- What is angiography?
- How do I prepare?
- What does the investigation involve?
- What happens after?
- Are there any risks?
What is angiography?
Angiography is an imaging investigation using x-rays to take pictures of your blood vessels. Physicians use digital subtractive angiography (DSA) to study narrow, blocked, enlarged or abnormal arteries or veins in many parts of the body, including the brain, the heart, the chest, the abdomen and the limbs. When arteries are studied, the investigation is more precisely called arteriography, whereas when veins are studied it is called venography.
Arteriography is performed as follows: to create the x-ray images, your physicians will inject a liquid, the “contrast”, through a thin, flexible tube, called a catheter. They pass the catheter into the desired artery or vein from an access point. The access point is usually in your groin but it can also be in your arm or wrist. The contrast, makes the blood flowing inside the blood vessels visible on an x-ray. The contrast is later eliminated from your body through your kidneys and your urine.
Sometimes the physicians may treat a problem during an arteriography. For example, they can perform balloon angioplasty and/or stenting to open up a narrow of occluded artey or embolize a tumour or vascular malformation.
How do I prepare?
Prior to arteriography, certain laboratory tests, such as checking blood clotting and kidney function, need to be performed. You usually come into the hospital on the day of the procedure or the day before.
The physician will have probably asked you to discontinue for a few days (if you take) any anticoagulant like Warfarin or Sintrom, but you generally you will not discontinue antiplatelet drugs like Clopidogrel (Iscover, Plavix) or Aspirin. You will be asked to be starved for 6 hours before the investigation and intravenous fluids may be administered to you as of the previous day to prevent deterioration of your kidney function.
If you are allergic to the contrast material or iodine, you may be preventively given some medication to reduce the risk of an allergic reaction.
What does the investigation involve?
Your test will be performed in a room equipped with a specialized x-ray machine. Your physicians will insert an IV to provide you with fluids and medications. They will choose where to insert the angiographic catheter, usually into an artery in your groin or near your elbow. Before the insertion, they will clean your skin with an antiseptic solution and shave any hair in the area to reduce your risk of infection. Your physician then numbs your skin with a local anaesthetic and makes a tiny puncture to reach the artery below. Your artery is punctured with a hollow needle, a thin wire is advanced through the needle, and then a catheter is passed over the wire guided it to the desired location. Your physician uses x-rays that are projected on a video screen, a process called fluoroscopy, to see the catheter as it moves through your arteries. Usually, your physician moves the x-ray table to follow the catheter as it is advanced through your blood vessel. Once your physician has positioned the catheter properly, the contrast is injected. The contrast causes a brief, mild warm feeling as it enters your bloodstream. Your physician takes more x-ray images to see how the contrast is flowing through your arteries. During the test, your physician may ask you to hold your breath for about 5 to 15 seconds. In addition, your physician may ask you to lie perfectly still to prevent sudden movements from blurring the x-ray pictures.
When the investigation is over, your physician will remove the catheter and will aplly pressure on the insertion site for 10-20 minutes with the fingers and then with a compression tape to prevent any bleeding. The whole investigation will take 30-60 minutes unless balloon angioplasty/stenting or embolization is performed.
What happens after?
If the artery in the elbow has been punctured, after a brief period of observation, you will be allowed to go home with certain instructions.
If the artery in the groin has been punctured, after arteriography you will be transferred back to your room for observation. Your physician will ask you to remain in bed with the leg used for the puncture in a straight position for several hours (to prevent bleeding) and will advise you when you can get up. You will be able to drink fluids and have a light meal later. Your physician will also tell you when you can start your medications again. If punctured in the groin, most people stay in the hospital overnight.
After discharge keep drinking plenty of fluids for 1-2 days and avoid strenuous activities, such as climbing stairs, driving or brisk walking for 12 hours. You may return to your normal activities as soon as you feel ready.
Are there any risks?
Risks are involved in any medical intervention. The overall risk from arteriography is very small.
– Bruising at the puncture site is common and usually resolves on its own within 1-2 weeks
– Bleeding, pain or swelling where the catheter was inserted
– Pain, numbness or coolness in your arm or leg. These symptoms may signify either bleeding from the puncture site or blockage of your artery and an operation may be required
– Rarely, impaired kidney function, or kidney failure, can occur following an angiogram, especially if you already have kidney disease
– Also rarely, allergic reactions can occur, especially among people who have had previous allergic reactions to the contrast. Severe reactions occur with a frequency of 1 in 3000
– Infrequently, if you suffer from asthma/ chronic bronchitis, angina pectoris or a heart condition associated with poor pumping action, such as congestive heart failure, you may experience shortness of breath or fluid overload. This may very rarely be a significant problem
Last modified 11/11/2015
