Angiogram
Test OverviewAn angiogram is an
X-ray test that uses a special dye and camera (fluoroscopy) to take pictures of the blood flow in an
artery (such as the
aorta) or a vein (such as the vena cava). An angiogram
can be used to look at the arteries or veins in the head, arms, legs, chest,
back, or belly. Common angiograms can look at the arteries near
the heart (coronary angiogram), lungs (pulmonary angiogram), brain (cerebral
angiogram), head and neck (carotid angiogram), legs or arms (peripheral), and
the aorta (aortogram). During an angiogram, a thin tube called a
catheter is placed into a blood vessel in the groin (femoral artery or vein) or
just above the elbow (brachial artery or vein). The catheter is guided to the area to be
studied. Then an iodine dye (contrast material) is injected into the
vessel to make the area show clearly on the X-ray pictures. This method is
known as conventional or catheter angiogram. The angiogram pictures can be made
into regular X-ray films or stored as digital pictures in a computer. An angiogram can find a bulge in a blood vessel (aneurysm). It
can also show narrowing or a blockage in a blood vessel that affects blood
flow. An angiogram can show if
coronary artery disease is present and how bad it
is. A
magnetic resonance angiogram (MRA) or
computed tomography angiogram (CTA) may be an option
instead of an angiogram. Each of these tests is less invasive than a standard
angiogram. Some MRA tests and all CTA tests require an injection of dye. A CTA
also involves radiation exposure. - Heart Disease: Should I Have an Angiogram?
Why It Is DoneAn
angiogram is done to: - Detect problems with blood vessels that affect
blood flow. Examples of such problems include a tear in a blood vessel (which
can cause blockage or internal bleeding),
aneurysms (which are weaknesses in the blood vessel
wall), and narrowed areas.
- Look for changes in the blood vessels of
injured or damaged organs.
- Show the pattern of blood flow to a
tumor. This can not only help show how much the tumor has spread but also guide
treatment.
- Show the condition, number, and
location of renal arteries before a kidney transplant.
- Look for a source of bleeding, such as an
ulcer.
- Prepare for surgery on diseased
blood vessels of the legs (peripheral arterial disease) in people
who have severe leg pain when walking.
- Check how bad
atherosclerosis is in the
coronary arteries.
In some cases, a method called interventional radiology may
be used during an angiogram to treat diseases. For example, a catheter can be
used to open a blocked blood vessel, deliver medicine to a tumor, or stop
intestinal bleeding caused by
diverticular hemorrhage. To stop intestinal bleeding,
the catheter is moved into the small artery where the bleeding is occurring,
and medicine that narrows the artery or causes the blood to clot is injected
through the catheter. How To PrepareBefore an angiogram, tell your doctor
if you: - Are or might be pregnant.
- Are
breastfeeding. Use formula (throw out your breast milk) for 1 to 2 days after
the angiogram until the dye has passed from your body. This generally takes 24
hours.
- Are allergic to iodine dye used in the
test.
- Have ever had a serious allergic reaction (anaphylaxis) from any substance, such as the venom
from a bee sting or from eating shellfish.
- Have
asthma.
- Are allergic to any
medicines.
- Have any bleeding problems or are taking blood-thinning
medicines.
- Have a history of kidney problems or
diabetes, especially if you take metformin (such as
Glucophage) to control your diabetes. The dye used during an angiogram can
cause kidney damage in people who have poor kidney function.
Do not eat or drink for 4 to 8 hours before the angiogram.
