Abstract Number: Esoc2026lb116 Lb116 - Management of Systolic Blood Pressure During Endovascular Thrombectomy Under General Anaesthesia for Acute Ischaemic Stroke (Masterstroke): A Multi-Centre, Double-Blind Parallel Group, Randomised Controlled Trial

Abstract Background and aims Cerebral autoregulation is impaired in patients with large vessel occlusion (LVO) ischaemic stroke. Guidelines provide moderate-strength recommendations to maintain systolic blood pressure (SBP) between 140 and 180 mmHg during endovascular thrombectomy (EVT). Higher SBP may increase penumbral blood flow, reduce infarct size and improve outcome, whereas lower SBP may reduce haemorrhagic complications. Methods MASTERSTROKE was a double-blind, randomised-controlled trial of anterior circulation LVO patients having EVT under general anaesthesia. Participants were randomised (1:1) to intra-procedural SBP of 140±10 mmHg or 170±10 mmHg. The primary outcome was shift in modified Rankin Scale score (mRS) at day-90. Clintrials.gov (NCT05645861). Results 562 patients (287 51.0% female, mean SD age 69.6 14.5 years, median IQR NIHSS 15 11-20) were randomised to 140 mmHg (n=280) and 170 mmHg (n=282) treatment groups. Median intra-procedural SBP was 141 mmHg (135-148) and 170 mmHg (162-177). Day-90 median mRS score was 2 (1–4) in both groups (P=0.49). There were no differences in symptomatic intracranial haemorrhage (2.1% versus 2.1%; OR 0.99 95% CI, 0.32-3.12), good functional outcome (day-90 mRS 0-2, 54.9% versus 51.1%; OR 1.30 95% CI, 0.80 to 2.11; P =0.33), and day-90 mortality (12.1% versus 15.2%; OR 0.87 95%CI, 0.62-1.21; P=0.28) between the 140 and 180 mmHg groups, respectively. Conclusions This large multicentre trial is the first to test and achieve specific SBP targets during EVT. We provide class 1 evidence that there is no signal of additional benefit or harm across the 140-180 mmHg range of intra-procedural SBP recommended in current guidelines. Conflict of interest