Dobutamine Cardiac Stress Imaging
Your heart receives blood from vessels called coronary arteries. The Dobutamine Cardiac Stress Imaging test is designed to determine if there are any blockages in your coronary arteries, how severe they may be, and if there has been any damage to your heart from blockages in your arteries.
Is the Test Safe?
There are no known risks or serious side effects from the small amount of radioactive compound that you will receive. Serious side effects from this test are extremely rare. You will be taken care of and watched very closely by an experienced team of medical personnel, with a cardiologist readily available.
How Will This Test Help Me and My Doctor?
After the test results are reviewed by a team of physicians, a written report will be mailed to your doctor. The test will tell your doctor if there are problems with the blood flow to your heart, and help to guide any further tests or treatments. Your doctor will explain these to you at the time of your next contact with him or her.
PREPARATION: What You Need to Do For This Test
- Please review with your doctor any heart or blood pressure medications that you are taking. Some of these medications may need to be adjusted for this test, depending on what your doctor wants to know.
- If there is a possibility of you being pregnant or you are breast-feeding, please let your doctor and our staff know before starting this exam.
- If you have diabetes, please call your doctor for instructions.
- Please bring any medications that you may need that day as you can take them when the test is completed.
- Please do not eat or drink anything for 4-6 hours before the test, except for medications approved by your doctor with a small sip of water. It is important that you do not take any products which contain caffeine such as coffee, tea, caffeinated soft drinks, chocolate, etc.
- Wear comfortable clothing.
- Please do not apply any powder or lotion to your skin on the day of the test.
What is the Procedure for the Administration of the Dobutamine?
Several small pads called electrodes will be put on your chest. The electrodes allow us to closely watch your heart rate and electrocardiogram during the test.
An intravenous line (IV) will be placed in your arm so that we can inject the radioisotope compound (thallium or sestamibi) and the necessary medications into your blood stream.
Dobutamine will be infused through the IV at slowly increasing strengths. Dobutamine is given in order to increase the strength and speed of your heart beat, and you may feel this as a sensation of palpitations. Your heart rate, rhythm, and blood pressure will be monitored very closely. You will be asked to report symptoms, if any, that you may have.
At the maximum dobutamine infusion, you will receive through the IV an injection of the radioisotope compound. If need be, a small dose of a medication called atropine will also be given to further increase your heart rate.
Approximately 5 to 30 minutes later, you will be asked to lie on your back on a special table, with your arms extended over your head on a specially made support. We will take pictures of your heart with a scanning camera for about 30 minutes.
What Other Images Are Taken?
For this portion of the test, you may or may not need to have a separate injection of the radioisotope compound. This may be done before or after the exercise, usually on the same day, but sometimes on a separate day. You will again be asked to lie on the imaging table for about 25-30 minutes so that we can take pictures of your heart.
What Happens After the Test?
When the exam is completed, the nuclear medicine physician will review your images, prepare a written report and discuss the results with your doctor. Your doctor will then explain the test results to you and discuss what further procedures, if any, are needed.
What Other Information Should I Know?
- The amount of radiation you will receive during the test is no more than what you would receive from similar x-ray procedures.
- Be sure to tell your doctor if you are pregnant, think that you are pregnant or are a nursing mother.
- The tracer you are given remains in your body for a short time and is cleared from the body through natural bodily functions. Drinking plenty of fluids will help eliminate the material more quickly.
- You should be able to resume your daily activities after the test.