Gated Blood Pool Imaging - Diagnostic test for heart diseases

Gated blood pool imaging creates pictures which provide information about your heart, including: size, shape, wall motion characteristics, and overall pumping efficiency . The pictures can be used to determine your "ejection fraction", which is the percentage of blood pumped out of a filled ventricle (lower heart chamber) with each beat.

This imaging study may be performed while you are at rest or while you exercise. Both resting and exercise imaging require two intravenous injections. The first injection prepares the red blood cells; the second injection consists of a radioactive tracer (technetium), which labels the red cells. This small amount of tracer enables the doctor to see pictures of your heart.

This procedure is also known as multi-unit gated acquisition (MUGA).

Why has my doctor ordered this test for me?
The reasons for this test vary. For example, you may have been diagnosed with heart failure or heart valve disease. You might have had a recent heart attack. This test provides important information which will help your doctor determine the best course of treatment for you.

What is a gated blood pool pharmacological test?
If your doctor has ordered an exercise MUGA, but you are unable to exercise, you will be given a drug which mimics the effect of exercise. Some people experience temporary side effects to this drug, which include: headache, nausea, or flushing (after a minute). These feelings only last 5 to 10 minutes.

Is this procedure dangerous?
Whenever the heart is stressed with exercise or a drug, there is a possible risk involved depending on the underlying problem. The risk of severe complications is extremely small. There is minimal radiation exposure which is comparable to several common chest x-rays.

What preparation is required?
If you suspect you are pregnant, discuss this with you referring physician prior to scheduling the test.

Resting gated blood pool imaging requires no preparation. Exercise gated blood pool imaging has the following requirements:

Don't eat after midnight of the day before the test. If you have diabetes, ask your physician what you may eat. If your appointment is late in the day, you may be allowed to have a light breakfast.

Wear comfortable clothing and shoes, suitable for exercise.

What happens during the test?
A technologist will first clean three areas on your chest, and then place three small self-sticking electrodes on those areas. He/she will attach them by leads to a nuclear imaging computer. Then the nuclear technologist will give you two injections.

You will lie down on a special bed. A nuclear camera will surround you, taking pictures of your heart. Some people feel a little claustrophobic. This part of the test may last for 20 minutes.

If you are having a test at rest, the technologist will take three pictures of your heart.

After the rest portion of the test, you may go on to the exercise portion of this test.

In the exercise portion, you will lie on your back and place your feet into pedals. Then while remaining in a supine position, you will pedal as if on a bicycle. Multiple images will be taken. A clinician is usually present for this part of the test.

How long does the test take?
Gated blood pool studies at rest require approximately one hour. Exercise studies usually take an hour and a half.

What happens after the test?
You will be free to resume your daily activities. It is usual to resume taking regular medications.

What happens next?
You will be able to drive yourself home. You will still have radioactivity inside you, but you cannot transmit this radiation to your loved ones. Your urine will be temporarily radioactive. The radioactivity will dissipate completely within two days.

Will my doctor notify me of the results?
Your doctor will receive a report and discuss the findings with you. Based on these findings, he/she will determine if additional testing is required.