Intravascular ultrasound is a test that uses sound waves to see inside blood vessels. It is useful for evaluating the coronary arteries that supply the heart.
IVUS; Ultrasound - coronary artery; Endovascular ultrasound; Intravascular echocardiography
A tiny ultrasound wand is attached to the top of a thin tube called a catheter. This ultrasound catheter is inserted into an artery in your groin area and moved up to the heart. It is different from conventional Duplex ultrasound, which is done from the outside of your body by placing the transducer on the skin.
A computer measures how the sound waves reflect off blood vessels, and changes the sound waves into pictures. IVUS gives the health care provider a look at your coronary arteries from the inside-out.
IVUS is almost always done at the end of angioplasty with stent placement, or coronary catheterization. Angioplasty gives a general look at the coronary arteries, but it cannot show the walls of the arteries. IVUS images show the artery walls and can reveal cholesterol and fat deposits (plaques). Buildup of these deposits can increase your risk of a heart attack.
IVUS has helped doctors understand how stents become clogged (stent restenosis).
Why the Procedure Is Performed
IVUS is commonly done to make sure a stent is correctly placed during angioplasty. It may also be done to determine where a stent should be placed.
IVUS may also be used to:
- View the aorta and structure of the artery walls (which can show plaque buildup)
- Find which blood vessel is involved in aortic dissection
There is a slight risk of complications with angioplasty and cardiac catheterization. However, the tests are very safe when done by an experienced team. IVUS adds little additional risk.
In general, risks may include:
- Allergic reaction to any dye used during the test, to the stent material, or to the drug used in a drug-eluting stent
- Bleeding or clotting in the area where the catheter was inserted
- Blood clot
- Clogging of the inside of the stent (in-stent restenosis)
- Complete blockage of blood flow in a certain area
- Damage to a heart valve or blood vessel
- Heart attack
- Irregular heartbeat (arrhythmia)
- Kidney failure (a higher risk in people who already have kidney problems or diabetes)
- Stroke (this is rare)
After the Procedure
After the test, the catheter is completely removed. A bandage is placed on the area. You will be asked to lie flat on your back with pressure on your groin area for a few hours after the test to prevent bleeding.
If IVUS was done during cardiac catheterization, you will stay in the hospital for about 3 to 6 hours. If IVUS was done during angioplasty, you will stay in the hospital for 12 to 24 hours. The IVUS does not add to the time you must stay in the hospital.
Tardif JC, L'Alliwer PL. Intravascular Ultrasound Imaging. In: Bonow RO, Mann DL, Zipes DP, Libby P, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 9th ed. Philadelphia, PA: Elsevier Saunders; 2011:chap 22.