Comparative angioscopic evaluation of neointimal coverage and thrombus between TAXUS-Express and TAXUS-Liberté stents: Is the stent platform type associated with the vascular response?

Abstract

Current drug-eluting stent (DES) has demonstrated marked reductions in restenosis following stenting [ [1] Morice M.C. Serruys P.W. Sousa J.E. et al. A randomized comparison of a sirolimus-eluting stent with a standard stent for coronary revascularization. N Engl J Med. 2002; 346: 1773-1780 Crossref PubMed Scopus (3846) Google Scholar ]. However, very late stent thrombosis (VLST) has become a major clinical problem as a catastrophic complication of DES [ [2] McFadden E.P. Stabile E. Regar E. et al. Late thrombosis in drug-eluting coronary stents after discontinuation of antiplatelet therapy. Lancet. 2004; 364: 1519-1521 Abstract Full Text Full Text PDF PubMed Scopus (1325) Google Scholar ]. DES caused the substantial impairment in arterial healing characterized by the lack of complete re-endothelialization and the presence of uncovered stent struts without endothelialization is considered a principal mechanism of VLST after DES placement [ [3] Finn A.V. Joner M. Nakazawa G. et al. Pathological correlates of late drug-eluting stent thrombosis: strut coverage as a marker of endothelialization. Circulation. 2007; 115: 2435-2441 Crossref PubMed Scopus (1140) Google Scholar ]. DES consists of three elements: drug, polymer and stent platform. One factor affecting the vascular response was the non-uniform distribution of stent struts [ [4] Takebayashi H. Mintz G.S. Carlier S.G. et al. Nonuniform strut distribution correlates with more neointimal hyperplasia after sirolimus-eluting stent implantation. Circulation. 2004; 110: 3430-3434 Crossref PubMed Scopus (137) Google Scholar ]. The open-cell-design DES tends to cause the mal-distribution of the drug and might be unfavorable for the arterial healing process. Two types of paclitaxel-eluting stents (PES) are available: the open-cell-design TAXUS-Express (TAXUS-Express [ [2] McFadden E.P. Stabile E. Regar E. et al. Late thrombosis in drug-eluting coronary stents after discontinuation of antiplatelet therapy. Lancet. 2004; 364: 1519-1521 Abstract Full Text Full Text PDF PubMed Scopus (1325) Google Scholar ]; Boston Scientific Corp., Natick, MA, USA) and the recently available closed-cell-design TAXUS-Liberté (Taxus®-Liberté™; Boston Scientific Corp.) [ [5] Turco M.A. Ormiston J.A. Popma J.J. et al. Polymer-based, paclitaxel-eluting TAXUS Liberté stent in de novo lesions: the pivotal TAXUS ATLAS trials. J Am Coll Cardiol. 2007; 49: 1676-1683 Abstract Full Text Full Text PDF PubMed Scopus (106) Google Scholar ]. To compare the vascular response between the TAXUS-Express and TAXUS-Liberté stent platforms, their effect on the vessel wall could be examined. Coronary angioscopy is a useful technique to evaluate detailed information about the neointimal stent coverage and the thrombus [ 6 Takano M. Ohba T. Inami S. et al. Angioscopic differences in neointimal coverage and in persistence of thrombus between sirolimus-eluting stents and bare metal stents after a 6-months implantation. Eur Heart J. 2006; 27: 2189-2195 Crossref PubMed Scopus (77) Google Scholar , 7 Yamamoto M. Okamatsu K. Inami S. et al. Relationship between neointimal coverage of sirolimus-eluting stents and lesion characteristics: a study with serial coronary angioscopy. Am Heart J. 2009; 158: 99-104 Abstract Full Text Full Text PDF PubMed Scopus (19) Google Scholar , 8 Takano M. Yamamoto M. Murakami D. et al. Lack of association large angiographic late loss and low risk of in-stent thrombus: angioscopic comparison between paclitaxel- and sirolimus-eluting stent. Circ Cardiovasc Intervent. 2008; 1: 20-27 Crossref PubMed Scopus (26) Google Scholar ]. Therefore, we investigated the influence of the neointimal stent coverage and the prevalence of in-stent thrombus by angioscopy using the different TAXUS stent platforms.