Efficacy and safety of endovascular treatment with or without intravenous alteplase in acute anterior circulation large vessel occlusion stroke: a meta-analysis of randomized controlled trials

Is endovascular treatment alone as effective and safe as that with preceding intravenous thrombolysis for acute ischemic stroke? A meta-analysis of randomized controlled trials

INTRODUCTION

This meta-analysis aimed to evaluate the safety and efficacy of direct endovascular therapy (EVT) and bridging therapy (EVT with preceding intravenous thrombolysis i.e. IVT), in acute anterior circulation, large vessel occlusion stroke.

EVIDENCE ACQUISITION

Following the PRISMA guidelines, a systematic literature review of the English language literature was conducted using PubMed, Cochrane CENTRAL, SCOPUS and ClinicalTrials.gov. Outcomes of interest were measured by the modified Rankin Scale (mRS), and included: no disability (mRS0), no significant disability despite some symptoms (mRS1), slight disability (mRS2), moderate disability (mRS3), moderately severe disability (mRS4), severe disability (mRS5), mortality (mRS6). Additionally, we inspected patients having excellent outcome, functional independence outcome, and poor outcome, along with successful reperfusion and intracranial hemorrhage. We calculated pooled risk ratios (RRs) and their corresponding 95% confidence intervals (CI).

EVIDENCE SYNTHESIS

A total of seven RCTs involving 2,392 patients were finally included. The chances of achieving successful reperfusion were significantly more with IVT+EVT as compared to EVT alone (RR: 0.97; 95% CI: 0.94, 1.00; P=0.03) (I2=0%). There was no significant difference in the number of patients having outcomes ranging from mRS0 to mRS6, excellent outcome, functional independence, poor outcome or incidence of intracranial hemorrhage, who underwent either EVT alone or IVT+EVT.

CONCLUSIONS

Additional trials are needed to determine if the absence of significant differences is due to insufficient sample size or if the combination therapy is truly not beneficial.

Clinical evidence comparing bridging and direct endovascular thrombectomy: progress and controversies

Clinical evidence comparing bridging endovascular thrombectomy (bEVT) with intravenous thrombolysis and direct endovascular thrombectomy (dEVT) without thrombolysis for patients with acute ischemic stroke (AIS) presented directly to an EVT-capable center is overwhelming but inconsistent. This study aimed to analyze the progress and controversies in clinical evidence based on current meta-analyses. Three databases, including MEDLINE, EMBASE, and the Cochrane Library, were searched. Relevant data were extracted and reviewed from the pooled studies. The Assessment of Multiple Systematic Review (AMSTAR-2) was used for quality assessment. Twenty-five meta-analyses were finally included. There were 56% (14/25) from Asian countries, 20% (5/25) from North America, and 24% (6/25) from Europe. The majority (72%, 18/25) of evidence arose in a short period from 2020 to 2022 with the serial publication of four randomized controlled trials (RCTs). Among the 25 meta-analyses, 11 pooled at least three RCTs but there is substantial overlap among seven (five recruited the same four RCTs solely and two recruited the same three RCTs solely). Meanwhile, quality rating based on AMSTAR-2 showed 16 'high' rated studies (64%). For functional independence, 40% (10/25) of studies favored bEVT and 60% showed neutral results. For symptomatic intracerebral hemorrhage, most studies (82.6%, 19/23) showed no significant difference. Non-RCT studies contributed to evidence favoring bEVT. Current RCTs provide an update of clinical evidence comparing bEVT and dEVT. However, they simultaneously contribute to an unnecessary overlap among studies. Contemporary observational studies demonstrated different but possibly confounded evidence. Thus, this issue still requires more clinical evidence under standard procedures.