You may be asked to not take aspirin, aspirin products, or blood thinners for
several days before the test and for 1 day after the test. If you take these
medicines, talk with your doctor. An angiogram can be done as an
inpatient or outpatient. If you are an outpatient, you will stay in a recovery
room for several hours before you go home. You may want to bring something to
do or read to pass the time. Arrange to have someone take you home because you
may get a
sedative before the test. If you stay overnight in the
hospital, you will probably go home the next day. The test may
take several hours, so you will empty your bladder just before it
begins. Also before the angiogram you may have other blood tests,
such as blood clotting (coagulation) studies, blood urea nitrogen (BUN), and
creatinine. You will be asked to sign a consent form that says you understand the risks of the test and agree to have it done. Talk to
your doctor about any concerns you have regarding the need for the test, its
risks, how it will be done, or what the results will mean. To help you
understand the importance of this test, fill out the
medical test information form(What is a PDF document?). How It Is DoneAn angiogram can be done by different types of doctors, including a
radiologist, cardiologist, or surgeon. Your doctor may be helped by a radiology technologist or a nurse. You will need to
take off any jewelry. You may need to take off all or most of your clothes. You
will be given a gown to wear during the test. During the testYou will likely have
an
intravenous (IV) line in a vein in your arm so your
doctor can give you medicine or fluids if needed. A device called a pulse
oximeter, which measures oxygen levels in your blood, may be clipped to your
finger or ear. Small pads or patches (electrodes) are placed on your arms, chest, or legs
to record your heart rate and rhythm. You will lie on your back on
an X-ray table. Ask for a pad or blanket to make yourself comfortable. A strap,
tape, or sandbags may be used to hold your body still. A lead apron may be
placed under your genital and pelvic areas to protect them from X-ray
exposure. A round cylinder or rectangular box that takes the
pictures during fluoroscopy will be moved above you. The fluoroscope will move
under you during the test. The place where the catheter will be
inserted (in the groin or above the elbow) will be shaved and cleaned. Your
doctor will numb the area with a
local anesthetic. Then he or she will put a needle
into the blood vessel. A guide wire will be put through the needle into the
blood vessel and the needle will be removed. The catheter will be placed over
the guide wire and moved into the blood vessel. The catheter then will be
guided through the blood vessels until the tip is in the area to be studied.
Your doctor will use the fluoroscope to watch the movement of the catheter in
the blood vessels. When the catheter is in place, the dye is
injected through it. You may be asked to take a breath and hold it for several
seconds. Several X-ray pictures will be taken one after another. These will be
available right away for your doctor to look at. You need to lie very still so
the pictures are clear. More pictures may be taken. After the testAn angiogram takes 1 to 3 hours. The
catheter is taken out after the angiogram, and pressure is put on the needle
site for 10 to 15 minutes to stop any bleeding. A bandage or compression device is put on the site. This will prevent bleeding. You will be
given pain medicine if you need it. If the catheter was put in your groin, you will need to lie still and keep your leg straight for several hours. The nurse may put a weighted bag on your leg to keep it still. If the catheter was put in your arm, you may be able to sit up and get out of bed right away. But you will need to keep your arm still for at least 1 hour. Your doctor will give you specific
instructions after the test. You can use an ice pack on the needle site to
relieve pain and swelling. The place in your hands and feet where
your heartbeat (peripheral pulse) can be felt may be marked with a pen. Your
pulse may be checked before and after the angiogram. How It FeelsYou may feel a brief sting or pinch from
the numbing medicine. Most people do not have pain when the catheter is in the
blood vessel. You may feel pressure in the blood vessel as the
catheter is moved. Let your doctor know if you are having pain. You will probably feel some warmth when the dye is put in. This feeling
lasts only a few seconds. For some people, the feeling of heat is strong and
for others it is very mild. You may have a headache, flushing of
the face, or a salty or metallic taste in your mouth after the dye is used.
These feelings do not last long. Some people may feel sick to their stomachs or
may vomit, but this is not common. After the test, you may have
some tenderness and bruising at the site where the catheter was
inserted. You can drink extra fluids to pass the dye from your
body unless your doctor has told you not to. RisksThe chance of any major problem from an
angiogram is very small, but some problems can occur. In most cases, the
problems occur within 2 hours after the test when you are in the recovery room.
If the problem occurs during the angiogram, the test may not be completed. You
may need urgent treatment that could include surgery. - There is a chance of an
allergic reaction to the iodine dye. The reaction can
be mild (itching, rash) or severe (trouble breathing or sudden shock). Most
reactions can be treated with medicines. Be sure to tell your doctor if you
have
hay fever,
asthma, or iodine allergy or food allergies.
- There is a small chance that the catheter may damage a blood
vessel or dislodge a piece of clotted blood or fat from the vessel wall. The
clot or fat can block blood flow to the brain, arm, leg, or intestine
(bowel).
