One year after implantation, the zotarolimus-eluting coronary stent was found to be noninferior to the everolimus-eluting stent in preventing target-lesion failure, according to a study published online June 16 in the New England Journal of Medicine.

This “new-generation” stent was tested in a large population who had a mix of traits usually excluded from randomized clinical trials of stents, including multivessel intervention, small-vessel disease, long lesions, bifurcations, or trifurcations. “Therefore, we consider that our findings are highly generalizable to patients in everyday clinical practice,” said Dr. Patrick W. Serruys of Erasmus University Medical Center, Rotterdam, and his associates.

In the multicenter open-label study, sponsored by Medtronic CardioVascular, maker of the zotarolimus-eluting stent, patients were randomly assigned to undergo percutaneous coronary intervention (PCI) with placement of either zotarolimus-eluting (1,140 patients with 1,661 lesions) or everolimus-eluting stents (1,152 patients with 1,705 lesions). Patients were followed by telephone or hospital visit at 1, 6, and 12 months, and will continue to be followed annually for 5 years.

The primary end point was target-lesion failure at 1 year, defined as a composite of death from cardiac causes, MI, or target-lesion revascularization. This occurred in 8.2% of patients who received zotarolimus-eluting stents and 8.3% of those who received everolimus-eluting stents, a nonsignificant difference.

The zotarolimus-stent group had significantly reduced rates of death from any cause while they were hospitalized (0.1% vs. 0.8%) and at 30 days (0.2% vs. 0.9%), compared with the everolimus-stent group. However, the 1-year mortality from any cause was 1.6% in the zotarolimus group and 2.8% in the everolimus group, which was a nonsignificant difference, the investigators said (N. Engl. J. Med. 2010 June 16 [10.1056/NEJMoa1004130]).

These results remained consistent across all subgroups of patients. At least one off-label criterion was present in the majority (66.3%) of the patients.

The rate of definite stent thrombosis was significantly higher in the zotarolimus group (1.2%) than the everolimus group (0.3%).

A smaller percentage of patients than expected underwent angiographic assessment of in-stent stenosis. In-stent stenosis was worse in the zotarolimus group but still met the criterion for noninferiority, Dr. Serruys and his colleagues said.

The rates of adverse events were low and compared favorably with those in previous studies, with no significant between-group differences, they added.

“Although our findings are hypothesis generating and require additional investigation, definitive conclusions will be obtained only from longer-term follow-up in large patient populations in studies that have sufficient statistical power to detect differences in rates of stent thrombosis,” the researchers said.

Dr. Serruys and several of his associates reported ties to Medtronic Inc., which sponsored the study, Boston Scientific Corp., and to Abbott Labs, the maker of the everolimus-eluting stent used in this study. These comprised consultancy and grants to their institutions. Two of the authors are full-time employees of Medtronic.

Copyright (c) 2009 Elsevier Global Medical News. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.

据《新英格兰医学杂志》6月16日在线发表的一项研究，支架植入1年后，在防止靶病变失败方面，佐他莫司洗脱冠状动脉支架不劣于依维莫司洗脱支架。

 

此“新一代”支架试验的大样本群体纳入了一般随机临床试验所除外的一些情况，包括多血管介入、小血管病变、长病变、两支或多支病变。鹿特丹伊拉斯姆斯大学医学中心的Patrick W. Serruys博士及其同事们说：“因此，我们认为，我们的发现对于日常临床实践中的患者非常适用。”

 

在这项由佐他莫司洗脱支架制造者美敦力公司血管事务部主办的多中心开放性研究中，患者们接受经皮冠状动脉介入(PCI)治疗时，随机放置佐他莫司(1,140例患者1,661处病变)或依维莫司(1,152例患者1,705处病变)洗脱支架，随后分别在第1、6、12个月接受电话随访或者医院内调查，在未来的5年里还要每年接受1次随访。

 

此研究的主要终点是1年靶病变失败率，即由心源性死因、心肌梗死(MI)或者靶病变血运重建组成的复合终点。佐他莫司洗脱支架组上述终点的发生率是8.2%，依维莫司洗脱支架组发生率是8.3%，差异无统计学意义。

 

研究者报道说，与依维莫司洗脱支架组相比，佐他莫司洗脱支架组在住院期间(0.1% 对 0.8%)及术后30天(0.2% 对 0.9%)的全因死亡率显著降低；但是，佐他莫司组的1年全因死亡率是1.6%，依维莫司组是2.8%，差异没有统计学意义[N. Engl. J. Med. 2010 June 16 (10.1056/NEJMoa1004130)]。

 

此结果在所有患者亚组中保持一致。多数(66.3%)患者至少存在一种超适应证应用。

 

在明确的支架内血栓形成率方面，佐他莫司组(1.2%)比依维莫司组(0.3%)显著增高。

 

Serruys博士及其同事们说，比预期百分比稍低一些的患者接受了支架内狭窄的血管造影检查。佐他莫司组的支架内狭窄更严重，但仍然符合非劣效性标准。

 

不良事件的发生率较低，且与既往研究相比毫不逊色，两组间差异没有显著性，他们补充说。

 

研究者们说：“尽管我们的发现只是产生假设，需要更多调查研究，但只有通过对大样本患者群体进行更长时间的随访研究，得到足够的统计学证据来显示血栓形成率的差异后，才能得出明确的结论。”

 

Serruys博士及其几位同事报告说，此研究与美敦力公司(研究主办方)、波士顿科学公司、本研究所用的依维莫司洗脱支架制造商雅培公司存在关系。这些公司为他们的机构提供顾问及资金支持。其中有两个作者是美敦力公司的全职员工。

 

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