The Following Bookmarks may save you some time. Click on the underlined text to go to the section named
A guide to your Nuclear Medicine Heart Scan.
Information Leaflets (on the "Procedures" page)
It can sometimes cause confusion when a patient is sent for a Nuclear Medicine Heart Scan because of the many strange names that are used to describe the tests that can be performed. A referring physician may ask for a Nuclear Stress Test, Thallium Scan, Sestamibi Scan, MIBI Scan, Myoview Scan, Myocardial Perfusion Scan, Gated SPECT with Ejection Fraction, One Day Protocol, Two Day Protocol, a Dipyridamole, Dobutamine or Persantin Scan. All of the above names describe much the same test. Alternatively the patient may be asked to book a Gated Heart Scan at Rest or possibly during Stress, different tests altogether. So why have so many different names been adopted?
Myocardial Perfusion imaging has undergone numerous changes over the past decade. It still involves two main parts. They are the Stress and Resting Studies. The traditional "Stress/Rest Thallium Scan" has, in many institutions been replaced by scans using Technetium (Tc99m) based myocardial perfusion (heart blood flow) agents. The first technetium based agent to gain acceptance was "Sestamibi" (or MIBI). This was the name of the radiopharmaceutical (radioactive tracer) which provided similar information to Thallium yet had the many advantages of the ideal imaging characteristics of Technetium. Next came along "Myoview" a Technetium based agent from a different company which once again could be used for myocardial perfusion imaging. All three provide similar information. One advantage of Sestamibi and Myoview was that the scans could be performed on one day (One Day Protocol) or over two days (Two Day Protocol). Also either the Stress or Resting study can be done first. Another advantage was that a "GATED SPECT" study could be performed. This can provide added information such as Ejection Fraction (the percentage of blood pumped out when the heart contracts), wall motion information and also a better view of the perfusion to the heart muscle when the heart is filled with blood (end-systole) or when it has ejected the blood (end-diastole).
The terms "Dipyridamole", Dobutamine" and "Persantin" refer to the use of drug induced stress in a situation where the patient is unable to perform the usual stress test on our bicycle ergometers (Stress Test Bikes).
Please Click on this link to view the Explanation of a Sestamibi/Myoview Stress Test Pamphlet which we have prepared for patients having myocardial perfusion scans. It has been prepared in MS Word format It can be printed onto A4 paper from your word processor. When printed/copied onto both sides of the page it can be folded into a pamphlet containing information on preparation, an explanation of the test itself and also times taken for different parts. These brochures are also available from your nearest SNI practice.
Click here for a WordPerfect Version of the brochure.
The Text from this brochure appears below.
EXPLANATION OF A
SESTAMIBI/MYOVIEW STRESS TEST
What is a Sestamibi or Myoview Stress test?
A Sestamibi/Myoview stress test determines whether your heart is receiving enough blood from your coronary arteries. That is, if you have any significant blockages in the vessels that supply your heart with blood.
We call this a stress test because we put your heart under stress by increasing its workload (your pulse and blood pressure) and, thus, increasing its demand for oxygen rich blood. What this means is that although your heart may function well under normal conditions, it is this extra load and demand that allows us to see any abnormalities.
No Caffeine for 24 Hours prior to your Myocardial Perfusion Scan (i.e. No coffee, tea, chocolate, Cola or energy drinks or any other beverages or food containing caffeine).
A number of heart and blood pressure tablets may interfere with the accuracy of the test (eg. Betaloc, Tenormin, Noten, Inderal, Cardizem, Theodur, Nuelin). Usually these tablets are stopped 24 - 48 hours prior to the test (see drug list for exact time), but please ask your doctor if this is permissible and which tablets are to be stopped. Sometimes your doctor will ask you to continue all your medications for the test to determine how well they are working.
If you are having the test using the medication with minimal exercise, you may continue all your heart and blood pressure medication.
If you are a diabetic, please inform staff when you book in for your test.
On the morning of the test have a light breakfast, such as toast and/or cereal and juice. DO NOT HAVE ANY CAFFEINE such as TEA, COFFEE or CHOCOLATE (no caffeine for 24 hours prior to the test).
Please bring comfortable clothing suitable for riding or sitting on the exercise bicycle: e.g. shorts or track-pants/trousers and, for women, a blouse that buttons up at the front without metal buttons.
ONE DAY: Please allow a total of 3-5 hours for the test. The first part takes approximately 1 hour and, after a break of 1 to 2 hours, the second part will take approximately 2 hours.
TWO DAY1.5 hrs each day.
You will be given a small injection of Myoview into a vein in your arm and after approximately 30 minutes you will be asked to lie on a scanning bed and pictures of your heart will be taken. It is very important that you lie still for 30 minutes while these pictures are being collected. There are no side effects from the injection.
There is then a short break in the waiting room. You are still unable to have any tea, coffee or any other caffeine based food or drink.
The Stress Test:
While sitting on the bicycle, you are connected to an ECG machine, blood pressure monitor and a small needle is placed into a vein in your arm.
You begin pedalling at a constant speed and every 2 - 3 minutes it is made a little more difficult than before. It is extremely important that you keep the doctor or nurse informed of how you are feeling, especially if experience any chest discomfort or shortness of breath during the exercise test.
If for any reason you cannot exercise, the test can be done using a medication to simulate exercise. This medication is called Dipyridamole and is given as an injection. Most people have minimal side effects from this medication, such as a slight headache, flushing and sometimes angina. You may be asked to pedal the bicycle gently for a few minutes as this helps minimise the side effects.
1 to 2 minutes before you finish exercising, or after the medication, the doctor will give another injection of Sestamibi through the needle in your arm. It is the same injection that you were given in the morning and has no side effects.
When you are disconnected from the monitoring equipment there may be a short break before the scan pictures are started. During this short break you are able to have a cup of tea or coffee and, if diabetic, something to eat.
The scan pictures are then repeated. The Sestamibi will identify any part of your heart that is not receiving enough blood, that is, any significant blockages in the blood vessels that supply your heart.
A full report will be completed and sent to your doctor the following day. If you have any questions, especially regarding your medications, please ask your referring doctor or contact your nearest Southern Nuclear Imaging site before your appointment.
The other commonly performed heart scan is called a gated blood pool scan. This scan provides information on the actual contraction of the heart as it pumps the blood and also an Ejection Fraction can be obtained. It involves an injection of a solution which prepares the Red Blood Cell for second injection (20 minutes later) which is the radioactive tracer. ECG dots are placed on the chest and images of the blood pumping through the heart are taken.