Nuclear Medicine - STRESS REST

What is Myocardial Perfusion Imaging?

Myocardial perfusion imaging uses a radiopharmaceutical administered intravenously to monitor the movement of blood flow in the myocardium.  Perfusion imaging identifies areas of reduced blood flow associated with ischemia or scarring.


Assess the presence, location, extent and severity of myocardial perfusion abnormalities
Determine the significance of anatomic lesions detected by antiography
Detect viable ischemic myocardium

How do I prep for this procedure?

You will be in the department for 90 minutes to 2 hours.  Nuclear Medicine technologists or Radiology nurse will start a hep-loc so two isotopes can be injected.  Images of the heart at REST will be taken 5-10 minutes post first injection.  During the STRESS stage a second isotope will be injected and imaging will begin immediately to one hour after stress depending on bowel activity.  You may be sent to eat a good meal or asked to eat cheese and drink milk to help eliminate some bowel activity.

  • Rest injected
    • Patient should be fasting for at least 4 hours (preferably for 12 hours). No caffeine. Consult your cardiologist about wheelchairs and cardiac medications.
  • Exercise Stress
    • Graded exercise stress is usually performed with a treadmill or bicycle ergometer with continuous patient monitoring. No caffeine.  Fasting for a minimum of 4 hours before the stress study is recommended.
  • Pharmacologic stress

Two types of pharmacologic stress are useful to evaluate myocardial perfusion:

  • Vasodilator stress agents may be administered to create coronary adenosine.  Caffeine-containing beverages should be taken which interferes with the coronary hyperemia.
  • Ino/chronotropic adrenegic agents (i.e. dobutamine) are to be administered to increase myocardial oxygen demand. No caffeine is to be taken prior to the exam