PET Ammonia Cardiac Scan
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What is a PET ammonia cardiac scan?
A positron emission tomography (PET) ammonia cardiac scan is a simple way to take pictures of blood flow to your heart muscle when you are at rest and during a stress test.
What are some common uses of the PET scan?
PET scans are used most often to detect cancer and to check the effects of cancer treatments on the cancer. A scan is usually taken from the bottom of the skull through the pelvis.
PET scans of the heart can be used to check blood flow to the heart muscle and help evaluate signs of heart disease. PET scans of the heart can determine if heart muscle thought to be dead is just damaged or if it has improved in function.
Combined with other studies, PET scans allow us to tell the difference between dead heart muscle and heart muscle that would benefit from a procedure such as angioplasty or coronary artery bypass graft (CABG) surgery.
How do I prepare for a PET ammonia cardiac scan?
- Do not eat 6 hours prior to your study. It is OK to drink water. If you are scheduled for an afternoon study, you may have a very light breakfast before 7 a.m. on the day of the test.
- Do not eat or drink any caffeine or decaffeinated products (such as coffee, tea, herbal tea, chocolate, hot chocolate, cocoa, colas, and all other soft drinks) 24 hours before the study.
- Do not smoke cigarettes or cigars for at least 4 hours before the study.
- Talk to your doctor about your medications. Some medications should not be taken the day of the stress study. Taking certain medications on the day of the study can alter the results. Some medicines that affect test results include:
- Nitrates: sublingual NTG, Imdur, Isosorbide, Isordil, Isomo, ITG patch, and Nitrobid.
- Beta blockers: Atenolol, Metoprolol, Propanolol, Cavetilol, Nadalol, and Labetalol. - Wear comfortable clothing and dress warmly, as some scanner rooms may be cold. Do not wear clothes with metal (such as zippers) or jewelry on the day of the study.
- Bring imaging films from tests you have had done, such as PET, CT, or MRI, if possible. These can be on film or CD-ROM. Our doctors will use them to compare to your new PET scan.
- Make sure that your appointment time is convenient for you. The precise timing of this study is very important, so please plan to arrive on time. If you are more than 20 minutes late, your study may need to be rescheduled. The study takes about 2 hours.
What should I expect when I arrive?
When you arrive, a technologist will give you details about the study. An intravenous (IV) line will be started in one arm. Electrocardiogram (ECG) electrodes will be attached to your chest to monitor your heart during the study.
The Nuclear Medicine doctor will inject a small amount of radioactive tracer that will enable us to obtain pictures of your heart. There are no adverse or allergic reactions from the tracer.
Pictures of your heart will be obtained using the PET scanner. These images will show us the resting blood supply to your heart. When these images are done, you will then do the stress portion of the study.
A nurse practitioner or doctor will supervise the stress portion of your study. A medication that simulates the effect of exercise will be given through your IV. Several minutes after you receive this medication, a second small dose of radioactive tracer will be injected to allow us to take pictures of your heart when stressed. The stress imaging portion of the study takes about 30 minutes.
What will I feel during the study?
You may feel a little discomfort during the stress study. The most common feelings are feeling flushed, a tightness in the chest, or shortness of breath. A doctor or nurse practitioner will be monitoring you throughout the stress study. You will feel better before you leave. The radioactivity is gone within a day. There are no special instructions after the study.
