Abstract Number ‐ 22: Hemorrhagic Outcomes in Patients Demonstrating Early Venous Filling After Mechanical Thrombectomy For Acute Ischemic Stroke

Introduction Endovascular thrombectomy (EVT) for acute ischemic infarcts with large vessel occlusion have been shown to improve functional outcomes. However, there is still the risk of hemorrhagic transformation (HT). Early identification of patients at risk of HT is paramount to enhance EVT outcomes. EVF can be an indicator of the hyperemia that occurs following an infarct. We evaluated if early venous filling (EVF) defined as contrast filling of any cerebral vein within the arterial phase on angiogram can predict individuals at a higher risk of HT after EVT. Methods From the SELECT cohort,EVT patients with evaluable digital subtraction angiography were included in the study. Baseline clinical and imaging characteristics as well as clinical and hemorrhagic outcomes were compared between patients demonstrating EVF and no EVF. Association between EVF with symptomatic ICH and parenchymal hemorrhage was examined using multivariable logistic regression models. Results 46/254 (18%) patients had EVF at the end of the procedure. Age and NIHSS were similar between the patients with and without EVF, although patients with EVF presented earlier (1.39 (0.88‐2.75) hours vs 2.62 (1.10‐4.28) hours, p = 0.024), and demonstrated lower CT ASPECTS (7 (6‐9) vs 8 (7‐9), p = 0.022). The presence of EVF was associated with significantly higher odds of sICH (EVF: 8.7% vs no EVF: 5.6%, aOR: 4.72, 95% CI: 1.05‐21.28, p = 0.043) and demonstrated a trend towards higher odds of parenchymal hemorrhage type 1 or 2 (EVF: 10.9% vs no EVF: 6.3%, aOR: 3.64, 95% CI: 0.96‐13.73, p = 0.057) and mortality (EVF: 17% vs no EVF: 12%, aOR: 3.22, 95% CI: 0.93‐11.13, p = 0.064). Functional outcomes did not differ at 90 days between the two groups Conclusions Early identification of EVF may help to identify patients with increased risk of hemorrhagic transformation after EVT. This finding was independent from time last known well. While EVF is suggestive of hyperemia it is also a biomarker of infarct volume and may help to implement early therapeutic measurements to reduce hemorrhagic transformation risk such as strict blood pressure control. Further studies to evaluate EVF as a potential marker for hemorrhagic transformation are required.