James J Nawarskas1, Larry A Osborn. 1. College of Pharmacy, University of New Mexico, Albuquerque, NM 87131-0001, USA. jnawarskas@salud.umn.edu
Abstract
PURPOSE: Clinical information regarding paclitaxel-eluting coronary artery stents is reviewed. SUMMARY: Restenosis is a significant complication of percutaneous coronary intervention. Coronary artery stenting has reduced restenosis compared with traditional balloon angioplasty, although restenosis still occurs with bare-metal coronary artery stents. The pathogenesis of in-stent restenosis is believed to involve smooth-muscle-cell proliferation and migration in response to vessel injury. A neointimal layer of extracellular matrix and collagen forms, which may impinge on the vessel lumen. Paclitaxel inhibits vascular smooth-muscle-cell proliferation and reduces neointimal mass. Local delivery of paclitaxel through a coronary stent has been shown to reduce restenosis rates and percent diameter stenosis and to produce other angiographic benefits compared with bare-metal stents. Fewer major adverse coronary events are seen with paclitaxel-eluting stents, predominantly because of a reduction in the need for target-vessel revascularization with minimal impact on rates of mortality and myocardial infarction (MI). The Taxus Express(2) stent, the only approved paclitaxel-eluting stent in the United States, costs about three times as much as a bare-metal stent. Cost-effectiveness analyses are needed to determine if the Taxus stent is cost-effective in clinical practice. CONCLUSION: Paclitaxel-eluting stents reduce the rates of restenosis and target-vessel revascularization compared with bare-metal stents and have comparable effects on mortality and MI rates.
PURPOSE: Clinical information regarding paclitaxel-eluting coronary artery stents is reviewed. SUMMARY:Restenosis is a significant complication of percutaneous coronary intervention. Coronary artery stenting has reduced restenosis compared with traditional balloon angioplasty, although restenosis still occurs with bare-metal coronary artery stents. The pathogenesis of in-stent restenosis is believed to involve smooth-muscle-cell proliferation and migration in response to vessel injury. A neointimal layer of extracellular matrix and collagen forms, which may impinge on the vessel lumen. Paclitaxel inhibits vascular smooth-muscle-cell proliferation and reduces neointimal mass. Local delivery of paclitaxel through a coronary stent has been shown to reduce restenosis rates and percent diameter stenosis and to produce other angiographic benefits compared with bare-metal stents. Fewer major adverse coronary events are seen with paclitaxel-eluting stents, predominantly because of a reduction in the need for target-vessel revascularization with minimal impact on rates of mortality and myocardial infarction (MI). The Taxus Express(2) stent, the only approved paclitaxel-eluting stent in the United States, costs about three times as much as a bare-metal stent. Cost-effectiveness analyses are needed to determine if the Taxus stent is cost-effective in clinical practice. CONCLUSION:Paclitaxel-eluting stents reduce the rates of restenosis and target-vessel revascularization compared with bare-metal stents and have comparable effects on mortality and MI rates.