P123 Intracerebral arterial blood pressure in the vasculature distal to large vessel occlusions in ischemic stroke patients – correlation with clinical and imaging parameters

<h3>Introduction</h3> Mechanical thrombectomy has been established as a highly-effective therapy for acute ischemic stroke (AIS) caused by a large vessel occlusion (LVO). However, our understanding of the pathophysiology of AIS is still limited, particularly regarding the microenvironment of the ischemic tissue distal to the clot. <h3>Aim of Study</h3> To assess the relationship between intracranial blood pressure and clinical parameters. <h3>Methods</h3> In this monocentric, prospective study, intracerebral blood pressures (BP) proximal and distal to the occluding clot were measured during thrombectomy in patients with AIS caused by LVO. BPs were correlated with clinical data and imaging parameters using Spearman’s rank correlation and linear regression. <h3>Results</h3> 25 patients with a mean age of 76 years were included. A positive correlation was found between the mean arterial pressure (MAP) distal to occlusion and the baseline ASPECTS (p=0.012, r=0.603, 95%-CI=0.157;0.844) in patients with anterior circulation AIS. No significant correlation was observed between the MAP distal to occlusion and collateral scores (e.g., MAP vs. ASITN/SIR score (p=0.440, r=0.194, 95%-CI=-0.314;0.615). Systemic BP did not correlate with the MAP distal to the clot (p=0.899, R²&lt;0.001, 95%-CI=-0.676;0.764) but with the MAP in the artery proximal to occlusion (e.g., p&lt;0.001, R²=0.441, 95%-CI=0.315;0.939). <h3>Conclusion</h3> The intracerebral BP measured in the ischemic tissue distal to the LVO in AIS patients correlates with the extent of the ischemic core (i.e., ASPECTS), but not with collateral scores or systemic BPs. These results support the theory of impaired autoregulation in ischemic tissue and shed light on the pathophysiology of the BP mechanisms in AIS.