What Is a Heart CT Scan?
tomography scan — commonly called a CT scan or CAT scan — is a test that uses
X-rays to view specific areas of your body. These scans use safe amounts of
radiation to create detailed images of the body, which can help your doctor to
detect any problems. A heart, or cardiac, CT scan is used to view your heart
and blood vessels.
test, a specialized dye will be injected into your bloodstream. The dye is then
viewed under a special camera in a hospital or testing facility.
A heart CT
scan may also be called a coronary CT angiogram if it’s meant to view the
arteries that bring blood to your heart. The test may be called a coronary
calcium scan if it’s meant to determine whether there is a buildup of calcium
in your heart.
Why a Heart CT Scan Is Performed
may order a heart CT scan to look for certain conditions, including:
defects in the heart (congenital heart disease)
of a hard substance known as lipid plaque that may be blocking your coronary
or injury to the heart’s four primary valves
clots within the heart’s chambers
in or on the heart
A heart CT
scan is a common test for people experiencing heart problems, since it allows
your doctor to explore the structure of the heart and the adjacent blood vessels
without making any incisions.
The Risks of a Heart CT Scan
A heart CT
scan carries very few risks. Most of the dyes used for CT scans contain iodine,
which is later flushed from the body by the kidneys. If your kidneys have been
impacted by disease or infection, such as diabetes, you may need to drink extra
fluids after the test to help your kidneys remove the dye. However, newer dyes
carry much less risk to the kidneys.
As with any
X-ray, there is some exposure to radiation. While typically harmless, this is
an important issue for women who are pregnant or could be pregnant. The levels
of radiation are considered safe for adults — there have been no documented
side effects from low levels of radiation — but not for a developing fetus.
How to Prepare for a Heart CT Scan
will typically ask you to fast for four to eight hours before the scan. You’ll
be able to drink water. However, avoid caffeinated drinks since caffeine can
affect your heart rate.
You will be
required to lie down on a table during the exam, so you may want to wear loose,
comfortable clothing. You will also need to remove any jewelry and other metal
items from your body, such as piercings.
test, you will be able drive yourself home. There is no need to arrange for
How a Heart CT Scan Is Performed
A heart CT
scan is performed in a hospital’s radiology department or a clinic that
specializes in diagnostic procedures.
You may be
given a beta-blocker before
the scan. This medication will slow down your heart so that clearer pictures
can be taken. You’ll also be given an IV so that the technician can inject the
radioactive dye into your arm. Small, sticky discs called electrodes will be
placed onto your chest to record the scan.
At the start
of the scan, you’ll lie down on a bench. The technician may want you to lie in
a specific position. He or she may use pillows or straps to ensure that you
stay in the correct position for long enough to get a quality image. You may
also have to hold your breath during brief individual scans, which last only 10
to 20 seconds.
To start the
scan, the technician will move the table — via a remote from a separate room — into
the CT machine. A CT machine looks like a giant doughnut made of plastic and
metal. You will most likely go through the machine several times. Although you
will be in the room by yourself, the technician will be able to talk to you via
After a round
of scans, you may be required to wait for a few minutes while the technicians
review the images to ensure they are clear enough for your doctor to read. The
whole test should take no longer than 10 minutes.
After a Heart CT Scan
procedure, you’ll be able to leave and go about your day. The dye will
naturally work its way out of your body. Drinking more water will help speed up
results from your heart CT scan doesn’t take long. Your doctor or the
technician will go over the results with you.
what the images show, your doctor will advise you of any lifestyle changes,
treatments, or procedures that need to be done.