Cardiac Blood Pool Scan
How It Feels
You may feel nothing at all from the
needle puncture when the tracer is injected, or you may feel a brief sting or
pinch as the needle goes through the skin. Otherwise, a cardiac blood pool scan
is usually painless. You will not feel anything from the operation of the gamma
camera. You may find it hard to remain still during the scan. The
examination table may feel cool. Ask for a pillow or blanket to make yourself
as comfortable as possible before the scan begins.
Allergic reactions to the radioactive
tracer are rare. Most of the tracer will be eliminated from your body (through
your urine or stool) within a day, so be sure to promptly flush the toilet and
thoroughly wash your hands with soap and water. The amount of radiation is so
small that it is not a risk for the people you come in contact with after the
Occasionally, some soreness or swelling may develop at the
injection site. These symptoms can usually be relieved by applying moist, warm
compresses to your arm.
There is always a slight risk of damage to
cells or tissue from being exposed to any radiation, including the low level of
radiation released by the radioactive tracer used for this test.
A cardiac blood pool scan shows how well
your heart is pumping blood to the rest of your body.
The most commonly reported
value is the
ejection fraction, which is the average amount of
blood pumped out of the heart's
left ventricle during each contraction.
Normal results include:1
- Ejection fraction is 55%
- Walls of the ventricles
are contracting normally.
Many conditions can affect cardiac
blood pool scan results. Your doctor will discuss any significant
abnormal results with you in relation to your symptoms and past health.
What Affects the Test
Reasons you may not be able to
have the test or why the results may not be helpful include:
- Fast or irregular heart
- Long-acting nitrate medicines and
- Recent nuclear scans, such as thyroid or bone
- Barium, such as from a
barium enema, and bismuth, such as
- Inability to remain still during the test. You may
not be able to have the test if you have severe back problems or other physical
disabilities that prevent you from lying flat.
What To Think About
- Cardiac blood pool
imaging is not usually done during pregnancy because the radiation could damage
- The cardiac blood pool scan is a safe and
accurate way to determine overall heart function.
acquisition (MUGA) scans are routinely used before and after receiving a heart
transplant to assess how well the heart is working. MUGA also may be used to
monitor the ejection fraction in people receiving chemotherapy.
- Generally, an
echocardiogram provides as much information as a MUGA
scan and is less invasive. But a MUGA scan provides more accurate
information about ejection fraction than an echocardiogram, especially in
people who are obese or who have lung disease. For more information, see the