First-Line Contact Aspiration vs Stent Retriever for Proximal Occlusion in Acute Ischemic Stroke: A Systemic Review and Meta-Analysis

Introduction: The aim of this systematic review and meta-analysis was to compare the performance of first-line contact aspiration (ASP) and stent retriever (SR) in acute ischemic stroke caused by proximal large vessel occlusion. Methods: Cochrane databases, MEDLINE and EMBASE were systematically searched for literatures reporting outcomes on thrombectomy with both first-line aspiration and first-line stent retriever in proximal occlusion. Results: Thirteen studies with a total of 1614 patients were included. No differences were identified between the SR and ASP groups in terms of final reperfusion rate (modified thrombolysis in cerebral infarction 2b/3) (OR: 1.54, 95% CI: 0.88-2.70), complete recanalization rate (modified thrombolysis in cerebral infarction 3) (OR: 1.78, 95% CI: 0.58-5.44), and favorable outcomes (modified Rankin scale <= 2) (OR: 1.02, 95% CI: 0.79-1.32). With regard to adverse events, emboli to new territories (OR: 0.81, 95% CI: 0.31-2.14), intracranial hemorrhage (OR: 0.71, 95% CI: 0.40-1.28), 90-days mortality (OR: 1.02, 95% CI: 0.71-1.47) were similar between groups, while symptomatic intracerebral hemorrhage (OR: 0.43 95% CI: 0.21-0.86) was less seen in ASP. Subgroup analysis indicated that ASP was comparable to stent retriever with local aspiration (SRLA) (OR: 1.25 95% CI: 0.25-6.22) and superior to stent retriever alone (OR: 1.85 95% CI: 1.22-2.81). Moreover, in posterior circulation, contact aspiration achieved a significantly higher reperfusion (OR: 1.97 95% CI: 1.03-3.76) compared to stent retriever, and needed relatively less rescue therapies (21.5% vs 29.6%, p < 0.05). Conclusion: Our study suggested that contact aspiration might be advantageous over stent retriever alone and more suitable in posterior circulation. While ASP and SRLA thrombectomy were equally effective in achieving good clinical outcomes. However, further studies are needed to confirm these results.