Safety and Efficacy of Mechanical Thrombectomy Using Stent Retrievers in the Endovascular Treatment of Acute Ischaemic Stroke: A Systematic Review

Background: The treatment of choice for acute ischaemic stroke is the intravenous administration of recombinant tissue plasminogen activator within 3-4.5 h of symptom onset. However, the use of a thrombolytic would be limited by its narrow therapeutic window and contraindications. As a result, in recent years, techniques such as mechanical thrombectomy have emerged, which employ thrombus retrieval devices, such as stent retrievers (Solitaire™, Trevo® or Revive™), whose safety and efficacy in the endovascular treatment of acute ischaemic stroke is analysed in this article.

Methods: A systematic literature search was undertaken until March 2015. The quality of evidence was assessed according to the GRADE methodology. A meta-analysis of the results of randomised controlled trials (RCTs) was performed, and the weighted average for the case series' sample size was calculated (Review Manager v5.2 and SPSS v19).

Results: Seventeen primary studies (2 RCTs, Solitaire™ and Trevo® vs. Merci®, and 15 case series) were selected. The RCT results show that stent retrievers have a safety profile similar to the Merci® device. However, both Solitaire™ and Trevo® achieved a higher recanalisation success rate (OR, 4.56; 95% CI, 2.63-7.90; p < 0.00001) and appropriate clinical outcome at 90 days (OR, 2.54; 95% CI, 1.52-4.25; p < 0.0004), although the 90-day mortality rate was similar in both groups (OR, 0.75; 95% CI, 0.17-3.37; p = 0.70).

Conclusions: Stent retrievers appear to be safe and effective devices, achieving high recanalisation rates and good clinical outcomes in the endovascular treatment of patients with acute ischaemic stroke due to the occlusion of intracranial arteries in comparison with the clot retriever Merci®.