ABSTRACT
A number of systemic antiproliferative approaches to reduce restenosis after angioplasty have been tested, but promising results from experimental laboratories have not been translated into clinical effectiveness.1 The failure to achieve adequate drug concentrations in the target coronary segment is the major drawback of systemic antirestenotic drug therapy. Local drug delivery systems have been proposed to overcome this problem. Clinical experience with microporous, hydrogel balloons, iontophoretic catheters, dispatch catheters and infusion sleeves has been reported.2-6 However, the rapid washout of the drug downstream into the coronary circulation decreases the amount of agent actually deposited within the arterial wall to <5%.2,7 As a result of their permanent scaffolding action, stents have become the most attractive reservoir for sustained delivery of intramural antiproliferative agents. A prolonged and sufficient local drug concentration may be achieved via drug-eluting stents a novel antirestenotic technology recently introduced into the clinical arena.
