Test Overview
An angiogram of the lung is an
X-ray test that uses a special dye and camera (fluoroscopy) to take pictures of the blood flow in the
blood vessels of the lung.
During an angiogram, a thin tube called
a catheter is placed into a
femoral blood vessel in the groin (femoral vein) or just above the elbow
(brachial 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. The angiogram pictures can be made
into regular X-ray films or stored as digital pictures in a computer.
A lung (pulmonary) angiogram is used to check the arteries that lead to
the lungs (pulmonary arteries) and the blood vessels in the lungs. It can also
find narrowing or a blockage in a blood vessel that slows or stops blood flow.
Why It Is Done
A lung angiogram may be done to measure the
pressure in the blood vessels carrying blood to the lungs, to look for lung
problems, or to find other causes of blockage or narrowing of the
vessels.
How To Prepare
Before 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 Done
An 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 test
You 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 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. Sometimes only one lung is studied, or the process may be
repeated more than once for each lung.
An angiogram takes 1 to 2 hours.
After the test
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. Then the area may be covered with a bandage or a compression device. 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.
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 Feels
You 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 feel a need to cough but try
to keep holding your breath until you are told to breathe.
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 stomach 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.
Risks
The 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.
- 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 from 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.
Results
An angiogram of the lung is an
X-ray test that uses a special dye and camera (fluoroscopy) to take pictures of the blood flow in the
blood vessels of the lung. Your doctor may tell you some results right after
the test. Full results are usually ready the same day.
Angiogram of the lungNormal: | The dye flows evenly through
the blood vessels. |
|---|
No narrowing, blockage,
bulging, or other problem of the blood vessels is seen. The pulmonary artery
pressures are normal. |
Abnormal: | Blood vessels that are not in
their normal position may mean that a tumor or other growth is pushing
against them. |
|---|
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 there is a hole in the blood
vessel. |
There is an abnormal vessel or
blockage between vessels in the lung. |
There is abnormal branching of
blood vessels present since birth (congenital). |
What Affects the Test
Reasons 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).
- Having a blocked blood vessel or another blood vessel
problem.
- Having high blood pressure in the blood vessels that carry blood
to the lungs (pulmonary hypertension).
- Not being able to lie still during the test.
- Having
an abnormal heart rhythm. Your doctor will talk to you about this.
What To Think About
- A computed tomography angiogram (CTA) or a
magnetic resonance angiogram (MRA) 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 doctors may want results
from a standard angiogram before doing surgery to treat 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.
References
Other Works Consulted
- 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.
Credits
ByHealthwise 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