This study aims to investigate the impact of first pass effect (FPE) on outcomes in the posterior circulation acute ischemic stroke (PC-AIS) and the independent predictors of FPE. This was a multicenter, retrospective study. PC-AIS patients who underwent endovascular treatment were reviewed. The cohort achieving complete or nearly complete reperfusion (defined as expanded treatment in cerebralischemia [eTICI] ≥ 2c) was categorized into the FPE and multiple pass effect (MPE) groups. FPE was defined as achieving eTICI ≥ 2c with a single pass and without the use of rescue therapy. Modified FPE (mFPE) was defined as meeting the criteria for FPE but with eTICI ≥ 2b. The association of FPE with 90-day clinical outcomes and predictors for FPE were both investigated. The study included a total of 328 patients, with 69 patients (21%) in the FPE group. For primary outcome, FPE had a significant higher favorable outcome (mRS ≤ 3) rate than MPE (65.2% vs. 44.8%, p = 0.003). Similar outcomes were observed in the mFPE. Furthermore, FPE was significantly associated with favorable outcome (adjusted OR 2.23, 95% CI 1.06-4.73, p=0.036). Positive predictors for FPE included occlusion in the distal basilar artery, the first-line aspiration or combination, and cardioembolic etiology. Negative predictors for FPE included hypertension and general anesthesia. For PC-AIS patients due to large or medium vessel occlusion, FPE is associated with favorable clinical outcomes. The first-line techniques of aspiration or combination, as well as avoiding general anesthesia, contribute to a better realization of FPE.

中文翻译：

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接受后循环急性缺血性卒中血管内治疗的患者的首过效应。

本研究旨在探讨首过效应（FPE）对后循环急性缺血性卒中（PC-AIS）结局的影响以及 FPE 的独立预测因子。这是一项多中心、回顾性研究。对接受血管内治疗的 PC-AIS 患者进行了回顾。实现完全或接近完全再灌注（定义为脑缺血的扩大治疗 [eTICI] ≥ 2c）的队列被分为 FPE 组和多次通过效应 (MPE) 组。FPE 被定义为在不使用救援治疗的情况下单次达到 eTICI ≥ 2c。改良 FPE (mFPE) 定义为满足 FPE 标准，但 eTICI ≥ 2b。FPE 与 90 天临床结果的关联以及 FPE 的预测因素均得到了研究。该研究总共纳入了 328 名患者，其中 FPE 组有 69 名患者（21%）。对于主要结局，FPE 的有利结局 (mRS ≤ 3) 率显着高于 MPE（65.2% vs. 44.8%，p = 0.003）。在 mFPE 中也观察到类似的结果。此外，FPE 与良好的结果显着相关（调整后 OR 2.23，95% CI 1.06-4.73，p=0.036）。FPE 的阳性预测因素包括远端基底动脉闭塞、一线抽吸或组合以及心源性栓塞病因。FPE 的负面预测因素包括高血压和全身麻醉。对于因大或中型血管闭塞而导致的 PC-AIS 患者，FPE 与良好的临床结果相关。抽吸或联合一线技术以及避免全身麻醉有助于更好地实现 FPE。