Traditionally, patients with blocked coronary arteries undergo angioplasty, a procedure in which a balloon-tipped catheter is guided into the artery.
Once there, the balloon expands and holds the artery open. Over the past several years, angioplasty has been combined with—or in some cases replaced by—the insertion of stents, small wire-mesh tubes that act as a kind of “scaffolding” to hold the arterial walls open. However, even with stents, about a quarter of patients experience restenosis—or reblockage—of the arteries within several months.
The latest development in this area is drug-eluting stents. Drug-eluting stents are coated with medications derived from certain cancer drugs. When inserted into a coronary artery, the stent elutes or “delivers” the medication over a period of months. This continuous bathing in medication prevents arterial tissue cells from overgrowing and causing restenosis.
Just how effective are these new fangled stents? In one European study, participants were divided into five different groups—four groups that received stents coated with varying doses of medication and a control group. After six months, the patients who had received the highest drug doses showed a restenosis rate of just 3.1 percent, while more than one-fifth of the control group experienced restenosis. In another study, there was no incidence of restenosis seven months after participants received drug-coated stents compared with 26 percent of those who received conventional stents—and just 3.3 percent experienced a major cardiac event such as a heart attack or death during the follow-up period compared with 27 percent in the control group.
According to researchers, there’s still more to learn about drug-eluting stents and their effects on different segments of the population. For now, though, they remain a promising treatment and should continue to have a significant impact on cardiac care.
Although patients who get drug-eluting stents are much less likely to experience restenosis than patients who have bare metal stents, another blockage is always a possibility. If the stent is appropriately placed, restenosis is much less likely. What doesn’t seem to do much: drugs and vitamins administered either orally or intravenously.
If restenosis occurs, treatment may include a second angioplasty, bypass surgery (in which blood vessels are rerouted around clogged arteries, much like traffic is rerouted around a jammed-up road) or radiation inside the artery, known as brachytherapy. Although only a small percentage of restenosis is currently treated this way, this type of therapy appears to be gaining momentum.
Restenosis often causes symptoms such as chest pain and pressure triggered by exertion, but you can experience restenosis without even being aware of it. Diabetics in particular seem to have fewer symptoms. Your best course of action? Have your doctor check you at regular intervals to be sure your stents are doing their job.