Cardiac PET Imaging
A cardiac Positron Emission Tomography (PET) scan is used by doctors to evaluate the health of your heart. The results of this scan will help your doctor determine if you should have follow-up treatment. If you are already being treated for a heart-related condition, the results of this exam can also be used to help your doctor manage your
Knowing what to expect can help you feel more relaxed during the procedure. Most cardiac PET scans are completed in less than one hour; however, a longer procedure should not be cause for concern. No caffeine products 48 hours prior to your test. This includes tea, coffee (even decaffeinated), chocolate, soda, or energy drinks.
The following are general guidelines to follow before your scan:
- Consult your physician about taking your medications before the exam
- Stop smoking before the test.
- Do not eat 4 hours before your scan.
- Do not drink 2-4 hours before the start of the test. Clear liquids are OK.
- Wear a comfortable two-piece outfit to the exam
- Trained medical personnel will be with you throughout the exam
- You will be asked questions about your medical history.
- An IV line will be placed in your arm to allow administration of medication.
- Small pads (electrodes) will be placed on your chest so that the medical team can monitor your heart throughout the study.
- You will be asked to lie on a scanning table on your back during your PET scan.
- Your blood pressure will be monitored remotely during your scan procedure with an automatic blood pressure cuff.
- A small amount of radiophannaceutical will be given through your JV line that allows the PET scanner to take pictures of your heart.
- The amount of radiation exposure you receive is low and considered safe by the National Council on Radiation Protection and Measurements.
- The PET scanner will take pictures of your heart in the rest and stress phases, each imaging phase will last up to 10 minutes.
- The stress phase (second pan) of the exam is usually performed with a pharmaceutical that makes the arteries of your heart respond as if they were exercising.
- The pharmaceutical is given through the IV line while an electrocardiogram (ECG) is performed to monitor your heart.
- Please let the technologist know if you have any symptoms during the test to give them a better assessment of your condition.
- You may experience chest pain, palpitations, headaches, shortness of breath, or a flushing feeling during the test. However, these symptoms will subside within a couple of minutes.
Your test is finished when both rest and stress scans have been completed. Be sure to ask the technologist about returning to your normal diet and routine. Most patients return to their normal routines immediately after the test. If you have any questions, feel free to ask the technologist before leaving the scanning room.
The scan information will be processed by the technologist and given to your own physician or an interpreting physician for review. A written medical report will then be generated.
Before you go home, be sure to make an appointment with your doctor’s office for a follow-up visit to go over your results.
Cardiac SPECT Imaging
What is a Cardiac SPECT Scan? A Nuclear SPECT scan (Single Photon Emission Computerized Tomography) is a 3D scan of your heart. A small, safe amount of a radioactive drug called a tracer-is used to determine how well your arteries can carry adequate amounts of blood flow to your heart. The process of your heart filling with the tracer is called perfusion. Arteries that are blocked or closed can cause a lack of blood flow to the heart, which will appear as an absence of perfusion in the cardiac muscle. This indicates a problem or defect in your scan.
One scan is taken with your body in a rest condition and one in a stress condition. If your scan is abnormal or has a defect, these two scans will show your doctor whether there is the presence of either an infarct or ischemia.
- Infarct: A defect present in both the rest and stress scans.
- Ischemia: No defect in the rest scan, however, there is a defect in the stress scan.
Knowing what to expect can help you feel more relaxed during the procedure. The stress portion of your exam may be performed on a treadmill or with the use of medicine prescribed by your physician. The entire test will take approximately 2-3 hours.
No caffeine 24 hours prior to your test.
This includes tea, coffee (even decaffeinated), chocolate, soda, or energy drinks.
- When you schedule your test, be sure to mention all medications you are taking. Be sure to ask if you should stop any of them the day of the test (Beta blockers).
- Stop smoking before the test.
- Do not eat 2-4 hours before the start of the test. Clear liquids are OK. No caffeine.
- Wear something comfortable the day of the test such as a two piece outfit with walking shoes for exercise.
ln 30-45 minutes after the initial injection of the tracer, the scan of your hea1t at rest will be performed taking about 10 minutes. At 30-60 minutes after the stress injection, you will be scanned again giving the doctor images of your heart after stress.
During the actual test:
- An IV (intravenous) line will be started in your arm.
- An initial tracer (Cardiolite or Thallium) will be given through the IV line.
- 30-45 minutes later you may be attached to an EKG and have your rest scan. This will take about 10 minutes. In order to have the clearest images please remain as still as possible once the technologist has started the scan.
- Next, you will be taken into the treadmill room for the exercise, or stress, portion of the exam. You will be asked to walk or exercise for a few minutes. If you are unable to achieve a high level of exercise, the doctor will prescribe a medicine that will allow the blood to flow to your heart as if you were exercising.
- During this stress portion of the exam, you will be attached to an EKG and a blood pressure monitor. A second tracer will be given through the IV line in for the stress scan.
- 30-60 minutes later (the technologist will appoint you a time) you will have your second, or stress, scan. This will also take about 10 minutes. Again, please remain as still as possible once the technologist has started.
Your test is finished when both rest and stress scans have been completed. Be sure to ask the technologist about returning to your normal diet and routine. Most patients return to their normal routines immediately after the test. Be sure to read under “Your Test Results” about important follow-up information.