ABSTRACT NUMBER: ESOC2026A2192 DIFFERENCES IN CEREBRAL AUTOREGULATION DURING AND AFTER ENDOVASCULAR TREATMENT OF ACUTE LARGE-VESSEL OCCLUSIONS

Abstract Background and aims Large-vessel occlusions (LVOs) causing acute ischemic stroke can be recanalized by endovascular treatment (EVT) effectively altering patient outcome. Protection by cerebral autoregulation (CA) against hypo- and hyperperfusion is well-functioning in healthy individuals but is impaired in the affected hemisphere after EVT. However, CA assessments with transcranial Doppler are not feasible during EVT. Therefore, we examined cortical oxygenated hemoglobin concentration (OxyHb) with near-infrared spectroscopy and analyzed CA through very low-frequency oscillations (VLFO ~ 0.05Hz) in OxyHb. Methods We enrolled LVO patients treated with EVT under general anaesthesia and measured prefrontal OxyHb (Octamon, Artinis) before, immediately after reperfusion and at 24-hour follow-up. We applied transfer function analysis between VLFOs of OxyHb in ischemic and contralateral hemispheres yielding CA measures of amplitude ratio (gain) and temporal dyssynchronization (phase shift). Results Sixty-five of 100 examined LVO patients had sufficient data. Patients (41.5% female) were 73.0 years old (IQR 61.0-81.0) with a median baseline NIHSS of 15.5 (IQR 11.0-21.0). Successful perfusion (mTICI≥2b) was re-established in 93.8%. Independent 90-day outcome (mRS 0-2) was 47.7% and 90-day mortality was 13.8%. VLFO gain was lower in middle cerebral artery (1.05, IQR 0.93-1.17) regions compared to anterior cerebral artery (0.85, IQR 0.61-1.25) regions (p=0.001). VLFO phase shift was stable throughout for 90-day survivors (-2.8, SD 21.7). In non-survivors, VLFO phase shift was lower before recanalization but increased progressively both after recanalization and at 24-hour follow-up (p=0.002). Conclusions Cerebral autoregulation in LVO patients showed regional intrahemispherical differences and progressive disturbance during EVT in non-survivors but stability in survivors. Conflict of interest Adam Vittrup Heiberg: nothing to disclose