Comparison of Micro-Clamping Stent-Retriever Thrombectomy with Conventional Stent-Retriever Thrombectomy in Intracranial Large Vessel Embolism

OBJECTIVE: To evaluate the effectiveness at micro-clamping stent-retriever thrombectomy (MSRT) in patients with acute ischemic stroke with intracranial large vessel embolism (ILVE), and compare it with that of conventional stent-retriever thrombectomy (CSRT). METHODS: We retrospectively evaluated 108 patients with ILVA treated by MSRT (n = 52) or CSRT (n = 56) from the 2 participating institutions between January 2016 and November 2017. The rates of successful (Modified Thrombolysis in Cerebral Infarction [mTICI] grade 2b or 3) and complete reperfusion (mTICI grade 3), time from guide catheter placement to reperfusion, rates of first-pass success, and the number of passes for reperfusion were compared between the MSRT and CSRT groups. RESULTS: The complete reperfusion (mTICI 3) rates by MSRT were significantly higher than those achieved with CSRT (78.8% [41/52] vs. 57.1% [32/56], respectively; P = 0.016). Successful reperfusion (mTICI 2b or 3) rates were 92.3% (48/52) in the MSRT group and 83.9% (47/56) in the CSRT groups (P = 0.181). The mean number of passes for reperfusion was significantly lower with MSRT compared with CSRT (1.5 +/- 0.2 vs. 2.5 +/- 0.5, respectively; P = 0.001). The first-pass success rates were significantly higher in the MSRT group than in the CSRT group (65.4% [34/52] vs. 28.6% [16/56]; P = 0.0001). The mean time from guide catheter placement to reperfusion was significantly shorter in the MSRT group (20.5 +/- 6.6 minutes vs. 46.3 +/- 7.6 minutes; P = 0.001). CONCLUSIONS: These findings suggest that the complete reperfusion rates and mechanical thrombectomy efficiency in patients with ILVE are better after MSRT compared with CSRT.