- Bleeding from the needle site may occur. Also, a blood
clot can form where the catheter was inserted. This may cause some blockage of
the blood flow in the arm or leg.
- The iodine dye used for the test can cause water loss or direct
damage to the kidneys. This is a special concern for people who have kidney
problems,
diabetes, or who are
dehydrated. Special measures are used during the test
to prevent problems for people who need an angiogram and have these
conditions.
- There is always a small chance of damage to cells or
tissue from being exposed to any radiation, even the low level used for this
test.
ResultsAn angiogram is an
X-ray test that uses a special dye and camera (fluoroscopy) to take pictures of the blood flow in an
artery (such as the
aorta) or a vein (such as the vena cava). Your doctor
may tell you some results right after the test. Full results are usually ready the same day. AngiogramNormal: | The
blood vessels are normal in shape, size, location, and number. |
|---|
The
dye flows evenly through the blood vessels. | No
narrowing, blockage, bulging, or other problem of the blood vessels is
seen. | Abnormal: | Blood
vessels that are not in their normal position may mean that a tumor or
other growth is pushing against them. |
|---|
A
narrow spot in an artery may mean that a fat deposit, calcium deposit, or
clot is reducing blood flow through the blood vessel. | A
bulge in a blood vessel may mean a weakness in the blood vessel wall (aneurysm). | Dye that leaks out of a blood vessel may mean a
hole in the blood vessel. | There
is abnormal branching of blood vessels present since birth
(congenital). | An
abnormal pattern of blood vessels may mean that a tumor is
present. | What Affects the TestReasons you may not be able to
have the test or why the results may not be helpful include: - Being pregnant. An angiogram is not usually
done during pregnancy because the radiation could damage the developing baby
(fetus).
- Blockage or curving of the blood
vessels caused by
atherosclerosis,
high blood pressure, or aging. This may make it hard
to guide the catheter through the blood vessels or hard to inject the
dye.
- Not being able to lie still during the test.
What To Think About- A magnetic resonance angiogram (MRA) or
computed tomography angiogram (CTA) may be an option instead of an angiogram.
Each of these tests is less invasive than a standard angiogram. Some MRA tests
and all CTA tests require an injection of dye. A CTA also involves radiation
exposure. Some surgeons may want results
from a standard angiogram before doing surgery to repair a damaged or abnormal
blood vessel.
- For people with kidney problems,
diabetes, or
dehydration, steps are taken to prevent kidney damage.
Less dye may be used or more fluids may be given before, during, and after the
test. If you have a history of kidney problems, other blood tests (creatinine,
blood urea nitrogen) may be done before an angiogram to make sure that your
kidneys are working well.
- In rare cases,
surgery may be needed to repair a hole in the blood vessel where the catheter
was placed. There is also a substance that can be used to
help plug the hole in the vessel and stop the bleeding. The substance used to
plug the hole in the vessel is normally absorbed by the body over several
months.
ReferencesOther Works Consulted- Bluemke, D, et al. (2008). Noninvasive coronary artery imaging: Magnetic resonance angiography and multidetector computed tomography angiography. A scientific statement From the American Heart Association Committee on Cardiovascular Imaging and Intervention of the Council on Cardiovascular Radiology and Intervention, and the Councils on Clinical Cardiology and Cardiovascular Disease in the Young. Circulation, 118: 586-606.
- Chernecky CC, Berger BJ (2008). Laboratory Tests and Diagnostic Procedures, 5th ed. St. Louis: Saunders.
- Pagana KD, Pagana TJ (2010). Mosby's Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby.
CreditsByHealthwise Staff
Primary Medical ReviewerRakesh K. Pai, MD, FACC - Cardiology, Electrophysiology
Adam Husney, MD - Family Medicine
Martin J. Gabica, MD - Family Medicine
E. Gregory Thompson, MD - Internal Medicine
Specialist Medical ReviewerHoward Schaff, MD - Diagnostic Radiology Current as ofMarch 16, 2017 Current as of:
March 16, 2017 Last modified on: 8 September 2017
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