Angioplasty Stent by Bruce Holliday
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- Original Title:
What Happens During Angioplasty?
First, a cardiac catheterization is performed during angioplasty. You will receive medication for relaxation, and then the doctor will numb the site with local anesthesia. Next, a sheath (a thin plastic tube) is inserted into an artery -- usually in your groin, but sometimes in the arm. A long, narrow, hollow tube, called a catheter, is passed through the sheath and guided up the blood vessel to the arteries surrounding the heart. A small amount of contrast material is injected through the catheter and is photographed as it moves through the heart's chambers, valves, and major vessels. From the digital pictures of the contrast material, the doctors can tell whether the coronary arteries are narrowed and/or whether the heart valves are working correctly.
Once the catheter engages the artery with the blockage, the doctor will perform one of the interventional procedures described below.
The procedure usually lasts about 1 1/2 to 2 1/2 hours, but the preparation and recovery time add several hours. You may stay in the hospital overnight to be observed by the medical staff.
What Types of Interventional Procedures Are Used in Angioplasty?
There are several types of interventional procedures which your doctor may use when performing angioplasty. They include: Balloon angioplasty. During this procedure, a specially designed catheter with a small balloon tip is guided to the point of narrowing in the artery. Once in place, the balloon is inflated to compress the fatty matter into the artery wall and stretch the artery open to increase blood flow to the heart.
Stent. A stent is a small metal mesh tube that acts as a scaffold to provide support inside your coronary artery. A balloon catheter, placed over a guide wire, is used to insert the stent into the narrowed coronary artery. Once in place, the balloon tip is inflated and the stent expands to the size of the artery and holds it open. The balloon is then deflated and removed while the stent stays in place permanently. Over a several-week period, your artery heals around the stent. Stents are commonly placed during interventional procedures such as angioplasty to help keep the coronary artery open. Some stents contain medicine and are designed to reduce the risk of reblockage (restenosis). The doctor will determine if this type of stent is appropriate for your type of blockage.
Rotoblation. A special catheter, with an acorn-shaped, diamond-coated tip, is guided to the point of narrowing in your coronary artery. The tip spins around at a high speed and grinds away the plaque on your artery walls. The microscopic particles are washed safely away in your blood stream and filtered out by your liver and spleen. This process is repeated as needed to allow for better blood flow. This procedure is rarely used today because balloon angioplasty and stenting have much better results and are technically easier for the cardiologist to perform.
Atherectomy. The catheter used in this procedure has a hollow cylinder on the tip with an open window on one side and a balloon on the other. When the catheter is inserted into the narrowed artery, the balloon is inflated, pushing the window against the fatty matter. A blade (cutter) within the cylinder rotates and shaves off any fat that protruded into the window. The shavings are caught in a chamber within the catheter and removed. This process is repeated as needed to allow for better blood flow. Like rotoblation, this procedure is rarely used today.
Cutting Balloon. The cutting balloon catheter has a special 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 artery wall.