第58届ACC会议对新型支架进行了专篇报道，给介入医生带来了新的思索。新型支架的原理为通过吸附人体自身的循环干细胞，使之在支架表面形成保护层。但目前研究人员认为试验数据还不足以证明新型支架在用于加速心脏病患者动脉愈合方面的有效性。

    在Genous支架与铬钴合金支架分别治疗ST段抬高心肌梗死（GENIUS-STEMI）的对比试验中，研究人员评估了新型支架减少靶血管再狭窄和支架内血栓的能力，但是结果却显示其再狭窄率和支架内血栓发生率均比第三代金属裸支架高。担任Masaryk医院和J.E. Purkyne大学心脏病学副教授和主席的Pavel Cervinka博士指出，“基于单中心的小型试验结果，我们必须谨慎对待。然而，在头对头比较中，铬钴合金支架6个月的随访结果却优于Genous支架。”

    GENIUS-STEMI研究通过连续入选100例ST段抬高心肌梗死（STEMI）患者，随机将患者等分成Genous EPC（内皮祖细胞）捕获支架植入组和铬钴合金支架植入组。Genous支架通过涂有一种抗体，Genous支架吸附循环血中的EPCs，其目的是克服药物洗脱支架晚期支架内血栓的同时降低再狭窄风险。当动脉损伤时EPCs会反应性升高，并能分化成成熟的血管内皮细胞，正如动脉的内表面。人们期望这一特性可以加速愈合过程，防止血栓形成，并尽量减少动脉支架内狭窄。既往非随机化研究和临床注册研究的数据已显示出其客观的一面。

    在随访期间，研究人员通过分析患者临床资料以及冠脉造影和血管内超声超声结果，发现两组间30天的主要心脏不良事件（MACE，如心脏病发作、心源性死亡、靶病变重建）的发生率相当。而6个月时，Genous支架组的MACE发生率显著高于铬钴合金支架组（24% vs.10%，P=0.03）；Genous支架组患者的原靶病变再治疗率也显著高于铬钴合金支架组（14% vs.4%，P=0.04 ）。血管内超声显示，Genous支架内有大量的组织过度增生，是最常见的再狭窄原因，但差异并无统计学意义。此外，Genous支架组有3例患者发生晚期支架内血栓（6%），但铬钴合金支架组尚无一例。研究人员认为应谨慎对待同铬钴合金支架相比的结果，并表示患有急性心脏病的患者使用Genous EPC捕获支架是可行及安全的。

    Cervinka教授呼吁到“Genous支架的晚期支架内血栓问题着实令人不安，因此，在推广这些成果前还需要大型随机试验来最终解决该难题。”

（任芳 吕树铮  首都医科大学附属北京安贞医院）
 

英文原文：

LACKLUSTER SHOWING FOR NOVEL STENT IN HEART ATTACK STUDY
Researchers Call for Larger Trial to Test Unique Approach to Preventing Restenosis，Late Stent Thrombosis

Orlando， FL–Researchers are blaming the inadequate size of the trial for new data that did not prove the effectiveness of a novel stent designed to speed arterial healing in heart attack patients by attracting the body’s own circulating stem cells to create a protective layer over the implanted device， according to research presented during the i2 Summit the American College of Cardiology’s 58th annual scientific session

In the Randomized Comparison of Genous Stent Versus Chromium-Cobalt Stent for Treatment of ST-Elevation Myocardial Infarction(GENIUS-STEMI)trial，researchers evaluated the investigational stent’s ability to reduce both renarrowing (restenosis)of the treated artery and blood clot formation on the stent (stent thrombosis).Instead， the study demonstrated increased rates of both， when compared to a third-generation bare-metal stent.

“The results have to be interpreted cautiously because this is a small， single-center study，” said Pavel Cervinka， M.D.， Ph.D， an associate professor and head of cardiology at Masaryk Hospital and University of J.E. Purkyne， ústínad Labem， Czech Republic. “However， in a head-to-head comparison， the chromium-cobalt stents were doing better than the Genous stent at six month follow-up.”

For the GENIUS-STEMI study，100 consecutive patients with a type of heart attack known as ST-elevation myocardial infarction(STEMI)were studied. Equal numbers of patients were randomly assigned to undergo stenting with the Genous EPC(endothelial progenitor cells) capture stent or a chromium-cobalt stent.

The Genous stent is designed to reduce the risk of restenosis while overcoming the tendency toward late stent thrombosis that has shadowed drug-eluting stents. Coated with an antibody， the Genous stent attracts circulating EPCs. These EPCs are naturally elevated in response to arterial injury and have the capacity to differentiate into mature endothelial cells， like those lining the inner surface of arteries.It is hoped that this unique characteristic will accelerate the healing process，protect against blood clot formation，and minimize restenosis in stented arteries. Previous data from non-randomized studies and clinical registries have been promising.

During follow-up，researchers evaluated the patients clinically as well as with angiographic imaging and intravascular ultrasound.They found that at 30 days，the combined rate of major adverse cardiac events(MACE)—defined as heart attack，cardiovascular death，and repeat treatment of the target lesion—was comparable in the two groups.At six months，however，there was a significantly higher MACE rate among patients treated with the Genous stent when compared with those treated with the chromium-cobalt stent(24 percent vs.10 percent;p=0.03). Patients treated with the Genous stent also had a statistically higher rate of repeat procedures in the originally targeted lesion(14 percent vs.4 percent;p=0.04).
Intravascular ultrasound showed larger amounts of tissue overgrowth，the most common cause of restenosis，inside the Genous stent，although the difference was not statistically significant.In addition，there were three cases of late stent thrombosis in patients treated with the Genous stent (6 percent)，but none in patients treated with the chromium-cobalt stent.

The researchers concluded that use of the Genous EPC capture stent in patients suffering from an acute heart attack is feasible and safe，while expressing caution over the unfavorable results compared to the chromium-cobalt stent.
“The rate of late stent thrombosis in the Genous group is worrisome，”Cervinka said.“Before generalizing these results，a large randomized trial is needed to finally address this issue.”