Stanford University, Stanford, CA 94305, USA.
Circ Cardiovasc Interv. 2011 Jun;4(3):248-55. doi: 10.1161/CIRCINTERVENTIONS.110.957548. Epub 2011 May 17.
Polymer formulation may affect the efficacy of drug-eluting stents. Resolute, Endeavor, and ZoMaxx are zotarolimus-eluting stents with different stent platforms and different polymer coatings and have been tested in clinical trials. The aim of this analysis was to compare the efficacy of zotarolimus-eluting stents with different polymers.
Data were obtained from the first-in man trial or first randomized trials of each stent, The Clinical RESpOnse EvaLUation of the MedTronic Endeavor CR ABT-578 Eluting Coronary Stent System in De Novo Native Coronary Artery Lesions (RESOLUTE), Randomized Controlled Trial to Evaluate the Safety and Efficacy of the Medtronic AVE ABT-578 Eluting Driver Coronary Stent in De Novo Native Coronary Artery Lesions (ENDEAVOR II), and ZoMaxx I trials. Follow-up intravascular ultrasound analyses (8 to 9 months of follow-up) were possible in 353 patients (Resolute: 88, Endeavor: 98, ZoMaxx: 82, Driver: 85). Volume index (volume/stent length) was obtained for vessel, stent, lumen, peristent plaque, and neointima. Cross-sectional narrowing was defined as neointimal area divided by stent area (%). Neointima-free frame ratio was calculated as the number of frames without intravascular ultrasound-detectable neointima divided by the total number of frames within the stent. At baseline, vessel, lumen, and peristent plaque volume index were not significantly different among the 4 stent groups. At follow-up, percent neointimal obstruction was significantly lower in Resolute compared with Endeavor, ZoMaxx, and Driver (Resolute: 3.7±4.0, Endeavor: 17.5±10.1, ZoMaxx: 14.6±8.1, Driver: 29.4±17.2%; P<0.001). Greater maximum cross-sectional narrowing and higher neointima-free frame ratio, suggesting less neointimal coverage, were observed in Resolute compared with other stent groups. Multiple regression analysis confirmed that the biodurable polymer used in Resolute independently correlated with neointimal suppression among 3 zotarolimus-eluting stents.
The different polymer formulations significantly affect the relative amount of neointima for zotarolimus-eluting stents.
URL: http://www.clinicaltrials.gov. Unique identifier: NCT00248079.
聚合物配方可能会影响药物洗脱支架的疗效。Resolute、Endeavor 和 ZoMaxx 是三种载有不同药物的雷帕霉素洗脱支架，具有不同的支架平台和聚合物涂层，并已在临床试验中进行了测试。本分析的目的是比较不同聚合物的雷帕霉素洗脱支架的疗效。
数据来自每个支架的首例人体试验或首次随机试验，即经皮冠状动脉介入治疗中 Medtronic Endeavor CR ABT-578 洗脱冠状动脉支架系统的临床反应评估（RESOLUTE）、随机对照试验评估 Medtronic AVE ABT-578 洗脱司机冠状动脉支架在新发病变中的安全性和疗效（ENDEAVOR II）和 ZoMaxx I 试验。353 例患者（Resolute：88 例，Endeavor：98 例，ZoMaxx：82 例，Driver：85 例）进行了随访血管内超声分析（随访 8-9 个月）。获得了血管、支架、管腔、残留斑块和新生内膜的体积指数（体积/支架长度）。横截面狭窄定义为新生内膜面积除以支架面积（%）。无血管内超声可检测到新生内膜的帧数比除以支架内总帧数得到新生内膜无框架比。在基线时，4 个支架组之间的血管、管腔和残留斑块体积指数无显著差异。在随访时，与 Endeavor、ZoMaxx 和 Driver 相比，Resolute 的新生内膜阻塞百分比明显更低（Resolute：3.7±4.0，Endeavor：17.5±10.1，ZoMaxx：14.6±8.1，Driver：29.4±17.2%；P<0.001）。与其他支架组相比，Resolute 观察到更大的最大横截面狭窄和更高的新生内膜无框架比，表明新生内膜覆盖更少。多变量回归分析证实，Resolute 中使用的生物稳定聚合物与 3 种雷帕霉素洗脱支架中的新生内膜抑制独立相关。
不同的聚合物配方显著影响雷帕霉素洗脱支架的新生内膜量。
