What is a renal angiogram?
A renal angiogram is an imaging test to look at the blood vessels in your kidneys.
Your healthcare provider can use it to look at the ballooning of a blood vessel (aneurysm),
narrowing of a blood vessel (stenosis), or blockages in a blood vessel. He or she
can also see how well blood is flowing to your kidneys.
For the test, the radiologist injects a contrast dye into the artery that brings blood
into the kidney. Then he or she uses X-ray images to watch the dye as it flows through
the blood vessels in the kidneys.
X-rays use a small amount of radiation to create images of your bones and internal
organs. A renal angiogram is one type of X-ray.
Fluoroscopy is used during a renal angiogram. Fluoroscopy is a kind of X-ray movie.
Why might I need a renal angiogram?
You may need a renal angiogram to help your healthcare provider find problems in the
blood vessels of your kidneys. These problems may include:
- Bulging of a blood vessel (aneurysm)
- Narrowing of a blood vessel (stenosis)
- Spasm of a blood vessel (vasospasm)
- An abnormal connection between arteries and veins (arteriovenous malformation)
- Blood clot (thrombosis)
- Blockage (occlusion)
You may also need a renal angiogram to help your provider diagnose:
- Bleeding (hemorrhage)
- Complications from a kidney transplant
You may need a renal angiogram if another test such as a CT scan or MRI did not give
your provider enough information.
Your healthcare provider may have other reasons to recommend a renal angiogram.
What are the risks of a renal angiogram?
You may want to ask your healthcare provider about the amount of radiation used during
the test. Also ask about the risks as they apply to you.
Consider writing down all X-rays you get, including past scans and X-rays for other
health reasons. Show this list to your provider. The risks of radiation exposure may
be tied to the number of X-rays you have and the X-ray treatments you have over time.
Tell your healthcare provider if you:
- Are pregnant or think you may be pregnant. Radiation exposure during pregnancy may
lead to birth defects.
- Are allergic to or sensitive to any medicines, contrast dye, or iodine. Because contrast
dye is used, there is a risk for allergic reaction to the dye.
- Have kidney failure or other kidney problems. In some cases the contrast dye can cause
kidney failure. You are at higher risk for this if you take certain diabetes medicines.
Possible complications of a renal angiogram include:
- Injury to nerves
- Blood clot (embolus)
- Swelling caused by a collection of blood (hematoma)
- Temporary kidney failure
- Damage to an artery or an artery wall. This can cause blood clots.
You may have other risks depending on your specific health condition. Be sure to talk
with your provider about any concerns you have before the procedure.
Certain things can make a renal angiogram less accurate. These include:
- Having contrast dye still in your body from a recent imaging test
- Gas or stool in the intestines
How do I get ready for a renal angiogram?
- Your healthcare provider will explain the procedure to you. Ask him or her any questions
you have about the procedure.
- You may be asked to sign a consent form that gives permission to do the procedure.
Read the form carefully and ask questions if anything is not clear.
- You'll be asked to not eat or drink liquids (fast) before the procedure. Your healthcare
provider will tell you how long to fast. It might be several hours or overnight.
- Tell your provider if you are pregnant or think you may be.
- Tell your healthcare provider if you are allergic to contrast dye or iodine.
- Tell your healthcare provider if you are sensitive to or are allergic to any medicines,
latex, tape, or anesthetic drugs (local and general).
- Tell your provider about all medicines you are taking. This includes prescriptions,
over-the-counter medicines, and herbal supplements.
- Tell your healthcare provider if you have had a bleeding disorder. Also tell your
provider if you are taking blood-thinning medicine (anticoagulant), aspirin, or other
medicines or herbal supplements that affect blood clotting. You may need to stop these
medications before the test.
- You may get medicine to help you relax (sedative) before the test.
- Depending on the site used for injection of the contrast dye, the recovery period
may last up to 12 to 24 hours. You may need to spend the night.
- You may need a blood test before the procedure to see how long it takes your blood
to clot. You may also need other blood tests.
- Follow any other instructions your provider gives you to get ready.
What happens during a renal angiogram?
You may have a renal angiogram as an outpatient or as part of your stay in a hospital.
The way the test is done may vary depending on your condition and your healthcare
Generally, a renal angiogram follows this process:
- You will be asked to remove any clothing, jewelry, or other objects that might get
in the way of the test.
- You will be given a gown to wear.
- You will be asked to empty your bladder before the test.
- You will lie on the X-ray table.
- An intravenous (IV) line will be started in your arm or hand.
- You will be connected to an EKG monitor. It will record the electrical activity of
your heart during the test. Medical staff will watch your heart rate, blood pressure,
and breathing rate during the test.
- The radiologist will check your pulses below the injection site for the contrast dye.
He or she will use a marker to note them. This is so that staff can check the circulation
to the limb below the site after the test.
- The nurse or technician will shave the skin in an area of your groin. He or she will
clean the skin and inject local pain medicine. The radiologist will put a needle into
an artery in your groin. Sometimes an artery in the elbow area may be used instead.
If the elbow site is used, a blood pressure cuff will be put on your arm below the
IV site. It will be inflated to keep the contrast dye from going into your lower arm.
- The radiologist will put a long thin tube (catheter) into the artery. He or she will
move the catheter into the aorta near the renal arteries. The radiologist will use
fluoroscopy to see where the catheter is.
- The radiologist will inject the contrast dye. You may feel a flushing sensation, a
salty or metallic taste in the mouth, a brief headache, or nausea or vomiting. These
effects usually last for a few moments.
- Tell the radiologist if you have trouble breathing, or if you have sweating, numbness,
or heart palpitations.
- The radiologist will take several sets of X-rays pictures. The first set shows the
arteries. The second set shows the blood flow in the capillaries and veins.
- Depending on the study being done, you may need more injections of contrast dye.
- Once the test is done, the radiologist will remove the catheter. He or she will put
pressure on the site to keep the artery from bleeding.
- After the bleeding stops, he or she will put a dressing on the site. The radiologist
may put something heavy on the site for a period of time. This will help stop bleeding
and keep blood from collecting (hematoma) at the site.
What happens after a renal angiogram?
You will be taken to the recovery room. A nurse will watch your vital signs and the
injection site. He or she will check the circulation and sensation in the leg where
the catheter was used.
You will need to lie flat in bed for several hours after the test. The leg or arm
used for the injection site will be kept straight for up to 12 hours.
You may be given pain medicine to ease pain or discomfort from the injection site
or from having to lie flat and still.
You will be told to drink water and other fluids to help flush the contrast dye from
When you leave the recovery room, you may go to a hospital room or be sent home. If
you had the test done as an outpatient, you will need to have someone drive you home.
You may go back to your usual diet and activities after the test, unless your healthcare
provider tells you otherwise.
Once at home, you should watch the injection site for bleeding. A small bruise is
normal. So is an occasional drop of blood at the site.
You should watch the leg or arm for changes in temperature or color, pain, numbness,
tingling, or loss of movement.
Drink plenty of fluids to help the contrast dye leave your body. Fluids will also
keep you from getting dehydrated.
You may not be able to do any strenuous activities or take a hot bath or shower for
a period of time after the test.
Tell your healthcare provider if any of these occur:
- Fever or chills
- Increased pain, redness, swelling, or bleeding or other fluid draining from the groin
- Coolness, numbness, tingling, or other changes in the arm or leg
Your healthcare provider may give you other instructions, depending on your situation.
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