Exercise
Echocardiogram
(Stress
Echocardiogram, Exercise Echocardiography, Exercise
Echo)
What
is an exercise echocardiogram?
An echocardiogram
is a noninvasive (the skin is not pierced) procedure
used to assess the heart's function and structures.
An exercise echocardiogram is performed to assess
the heart's response to stress or exercise. During
the procedure, a transducer (like a microphone)
sends out ultrasonic sound waves at a frequency
too high to be heard. When the transducer is placed
on the chest at certain locations and angles,
the ultrasonic sound waves move through the skin
and other body tissues to the heart tissues, where
the waves echo off of the heart structures. The
transducer picks up the reflected waves and sends
them to a computer. The computer interprets the
echoes into an image of the heart walls and valves.
After
the resting echocardiogram images have been obtained,
the person will begin to exercise on a treadmill
or stationary bicycle. The physician will compare
the resting echocardiogram with the test done
immediately after exercise.
An exercise
echocardiogram may utilize one or more of four
special types of echocardiography, as listed below:
- M-mode echocardiography
This, the simplest type of echocardiography,
produces an image that is similar to a tracing
rather than an actual picture of heart structures.
M-mode echo is useful for measuring heart structures,
such as the heart's pumping chambers, the size
of the heart itself, and the thickness of the
heart walls.
- Doppler echocardiography
This Doppler technique is used to measure and
assess the flow of blood through the heart's
chambers and valves. The amount of blood pumped
out with each beat is an indication of the heart's
functioning. Also, Doppler can detect abnormal
blood flow within the heart, which can indicate
a problem with one or more of the heart's four
valves, or with the heart's walls.
- color Doppler
Color Doppler is an enhanced form of Doppler
echocardiography. With color Doppler, different
colors are used to designate the direction of
blood flow. This simplifies the interpretation
of the Doppler technique.
- 2-D (2-dimensional)
echocardiography
This technique is used to visualize the actual
structures and motion of the heart structures.
A 2-D echo view appears cone-shaped on the monitor,
and the real-time motion of the heart's structures
can be observed. This enables the physician
to see the various heart structures at work
and evaluate them.
Other
related procedures that may be used to assess
the heart include resting or exercise electrocardiogram
(ECG or EKG), Holter monitor, signal-averaged
ECG, cardiac catheterization, chest x-ray, computed
tomography (CT scan) of the chest, electrophysiological
studies, magnetic resonance imaging (MRI) of the
heart, myocardial perfusion scans, radionuclide
angiography, and ultrafast CT scan. Please see
these procedures for additional information.
An exercise
echocardiogram, obtained after you have exercised
on a treadmill or stationary bicycle, may be performed
for the following reasons:
- to assess the heart’s
function and structures
- to determine limits
for safe exercise in patients who are entering
a cardiac rehabilitation program and/or those
who are recovering from a cardiac event, such
as a heart attack (myocardial infarction, or
MI) or heart surgery
- to assess leg pain
with exercise (also called intermittent claudication)
in patients with suspected occlusion in the
legs' circulatory system
- to evaluate blood pressure
during exercise
- to assess stress or
exercise tolerance in patients with known or
suspected coronary artery disease
- to evaluate the cardiac
status of a patient about to undergo surgery
There
may be other reasons for your physician to recommend
an exercise echocardiogram.
Possible
risks associated with an exercise echocardiogram
include, but are not limited to, the following:
- chest pain
- severely high blood
pressure
- irregular heartbeats
- dizziness
- nausea, and extreme
fatigue
- heart attack (rare)
If you
are pregnant or suspect that you may be pregnant,
you should notify your physician.
There
may be other risks depending upon your specific
medical condition. Be sure to discuss any concerns
with your physician prior to the procedure.
