Once a physician has written an order for a Cardiolite or Thallium study, several things need to happen before the study can be performed.  First, the patient has to be scheduled with our scheduling department on a day that is convenient for the patient.  Second, the patient has to carefully follow the instructions given to him/her on how to take medications for this study.  Third, the patient cannot eat anything for at least six hours before the study or drink any caffeinated products for at least 12 hours prior to the study.

Upon arrival to the Heart Institute, the patient is escorted to the Nuclear Cardiology Laboratory, where a nuclear medicine technologist explains the nuclear medicine study and answers any questions related to the study.   Next, the technologist places a small venous catheter in the patient's vein.  The technologist injects the patient with a dose of radioactive material.  After the injection, the patient is asked to wait one to two hours to allow for normal biophysiological events to occur.

After the waiting period, the patient is escorted back to the nuclear lab where he/she is placed on an imaging table.  The patient will be imaged using the gamma camera, which detects where the radiopharmaceutical is in the heart muscle.  The imaging takes approximately 12-15 minutes.  The patient is then escorted to another area where a registered nurse will explain the stress test and answer any questions regarding the test.

Physicians can order the stress portion of the test to be performed one of two ways:   mechanically, using a treadmill,  or chemically, using one of several stress drugs.   A cardiologist is present while the patient is being stressed.

During the treadmill portion, the cardiologist exercises the patient until his/her heart rate reaches a certain level or until the supervising physician stops the test.  When the patient's heart reaches a certain level, the patient is injected with another dose of radioactive material and asked to walk for one minute after the injection.

When the physician orders a drug to be given, the test is usually performed while the patient is lying down.  The stress drug is given via a catheter already in place.  A drug called adenosine is usually the drug of choice and is given over a four minute period.  A drug called dobutamine is used in certain situations and is also given over several minutes.  A dose of radioactive material is given during the infusion of the drug.

Patients undergoing stress testing -- whether mechanical or chemical -- are monitored before, during and after the test.

The patient is asked to rest before the last images are done.  After the patient has rested, he/she will be escorted back to the gamma camera and imaged for a second time.   The gamma camera then detects where the blood flowed to the heart muscle at stress.   This last procedure takes approximately 12-15 minutes.

Once the imaging is complete, the rest and stress data will be processed and compared to a normal database.  A specially trained cardiologist will compare the blood flow pattern at stress to the blood pattern at rest and determine if the patterns are the same.   The information the referring physician receives from this study helps in the diagnosis and treatment of certain heart diseases.

Patient Preparation
  1)  Bring all medications
  2)  Wear comfortable clothes
  3)  Do not eat anything for at least 6 hours prior to the
        study
  4)  Do not drink anything except water for at least 12 hours
        prior to the study
  5)  Be prepared to stay 3 to 4 hours

Please tell the technologist or nurse if:
  1)  You are pregnant or think you may be
  2)  You are breastfeeding
  3)  You have asthma
  4)  You have had another nuclear medicine study within
        the last month

*Sometimes certain situations require that the patient come back another day for another part of the study.