Nuclear Stress Test

A nuclear stress test is a diagnostic test used to examine the anatomy and function of the heart. Coronary arteries are best evaluated by determining the changes in blood flow to the heart due to exercising, because your heart has to work harder than normal. At CDI, we offer treadmill and medication-induced (Adenosine or Dobutamine) nuclear stress testing. In all cases, the purpose is to increase the workload being placed on your heart to check its function.

Exam preparation

A CDI representative will call you prior to your appointment to provide special preparation instructions, and to review health and insurance information.
Continue to take your usual medications with a sip of water, unless instructed otherwise by your doctor or nurse.
Diabetics who use insulin or glucose lowering agents may need to adjust their dosage – please check with your physician if you are not sure.
Wear comfortable clothes and walking shoes.
Please notify a member of CDI’s staff if you are nursing or if there is a chance you may be pregnant.
Please arrive 15 minutes early to verify your registration.

During the exam – what to expect

You will be asked to remove clothing above the waist; you will be provided a gown.
An I.V. will be started in your arm and a small dose of radioactive solution will be injected.
You will lie on a scanning table and a special camera (gamma camera) will be positioned close to your chest to take pictures of your heart. This part of the test evaluates blood flow to your heart muscle at rest and takes approximately 20 minutes.
Electrocardiogram (EKG) patches will be placed on your chest. For men, shaving the chest may be required.
A blood pressure cuff will be placed on your arm so that you can be monitored before, during and after stress.
Depending on the type of exam your doctor ordered, you will either be exercising several minutes on a treadmill or you will be injected with a prescribed medication (Adenosine or Dobutamine) over several minutes.
Your blood pressure will be checked intermittently. Tell the technologist if you experience any symptoms such as chest pain, dizziness, weakness, lightheaded, or leg fatigue.
Near the end of the exercise or injection period, and depending on your blood pressure or heart rate, the technologist will inject a radioactive contrast (dye) agent. The injected substance will travel throughout your body and will concentrate in your heart.
After stopping “exercise,” you will continue to be monitored until your heart rate and blood pressure return to pre-exercise/injection levels.
Finally, you will lie on an examining table and a gamma camera will obtain images of your heart, where the radioactive contrast agent will have collected.
Comparison of the exercising and resting images is done to determine whether coronary blood flow has changed once you have rested and to check for coronary artery disease.
The entire exam will take approximately one and a half hours.

After the exam – what to expect

A cardiologist or specially trained radiologist will review your images and prepares a diagnostic report to share with your doctor.
Your doctor will consider this information in context of your overall care, and talk with you about the results.

Possible side effects

There are no reports of allergic reactions or side effects related to injection of the radioactive agent.

If you have additional questions about your appointment or our services, check out our Frequently Asked Questions or contact your local CDI center.