An update on clinical and pharmacological aspects of drug-eluting stents

The introduction of stents to clinical practice was the major breakthrough in the field of percutaneous coronary intervention. The introduction of stents was associated with two serious complications, the first was increase in subacute thrombosis within the first 30 days of stent implantation later controlled with the use of high pressure inflation and dual antiplatelet therapy, the second was the phenomenon of in-stent restenosis that was primarily caused by smooth muscle proliferation. While coronary stenting eliminates elastic recoil, it is unable to inhibit excessive neointimal formation. Stents were associated with an increase of neointimal formation compared to balloon angioplasty as a result of excessive injury to the vessel wall and the inflammatory process from interaction of metal with vessel wall. Local delivery of the potential agents for inhibition of neointimal formation to the site of the lesion was considered the desired approach. Several compounds have been tested for stent coating, primarily with the aim of the inhibition of SMC proliferation. Recently, new stents have emerged which are loaded with anti-inflammatory, anti-migratory, anti-proliferative or pro-healing drugs. In this review article the results of clinical studies investigating drug-eluting stents are discussed from pharmacological and clinical points of view, reviewing the current literature and the future prospective.