There are two parts to a myocardial perfusion study, a resting scan and a stress (exercise) scan. There is a 2-3 hour interval between the two scans, so you will need to allow most of the day for this study.
THE RESTING SCAN:
You will receive a small dose of a radiopharmaceutical (radioactive) tracer by intravenous (IV) injection. The first scan will be performed after about 40 minutes, when the tracer has accumulated in the heart muscle. You will lie flat on the scanning table while the camera records images at various positions around your chest. This scan takes about 30 minutes to complete.
THE STRESS SCAN:
Before the scan you will have ECG leads connected and an IV line inserted in your arm. You will then exercise, usually by walking on a treadmill while the changes in your heart rate and blood pressure are monitored. At near peak exercise the tracer is injected through the IV line; ideally you should continue to exercise for about a minute after the tracer injection. Once the exercise is over there is a 30-minute rest before the stress heart images are recorded in a similar manner to those recorded in the rest scan. If you are unable to exercise the stress test can be mimicked by infusion of a drug instead (similar to the dobutamine echo).
For information about preparation for the scan, temporarily stopping medications etc. contact New Zealand Medical Imaging. If you are pregnant, suspect you may be pregnant, or are a nursing mother, discuss this with your doctor before undergoing the test. For more general information about myocardial perfusion scanning you can access the - American Society of Nuclear Cardiology website.