Endovascular Thrombectomy for Large Core Volume Acute Ischemic Stroke. Updated Systematic Review and Meta-Analysis: Thrombectomy for large core acute ischemic strokes

Abstract

Background: Several recent studies assessed the efficacy and safety of endovascular thrombectomy (EVT) for patients with acute ischemic stroke caused by an anterior circulation large vessel occlusion (LVO) with large core infarct volumes.

Methods: We performed a systematic review and meta-analysis from inception until July 2024 of all randomized clinical trials (RCTs) and observational studies to date comparing the efficacy and safety of EVT plus best medical management (MM) for acute ischemic stroke due to anterior circulation LVO with large core, versus MM alone. Primary efficacy outcome was optimal functional outcome defined by a 90-day modified Rankin scale score (mRS) of 0-2. Safety outcomes were risk of symptomatic intracranial hemorrhage (sICH) and 90-day mortality. Subgroup analyses were done by study design. Relative risk (RR) and 95 % CIs were calculated using random-effects models and heterogeneity was assessed by I² statistics.

Results: A total of 16 studies with 3,717 participants met inclusion criteria (6 RCTs and 10 observational studies). The quality of the evidence was moderate to high. Compared with MM alone, EVT increased the outcome of mRS 0-2 (RR = 2.91, 95 % CI [2.12, 4.01], I² = 63 %), decreased mortality (RR = 0.75 [0.63, 0.88], I² = 60 %), but did not influence the risk of sICH (I² = 14 %). When the analysis was restricted to data from RCTs (n = 1,887), EVT increased the outcome of mRS 0-2 (RR = 2.50 [1.89, 3.29], I² = 8 %) and sICH (RR = 1.71 [1.09, 2.66], I² = 0 %) but did not affect mortality (I² = 45 %). In observational studies (n = 1,830), patients receiving EVT had a higher likelihood of achieving an mRS 0-2 (RR = 3.39 [1.98-5.79], I² = 74 %), lower mortality (RR = 0.63 [1.49-0.82], I² = 50 %), but equal risk of sICH (I² = 29) than those receiving MM alone.

Conclusion: Among patients with LVO with large core infarct, EVT was associated with improved functional outcome at 90 days. When the analysis was restricted to RCTs, EVT increased the risk of sICH, but did not affect 90-day mortality. However, in real-world (observational) studies, EVT did not modify the risk of sICH but reduced 90-day mortality.

Keywords: Hemorrhagic conversion; Large core stroke; Outcomes; Thrombectomy.