A drug eluting or medicated stent is a small tube or conduit coated with different types of medication, which is principally used in cardiac procedures to keep a blood vessel open. These devices were first successfully tested in the early 2000s and now there are a number of them available on the market. The purpose of coating the stent with drugs is that these will be released into the artery, preventing the formation of scar tissue, which, in turn prevents blockage of the stent. Since its introduction, the medicated stent has known controversy because it seems statistically more likely to encourage blood clotting and increase the risk for stroke. Due to these risks, special medical guidelines are followed when these stents are used.
One of the potential risks of a bare metal stent is that it may irritate the blood vessel and cause scar tissue formation. This leads to what is known as stent restenosis or narrowing, and it may result in the need to replace the stent or to take other medical measures to repair and keep the blood vessel open. The medicated stent was first celebrated as a solution to this problem because it tended to greatly lower restenosis risk by inhibiting scar tissue from forming. Special drugs used to accomplish this, which elute or release from the stent include sirolimus and paclitaxel. More medications are under study as potentially beneficial to coat stents, with particular interest in coatings that are biodegradable.
Numerous research studies have proven that medicated stent types are more effective than non-medicated kinds when it comes to preventing stent restenosis. By the middle of the first decade of the 2000s, there was also proof that drug eluting stents placed people at increased risk for blood clots. Even though over the course of stent use, patients with medicated stents seemed to be fare better, statistically significant risk of forming thrombi was higher in medicated stent group users. For a time, this news evoked panic among the stent-producing industry. More studies suggested a way to approach this problem and retain medicated stents as a viable choice for patients.
Given the known increased risk for blood clots if a medicated stent is used, it’s now standard to give therapy that will help keep the blood from clotting for half a year to 12 months or longer. Commonly, the drug Plavix® (clopidogrel) is used, and it may be used in conjunction with aspirin. Therapy is usually begun immediately after stent placement. Its principal disadvantage can be expense, especially since people who receive stents are likely to be over 65 and may have limited prescription drug coverage.
