Arteriography

Angiography is a type of xray that is done to image blood vessels in various parts of the body, including the heart, brain and kidneys, so as to determine whether the vessels are diseased, narrowed, enlarged or blocked altogether. After passing a catheter through an artery leading to the body area of interest, contrast material is injected to highlight the vessels when x-rays are taken. Today, many catheter angiographic studies have been replaced by less invasive methods, such as computed tomography (CT) angiography and magnetic resonance (MR) angiography that do not require a catheter be inserted. Catheter angiography still is widely used in patients who may undergo surgery, angioplasty or stent placement.

Common reasons to do catheter angiography are to detect narrowing or blockage of a blood vessel, identify abnormally dilated blood vessels, and to determine the site of internal bleeding. The procedure is able to:

• Show atherosclerotic disease in the arteries of the neck, which may limit blood flow to the brain and even cause a stroke.
•  Demonstrate an intracranial aneurysm or other disorders of the blood vessels in the brain.
• Indicate disease in the renal artery causing hypertension or help prepare for a kidney transplant.
• Determine the state of the aorta and detect an aneurysm of this vessel.
• Demonstrate a source of bleeding, such as a stomach ulcer.
• Help prepare for surgery on diseased blood vessels in the legs of patients who have severe leg pain when walking.
• Surgeons sometimes use angiography to plan an operation or to decide on the best surgical procedure. Using catheter angiography as an aid to see inside blood vessels, interventional radiologists can repair diseased vessels from within using tiny instruments to keep the vessel open.

What to expect with your procedure

You should not eat anything eight hours ahead of time (usually after midnight). You may have clear fluids until shortly before the examination. You may receive an intravenous (IV) sedative in preparation for angiography and should anticipate not driving for 24 hours afterward. An observation period is necessary before you can leave. If you will be going home the same day, you should arrange alternative transportation.

Preparing for your procedure

After removing jewelry and donning a hospital gown, you should empty your bladder. A small amount of blood will be drawn before starting the procedure to make sure that your kidneys are working and that your blood will clot normally, and an IV line will be set up. Before the procedure you will have to give your consent. This usually involves a face-to-face talk with a physician, nurse or technologist. You should bring a list of your medicines. If you are a diabetic taking insulin, you should contact the radiology department nursing staff before the day of the procedure. If you have any allergies, you should tell the physician before the exam begins. Also, the radiology staff should know if there is a possibility that you may be pregnant.

A small dose of sedative is usually given through the IV line, not to make the patient sleep but to lessen their anxiety during the procedure. Local anesthesia is injected into the skin at the site of puncture, which is most often at the top of the leg at the site of the femoral artery. A small incision is made after cleaning and shaving the skin at this site in order to introduce the catheter into the artery. The radiologist threads the catheter through the arterial system to the desired location and then injects the contrast material. Usually several sets of x-rays are taken and, after the procedure is completed, the catheter is removed and the puncture site closed by compressing it for about 10 minutes (or by using a special closure device). You will have to lie flat for two to six hours after angiography, depending on the reason for the exam, the catheter size, and the type of device used to close up the artery. During this time, you should inform the nurse if you notice any bleeding, swelling or pain at the site where the catheter entered the skin. The entire procedure may take less than an hour or as long as several hours.