What is an Angiogram?
An angiogram is a test that allows physicians to see how blood flows through a specific blood vessel (an artery or a vein). The procedure uses a dye that makes blood vessels visible on X-rays. An angiogram can be used to look at the blood vessels in the head, chest, back, abdomen, arms or legs. An angiogram can reveal the presence of any blockage or damage in an artery or vein, an aneurysm, as well as coronary artery disease and its extent.
Some angiograms have specific names.
- Cerebral angiogram: used to look at a blood vessel in the brain
- Carotid angiogram: used to look at a blood vessel in the neck
- Coronary angiogram: used to look at blood vessels around the heart
- Pulmonary angiogram; used to look at a blood vessel in the lungs
- Peripheral angiogram: used to look at a blood vessel in an arm or leg
During an angiogram, a catheter (a thin, flexible tube) is placed into a blood vessel and guided to the area to be examined. Then a dye is injected into blood stream. This dye causes the blood vessel to be visible on an X-ray. Therefore, the X-rays must be taken while the dye is flowing through the blood vessel being studied.
Why is an Angiogram Performed?Angiograms may be done to:
- Detect/locate an aneurysm
- Detect things that adversely affect blood flow in a vessel (e.g., a tear, or areas of blockage)
- Look for the cause of internal bleeding
- Prepare for peripheral arterial disease surgery
- Observe the blood vessels of organs that have been damaged or injured
- Determine which blood vessels are supplying nutrients to a tumor
- Determine the exact location, number and condition of blood vessel prior to certain organ transplants
- Assess the extent of atherosclerosis
- Provide access to a blood vessel for treatment (e.g., insertion of a catheter to open a blocked vessel, stop internal bleeding, or deliver medicine directly into a tumor)
How is an Angiogram Performed?
An angiogram can be done as an outpatient procedure; however, after the procedure, patients stay in a recovery room for several hours before they can go home. A radiologist and another doctor, in addition to other support staff, perform the test.
An angiogram may last anywhere from 30 minutes to several hours. Patients are awake during the test and are often given a mild sedative to help them relax. Most patients will have an intravenous line in a vein in their arm to administer any medication or fluids that are needed. Small pads will be placed in several areas to help monitor the patient’s heart rate.
The test requires several steps:
- The catheter will be inserted either into the groin, neck or just above the elbow. This area first must be shaved, cleaned then numbed with a local anesthetic.
- A needle is then inserted into a blood vessel; a small wire will be passed through the needle and the needle removed.
- A thin hollow tube (catheter) is placed over the wire and moved into the blood vessel.
- The catheter is then guided through the blood vessel until it reaches the area to be studied.
- X-rays are taken to help see the exact location of the tip of the catheter.
- Once the catheter is in place, a dye is injected through it. The dye flows through the blood vessel and makes it visible on an X-ray.
- As soon as the dye is injected a series of X-ray will be taken. These reveal how the dye moves through the vessel. These X-ray are called angiograms.
- The catheter is removed when the test is completed, and pressure is applied to the needle site for 10 to 15 minutes to stop any bleeding.
- The insertion site will be bandage and an ice pack may be applied to relieve any pain and/or swelling.
Patients do not experience pain when the catheter is in the blood vessel. They may, however, feel pressure as the catheter is inserted and moved around. Patients generally feel some warmth for a few seconds when the dye is injected.
What can the Results of an Angiogram Reveal?
The results of an angiogram are typically available the same day as the procedure. Since an angiogram is a test to see how blood flows through a specific blood vessel, it can reveal the presence of any blockage or damage in an artery or vein, an aneurysm, and coronary artery disease and its extent.
Normal angiogram: the dye flows evenly through the blood vessel(s) examined. This means that those specific blood vessels are normal; there is no blockage, narrowing, bulging or other problems.
Abnormal angiogram: here the dye does not flow evenly through the blood vessel(s); a bulge or narrowing is seen in the vessel; the dye leaks from the vessel; or the vessel is in an abnormal location and/or there is an abnormal pattern of vessels. Abnormal results may be due to a variety of things including: a clot, a deposit of fat or minerals, an aneurysm, a hole in the vessel, or the presence of a tumor.