BACKGROUND A novel stent retriever device with an enhanced radial force profile, enlarged offset openings, and a closed distal end has been developed. OBJECTIVE Evaluate the safety and effectiveness of the NeVaTM thrombectomy device in animal model of thrombo-occlusive disease. MATERIALS AND METHODS Seven swine were used in safety and efficacy studies. Thrombo-occlusive disease was modeled using 4 emboli morphologies; 2 distinct models of autologous whole blood thrombi, plasma-enriched thrombi, and Onyx® emboli. A total of 35 vascular occlusions and retrievals were performed using emboli of variable sizes. Pre- and post-modified thrombolysis in cerebral ischemia (mTICI) scores, number of retrievals, and the presence of angiographic complications were recorded. In the safety study, a total of 6 clot retrievals were completed and the vascular territory examined grossly and harvested for histopathological evaluation. A semiquantitative vasospasm study was performed. Radial force testing was performed on NeVaTM and control devices for comparison. RESULTS Near-full or full reperfusion (mTICI 2b/3) was achieved in 34/35 occlusions after a mean of 1.2 passes. Full reperfusion (TICI 3) was achieved in 17/17 of whole blood clot occlusions (ranging between 10 and 20 mm) after a mean of 1.06 passes. The rate of mTICI 2b/3 reperfusion was 10/11 (mean, 1.6 passes) and 5/5 (mean, 1.0 passes) for Onyx® and plasma-enriched clot emboli, respectively. Histopathological vessel injury and vasospasm scores were comparable to predicate studies. Radial force curves demonstrated increased expansive radial force and similar compressive radial force compared to predicate devices. CONCLUSIONS Our preclinical results support the use of the NeVaTM device in a clinical trial to determine if this novel design improves upon current stent retriever outcomes.

中文翻译：

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NeVaTM 支架回收器的临床前评估：猪血栓切除模型的安全性和有效性。

背景技术已经开发了一种具有增强的径向力分布、扩大的偏置开口和封闭的远端的新型支架取回器装置。目的评价NeVaTM取栓装置在血栓闭塞性疾病动物模型中的安全性和有效性。材料和方法 七头猪用于安全性和有效性研究。使用 4 种栓子形态对血栓闭塞性疾病进行建模；2 种不同的自体全血血栓、富含血浆的血栓和 Onyx® 栓子模型。使用不同大小的栓子进行了总共 35 次血管闭塞和修复。记录改良前和后脑缺血溶栓（mTICI）评分、取出次数和血管造影并发症的存在。在安全研究中，总共完成了 6 次血凝块回收，对血管区域进行了大体检查并收获用于组织病理学评估。进行了半定量血管痉挛研究。在 NeVaTM 和控制装置上进行径向力测试以进行比较。结果 在平均 1.2 次通过后，在 34/35 的闭塞中实现了接近完全或完全再灌注 (mTICI 2b/3)。在平均 1.06 次通过后，17/17 的全血凝块闭塞（范围在 10 和 20 毫米之间）实现了完全再灌注 (TICI 3)。Onyx® 和富含血浆的血栓栓塞的 mTICI 2b/3 再灌注率分别为 10/11（平均，1.6 次通过）和 5/5（平均，1.0 次通过）。组织病理学血管损伤和血管痉挛评分与谓词研究相当。与谓词装置相比，径向力曲线显示出增加的膨胀径向力和类似的压缩径向力。结论 我们的临床前结果支持在临床试验中使用 NeVaTM 装置，以确定这种新颖的设计是否能改善当前支架取栓器的结果。