Aspiration versus Stent Retriever Thrombectomy in Posterior Circulation Stroke: A Systematic Review and Meta-Analysis

The management of posterior circulation stroke is primarily carried out by endovascular approaches including aspiration or stent retrevier thrombectomy. Existing reviews have attempted to comparatively evaluate their efficacy in terms of morbidity and mortality-related outcomes, however, with several limitations. Therefore, in this review, we attempt to address the gap in the existing literature by evaluating the comparative impact of stent retriever-based and aspiration-based thrombectomy interventions in posterior circulation stroke patients on the following parameters: overall procedure duration, recanalization time, rescue therapy usage, complication risk, and mortality risk.

A systematic search of the academic literature was performed according to PRISMA guidelines across five databases. We conducted a random-effect meta-analysis to evaluate comparative outcomes, including procedural duration, time to recanalization, risk of complications, use of rescue therapy, and risk of mortality in patients with posterior circulation stroke undergoing stent retriever- and aspiration-based thrombectomies. We also performed comparative subgroup analyses to evaluate differences in outcomes between contact and manual aspiration interventions.

From 963 studies, we found nine eligible studies containing data on 840 patients. Meta-analysis revealed a large-to-medium size positive effect for stent retriever-based thrombectomy on overall procedure duration and recanalization compared to aspiration-based thrombectomy. Additional analysis revealed higher risk of complications and mortality in posterior circulation stroke patients undergoing stent retriever-based thrombectomy as compared to aspiration-based thrombectomy. We also observed that the use of rescue therapy was elevated in patients undergoing aspiration-based thrombectomy compared to stent retriever-based thrombectomy.

This study provides preliminary evidence for improved morbidity and mortality outcomes in posterior circulation stroke patients undergoing aspiration-based thrombectomies as compared to stent retriever-based thrombectomy. The study also provides evidence for improved endovascular outcomes for patients undergoing aspiration-based thrombectomies. The findings from this study can have implications in developing awareness among neurosurgeons for stratifying patients to manage posterior circulation stroke according to the risks associated with aspiration and stent retriever-based thrombectomies.