The long-term effectiveness of stents in the body depends on several factors, but in many cases, they may remain in the body and continue to do their job for over several decades. Stents are small tubes, normally made of metal mesh or ceramic that are placed in an artery to either open it up to blood flow, or keep a weakened artery from collapsing or bursting. First used in the 1980s, some original stents are still producing the desired results.
Stents are not a cure for a blocked artery, even though they do permit blood flow, and they are often accompanied by another procedure. Angioplasty, a technique in which a balloon is inserted into the artery and expanded to permit blood flow, may be followed by adding one or more stents. These small tubes are inserted into the artery, once again permitting flow in the circulatory system. Stents may be used near the heart, in the carotid artery, or in arteries in the extremities and other parts of the body. The length of time that they remain useful depends on the type of stent used, post operative change in lifestyle, and medications.
Stents may become blocked eventually if certain precautions are not taken. Those who have blocked arteries are instructed to change to healthier eating habits, avoiding fats and cholesterol, and are usually put on a low dose aspirin regimen, if they are not bothered by allergic reactions to aspirin. For those who can tolerate it, aspirin, even in low doses helps to prevent blood platelets from sticking together, which ultimately may cause blocked arteries, heart attacks, and strokes.
Patients are also encouraged to develop a program of exercise, maintain a healthy weight, and are always advised to remain on prescribed medications. In many cases, the patient may already be on blood pressure or cholesterol medicine, which may slow down the accumulation of more plaque in the artery. Certain stents are coated with medications prior to insertion, that deliver medication through the artery continuously, helping to prevent blockage.
Statistically speaking, where coronary stents are used, there is a less than a 20% chance that the artery will close again in less than a year, and will need to either be replaced, or some other procedure implemented. In many cases, this may involve by-pass surgery. Using the stent initially, however still slows the blockage, and eliminates much of the risk of heart attack or stroke.
New technology involving stents is expected to continue to improve both the procedure and the long term benefits.
"What Is a Stent?" National Heart, Lung and Blood Institute. 17 Dec. 2010. Web. 17 Dec. 2010. http://www.nhlbi.nih.gov/health/dci/Diseases/stents/stents_whatis.html.
"Angioplasty and Vascular Stenting." RadiologyInfo - The Radiology Information Resource for Patients. 17 Dec. 2010. Web. 17 Dec. 2010. <http://www.radiologyinfo.org/en/info.cfm?pg=angioplasty>.