Technology has introduced a wide variety of stents to be used after a balloon angioplasty to help increase blood flow and reduce the amount of subsequent clotting and scarring. A stent is a small metal mesh tube that provides support within the coronary artery. The balloon catheter is used to insert the stent into the narrowed section of the artery. When the balloon is inflated, the stent molds to its size and stays permanently. Two different stents have been developed which have more benefits than their simple metal counterparts.
In Atlanta, Georgia, in 2002 at the American College of Cardiology meeting, the concept of a drug-coated stent was introduced. The stent was to be coated with the drug rapamycin, normally used to prevent inflation during kidney transplants. Drug-coated stents have since proven to be far more effective at reducing restenosis than plain metal stents. However, these stents are much more expensive. The OSIRIS trial in Europe tested the effects of orally administering this drug. The results indicated that taking rapamycin orally was also effective—and significantly cheaper—but less effective than using the drug-coated stent.
Another option which has only recently been made available is a degradable stent. At the West German Heart Center in Essen, Dr. Raimund Erbel said in an interview with HealthDay that the center had developed a stent that biodegrades and disappears from the artery in a few months. The stent is made of magnesium, which the body can easily handle and scientists can monitor through MRI or CT scans. In the case of permanent metal stents, most patients require Plavix or aspirin, clot-dissolving drugs, but patients with magnesium stents require no such drugs. However, reblocking did occur in almost half of the patients, indicating there is still a lot of work that needs to be done to make the procedure more effective.
Some scientists criticize the use of degradable metal stents, believing a biomaterial must be found that is less likely to cause problems in the latter stages of degradation. These procedures are still very young and still need a lot of work before they can be deemed suitable for mass use.
