Drug-eluting stents.

Drug-eluting stents represent the third revolution in the field of Interventional Cardiology following balloon angioplasty (PTCA) and the implantation of metal stents. The main limitation of percutaneous coronary intervention (PCI) is restenosis. The introduction of drug eluting stents able to release antiproliferative compounds led to the evaluation of several antiproliferative drugs in order to reduce restenosis. Rapamycin (Sirolimus) has been demonstrated to inhibit smooth muscle cell (SMC) proliferation and migration in vitro and to reduce in vivo neointima formation with blockage of the cell cycle progression at the G1-S transition. In a pilot study, recently confirmed by a randomized trial, rapamycin drug-eluting stents have been reported to eliminate restenosis after stent implantation. Promising data also come from the use of paclitaxel drug-eluting stents. Paclitaxel (Taxol) is a microtubule-stabilizing agent with potent antiproliferative activity. Even if drug-eluting stents represent one of the most promising fields in Interventional Cardiology today before being sure of their real potential it is necessary to wait for results from several ongoing clinical studies, their usage in real-world lesions and extended follow-up to 5 years.