Endovascular Thrombectomy vs Best Medical Management for Late Presentation Acute Ischaemic Stroke with Large Vessel Occlusion Without CT Perfusion or MR Imaging Selection: A Systematic Review and Meta-Analysis.

BACKGROUND: The efficacy and safety of endovascular thrombectomy (EVT) beyond 6 hours from stroke onset for patients with large vessel occlusion (LVO) selected without CT perfusion(CTP) or MR imaging(MRI) is undetermined. We conducted a systematic review and meta-analysis of the current literature comparing outcomes for late presenting patients with LVO treated by best medical management (BMM) with those selected for EVT based only on non-contrast CT(NCCT)/CT angiography(CTA) (without CTP or MRI).

METHODS: PRISMA guidelines were employed. The primary outcome was functional independence (modified Rankin Scale 0-2) at 3 months. Secondary outcomes were symptomatic intracranial haemorrhage (sICH) and mortality at 3 months. Data were analysed using the random-effects model.

RESULTS: Six studies of 2083 patients, including three randomised controlled trials, were included; 1271 patients were treated with EVT and 812 patients with BMM. Compared to BMM, patients treated with EVT demonstrated higher odds of achieving functional independence (39.0% EVT vs 22.0% BMM; OR=2.55, 95%CI 1.61-4.05,p<0.0001, I2 =74%). The rates of sICH (OR=2.09, 95%CI 0.86-5.04,p=0.10) and mortality (OR=0.62, 95%CI 0.35-1.10,p=0.10) were not significantly different between each cohort.

CONCLUSION: Compared to BMM, late presenting stroke patients selected for EVT eligibility with NCCT/CTA only and treated with EVT achieved significantly higher rates of functional independence at 90 days, without increasing the incidence of sICH or mortality. Whilst these findings indicate that NCCT/CTA only may be used for EVT eligibility selection for patients who present beyond 6 hours from stroke onset, the results should be interpreted with caution due to the substantial heterogeneity between studies.