Certain
factors or conditions may interfere with the accuracy
of an exercise echocardiogram. These factors include,
but are not limited to, the following:
- smoking or ingesting
caffeine within three hours prior to the procedure
- chronic obstructive
pulmonary disease (COPD)
- beta-blocking medications
may make it difficult to increase the heart
rate
- Your physician will
explain the procedure to you and offer you the
opportunity to ask any questions that you might
have about the procedure.
- You will be asked to
sign a consent form that gives your permission
to do the test. Read the form carefully and
ask questions if something is not clear.
- Fasting may be required
before the procedure. Your physician will give
you instructions as to how long you should withhold
food and/or liquids. In some cases, cigarettes
and caffeinated beverages, such as coffee, tea,
and cola may be restricted two to three hours
before testing.
- If you are pregnant
or suspect that you may be pregnant, you should
notify your physician.
- Notify your physician
of all medications (prescription and over-the-counter)
and herbal supplements that you are taking.
- Notify your physician
if you have a pacemaker.
- Notify your physician
if you have the following conditions: aneurysm,
severe hypertension (high blood pressure), severe
heart valve disease, severe congestive heart
failure, recent heart attack, pericarditis,
or severe anemia (low red blood cell count).
- For exercise echocardiogram,
plan to wear loose, comfortable clothing for
the exercise portion of the test, as well as
a pair of comfortable walking shoes.
- Based upon your medical
condition, your physician may request other
specific preparation.
An exercise
echocardiogram may be performed on an outpatient
basis or as part of your stay in a hospital. Procedures
may vary depending on your condition and your
physician's practices.
Generally,
an exercise echocardiogram follows this process:
- You will be asked to
remove any jewelry or other objects that may
interfere with the procedure. You may wear you
glasses, dentures, or hearing aids if you use
any of these.
- You will be asked to
remove clothing from the waist up and will be
given a gown to wear.
- You will be asked to
empty your bladder prior to the procedure.
- You will lie on your
left side for the first set of echo images.
A pillow or wedge will be placed behind your
back for support.
- You will be connected
to an ECG monitor that records the electrical
activity of the heart and monitors the heart
during the procedure using small, adhesive electrodes.
Your vital signs (heart rate, blood pressure,
breathing rate, and oxygenation level) will
be monitored during the procedure. The ECG tracing
that will record the electrical activity of
the heart will be compared to the images displayed
on the echocardiogram monitor.
- The room will be darkened
so that the images on the echocardiogram monitor
can be viewed by the technologist or physician.
- The technologist will
place warmed gel on your chest and then place
the transducer probe on the gel. You will feel
a slight pressure as the technologist positions
the transducer to get the desired image of your
heart.
- The technologist will
move the transducer probe around and apply varying
amounts of pressure to obtain images of different
locations and structures of your heart. The
amount of pressure behind the probe should not
be uncomfortable. If it does make you uncomfortable,
however, let the technologist know.
- The different echocardiogram
techniques described above (M-mode, 2-D, Doppler,
and color Doppler) may be used. You will not
be aware of the different techniques except
that during the Doppler or color Doppler, you
may hear a "whoosh-whoosh" sound, which is the
sound of the blood moving through the heart.
- Once the echocardiogram
images have been obtained, you will use the
treadmill or bicycle to begin exercising.
- You will exercise until
you have reached your target heart rate (determined
by the physician based on your age and physical
condition), or until you are unable to continue
due to chest pain, leg pain, severe shortness
of breath, or severe fatigue.
- Once you have reached
your target heart rate, you will continue to
exercise for another minute or so.
- You should notify the
technologist if you feel any chest pain, breathing
difficulties, sweating, or heart palpitations.
- You will again lie
on the table or bed while a second set of echocardiogram
images is obtained.
- After the procedure
has been completed, the technologist will wipe
the gel from your chest and remove the ECG electrode
pads. You may then put on your clothes.
You
may resume your usual diet and activities unless
your physician advises you differently.
Generally,
there is no special type of care following an
exercise echocardiogram. However, your physician
may give you additional or alternate instructions
after the procedure, depending on your particular
situation.
|
