A pharmacological stress test with Myocardial Perfusion Imaging (MPI) is a type of stress test that can be done for those individuals unable to walk on a treadmill. This test uses a short-lived radioactive material, which along with computer imaging will help highlight any severely diseased blood vessels that may be causing diminished blood flow to your heart.
This test aids your physician in determining whether you have heart disease, or a heart-related cause of symptoms, such as shortness of breath or chest or upper back pain.
- An intravenous (IV) line will be started to allow the technician to inject Cardiolite (the radioactive material). Cardiolite is a radioactive tracer used for computer imaging of your heart that will be taken later. Cardiolite is not a drug or
dye and causes no known side effects or symptoms. After about 45-60 minutes, you will be set up under the imaging camera and asked to lie on your back with your arms over your head for 15 - 20 minutes.
- The second part of your test is the “stress” portion. An exercise technician will place electrodes (small adhesive patches) on your chest, wrists and ankles. Lead wires will then be connected to the electrodes.
- You will lie down on your back for approximately 20 - 45 minutes, as you are not required to exercise for this test. An electrocardiogram (EKG) and a blood pressure will be obtained to ensure there are no significant abnormalities that would prevent
your test from being done.
- The pharmacological agent (usually Persantine or Lexiscan) will be administered for four minutes through the IV line. This medicine allows the blood vessels to dilate (increase in size).
- There are potential side effects from this medication, such as a warm, flushed feeling, headache, nausea, or chest pain. If you experience any of these symptoms a medicine called Aminophylline may be given through your IV to reverse the symptoms.
- After the Persantine or Lexiscan is injected, a second injection of Cardiolite will be given through your IV.
- Your responsibility is to inform the test technician of any developing symptoms (headache, chest pain, dizziness, lightheadedness, shortness of breath). If there are any abnormal responses, the test can be stopped and/or Aminophylline may be given.
- A short recovery period is then done with continued heart rate, EKG and periodic blood pressure monitoring. As soon as these measurements are close to your initial or resting values, you will be disconnected from the monitor.
- Approximately one hour after the infusion of the Persantine or Lexiscan and injection of Cardiolite, you will be taken to the Nuclear Medicine department for a second series of pictures of your heart. You will lie on your back with your arms over
your head for 15 - 20 minutes. You may also be asked to lie on your stomach for an additional 15 - 20 minutes for a second set of pictures.
- A cardiologist and nuclear medicine physician will review the test and interpret it for your follow-up visit or for forwarding to your referring physician.
Allow approximately 3 - 4 hours for your procedure as there are significant wait times required between each step of the test. The wait time is necessary to ensure good images under the camera.