Our UHN programs and services are among the most advanced in the world. We have grouped our physicians, staff, services and resources into 10 medical programs to meet the needs of our patients and help us make the most of our resources.
University Health Network is a health care and medical research organization in Toronto, Ontario, Canada. The scope of research and complexity of cases at UHN has made us a national and international source for discovery, education and patient care.
Our 10 medical programs are spread across eight hospital sites – Princess Margaret, Toronto General, Toronto Rehab’s five sites, Toronto Western – as well as our education programs through the Michener Institute of Education at UHN. Learn more about the services, programs and amenities offered at each location.
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Find out how to get to and around our nine locations — floor plans, parking, public transit, accessibility services, and shuttle information.
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Please bring with you a list of your current medications. This includes prescription medications, over-the-counter medications, vitamin or mineral supplements and herbal remedies.
DO NOT eat or drink caffeinated, decaffeinated or caffeine-free products (such as soda, chocolate, coffee, energy drinks, tea, or Tylenol #1, 2 or 3) for at least 48 hours before the test.
When you arrive at the
Nuclear Cardiology Lab, check in at the reception desk. Please have the following ready:
When you check in, the receptionist will give you a name band to wear. The technologist will call you when it is time for your test. You will be asked to change into a hospital gown. There are lockers for your clothes in the change area, but you should keep your valuables with you.
When you have finished changing, a technologist will take you into the room. They will explain the procedure and ask for your consent.
A technologist will first ask you questions about your medical history, do an
ECG and check your blood pressure and heart rate. Then you'll have 2 intravenous (IV) lines in your arm or hand. One will have an infusion of Adenosine for 6 minutes while we check your heart rate, ECG and blood pressure.
After 3 minutes, a needle of thallium (a radioactive tracer) will go into the second IV line.
The next step is to take pictures of your heart. You need to lie very still under a gamma camera with your arms above your head for 30 minutes.
Then you'll have a 2 to 3 hour break. You can only drink clear liquids while on your break.
When you return, we'll take pictures again of your heart, this time at rest. You'll need to lie very still again under the gamma camera – again with your arms above your head for 30 minutes. We have you keep still so that our pictures are clear. If you move, we may need to take more pictures.
Once the test is completed, the technologist uploads your results to your records. The physician/radiologist will write a report and send it to your doctor.
The technologist cannot give you the results during your visit.
Once the report is in your health record, your doctor can review it. You will get the results of the test from your doctor.
Your appointment will take about 4 to 5 hours. The first part of the adenosine thallium test will take 2 hours followed by a break and the second part will be 1 hour.
We do everything that we can to stay on time. Unfortunately, your appointment may be delayed by unforeseen circumstances. We recommend that you come prepared for delays.