Abstract 95: Exceeding Personalized Blood Pressure Targets After Endovascular Stroke Therapy is Associated With Hemorrhagic Transformation and Worse Functional Outcome

Abstract

Background: Effective blood pressure (BP) management after endovascular stroke therapy (EVT) is critical for maintaining optimal cerebral perfusion and to protect the brain from hyperperfusion. A single, universal BP target below 180/105 mmHg is likely inadequate in this highly heterogeneous patient population. We calculated individualized BP thresholds at which cerebral autoregulation was best preserved and analyzed how exceeding these limits correlates with hemorrhagic transformation (HT) and functional outcome. Methods: 51 patients with large-vessel occlusion (LVO) stroke who underwent EVT were prospectively enrolled. Autoregulatory function was continuously measured by interrogating changes in near-infrared spectroscopy and mean arterial pressure (MAP). The resulting autoregulatory index was used to identify and trend the BP range at which autoregulation was most preserved (Figure 1A). The percent time that MAP exceeded the upper limit of autoregulation (ULA) was calculated for each patient. HT was identified on CT imaging at 24 hours. Functional outcome was assessed using the modified Rankin Scale (mRS). Associations among percent time above ULA, HT and mRS were analyzed using ordinal or logistic regression, adjusting for age, TICI score and baseline NIHSS. Results: Personalized limits of autoregulation could be computed in 36 patients (mean age 71±15, 12 F, mean admission NIHSS 15±6, average monitoring time 26±19 hours, HT=17). Optimal BP and limits of autoregulation were calculated for 83±11% of the total monitoring period. Percentage of time with MAP above ULA was associated with HT (p=0.016, OR 1.15, 95% CI 1.02-1.29) and worse functional outcome at discharge (p<0.004, OR 1.13, 95% CI 1.04-1.22) and 90 days (p=0.003, OR 1.22, 95% CI 1.06-1.38) (Figure 1B - D). Conclusions: Non-invasive determination of personalized BP thresholds for LVO stroke patients is feasible; exceeding these limits may increase the risk of HT and worse clinical outcomes.