Norfolk County Cardiologist Association

A Stress Test with Cardiolite


WHAT IS IT?

The heart receives life-giving blood from vessels called coronary arteries. If these arteries become partially blocked or narrowed by the accumulation of fatty materials, the heart may not receive the blood it needs to function properly. This narrowing of coronary arteries is called coronary atherosclerosis or, more commonly, coronary artery disease (CAD).

The stress exam with Cardiolite (Kit for the Preparation of Technetium Tc99m Sestamibi for Injection) is a diagnostic nuclear medicine exam used to determine if the heart muscle is getting the blood supply it needs.

As CAD progresses, the heart muscle may not receive enough blood when under stress (for example, when exercising). This often results in chest pain called angina pectoris. On the other hand, there may be no outward physical signs of the disease. If CAD is limiting blood flow to a part of your heart, the stress exam with Cardiolite may be useful in detecting the presence and significance of CAD.

This exam usually consists of two parts, rest and stress:

1. Cardiolite will be administered by injection while you are at rest, and a special camera will take pictures of your heart.
2. Cardiolite will be administered to you one other time by an injection during exercise (the "stress" portion of the test), and additional pictures will be taken of your heart.

This allows the physician to compare the amount of blood flowing through the heart muscle during stress and at rest. The pictures are generally taken about one-half hour or longer after Cardiolite is administered. The physician or technologist will inform you if the exercise or rest portion of the study will be done first, and whether the entire exam can be completed in 1 day or on 2 separate days.

Exercise and pharmacolgic stress testing should be performed only under the supervision of a qualified physician. Cardiolite has been rarely associated with acute severe allergic events of angioedema and urticaria. The most frequently reported adverse events include headache, chest pain/angina, ST segment changes on EKG, nausea, and abnormal taste and smell.

PREPARING FOR THE TEST

A nuclear medicine exam with Cardiolite (Kit for the Preparation of Technetium Tc99m Sestamibi for Injection) involves the injection of a small amount of a radioactive material, which is cleared from you body by natural processes. The amount of radiation you will be exposed to is comparable to that from an X-ray or CAT (CT) scan. Millions of nuclear medicine exams of various types are performed each year.

WHAT SHOULD I DO BEFORE THE TEST?

1. You may be asked not to eat or drink 3 or 4 hours prior to the test. This will prevent the possibility of nauseas, which may accompany vigorous exercise after eating. In addition, the pictures of your heart are more clear when the stomach is not full.

2. Your physician may decide to temporarily discontinue certain heart medications prior to the stress exam. These are discontinued because some heart medications may interfere with the accuracy and effectiveness of the exam

3. A hospital gown may be provided on the day of the test. Slacks or shorts are preferred for the exercise portion of the exam. You should wear comfortable footwear appropriate for brisk exercise on a treadmill (a moving belt you walk on) or stationary bicycle. You will work hard during the test and comfortable clothing will make it easier for you.

Prior to the stress exam, you may be asked to sign a consent form. Please read the form carefully. If you have any questions about the procedure, do not hesitate to ask the person supervising the test. He or she can explain the entire procedure before it begins.

WHAT WILL HAPPEN TO ME?

Several small pads called electrodes will be placed on your chest. These pads will be connected to an electrocardiograph (ECG) monitor so that your heart rhythm can be watched closely throughout the exercise portion of the test. An intravenous (IV) line will be placed in your arm. This line will be used to inject Cardiolite into your bloodstream during exercise. The IV line will be removed soon after the test is completed.

WHAT HAPPENS DURING THE TEST?

You will exercise by walking on a moving belt, called a treadmill, or by pedaling a stationary bicycle. If you walk on a treadmill, it will move very slowly at first, then increase in speed. If you pedal a stationary bicycle, it will feel easy to pedal at first, then it will gradually get harder. As you exercise longer and harder, your heart rate and blood pressure will rise. This is normal and they will be monitored along with your ECG.

You will be encouraged to continually exercise throughout the stress exam. If you experience any unusual symptoms at any time, such as lightheadedness, immediately tell the individual monitoring the test. Adjustments will be made to the exercise test, depending on your symptoms, blood pressure, ECG, or degree of fatigue.

The technologist will begin taking pictures following your exercise. This is called imaging. For this portion of the exam, you will be asked to lie flat on your back on an imaging table. Imaging begins with the camera positioned close to your chest.

For the resting portion of the exam, an electrocardiograph may not be needed. Cardiolite will be injected and, about one-half hour or longer after the injection, the technologist will begin taking picture of your heart. The camera will be placed close to your chest while you are lying flat on the imaging table.

WHAT YOU SHOULD KNOW

During imaging, the camera will take pictures at various angles. It will take 15-30 minutes to complete the imaging portion of the exam. It is important for you to remain very still while the images are being taken.

Following completion of the exam, the doctor will discuss the results of the test you're your own physician and submit a written report. Your physician will then explain the test results and their implications to you.

PRECAUTIONARY INFORMATION

The Cardiolite administered during this stress exam contains a small amount of radioactivity. The amount of radiation you will be exposed to is comparable to that from an X-ray or CAT (CT) scan.

If you are pregnant, suspect you may be, or are a nursing mother, discuss this with your doctor before undergoing the procedure.

Adverse patient reaction to Cardiolite is rare. You may briefly notice a metallic taste a few seconds after injection has occurred. Other side effects have occurred rarely.

This brochure is not a substitute for a discussion with your doctor. Please consult your doctor for more information on the procedure and medication described in this brochure. This is not intended to provide complete information about your stress test or Cardiolite.