The present and future of drug-eluting stents.

The only widely accepted way to reduce restenosis rate after percutaneous balloon angioplasty has been the use of coronary bare metal stents, and the last decade has witnessed a prompt and widespread adoption of bare metal stents that has revolutionized the field of interventional cardiology. The new millennium has seen the recent development of drug-eluting stents (DES), allowing controlled release of a drug directly to the injured artery, which seem to have prevented by large the problem of in-stent restenosis. The goal of this review was to summarize recent laboratory and clinical investigations concerning the effects of DES in various settings relevant to coronary heart disease. In the experimental setting, we examine the intracellular signaling and the role of smooth muscle cells after vascular injury. We also discuss recent observations from our laboratory showing the effects of coating per se on cell apoptosis and proliferation. In the clinical setting, the effects of DES in patients with stable or unstable angina pectoris is examined in detail for the relevant implications both in the treatment and prognosis. The results of a meta-analysis on the effects that have been overlooked in individual studies are reported which show a striking reduction in bypass surgery after DES implantation. Finally, we discuss the potential role of new materials and technologies (i.e., nanotechnology) that will improve DES performance allowing other future clinical applications in patients with ST-elevation myocardial infarction, vulnerable plaques, insulin-dependent diabetes mellitus, etc.