What is a Cardiac Nuclear Lexiscan Exercise Stress Test?
This test uses a radioactive material (isotope) that is injected into the bloodstream and allows the Nuclear Medicine technologist to take pictures of your heart. For patients who are unable to exercise, the nuclear imaging material may be combined with a medication called Lexiscan. The test will produce images/pictures that will help your doctor to determine if there is an area of your heart that is not receiving enough blood. The nuclear imaging material is not a "dye." It is widely used and has been shown to be safe.
How does the Lexiscan work on the heart?
The Lexiscan is injected into an intravenous (IV) line and produces a slight widening of the arteries. Arteries that are healthy will respond more to the Lexiscan than arteries that are diseased. The scan done following the infusion will show the areas of the heart that are supplied by healthy arteries and those with blockages or areas of possible disease.
What will the pictures show?
After the injection, the nuclear imaging material travels through the bloodstream to the heart. The nuclear imaging material gives off a small amount of radiation that can be seen with a special camera. The areas of the heart that are diseased (because of blocked or narrowed arteries) will not pick up as much nuclear material as those with healthy arteries. The computer will process the images to show areas of decreased blood flow, called "defects." The Cardiologist will analyze these pictures.
How is it done?
The test is done in two parts, resting and stress. The first part is done after an IV is started in your arm and the nuclear imaging material is injected into your vein. This will be allowed to circulate for 30 minutes, while you rest comfortably on a bed or in a chair.
Following this circulation time, the first scan will be done. For both scans, you will be asked to lie flat with your left arm above your head. This scan takes about 15 minutes. After completing this scan, the second part of the test will begin.
The second part of the test involves resting on a bed or chair or walking slowly on a treadmill, if you are able to, while the Lexiscan is injected through your IV. This will be followed by a second injection of nuclear imaging material. Once again, this imaging material will circulate for 30 minutes while you rest and then the final scan will be done under the same camera. You will be allowed to eat or drink during this wait. This scan time is about 15 minutes.
It is important that you lie still for each scan while the camera rotates around your chest. The two scans will help to determine if any defects or blockages are temporary, or if they are permanent as a result of earlier heart damage.
How do I prepare?
- Bring all of your signed doctors' orders and referrals with you.
- Bring a list of your medications with you.
- Do not eat or drink anything after midnight the night before.
*NO caffeine for 12 hours before your test and NO tobacco the day of the test.
- Notify your doctor if you have asthma or any chronic lung disease.
- Should I take my medicine on the day of the test?
CONSULT THE DOCTOR who ordered the test about your medications. Medications containing THEOPHYLLINE are very important to ask about. Medications containing THEOPHYLLINE are very important to ask about. Get specific instructions about medications for blood pressure and diabetes.
- Dress in comfortable clothing for the test.
How long does it take?
Allow 3-1/2 to 4 hours for the test
How will I get the results?
Results are generally available in about 48-72 hours. Contact the doctor who ordered the test to obtain the results.
PLEASE NOTE: If the results of your test need to be sent to a physician that does not practice at Doylestown Hospital, you will need to provide the doctor's full name, address and, if possible, FAX number. You may provide this information on the day of your visit or call 215-345-2231 Monday through Friday 8AM - 4:30PM.