Angiogram

Why It Is Done

An 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 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 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 test

An 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 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 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.

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).
• 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.
  • Magnetic Resonance Angiogram (MRA)
  • CT Scan of the Body
• 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.
  • Creatinine and Creatinine Clearance
  • Blood Urea Nitrogen
• 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.