Safety and efficacy of aspiration thrombectomy versus stent retriever thrombectomy for acute ischaemic stroke: a systematic review and meta-analysis

Introduction
Although aspiration thrombectomy has shown comparable safety and efficacy to stent retriever thrombectomy for acute ischaemic stroke (AIS), the use of aspiration thrombectomy as first-line endovascular treatment for AIS remains controversial.

Aim
To perform a systematic evaluation of the safety and efficacy of aspiration thrombectomy versus stent retriever thrombectomy in the treatment of AIS.

Material and methods
We searched the online databases PubMed, Embase, Cochrane Library, and SinoMed to collect randomized controlled trials and retrospective studies concerning the treatment of AIS with aspiration thrombectomy and stent retriever thrombectomy. Primary outcomes included 90-day all-cause mortality, a 90-day mRS scores of 0–2, intracranial haemorrhage, and successful recanalization rate. The Jadad scale and the MINORS evaluation items were used to evaluate study quality, and RevMan 5.2 was used to conduct a meta-analysis. Any differential effects in rates between the two strategies were assessed using a random effect model.

Results
A total of 15 articles were found, including 2 randomized controlled trials and 13 retrospective studies. It showed that aspiration thrombectomy and stent retriever thrombectomy had similar results in terms of 90-day all-cause mortality (p = 0.88), 90-day mRS scores 0–2 (p = 0.29), and intracranial haemorrhage (p = 0.47). And in terms of successful recanalization rates, the aspiration thrombectomy group had better outcomes than the stent retriever thrombectomy group (p = 0.0003). The heterogeneity of 90-day all-cause mortality (I2 = 0%), 90-day mRS scores of 0–2 (I2 = 6%), intracranial haemorrhage (I2 = 21%), and successful recanalization rate (I2 = 0%) were less than 30%.

Conclusions
Both aspiration thrombectomy and stent thrombectomy can be used as the first line of intravascular treatment for AIS.