What is angiography?
Angiography is an x-ray examination of the blood vessels after they have been filled with a contrast agent (a type of fluid that makes the vessels visible on an x-ray image). Angiography is performed when your physician suspects blockages of arteries that may interfere with the normal flow of blood through the body. It also is used to detect aneurysms, to image malformations in a blood vessel, to detect stroke or bleeding in the brain, and to find irregularities that can affect the vital organs.
Prior to your angiography examination, a number of blood tests will be performed, and you will be asked about the medications you take, whether prescription or over-the-counter. You will be asked if you have any allergies. It is important to list all allergies to food and medicine, as well as hay fever or asthma. Existing allergies may indicate a possible reaction to the contrast agent that will be used during the examination. If you are a women of childbearing age, you will be asked if there is any possibility that you are pregnant, because a fetus is sensitive to radiation. You will receive detailed instructions about how to prepare for your procedure. Follow these instructions carefully, including nothing to eat or drink for 8 hours prior to the procedure.
When you arrive for your angiogram you will be prepared for the procedure. You will be asked to remove all clothing and jewelry and to put on a hospital gown. The nurse will need to start an intravenous (IV) line for fluids and medications. When it is time for your procedure the Special Procedures Lab staff will explain the procedure to you and answer any questions you might have. Staff members present for the procedure are a radiology technologist, scrub technician or scrub nurse, and a nurse to monitor and care for your needs. The Radiologist will perform the procedure.
Some suggestions to help you prepare:
- Pack a small bag of overnight clothing and for the next day
- Do not bring any valuables.
- Bring a list of your medications (with exact names and dosages)
- Arrange for someone to drive you home.
- Empty your bladder for your own comfort.
- You may want to wear socks, dentures, hearing aids or glasses.
During the Examination
The staff will position you on the exam table and connect you to a blood pressure cuff, heart monitor and oxygen monitor. The Radiologist (a physician who specializes in the diagnostic interpretation of medical images) will administer a local anesthetic and them make a small nick in your skin so that a thin catheter can be inserted into an artery or vein. The catheter is a flexible, hollow tube about the size of a strand of spaghetti. It usually is inserted into an artery in your groin, although in some cases your arm or another site will be selected for the catheter.
The Radiologist will ease the catheter into the artery or vein and gently guide it to the area under investigation. The Radiologist will be able to watch the movement of the catheter on a fluoroscope, which is an x-ray unit combined with a television monitor. When the catheter reaches the area under study, the contrast agents will be injected through the catheter. By watching the fluoroscope screen, the Radiologist will be able to see the outline of your blood vessels and identify any blockages or irregularities.
Angiography procedures can range in time from less than an hour to three hours or more. It is important that you relax and remain as still as possible during the examination. The staff and physician stay in the room with you throughout the procedure. If you experience any difficulty, let them know.
Therapeutic uses of Angiography
In addition to imaging the blood vessels, angiography can be used to help repair them. During a procedure known as balloon angioplasty, angiography is used to guide a balloon through the catheter to a blocked or narrowed area of an artery. The balloon is inflated, compressing plaque against the walls of the artery and widening it. Then the balloon is deflated and the catheter is removed. In cases where the artery cannot be stretched by balloon angioplasty, a surgical stent can be inserted into the vessel to help keep it open. A stent is an expandable wire mesh tube, sized to fit your artery. Once in place, a stent can provide a better channel for blood flow through the artery.
Post Examination Information
After the procedure is complete, you will be moved to a room where you can rest and recover. Depending upon your overall health and medical condition, you may be released after just a few hours or you may be admitted to the hospital for observation and recovery. Before you go home, you will be given instructions explaining how to care for the site where the catheter was inserted. Your physician also may recommend that you restrict your activities at home. Follow the physician's instructions carefully.
Your kidneys will excrete any contrast agent that remains in your system. You will be advised to drink lots of water to help flush the contrast from your system. The amount of contrast is very small, and it has no odor or color. You will not notice any discoloration of you urine. In addition, the radiation that you are exposed to during this examination, like the radiation produced during any other x-ray procedure, passes through you immediately.
The Radiologist will review your angiogram and your personal physician will receive a report of the findings. Your physician then will inform you of the results and discuss what further procedures, if any are needed.