Renal angiography; Renal artery stenosis – arteriography
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.
Renal arteriography is a special x-ray of the blood vessels of the kidneys.
How the Test is Performed
This test is done in the hospital. You will lie on an x-ray table.
Health care providers often use an artery near the groin for the test. Occasionally provider may use an artery in the wrist. Your provider will:
- Clean and shave the area.
- Apply a numbing medicine to the area.
- Place a needle into the artery.
- Pass a thin wire through the needle into the artery.
- Take out the needle.
- Insert a long, narrow, flexible tube called a catheter in its place.
The radiologist directs the catheter into the correct position using x-ray images of the body. An instrument called a fluoroscope sends the images to a TV monitor, which the provider can see.
The catheter is pushed ahead over the wire into the aorta (main blood vessel from the heart). It then enters the kidney artery. The test uses a special dye (called contrast) to help the arteries show up on the x-ray. The blood vessels of the kidneys are not seen with ordinary x-rays. The dye flows through the catheter into the kidney artery.
X-ray images are taken as the dye moves through the blood vessels. Saline (sterile salt water) containing a blood thinner may also be sent through the catheter to keep blood in the area from clotting.
The catheter is removed after the x-rays are taken. A closure device is placed in the groin or pressure is applied to the area to stop the bleeding. The area is checked after 10 or 15 minutes and a bandage is applied. You may be asked to keep your leg straight for 4 to 6 hours after the procedure.
How to Prepare for the Test
Tell the provider if:
- You are pregnant
- You have ever had any bleeding problems
- You currently take blood thinners, including daily aspirin
- Have you ever had any allergic reactions, especially those related to x-ray contrast material or iodine substances
- You have ever been diagnosed with kidney failure or poorly functioning kidneys
You must sign a consent form. DO NOT eat or drink anything for 6 to 8 hours before the test. You will be given a hospital gown to wear and asked to remove all jewelry. You may be given a pain pill (sedative) before the procedure.
How the Test will Feel
You will lie flat on the x-ray table. There is usually a cushion but it is not as comfortable as a bed. You may feel a sting when the anesthesia medicine is given. You will not feel the dye. You may feel some pressure and discomfort as the catheter is positioned.
Some people feel a warm sensation when the dye is injected; however, most people cannot feel it. There may be slight tenderness and bruising at the site of the injection after the test.
Why the Test is Performed
Renal arteriography is often needed to help decide on the best treatment after other tests are done first. These include duplex ultrasound, CT abdomen, or a CT angiogram. These tests may show the following problems.
- Abnormal widening of an artery, called an aneurysm
- Abnormal connections between veins and arteries ( fistulas )
- Blood clot blocking an artery supplying the kidney
- Unexplained high blood pressure is thought to be due to the narrowing of the blood vessels of the kidneys
- Benign tumors and cancers involving the kidneys
- Active bleeding from the kidney
This test is often used to examine donors and recipients before a kidney transplant. The result determines the number of arteries and veins on each kidney.
Normal Results
Results may vary. Talk to your doctor about the meaning of your specific test results.
What Abnormal Results Mean
Renal angiography may show the presence of tumors, narrowing of the artery or aneurysms (widening of the vein or artery), blood clots, fistulas, or bleeding in the kidney.
The test may also be done with the following conditions:
- Blockage of an artery by a blood clot
- Renal artery stenosis
- Renal cell cancer
- Angiomyolipomas (noncancerous tumors of the kidney)
Some of these problems can be treated with techniques done at the same time the arteriogram is performed.
- Angioplasty is a procedure to open narrowed or blocked blood vessels that supply blood to your kidneys.
- A stent is a small, metal mesh tube that keeps the artery open. It may be placed to keep a narrowed artery open
Risks
The procedure is generally safe. There may be some risks, such as:
- Allergic reaction to the dye (contrast medium)
- Arterial occlusion from dissection
- Damage to the artery or artery wall, which can lead to blood clots
- Kidney damage from damage to the artery or from the dye
There is low radiation exposure. Pregnant women and children are more sensitive to the risks related to x-rays.
Considerations
The test should NOT be done if you are pregnant or have severe bleeding problems.
Magnetic resonance angiography (MRA) or CT angiography (CTA) can be done instead. MRA and CTA are noninvasive and can provide similar imaging of the kidney arteries, although they cannot be used for treatment.
