
The right side of your heart is
bigger than normal.
There’s significant shunting (flow
of blood through the ASD).
Your provider may prescribe
medications to treat some symptoms of ASD. But there aren’t any medications
that can close the hole.
If you have pulmonary hypertension,
you may need to take medication before your repair procedure. This medication
treats pulmonary hypertension and makes the procedure safer for you.
Percutaneous (nonsurgical) repair of
ASDs
This type of repair uses a device
(called a septal occluder) to close the hole in your atrial septum. The device
is put in place using a long, thin tube called a catheter. The occluder is
attached to the catheter, which is guided to your heart through a vein in your
groin. When the occluder is released from the catheter, it opens up and seals
the hole. Over time, tissue grows over the occluder, and it becomes part of
your heart.
Percutaneous repair can close most
secundum ASDs and some sinus venosus ASDs. So, this is the method used most
often.
Before the repair, you’ll have a
cardiac catheterization to check the size and location of the ASD and measure
pressures in your heart.
After the repair, you’ll take
blood-thinning medication (anticoagulant or antiplatelet) to keep blood clots
from forming on the device (a possible but rare complication). Your provider
will talk with you about the right type of medication for you and how long you
need to take it.
Surgical repair of ASDs
Surgery is needed for primary ASDs,
coronary sinus defects and most sinus venosus ASDs. These are rare defects that
require treatment by a cardiac surgeon with expertise in congenital heart
disease. Robotic-assisted surgery or minimally invasive surgery may be options
for some people.
A surgical repair usually involves
using a tissue patch to close the ASD. The tissue often comes from your own
pericardium (the membrane around your heart). Some secundum ASDs can be
surgically closed with just sutures and no patch.