Stentstiny stainless steel coils used to shore up collapsed or clogged arteries may be the cause of restenosis, or continued narrowing of the arteries.
While restenosis rates have always been high after stent implantation, scientists have been at a loss to explain why. The common trend is to blame the patients and/or their lifestyles, but new evidence suggests that the very components of the stent may be responsible.
Stainless steel stents contain a mixture of metals, including nickel and molybdenum, and allergic reactions to these metals may be an important cause of instent restenosis.
In a study of 131 men who had stents implanted, 89 (68 per cent) experienced restenosis. Ten patients (8 per cent) were allergic to one or more of the metals in the stent. All of the patients with allergic reactions to stent materials experienced recurrent angina and required further surgery (Lancet, 2000; 356: 1895-7).