BackgroundThe Tigertriever stent retriever (Rapid Medical) can be actively expanded and contracted by the operator, which allows for several actuation-related parameters to be optimized to potentially improve device efficacy. These parameters have not yet been evaluated. We conducted a benchtop study to evaluate the effect of actuation frequency on clot integration within the stent.MethodsA Tigertriever 17 device was deployed within a biological clot analog placed in a straight tube. The device was actuated between the maximally contracted and maximally expanded states with three different frequencies: passive (one-time opening, n = 6), slow (20 s/cycle, n = 6), and fast (5 s/cycle, n = 7). A flat-detector CT scan was acquired, the clot and stent wires were segmented, and the boundaries of the clot and stent wires were calculated on each axial slice. The intersection between the stent and clot boundaries throughout the volume was defined as the volume of clot integrated within the stent. The clot integration factor (ratio of integrated clot volume to total clot volume) was then statistically compared between the three frequencies as an estimate of clot capture efficiency.ResultsThe clot integration factor was significantly higher (23% increase, p = 0.01) with the fast actuation as compared to the passive and slow actuations, with a post hoc test showing no difference ( p > 0.05) between the passive and slow groups.ConclusionsFaster actuation frequencies may result in improved clot integration with the Tigertriever device. This effect needs to be validated by clinical data.

中文翻译：

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驱动频率对 Tigertriever 装置凝块整合的影响：初步体外研究

背景 Tigertriever 支架回收器 (Rapid Medical) 可由操作员主动扩张和收缩，从而优化多个与驱动相关的参数，从而潜在地提高设备功效。这些参数尚未评估。我们进行了一项台式研究，以评估驱动频率对支架内凝块整合的影响。方法将 Tigertriever 17 装置部署在置于直管中的生物凝块模拟物内。该装置以三种不同频率在最大收缩和最大扩张状态之间启动：被动（一次性打开，n = 6）、慢速（20 s/周期，n = 6）和快速（5 s/周期，n = 7）。获取平面探测器 CT 扫描，对凝块和支架丝进行分段，并在每个轴向切片上计算凝块和支架丝的边界。整个体积中支架和凝块边界之间的交点被定义为集成在支架内的凝块体积。然后对三个频率之间的凝块整合因子（整合的凝块体积与总凝块体积之比）进行统计比较，作为凝块捕获效率的估计。结果随着快速频率的增加，凝块整合因子显着更高（增加 23%，p = 0.01）。与被动和慢速驱动相比，事后测试显示被动组和慢速组之间没有差异 (p > 0.05)。结论更快的驱动频率可能会改善与 Tigertriever 装置的凝块整合。这种效果需要临床数据来验证。