Exercise Stress Test with Myocardial Perfusion Imaging

Other Names: Nuclear Stress Test; Isotope Stress Test; Thallium; Myoview

Why is a Nuclear Stress Test ordered?

It is ordered for patients with symptoms or signs that are suggestive of coronary artery disease, or patients with significant risk factors for coronary artery disease.  It can also be used to evaluate exercise tolerance when patients have unexplained fatigue and shortness of breath, to evaluate blood pressure response to exercise in patients with borderline hypertension or to look for exercise-induced serious irregular heart beats.

What does a Nuclear Stress Test do?

It is designed to screen for the presence of coronary artery disease. Coronary artery disease is caused by inadequate blood supply to the heart, usually due to blocked arteries. In general terms, the tests looks for blockages in the arteries of the heart.

What is the Nuclear Stress Test procedure like?

An IV will be placed in a vein in your arm for the administration of the radioactive tracer. The IV will be removed before you leave. The test involves an injection of a small amount of a clear radioactive liquid called Myoview which circulates in the bloodstream and shows if your heart muscle is receiving adequate blood supply under stress and rest conditions.

Pictures of your heart will be taken by a nuclear camera while at rest and after exercising. You lie down with you arm over your head for about 15 minutes each time you are on the camera.

You will be asked to walk on a treadmill in order to increase your heart rate and place physical stress on your heart. The pace on the treadmill starts out very slowly and increases mildly every 3 minutes. The treadmill also slopes up gradually every 3 minutes. Most people walk between 6-12 minutes on the treadmill. Most people do not have to run on the treadmill, only walk.

What if I need to cancel my Nuclear Stress Test?

The radioactive material is ordered especially for you. If you are unable to keep your appointment for any reason, please call 24 hours in advance. If you do not notify us 24 hours in advance, we may have to bill you for the radioactive material.

What preparation do I need?

Pregnancy: If you are pregnant DO NOT TAKE THE TEST. If you are pregnant or suspect you may be, notify your doctor before taking the test.

Breastfeeding: You cannot breastfeed for 24 hours after receiving the radioactive agent. You will have to pump breast milk and discard it for those 24 hours.

Fasting: You may eat a very light breakfast (juice and toast) 4 hours prior to your test. Do not drink regular or decaffeinated coffee, tea, soda or any beverage containing chocolate twelve (12) hours prior to your scheduled appointment time.

You are encouraged to drink plenty of water.

  • If you are insulin dependant or take pills for your diabetes, you may eat a small breakfast - enough to take your insulin injection or to take your pills without a reaction from having low blood sugar.
  • Please bring a snack with you to have following the exercise portion of the test.
  • Please bring a sweater as it is very cold in our stress area.

The Nuclear Stress Test will take approximately 4 - 6 hours to complete. Please plan accordingly.

Medications: Do NOT take the following medications for 24 hours before the test:

  • Nadolol
  • Lopressor/Metoprolol Tart
  • Toprol XL/Metoprolol Succ
  • Sectral/Acebutolol
  • Tenormin/Atenolol
  • Kerlone/Betaxolol Hcl
  • Normodyne/Trandate
  • Calan/Verapamil
  • Tekturna
  • Inderal/Propranolol Hcl
  • Cardizem/Diltiazem
  • Corgard
  • Theodur
  • Visken/Pindolol
  • Blocadren/Timolol Maleate
  • Levatol/Penbutolol Sulfate
  • Coreg/Carvedolol

Please bring a list of your current medications with you.

Dress Attire: Please wear a button-down shirt that does not contain any metal buttons or zippers, or any other metal objects (this includes bras with metal under wires). Wear comfortable, secure pair of shoes suitable for walking on a treadmill. Please DO NOT wear sandals or backless shoes.

 DO NOT smoke any cigarettes the day of the test.

What can the Nuclear Stress Test test show?

If the test is normal during both exercise and rest, then blood flow through the coronary arteries is normal. The coronary arteries supply blood to the heart muscle.

If the test shows that perfusion (blood flow) is normal during rest but not during exercise (a perfusion defect), then the heart isn't getting enough blood when it must work harder than normal. This may be due to a blockage in one or more coronary arteries.

If the test is abnormal during both exercise and rest, there's limited blood flow to that part of the heart at all times. This part of the heart may be dead from a prior heart attack. It has become scar tissue.

What is the reliability of the Nuclear Stress Test test?

If a patient is able to achieve the target heart rate and if good quality images are obtained, an isotope treadmill stress test is capable of diagnosing important disease in approximately 80% of patients with coronary artery disease. Approximately 10% of patients may have a "false-positive" test (when the result is falsely abnormal in a patient without coronary artery disease).

When will I know the results of my Nuclear Stress Test?

If the test is markedly abnormal, the physician will speak with before you leave; otherwise, you will have a follow-up appointment within two weeks to discuss the results.