Endovascular thrombectomy or bridging therapy in minor ischemic stroke with large vessel occlusion

Abstract

Background: Whether direct endovascular thrombectomy (EVT) is non-inferior to bridging therapy (intravenous thrombolysis [IVT] followed by EVT) in minor acute ischemic stroke due to large vessel occlusions (AIS-LVO) is not clear. Therefore, this study aimed to assess whether direct EVT is non-inferior to bridging therapy in minor AIS-LVO.

Methods: 903 patients with acute ischemic stroke due to large vessel occlusion and National Institutes of Health Stroke Scale (NIHSS) score <6 receiving EVT treatment were enrolled at Bigdata Observatory Platform for Stroke of China in China from January 1, 2019, to December 31, 2020, with final follow-up on March 31, 2021. The primary efficacy endpoint was a favorable outcome defined as a modified Rankin Scale score of 0 to 2 at three months. In addition, there were three prespecified secondary efficacy endpoints, including symptomatic intracerebral hemorrhage (ICH), in-hospital mortality, and mortality by month 3.

Results: A total of 662 patients treated with direct EVT (age 65.9 ± 10.5 years, 71.5 % male, NIHSS score 2.4 [standard deviation {SD}. 1.8]) were compared to 241 bridging-treated patients (age 65.7 ± 10.8, 75.9 % female, NIHSS score 2.5 [1.8]). The rate of symptomatic ICH in the EVT group was lower than in the bridging group (4.2 % vs. 8.3 %; P = 0.02). The in-hospital mortality was not different between the two groups (EVT vs. bridging group: adjusted hazard ratio {HR}, 0.9 [95 % confidence interval {CI}, 0.5 to 1.9]; P = 0.93). There was no significant difference in 3-month poor functional outcome rate (EVT vs. bridging group: 17.1 % vs. 16.2 % [absolute difference, 0.9 % {95 % CI, -0.8 % to 2.4 %}, P = 0.75; adjusted hazard ratio {HR}, 1.0 {95 % CI, 0.6 to 1.7}, P = 0.83]) and mortality rate (13.0 % vs. 11.2 % [absolute difference, 1.5 % {95 % CI, -3.9 % to 6.8 %}, P = 0.47; adjusted HR, 1.1 {95 % CI, 0.8 to 1.9}, P = 0.55]) between those two groups.

Conclusion: Among patients with minor AIS-LVO, direct EVT, compared with bridging therapy, met the prespecified statistical threshold for noninferiority for the 3-month prognosis.

Keywords: Endovascular thrombectomy; Intravenous thrombolysis; Large vessel occlusion; Minor ischemic stroke.