Echocardiography (Ultrasound of the Heart)
What is it?
An echocardiogram is a test that uses
high-frequency sound waves (ultrasound) to
create an image of the heart (Figure 1). A
Doppler test uses sound waves to measure the
speed and direction of blood flow. By combining
these tests, a pediatric cardiologist gets
useful information about the heartís anatomy and
function. Echocardiography is the most common
test used in children to diagnose or rule out
heart disease and also to follow children who
have already been diagnosed with a heart
problem. This test can be performed on children
of all ages and sizes including fetuses and
How is it done?
The ultrasound test is done with your child
lying down comfortably on a bed or examination
table. Infants may be able to lie in their
The test is done by a cardiac sonographer (a technologist
with extensive training in ultrasound) and/or by
your pediatric cardiologist. The examiner will
put a few stick-on patches called electrodes on
your child for an electrocardiographic (EKG)
tracing during the exam. He or she will also
put a small handheld device (called a
transducer) on the chest and abdomen. It sends
and receives the sound waves and is connected by
a cable to the ultrasound machine (Figure 2).
The ultrasound machine is a computer that
converts sound waves to pictures. A small
amount of clear gel is used between the
transducer and chest to make sure there is
proper contact. The gel doesnít stain and is
wiped off when the test is over.
The examiner may select and show a variety of
pictures on a TV screen. Youíll be able to see
a picture of the beating heart, and you may be
able to see and hear the flow of blood. The
picture normally changes when the transducer is
moved. Expect to hear loud sounds from the
ultrasound instrument. Portions of the test may
be recorded on videotape or stored as computer
files for later measurement, interpretation and
storage as part of the patient record.
Echocardiographic examinations take 20 to 30
minutes. It is important that your child remain
still to obtain an examination of acceptable
quality. Younger children often require sedation
to allow your cardiologist to obtain a complete
study. In some instances, children may be
comforted by watching a videotape or DVD. If
sedation is needed, your child will be asked not
to eat or drink for several hours prior to
testing. Prior to giving medicine, a physician
or nurse will make sure there are no reasons why
sedation should not be given (i.e, bad cold) and
then explain the procedure to you. The most
commonly used sedatives are chloral hydrate,
which is given by mouth, and midazolam (Versed),
which is placed in your childís nose.
Intravenous medications are rarely needed.
Children usually fall asleep within 30 minutes
and sleep for about an hour. Even though sedated
echocardiograms are very safe, close monitoring
of heart rate, blood pressure, and oxygen is
performed while your child is asleep. When your
child wakes up, he or she may have poor balance
(may last for more than an hour) and should be
watched closely. Your doctor and nurse will
continue careful observation until your child is
fully awake and tolerating juice or milk.
Older children and teenagers usually donít need
sedation and may enjoy watching the test. To
avoid any anxiety, be sure your child knows that
the test is fun, that it doesnít hurt, and that
you or whoever brings your child to the test may
stay in the exam room and watch.
Except for allowing for the possibility of
sedation, you donít need to make any special
preparations. Having your child wear a shirt or
blouse that buttons down the front is helpful.
Your child may eat normally before the test;
bring a bottle if you have an infant or a video
for your child to watch.
Does it hurt?
No. No feeling comes from the sound waves
themselves; sometimes the skin feels mildly
warm. Occasionally thereís mild discomfort from
the transducer pressing on the skin.
Is it harmful?
No. There are no known ill effects of the sound
waves used during a standard echocardiogram.