What is atherosclerosis?
Atherosclerosis (sometimes called “hardening” or “clogging” of the arteries) is the buildup of cholesterol and fatty deposits (called plaque) on the inner walls of the arteries that restrict blood flow to the heart. Atherosclerosis can affect the arteries in the heart, legs, brain, kidneys and other organs.
Atherosclerotic heart disease (coronary artery disease) is the narrowing or blockage of the coronary (heart) arteries. Your coronary arteries are shaped like hollow tubes through which blood can flow freely. Normally, the walls of the coronary arteries are smooth and elastic. Atherosclerosis occurs when the normal lining of the arteries deteriorates, the walls of the arteries thicken and deposits of fat and plaque build-up on the coronary artery walls, blocking or limiting the flow of oxygen-rich blood to the heart muscle.
Without adequate blood, the heart becomes starved of oxygen and the vital nutrients it needs to work properly. This can cause chest pain called angina. When one or more of the coronary arteries are completely blocked, a heart attack (injury to the heart muscle) may occur.
Experience is important
Catheterization and interventional procedures require special expertise. Physician credentials and experience lead to better outcomes. Coronary angiography was developed at Cleveland Clinic in 1958 by F. Mason Sones, MD. The F. Mason Sones Cardiac Catheterization Laboratory features eight catheterization laboratories. Please review our outcomes
The staff at Cleveland Clinic, the #1 heart hospital in the nation as ranked by U.S.News and World Report, has prepared a free detailed overview on Coronary Artery Disease and its treatment options, including medical, interventional and surgical options.
What is a cardiac catheterization?
Coronary artery disease is the narrowing or blockage of the coronary (heart) arteries, as shown in the illustration below. After an interventional procedure, the coronary artery is opened, increasing blood flow to the heart.
Cardiac catheterization (also called cardiac cath or coronary angiogram) is an invasive imaging procedure that allows your doctor to evaluate your heart function. Cardiac catheterization is used to:
- Evaluate or confirm the presence of coronary artery disease, valve disease or disease of the aorta
- Evaluate heart muscle function
- Determine the need for further treatment (such as an interventional procedure or coronary artery bypass graft, or CABG, surgery)
During a cardiac catheterization, a long, narrow tube called a catheter is inserted through a plastic introducer sheath (a short, hollow tube that is inserted into a blood vessel in your arm or leg). The catheter is guided through the blood vessel to the coronary arteries with the aid of a special x-ray machine. Learn more about cardiac catheterization.
Contrast material is injected through the catheter and x-ray movies are created as the contrast material moves through the heart’s chambers, valves and major vessels. This part of the procedure is called a coronary angiogram (or coronary angiography). The digital photographs of the contrast material are used to identify the site of the narrowing or blockage in the coronary artery.Additional imaging procedures, called intra-vascular ultrasound (IVUS) and fractional flow reserve (FFR), may be performed along with cardiac catheterization in some cases to obtain detailed images of the walls of the blood vessels. Both of these imaging procedures are currently only available in specialized hospitals and research centers.
With IVUS, a miniature sound-probe (transducer) is positioned on the tip of a coronary catheter. The catheter is threaded through the coronary arteries and, using high-frequency sound waves, produces detailed images of the inside walls of the arteries. IVUS produces an accurate picture of the location and extent of plaque.
With FFR, a special wire is threaded through the artery and a vasodilator medication is given. This test is functionally performing a very high quality stress test for a short segment of the artery. What is an interventional procedure?
What is an interventional procedure?
An interventional procedure is a non-surgical treatment used to open narrowed coronary arteries to improve blood flow to the heart. An interventional procedure can be performed during a diagnostic cardiac catheterization when a blockage is identified, or it may be scheduled after a catheterization has confirmed the presence of coronary artery disease.
An interventional procedure starts out the same way as a cardiac catheterization. Once the catheter is in place, one of these interventional procedures is performed to open the artery: balloon angioplasty, stent placement, rotablation or cutting balloon.
Balloon angioplasty: A procedure in which a small balloon at the tip of the catheter is inserted near the blocked or narrowed area of the coronary artery. The technical name for balloon angioplasty is percutaneous transluminal coronary angioplasty (PTCA) or percutaneous coronary intervention (PCI). When the balloon is inflated, the fatty plaque or blockage is compressed against the artery walls and the diameter of the blood vessel is widened (dilated) to increase blood flow to the heart. This procedure is sometimes complicated by vessel recoil and restenosis.
Balloon angioplasty with stenting: In most cases, balloon angioplasty is performed in combination with the stenting procedure. A stent is a small, metal mesh tube that acts as a scaffold to provide support inside the coronary artery. A balloon catheter, placed over a guide wire, is used to insert the stent into the narrowed artery. Once in place, the balloon is inflated and the stent expands to the size of the artery and holds it open. The balloon is deflated and removed, and the stent stays in place permanently. During a period of several weeks, the artery heals around the stent. In this way, restenosis is somewhat diminished.
Angioplasty with stenting is most commonly recommended for patients who have a blockage in one or two coronary arteries. If there are blockages in more than two coronary arteries, coronary artery bypass graft surgery may be recommended.
Drug-eluting stents (DES): Drug-eluting stents contain a medication that is actively released at the stent implantation site. Drug-eluting stents have a thin surface of medication to reduce the risk of restenosis.
Concern was raised in 2006 regarding the safety of drug-eluting stents due to the risk of blood clots forming on the stent, causing a heart attack. The Food and Drug Administration (FDA) continues to feel that DES, when used according to approved indications, are safe and effective.
Source: Update to FDA Statement on Coronary Drug-Eluting Stents (January 4, 2007).
If you receive a drug-eluting stent, your doctor will prescribe certain medications for several months after your procedure to prevent the risk of clotting in the stent. It is extremely important to keep taking the medications as prescribed until your doctor tells you otherwise.
If you have concerns about drug-eluting stents, please talk with your physician.
Rotablation (Percutaneous Transluminal Rotational Atherectomy or PTRA): A special catheter, with an acorn-shaped, diamond-coated tip, is guided to the point of narrowing in the coronary artery. The tip spins around at a high speed and grinds away the plaque on the arterial walls. This process is repeated as needed to treat the blockage and improve blood flow. The microscopic particles are washed safely away in your blood stream and filtered out by your liver and spleen.
Cutting balloon: The cutting balloon catheter has a balloon tip with small blades. When the balloon is inflated, the blades are activated. The small blades score the plaque, then, the balloon compresses the fatty matter into the arterial wall. This type of balloon may be used to treat the build up of plaque within a previously placed stent (restenosis) or other types of blockages.