Abstract TP157: A Systematic Review And Meta-analysis Of Mechanical Thrombectomy In Acute Basilar Artery Stroke

Background: The evidence for mechanical thrombectomy in posterior circulation strokes is unclear. This systematic review and meta-analysis will summarise the available evidence for the use of mechanical thrombectomy in acute basilar artery occlusion. Objectives: To assess the effect of mechanical thrombectomy in acute basilar artery occlusion on disability, mortality, reperfusion and adverse events compared to best medical treatment (BMT). Search: We conducted a systematic review of randomised and prospective, clinically controlled trials using MEDLINE and EMBASE. We reviewed the Cochrane Central Register of Controlled Trials (CENTRAL), grey literature sources and reviewed the reference lists of key papers. No time limits or language restrictions were used. We used the modified Cochrane Collaboration tool to assess the risk of bias for randomised controlled trials and the The Risk Of Bias In Non-randomized Studies of Interventions (ROBINS-I) tool for prospective non-randomised clinical trials. Results: Five studies met the inclusion criteria (n = 1416). Three were cohort studies and two were randomised controlled trials. We used the random-effects model to combine the data. We found better functional outcome (mRS 0-3, 1.90 [1.07-3.35] p=0.03) and a trend towards decreased mortality (0.75 [0.62-0.91], p= 0.003) in the mechanical thrombectomy (MT) group. The improved outcomes were in the context of significant statistical heterogeneity driven by the difference in methodology between the trials. The improved outcomes were seen in the cohort studies. No significant difference in disability or mortality were found in the randomised controlled trials. We found higher reperfusion rates (TICI 2b/3: 4.75 [1.70-13.28] p=0.003) in the mechanical thrombectomy group with higher rates of symptomatic intracranial bleeding (3.90 [1.03-14.79] p=0.04). Conclusions: Our study reflects the complex nature of posterior circulation strokes and the lack of large randomised controlled trials in this field. We did find a trend towards better mortality and functional outcomes in the included cohort studies but this was not reflected in the randomised controlled trials. We also found higher reperfusion rates in the intervention groups with higher levels of sICH.