An exercise stress test is sometimes known as an exercise tolerance
test (ETT) or stress electrocardiogram. It is a method of measuring
how your heart and blood vessels respond to physical exertion.
During this diagnostic
test, you will wear electrodes which are connected by leads to
a monitor. By observing this monitor, the physician can record
your heartbeat during the test. The exercise you will perform
consists of walking on a treadmill.
does my doctor want me to undergo this test?
You may have presented your doctor with symptoms of heart disease
such as chest or arm pain, shortness of breath, dizziness, fatigue
or swelling of your feet and ankles. Based upon your symptoms,
your doctor may want to determine whether you have heart disease
such as coronary artery disease (CAD).
artery disease or atherosclerosis, occurs when a build up of fat,
cholesterol and other substances on the inner walls of the coronary
arteries, block the flow of oxygen rich blood. If blood flow is
completely blocked, the heart doesn't get the oxygen it requires,
and the heart muscle may become permanently damaged. If
you have known CAD, the stress test can also provide some information
to your physician as to the severity of the disease.
ETT can also be used to objectify your exercise capacity, if you
have disease of your heart valves or if you have heart failure.
doctor may order a stress test after you have undergone corrective
surgery such as coronary bypass surgery or balloon angioplasty,
to help him/her design a safe rehabilitation program for you.
it a risky or dangerous test?
An exercise stress test is extremely safe. There are some risks
associated with the test. Complications are very rare. The clinician
performing the test will explain the risks and benefits of the
procedure and obtain your informed consent before the test.
should not undergo exercise stress testing if you have any of
the following conditions: severe congestive heart failure; life
threatening abnormal heart rhythms, heart infection, severe valve
disease; severe hypertension; or any medical condition that precludes
you from walking safely on a treadmill.
preparations should I make before the test?
Do not eat three to four hours before the test. If you have
diabetes, ask your physician what you may eat.
any medications you are currently taking with your doctor. You
may take approved medications with water.
comfortable clothing and comfortable shoes or sneakers.
long will the test take?
The entire test, including preparation, takes about 45 minutes.
Allow extra time for check in.
I have any additional responsibilities during the test?
You should tell the doctor if you feel any of the following symptoms
during the test: chest, arm, or jaw discomfort; severe shortness
of breath; fatigue; dizziness; or leg cramps or soreness during
will happen during the test?
The areas where the electrodes will be placed are first cleaned
with alcohol and then with a slightly abrasive material.
12 electrodes will be placed on your chest. A blood pressure
cuff will be placed around your arm so that your blood pressure
can be measured throughout the test
the test, a resting ECG, blood pressure, and pulse levels are
taken. ECG leads are kept in place during the exercise and for
several minutes after the test.
physician will show you how to use the treadmill. During the test,
the treadmill's speed and incline will increase every 3 minutes.
If you're at high risk for coronary artery disease or in poor
physical condition, the grade and speed may be increased in smaller
increments. Most stress tests last 6 to 10 minutes.
you exercise, the supervising clinician will monitor changes in
ECG and in your blood pressure which may indicate that your heart
is not getting enough oxygen. Other signs include chest pain and
unusual shortness of breath.
of fatigue, shortness of breath and sweating are normal during
testing. The clinician will terminate the test early if
he/she believes it's unsafe for you to continue.
the end of the test the clinician may provide a cool down phase
of approximately three minutes.
happens after the test?
When the test is over, you may eat, drink, and return to your
normal routine. Ask your doctor about resuming your medication(s).
doctor may order another exercise stress test called a "nuclear"
is "nuclear" stress testing?
A nuclear stress test allows your doctor to see pictures of your
heart when you are at rest and immediately after you have
exercised. The test can give information about the size
of the heart's chambers, the pumping action of the heart, and
the blood supply to the heart muscle.
test is very similar to the exercise stress test, but differs
in a few ways. You will receive an intravenous injection of a
small amount of a radioactive substance (Thallium or Sestamibi)
during the exercise.
in the exercise stress test, you will have electrodes placed on
your chest, and you will walk on a treadmill.
the exercise portion of the test, you will leave the treadmill,
and go into another room where you will lie flat on a narrow bed.
A nuclear camera will be used to take pictures of your heart.
The radioactive substance, also known as a nuclear tracer, is
taken up by your heart muscle and allows the heart muscle to be
visible for the nuclear camera. The camera moves around
your body as it takes pictures. This part of the test takes
about 15 to 20 minutes.
most cases, it will also be necessary to take pictures of your
heart muscle at rest. Depending on the kind of nuclear tracer
being used, these pictures will be taken either before the exercise
portion or after the exercise portion of the test using the same
doctor will discuss the results of the nuclear stress test with
you in a day or two. If the test shows that blood flow is normal
during rest but abnormal during exercise, then the heart isn't
receiving enough blood when you work harder than usual. If the
test is abnormal during both exercise and rest segments, there
probably is limited blood flow to a part of the heart at all times.
If no radioactive substance is seen in a part of the heart muscle,
it is indicative of a prior heart attack.
if I am unable to exercise?
If you are disabled or too sick to perform an exercise tolerance
test using a treadmill, a drug can be administered that increases
blood flow to the heart and thus "mimics" exercise. Then the nuclear
portion of the test can be performed as usual.
you are having a "pharmacological" stress test, as described above,
you should not eat, drink, smoke or have any caffeine for four
hours before the test. Some over-the-counter pain relievers may
contain caffeine. If you have diabetes, consult your physician
is a stress echocardiogram?
An echocardiogram is a diagnostic test which employs ultrasound
(high frequency sound waves) to obtain moving and still pictures
of your heart. It is a safe and painless procedure.
transducer wand is moved across your chest, to produce the sound
waves and receive the echoes as they "bounce" off the heart and
reflect as images on a television-like screen. The pictures are
similar to X-ray images, but the process doesn't involve exposure
to radiation. The pictures are recorded on videotape and paper.
of the information that stress echocardiography can provide includes:
size measurements of the heart's four chambers, pictures of the
appearance and motion of the heart valves, and indications as
to how forcefully the heart contracts and forces blood throughout
happens during the stress echocardiogram?
The treadmill portion of the test resembles that of the exercise
tolerance test. In this case, after your heart rate reaches a
certain limit, you will be asked to lie down for the echocardiography
portion of the test.
echocardiograph operator will place three electrodes on your chest,
and attach them by leads to an ECG machine so that your heart
rhythm can be monitored throughout the test.
operator will put a harmless, odorless gel on your chest. The
gel will feel a little cool and moist at first. The gel helps
the transducer pick up the sound waves from your heart. This device
looks like a wand or a microphone. The transducer both generates
and receives the sound signals.
operator will put the transducer on your chest, directly above
the structures your doctor wants to visualize. He will press firmly
as he moves the transducer in arcs across your chest. This does
may be asked to participate by inhaling, exhaling or holding your
breath at various times during the test. For the remainder of
the time, you should remain still.
stress echocardiogram takes approximately 60 minutes to perform.
is a Dobutamine stress echocardiogram?
If you are unable to exercise, you may be given a drug such as
Dobutamine which mimics the effect of stress on the body. The
echocardiogram procedure is the same as above, except that slowly
you will be given Dobutamine intravenously.
in the drug-induced ETT, you should refrain from eating, drinking
or ingesting caffeine for four hours before test. Again, if you
have diabetes, consult your physician about eating.