Magnetic Resonance Angiography (MRA)
What is magnetic resonance angiography (MRA)?
You’ve probably heard about the test called MRI. An MRI uses radio waves, a magnetic
field, and a computer create a scan of your body to look for health problems.
Magnetic resonance angiography (MRA) is a type of MRI. It looks just at the body’s
blood vessels. A regular angiogram requires inserting a thin tube (catheter) into
your body. MRA is a less invasive and less painful test.
During MRA, you lie flat inside an MRI scanner. This is a large, tunnel-like tube.
In some cases, contrast dye may be added to your bloodstream. This is done to make
your blood vessels easier to see. The contrast is put into your vein with an IV (intravenous)
Why might I need MRA?
If your healthcare provider thinks that you may have a narrowing or blockage of blood
vessels somewhere in your body, he or she may advise MRA. Other conditions that your
healthcare provider can look for during this test include:
An aneurysm or weakness in the wall of an artery
A narrowing of the aorta (aortic coarctation)
Bleeding in and along the wall of the aorta (aortic dissection)
To find the cause of a stroke
Signs of heart disease
Narrowing or blockage of the vessels in the arms or legs
Renal (kidney) artery stenosis, a narrowing of the blood vessels in the kidneys that
can lead to high blood pressure and even kidney failure
What are the risks of MRA?
If a dye is needed to make the blood vessels easier to see during the test, you may
have a bit of discomfort because of the insertion of the IV.
You might also have some anxiety when placed inside the MRI scanner. This is a small,
narrow space. If you think you might be claustrophobic, be sure to tell your healthcare
provider before the scan. You may be given a mild sedative to make it easier to be
in the MRI scanner.
Some risks of MRA include:
You may have be injured if you have metal objects in pockets or clothing or metal
implants (such as a pacemaker or bullet fragment) in your body. Before you have the
test, you will be asked a series of detailed questions about any metal you may have
in your body.
If you have a problem with your kidneys, you are at risk of a severe reaction from
the MRA contrast dye. This reaction can affect your skin, joints, liver, and lungs.
If you have a history of kidney disease, your healthcare provider may decide that
an MRA is not safe for you.
Pregnant women may have additional risks in the MRI scanner. Make sure to tell your
healthcare provider if you are or might be pregnant.
You may be at risk for other complications. This depends on your specific medical
condition. Be sure to discuss any concerns with your healthcare provider before the
Tell your healthcare provider or the technician doing your test if you:
Have ever had an imaging test (MRA, MRI, or CT) with contrast dye
Are allergic to contrast dye, iodine, shellfish, or any medicines
Have a serious health problem such as diabetes or kidney disease
Are pregnant, may be pregnant, or are breastfeeding
Have any implanted device or metal clips or pins in your body
How do I get ready for MRA?
Before your test:
Remove your watch and any jewelry, coins, and other metal objects from your clothes
and body. Don't forget to remove earrings, ankle bracelets, and other jewelry. This
includes pierced jewelry.
Tell your healthcare provider if you have any metal screws, surgical staples, bullet
fragments, or other metal in your body. This includes a heart pacemaker, intrauterine
device (IUD), implanted neurostimulator, or insulin or chemotherapy port.
You may want to ask for a blanket or a pillow to be more comfortable on the MRI scanner
Ear plugs can be helpful. The machine can be loud as it does the scan.
What happens during MRA?
MRA may be done on an outpatient basis or during a hospital stay. Generally, it follows
You will remove any clothing, jewelry, or other objects that may interfere with the
scan and put on a gown.
If you need a contrast dye to make blood vessels easier to see, this will be given
through an IV.
You will be positioned on an exam table directly outside the MRI scanner.
The table will slide into position, placing you inside the MRI scanner.
You will need to lie still during the scanning process. Any movements can blur the
images and cause the results to be less accurate.
The MRI scanner typically makes a lot of noise, including loud humming noises, so
don’t be alarmed.
The full scan may take an hour or longer. This will depend on the type and number
of blood vessels that your healthcare provider wishes to examine.
The scan typically causes no side effects or complications. If it is done on an outpatient
basis, you are generally free to leave after the scan. Your healthcare provider will
likely schedule a follow-up appointment to review the results of the test.
What happens after MRA?
Your healthcare provider will examine the images from the MRA. If no blockages or
problems are found, you have what’s called a normal test result. An abnormal result
means that the healthcare provider noted a problem in one or more of the blood vessels
in your body. This may mean that you have hardening of the arteries (atherosclerosis)
or another blood vessel problem. Your healthcare provider will likely advise other
tests or treatments based on the results of the MRA.
Before you agree to the test or the procedure make sure you know:
The name of the test or procedure
The reason you are having the test or procedure
What results to expect and what they mean
The risks and benefits of the test or procedure
What the possible side effects or complications are
When and where you are to have the test or procedure
Who will do the test or procedure and what that person’s qualifications are
What would happen if you did not have the test or procedure
Any alternative tests or procedures to think about
When and how will you get the results
Who to call after the test or procedure if you have questions or problems
How much will you have to pay for the test or procedure