A positron emission tomography (PET) scan of the heart is an imaging test that uses specialized dye containing radioactive tracers to detect whether your heart is receiving enough blood or if there is any damage to the heart muscle. A PET scan allows your doctor to see which areas of your heart may be injured or diseased. The imaging is performed after a pharmacological (medication-based) stress test. This is typically an outpatient procedure and does not have any long-term effects.
The PET scanner is a large machine with a round, donut-shaped hole in the middle, similar to an MRI scanner. You will be asked to lie down in the center of the scanner for imaging. The enclosure is somewhat small, so let your provider know beforehand if you tend to experience claustrophobia.
This procedure typically takes about one hour to complete from start to finish. When you arrive, you’ll be asked to change into a hospital gown and empty your bladder for testing. A health care specialist will then inject the radioactive tracer into your arm or hand. You may feel a cold sensation moving up your arm. The stress test with the medication lasts one to four minutes and is performed while you’re in the scanner. You’re typically in the scanner for a maximum of 30 minutes.
A PET scan is the most accurate test available for observing the heart blood flow within the smallest blood vessels supplying the heart muscle. It can also provide an accurate assessment of the condition of the cardiac muscle after a heart attack and in patients with heart failure.
While a PET scan does use radioactive tracers, the exposure is minimal and is the lowest among all cardiac testing that uses radiation, including a standard nuclear stress test. Other than the potential of slight injection pain, soreness from the exam table, and feelings of discomfort if you’re claustrophobic, there are no side effects of a PET scan.
Both cardiac PET scans and echocardiograms are used to help your doctor evaluate the blood flow to the heart; however, they are very different tests. Echocardiograms use high-frequency sound waves to create an outline of the heart’s valves and chambers. This test helps your doctor evaluate the pumping action of the heart. A PET scan is more accurate for abnormalities in the blood flow all the way down to the capillaries of the heart muscle.
Both the cardiac PET scan and nuclear stress test use radioactive material to evaluate the heart. Typically, a PET scan is considered more accurate than a nuclear test because the soft tissue in front of the heart can sometimes distort the nuclear images. However, since PET is combined with CT, the image quality is extremely precise. Cardiac PET is also able to diagnose conditions like cardiac sarcoidosis that cannot be done with a standard nuclear scan.
AHN Cardiovascular Institute was the first PET-CT program operating in Pittsburgh and is only one of two programs in the surrounding tri-state area. This sophisticated imaging technique can be combined with a standard pharmacological stress test to obtain accurate results about myocardial blood flow and viability.
PET/CT scans can be completed in one hour, and results are available the same day.