Adenosine Dual Isotope Study
What is an Adenosine Dual Isotope Study?
This procedure is used to evaluate the adequacy of the blood supply to the heart muscle during periods of exercise (stress) and rest. Adenosine is a medication used to chemically increase blood flow as with exercise.
This test is most commonly used in people who need stress testing but have difficulty walking, either due to blood-vessel problems, arthritis, or loss of a limb. It can be used to evaluate different types of symptoms one may be having (chest or arm pain, palpitations, shortness of breath, dizziness, or fatigue), or to evaluate a person without symptoms who may have silent heart disease, or to assess one’s risk for an operative procedure.
Thallium-201 and Technetium 99-m Cardiolite are radioactive tracers used to examine blood flow in the coronary arteries. The level of radioactivity is extremely low and has no side effects. The arteries that supply blood to the heart muscle can become clogged or narrowed from the buildup of plaque (atherosclerosis or coronary artery disease). The tracer images allow us to see the heart muscle that is receiving blood supply. If atherosclerosis is present, the tracer images of your heart will give us an idea which arteries are involved and the amount of heart muscle that is at risk for problems.
Upon arrival at our office:
A small intravenous catheter will be placed in your arm or hand to administer the radioactive tracers and the Adenosine. The technologist will inject the first radioactive tracer into the IV line.
You will be asked to lie flat on your back on an imaging table with both arms above your head. The camera will move slowly around your chest for a period of 20 minutes.
You will then be taken to the treadmill room in preparation for the Adenosine infusion, where your chest will be prepared for the placement of small plastic pads for monitoring and obtaining a baseline electrocardiogram (EKG). Your heart rate, EKG, and blood pressure will be monitored during the procedure.
You will be given the Adenosine medicine gradually over a four-minute period while you are walking very slowly on the treadmill. (If you are unable to walk on the treadmill, the infusion will be given while you are sitting or lying down.) During the infusion of the Adenosine, the second radioactive tracer, Cardiolite, will be given. Occasionally, Adenosine will cause side effects including chest pressure/tightness, mild shortness of breath, flushing, headache, and possibly nausea. These side effects go away very quickly once the medication is stopped.
Upon completion of the Adenosine portion of the test, the EKG pads and IV line will be removed. You will have approximately a one-hour wait prior to the second set of pictures. (During that waiting period, you may have a snack and take your medications.)
After the second imaging session of 20 minutes, you may resume your regular diet and routine.
Preparations for the Test:
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No food or drink four (4) hours prior to your appointment.
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Do not eat or drink anything containing caffeine 24 hours prior to your appointment. This includes products labeled “decaffeinated” and all forms of chocolate. Commonly used drugs containing caffeine are Anacin, Excedrin, Darvon, Midol, and cold remedies.
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Wear comfortable clothing and shoes suitable for walking. No heels or sandals. Do not wear a dress, full slip, or tight jeans.
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Plan on spending 3-4 hours for the test. You may have short breaks between portions of the test. You may bring a snack with you (e.g., crackers, fruit, or sandwich). After your stress test, you will be instructed when you may eat and drink.
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If you are on medications for bronchospastic lung disease, asthma, COPD, or emphysema, please bring medications with you and notify the technologist immediately.
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If you have diabetes, you may take ½ your dose of insulin/medicine with a small meal 4 hours before your test or bring your diabetes medication with you.
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If your are in atrial fibrillation or atrial flutter, remain on ALL of your medications.
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If you are pregnant, may possibly be pregnant, or are a nursing mother, discuss this with your physician prior to your exam.
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If there are any questions regarding your medications or the test, call our office at 352-264-2500 ext 318.
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A 24 hour notice of cancellation is required. Without proper notification, you will be charged a fee up to $125.00 for the cost of all pre-ordered medication.
Do not take these medications the day before the test and the morning of your test:
- Acebutolol (Sectral)
- Atenolol (Tenormin, Tenoretic)
- Bisoprolol (Zebeta, Ziac)
- Carvedilol (Coreg)
- Cialis
- Diltiazem (Cardizem CD, Cardizem SR, Cartia XT, Dilacor XR, Tiazac)
- Felodipine (Plendil)
- Labetalol (Trandate, Normodyne)
- Levitra
- Metoprolol (Lopressor)
- Nadolol (Corgard, Corzide)
- Nifedipine (Adalat CC, Procardia, Procardia XL)
- Nisoldipine (Sular)
- Penbutolol (Levatol)
- Pindolol (Visken)
- Propranolol (Inderal, Inderide LA)
- Sotalol (Betapace) *Discuss with ordering doctor
- Timolol (Blocadren, Timolide)
- Viagra
- Verapamil (Calan, Isoptin, Verelan)
Do not take the following medications the night before your test:
- Dilatrate
- Imdur
- Ismo
- Isordil
- Nitro-Bid
- Nitroglycerin patch
Bring your blood pressure medications and inhalers (if applicable) with you the day of your test.
Take all other medicines that are not listed above with a small amount of water the morning of your test.
Test Results:
If a Cardiology Associates of Gainesville (CAG) physician, nurse practitioner or physician’s assistant ordered your test, you should receive your test results either by telephone or by mail in approximately 7 business days. After that time, if you have not received your test results, you may call our office at 352-264-2500 ext. 499 to reach our patient message center. You will need to leave your name, telephone number, date and type of testing and the ordering physician’s name. You will receive a call back within 24 hours with an update regarding your test results.