Abstract T P13: Effect of Pre-treatment Cerebral Blood Volume and Time to Recanalization on Good Clinical Outcomes in Endovascular Thrombectomy

Introduction: Previous studies suggested that faster times to recanalization led to better clinical outcomes in patients after endovascular thrombectomy. Hypothesis: We assessed the hypothesis that an association between time to recanalization and clinical outcomes depends on cerebral blood volume (CBV) obtained from pre-treatment CT perfusion (CTP). Methods: In consecutive patients with acute ischemic stroke who were obtained successful recanalization (TICI 2A-3) by endovascular thrombectomy for internal carotid artery or middle cerebral artery M1 occlusion, we retrospectively analyzed the influence on clinical outcome of time to recanalization and relative CBV value (rCBV) evaluated by pre-treatment CTP. The patient population was divided into 3 groups according to rCBV: severe decreased rCBV group (rCBV 0.9). In each group, we compared time to recanalization from onset and CTP between good clinical outcome group (modified Rankin Scale score ≤2 at day 90) and poor clinical outcome group (modified Rankin Scale score ≥3). Results: Fifty-seven patients were eligible for this study. The mean age was 75.3 years and median baseline NIHSS was 17. Nineteen patients (33.3 %) achieved good clinical outcome. In the severe decreased rCBV group, mean time to recanalization from onset and CTP were 192 and 115 minutes, respectively, but no patient had a good clinical outcome. In the mild decreased rCBV group, mean time to recanalization from onset (180 versus 311 minutes, p=0.034) and CTP (102 versus 169 minutes, p=0.007) were significantly shorter in the good clinical outcome group. In the normal rCBV group, no association was found between clinical outcome and time to recanalization from onset (311 versus 313 minutes) and CTP (177 versus 184 minutes). Conclusions: Early successful recanalization resulted in better clinical outcome in patients with mild decreased rCBV. Severe decreased rCBV did not provide good outcome regardless of early successful recanalization.