Distal versus proximal guide catheter placement on the safety and efficacy of mechanical thrombectomy for acute ischemic stroke in anterior circulation: A systematic review and meta-analysis

BackgroundGuide catheter (GC) placement, whether distal or proximal, may influence the efficacy and safety of mechanical thrombectomy (MT) for acute ischemic stroke (AIS) due to large vessel occlusion (LVO). However, definitions of placement and procedural strategies vary across studies, limiting clarity.MethodsWe systematically searched PubMed, Embase, Scopus, and Web of Science from inception to September 1, 2024. Comparative studies of adult patients with anterior circulation AIS-LVO undergoing MT that reported GC placement were included. Both balloon GCs (BGCs) and non-BGCs were eligible. Data were pooled using random-effects models in R. Outcomes included functional independence (modified Rankin Scale 0-2 at 90 days), successful reperfusion (modified thrombolysis in cerebral infarction ≥2b or expanded thrombolysis in cerebral infarction ≥2c), first-pass recanalization (FPR), mortality, puncture-to-recanalization (PTR) time, and complications. Subgroup analyses were performed by thrombectomy technique and catheter type.ResultsSeven retrospective studies comprising 2148 patients (1042 proximal, 1106 distal) were analyzed. Distal placement was associated with higher rates of functional independence (risk ratio (RR): 1.25, 95% confidence interval (CI): 1.10-1.42), successful reperfusion (RR: 1.13, 95% CI: 1.04-1.22), and FPR (RR: 1.35, 95% CI: 1.15-1.58), as well as lower 90-day mortality (RR: 0.52, 95% CI: 0.28-0.82). PTR time was shorter with distal placement (mean difference: -7.7 min, 95% CI: -10.8 to -4.6). No significant differences were observed for symptomatic intracranial hemorrhage (RR: 0.96, 95% CI: 0.55-1.65) or emboli to new territory (RR: 0.84, 95% CI: 0.28-2.52). Benefits were consistent across both BGCs and non-BGCs. Heterogeneity existed in outcome definitions and techniques, and publication bias could not be excluded.ConclusionsDistal GC placement is associated with improved reperfusion, efficiency, and functional outcomes in MT for anterior circulation AIS-LVO, without increased complications. Given the retrospective nature of included studies, anatomic confounding, and inconsistent outcome definitions, findings should be considered preliminary. Multicenter trials are needed to confirm whether catheter position independently predicts MT outcomes.