Abstract DP251: Post-Endovascular Thrombectomy Microvascular Perfusion and Early Blood Pressure Trajectories

Background: Endovascular thrombectomy (EVT) is the standard treatment for acute ischemic stroke with large-vessel occlusion. However, some patients still experience early neurological deterioration or poor recovery despite successful recanalization. A potential explanation is impaired microvascular perfusion (IMP), where tissue-level flow remains insufficient despite proximal recanalization. Proposed mechanisms include microthrombi formation, endothelial injury, and blood-brain barrier disruption. In the presence of IMP, cerebral perfusion may become pressure-passive and more dependent on systemic blood pressure (BP). As BP typically rises at stroke onset to preserve perfusion, post-recanalization perfusion status may influence BP dynamics. In this study, we investigated whether post-EVT perfusion status influences early BP trajectories. Methods: We retrospectively analyzed a cohort from a single tertiary center (2014–2024) with successful recanalization (eTICI >=2b) and post-EVT MRI including DSC perfusion performed within 24 h. Post-EVT IMP was defined as the presence of a region with Tmax >6s within the recanalized territory, excluding infarct core (ADC <620x10^-6 mm²/s). Longitudinal trends in hourly systolic BP during the first 24 h were modeled using multivariable generalized estimating equations with an exchangeable correlation structure, clustering by patient, and inclusion of a group-by-time interaction term. Results: A total of 274 patients (mean age 71. 1 +/- 12. 2 years; 38. 7% female; median onset-to-arrival time, 2. 5 h IQR 1. 2–5. 3) were included. Among those, 53 patients (19. 3%) demonstrated IMP on immediate post-EVT perfusion MRI. Patients with IMP were more likely to have post-EVT eTICI 2b than those without IMP (75. 5% vs. 49. 8%, p<0. 01). The group-by-time interaction was significant (Wald F (23, 5765) =1. 55; P=. 046), indicating that post-EVT BP trajectories over the first 24 h differed by IMP status. Hour-specific contrasts showed significantly higher SBP in the IMP+ group at hours 4, 8–11, and 14 (Holm-adjusted P<0. 05). Conclusion: In this study, early SBP trajectories differed according to IMP, suggesting that post-EVT perfusion status may influence systemic hemodynamic responses. Immediate post-EVT perfusion MRI allowed early identification of IMP and its association with BP dynamics. These findings suggest the need for prospective studies to determine whether IMP-informed BP management improves outcomes.