Abstract P335: Post-Treatment Blood-Brain Barrier Disruption is Associated With Cerebral Edema and Extends Into Penumbral Tissue in Anterior Circulation Large Vessel Occlusion

Abstract

Background: Blood Brain Barrier (BBB) disruption is central to vasogenic edema development after ischemia in preclinical studies. We investigated the relationship between BBB disruption and cerebral edema in patients receiving reperfusion therapies for anterior circulation large vessel occlusion. Methods: In a post-hoc pooled analysis of the Tenecteplase versus Alteplase before Endovascular Therapy for Ischemic Stroke (EXTEND-IA TNK) part 1 and 2 multicenter RCTs, the DWI lesion on 24h post-treatment MRI and peri-infarct salvaged penumbra derived from pre-treatment CT-Perfusion (CTP) were segmented and registered to 24h MR Perfusion. A validated permeability measure (percentage of measured cerebral blood volume lost due to T1 effect from gadolinium leakage across the BBB) was calculated for each ROI. The association between post-treatment BBB disruption in the infarct and cerebral edema assessed on a trichotomized ordinal scale of negligible (<1mm midline shift), mild (≥1 to <5mm) or severe (≥5mm) was analyzed using ordinal logistic regression. Results: Of 220 patients analyzed, median (IQR) BBB disruption was 2.36(1.4-4.1)% in the infarct, 1.61(1.0-2.6)% in salvaged penumbra and 0.98(0.7-1.5)% in normal brain (p<0.001). There were 119 (54.1%) patients with negligible, 90 (40.8%) mild and 11 (5.0%) severe cerebral edema at 24h. In multivariable analysis, infarct BBB disruption was associated with increased cerebral edema (cOR=1.11 per%, 95%CI 1.02-1.21;p=0.012, adjusted for age, admission NIHSS and reperfusion (mTICI2b/3 or >50% reperfusion on early CTP 2h post-lysis). Infarct BBB disruption correlated with follow-up infarct volume (rho=0.37;p<0.001), and was associated with parenchymal hematoma (aOR=1.18, 95%CI 1.00-1.40;p=0.048) and worse outcome assessed on 90-day modified Rankin Scale (cOR=1.16 per%, 95%CI 1.08-1.26;p<0.001, adjusted for age, admission NIHSS and reperfusion). Conclusions: BBB disruption after reperfusion treatment extends beyond the infarct lesion, and is associated with cerebral edema development, hemorrhagic transformation and poor outcome. Further studies to evaluate BBB integrity as an imaging biomarker and potential therapeutic target in malignant cerebral edema after ischemic stroke are needed.