Angiography in the broadest meaning is looking at blood vessels, both arteries and veins. This lesson examines angiography performed in a hospital procedure lab and explains common complications.
What is an Angiography?
Have you ever known someone who had to go in for a test after having chest pain, horrible cramping leg pain coupled with a lack of pulses in the feet, or mini-stroke type symptoms? Or perhaps someone you know was having trouble breathing and was suspected to have a lung clot? Any of these scenarios could be the reason for having angiography done.
Angiography is the test where dyes that can be seen by x-rays are injected into blood vessels (either arteries or veins) and examined using x-rays. The resulting pictures are called angiograms. Angiograms are used to diagnose narrowing or blockages in vessels anywhere in the body, from head to toe, including:
- The arteries feeding the heart muscle
- The arteries going to the brain
- The arteries feeding the arms and legs
- The arteries feeding the kidneys
- All of the vessels going to and coming from the lungs
In addition to finding narrowing and blockages, angiography can also be used to find places where the arteries or veins are bulging or ballooning. These spots are called aneurysms and if not treated, can cause death when they rupture.
In order to do an angiogram, the patient is taken into a special procedure room. Oftentimes these rooms will have a setup similar to this one:
In the picture, you can see the bed where the patient will be placed and the c-arm that produces the x-rays that then are digitally transmitted to the set of screens on the other side of the patient bed. At some point prior to procedure, the patient’s groin or area above the elbow is clipped or shaved and then cleaned with a surgical prep solution. Sterile drapes are then placed to help ensure that bacteria are not introduced directly into the patient’s blood stream.
Oftentimes, the patient is given fluids and some medication through an IV to help him or her relax during the procedure. Monitors for blood pressure, the heart’s electrical activity, and blood oxygen levels are also placed so that medical personnel in the room can keep an eye on the patient’s condition. A thin tube called a sheath is then placed in a major blood vessel (aka the access site) to allow the doctor to place different catheters into the vessels of interest and inject dye. As the dye is injected, the patient may get a warm flushed feeling in the body part being examined.
In this picture (below), you can see the catheter has been threaded up through the femoral artery which goes to the lower part of the aorta, which is the major artery coming out of the heart. The physician can then inject dye and see the outline of the aorta under x-ray to check for narrowing or aneurysms.
In this image (below), dye has been injected into the arteries feeding the heart muscle. The arrows indicate significant blockages that will need to be fixed using angioplasty or a coronary artery bypass graft.
The more common complications from angiography are related to the dye used and the access site itself. The medical personnel will watch for signs of bleeding around the site until you go home. Swelling, bleeding, or a collection of blood under the skin (called a hematoma) may occur at this site if the major vessel is not adequately sealed over. Minor bruising at the access site is not uncommon and will go away with time. Patients will be given precautions to follow for one to two weeks after the procedure to avoid the access site opening back up.
If a patient has any kind of history of kidney disease, additional precautions must be taken. Extra fluids and medications may be given to help clear the dye out of the body without causing damage to the kidneys.
If the patient has a history of heart failure or kidney damage, caution may need to be used in terms of how much fluid is given since fluid overload could occur, leading to problems with breathing.
Allergic reactions to the dye may occur. If the patient is allergic to shellfish or iodine, he or she is often pre-medicated with steroids and antihistamines to help avoid reactions to the dye used during the procedure.
Other less common, but more serious, complications that may occur include:
- Damage to the blood vessels being examined
- Heart attack or stroke during angiography looking at the heart vessels, due to a piece of plaque being knocked off down into the vessel
- A blood clot downstream of the area being examined
Let’s review. Angiography is a fairly common procedure used to directly examine the blood vessels for blockages or narrowing. The procedure is done in a sterile manner to avoid introducing bacteria directly into the patient’s blood stream. A dye that can be seen under x-ray is injected into the vessels, and the resulting pictures (called angiograms) are examined in real time by the physician performing the procedure. Potential complications include bleeding at the access site, hematoma formation, allergic reaction to dye, and potential kidney damage in patients with compromised kidney function.