What
is an echocardiogram? It is a scan
of the heart using ultrasound (that is sound waves not x-rays). It produces pictures
of the heart as it is beating and shows the blood flowing through the heart valves.
Why
are you having an echo? The pictures
of the beating heart are produced on a screen monitor, so the the doctor can tell
whether or not the heart muscle is contracting properly and the heart valves are
working normally. Other heart problems may be identified.
Do
you need any preparation? No preparation
is needed for this test but it is helpful if you can wear loose clothing that
is easy to take on and off. Please bring your appointment letter with you, if
you have had surgery for a valve replacement please bring any information with
you. You can continue to take your usual medications unless instructed otherwise
by your doctor.
What does it involve? An echocardiographer (a technician) or doctor will
usually perform the scan. Plese do not hesitate to ask any questions you may have
about the test. The test takes place in a private room. You will need to remove
your clothes to the waist, and lye on a bed or couch. Wires and sticky pads (electrodes)
are attached to you to monitor your heart rate. Using a small, hand-held ultrasound
probe, with some jel on the end the technician /doctor will move it over your
chest. This will transmit pictures onto a screen and record them on video tape
or computer discs. You may hear some wooshing sounds, these come from blood pulsing
through your heart. the scan can take about 20-40 minutes. This is a very safe
test: there are no known risks.
Additional
procedures
A) Contrast Study Occasionally a 'contrast study' may be needed following
on from the echocardiogram, using a liquid 'contrast' to outline certain areas
of the heart. This involves having a small injection into a vein in your arm.
The contrast is harmless except with certain allergies (particularly an allergy
to eggs). There is a risk of slight bruising around the site of the injection;
there is also a very small risk of an allergic reaction to the contrast. Please
speak to your doctor before the test if you have any concerns about these risks
B)
Bubble Contrast Study
Click twice on the play button to run the video
Patients
suffering Transient Ischaemic Attacks (TIAs), severe migraine with aura or a stroke,
may have a 'hole in the heart' whereby blood clots or substances can pass from
the right side of the heart (or low pressure system) to the brain without being
filtered by the lungs. These defects can be small e.g. a 'patent foramen ovale'
, or large - atrial septal defect. It is worth detecting these defects because
they can now be closed without open heart surgery. All patients should be screened
with a bubble contrast test.
This test is designed to look for a 'hole in the
heart'. It is mildly invasive so you will need to give informed consent. A venflon
cannula is placed in the right forearm. Three 10mL syringes are filled with 0.9%
normal saline. A fourth syringe containing 2 mL of air is used with a three way
tap to agitate/mix the air into the saline in order to create a solution of micro
bubbles that can be seen with ultrasound scanning. You will be then asked to perform
some simple manoeuvres such as coughing; holding your nose and pushing down, and
after practicing, lie on the left side position so that the echocardiographer
can obtain views of your heart. The whole procedure
takes about 45 minutes and you will be able to go home shortly afterwards. Please
speak to your doctor before the test if you have any concerns about these risks
C)
Dobutamine Stress Echo Study What is a dobutamine Stress Echocardiogram? A stress echocardiogram is a test
which allows your doctor to assess your heart at rest and during 'stress' when
it is beating faster. A drug called Dobutamine is used to gradually increase your
heart rate, so that the doctor can assess the response of the heart as the heart
rate increases, and detect any changes in the function of the chambers or valves
of the heart.
Do I need to do anything
before the test? You
must stop taking beta-blockers for 48 hours prior to the test, and omit any diuretics
on the day of the test. The test is usually undertaken in the afternoon,
therefore you are asked to have a light meal and no caffeine prior to your test.
Please inform the department if you are diabetic.
What will happen? There will be a sonographer and
a specialist cardiac doctor with you during the procedure. You will be asked to
bring along a list of medication with you to the appointment. Please inform staff
of any known allergies or reactions to drugs.
The sonographer will go through
the procedure, then will weigh you, in order to calculate the correct amount of
Dobutamine to use. A resting blood pressure and ECG
will be taken. If you have not recently had an ordinary echocardiogram, the sonographer
will record a baseline scan.
The doctor will insert a small cannula into
your left arm, through which the Dobutamine infusion will run. The amount of Dobutamine
will be increased every three minutes, to gradually increase your heart rate.
The sonographer will scan several times during the test to assess how your heart
is responding to the increased 'stress'. The doctor may inject a small amount
of contrast agent when the sonographer is scanning. This is to increase the image
quality, and will not affect you in any way. An additional drug called Atropine
may be given in the latter stages of the test to increase your heart rate.
Your ECG and blood pressure
will be monitored throughout the procedure. Once the test has finished, the effects
of the drug will wear off within a few minutes. You will remain monitored until
your heart rate and blood pressure return to normal.
What will happen after
the test? You will
be asked to remain within the department for at least 45 minutes after the test.
Your heart has been stressed and it is important to be fully recovered within
the department before returning home. We ask that you do not drive yourself home
or take public transport on your own. Please bring a relative or friend with
you to accompany you home.
Are there any risks or
side effects? Some
side-effects of a Dobutamine stress echo are similar to exercise. You may feel
hot, sweaty or flushed, and you may feel your heart pounding and your pulse racing.
These are normal reactions and will wear off soon after the procedure is finished.
If Atropine has been given you may experience blurred vision and a dry mouth. Occasionally
Dobutamine can cause angina, breathlessness or palpitations. In rare cases drugs
can be given to counter-act the effects of Dobutamine.
If
you have any questions regarding the procedure, please contact the Cardiac Department
and speak to one of the senior echocardiographers.
You
will be contacted by a member of the clerical staff a week before your appointment
to confirm attendance
