Angiographic patterns of restenosis after paclitaxel-eluting stent implantation.

e d o the Editor: Polymer-based paclitaxel-eluting stents (PES) Taxus, Boston Scientific, Natick, Massachusetts) have been hown to reduce neointimal hyperplasia and risk of restenosis (1,2). perators are now using drug-eluting stents for a wide variety of linical and anatomical situations, many of which have not been nvestigated in randomized studies. The clinical and morphologic features of restenosis after PES mplantation have not been adequately evaluated (1,2). The purose of this study was to describe the angiographic patterns of estenosis after PES implantation in “real-world” patients. This nowledge may help in finding the solution to this important roblem. We identified 977 consecutive patients who underwent PES mplantation (977 procedures, 1,688 lesions, 2,023 stents) in three nstitutions between April 2002 and March 2004. Patients that ad in-stent restenosis (ISR) lesions treated, prior brachytherapy at he target vessel, or acute myocardial infarction 48 h before the ndex procedure were excluded. All patients were pretreated with iclopidine or clopidogrel and aspirin; a loading dose of 300 mg lopidogrel was given to patients not previously taking the agent. spirin was continued indefinitely and clopidogrel or ticlopidine or at least six months after PES implantation. Glycoprotein Ib/IIIa inhibitors were administered at the operators’ discretion. During follow-up, coronary angiograms were obtained as clincally driven ( 30 days after procedure, indicated by symptoms or ositive ischemic tests). In addition, follow-up angiograms were btained at 6 1 month in patients treated with PES implantaion for bifurcations, left main, chronic total occlusions, small essels, and long stented length ( 36 mm). Cineangiograms were nalyzed using a validated edge detection system (CMS, version .2, MEDIS, Leiden, the Netherlands). Standard qualitative and uantitative analyses and definitions were used (3). Angiographic uccess was defined as a minimum stenosis diameter 20% after tenting. For the current study, ISR cases were categorized ccording to Mehran classification (4). Baseline demographics, lesion, and procedural characteristics re shown in Table 1. Twenty-six percent of the patient population ad diabetes and 78% of the lesions were complex (B2 or C type). n addition, 19% of the lesions were bifurcational and 7.9% were otal occlusions. All patients had successful PES implantation, and here was no angiographic evidence of any residual dissection after ES implantation. The mean stent per lesion ratio was 1.23, and lycoprotein IIb/IIIa inhibitors were used in 40% of the patients. To date, all 977 patients have completed 6 months from the ndex procedure. At a mean follow-up of 10.5 3.6 months, the ates of target lesion revascularization, target vessel revascularizaion (TVR) and major adverse cardiac events (death, myocardial nfarction, or TVR) were 7.2%, 10.3%, and 11.4%, respectively. A ollow-up coronary angiogram was obtained in 576 patients (59%) 747 lesions), and in 201 patients (35%) the angiogram was linically driven.Among these, ISR was identified in 81 patients nd 98 lesions. The mean baseline reference vessel diameter was .60 mm. Mean baseline lesion length was 14.10 10.12 mm, and I estenotic lesion length was 9.96 6.07 mm (range 2.18 to 26.18 m), which corresponds to 29% reduction. Restenosis was found in the body and the edges in 71 lesions 72%), in the edges only in 16 lesions (16%), and in the body of the tent only in 11 lesions (11%). A schematic representation of the atterns of ISR is shown in Figure 1. The pattern of ISR in 49 esions (50%) was focal ( 10 mm in length) or multifocal (12% of he focal lesions). In the remaining 49 lesions (50%), the pattern of able 1. Baseline Demographics, Lesion and Procedural haracteristics, and Preand Post-Intervention Angiographic nalysis