Effects of Pretreatment Cerebral Blood Volume and Time to Recanalization on Clinical Outcomes in Endovascular Thrombectomy for Acute Ischemic Stroke

Background: Faster time to recanalization leads to better clinical outcomes in patients treated with endovascular thrombectomy. Whether the association between time to recanalization and clinical outcomes depends on cerebral blood volume (CBV) obtained from pretreatment computed tomography (CT) perfusion (CTP) imaging was investigated. Methods: In consecutive patients with acute ischemic stroke who achieved recanalization by endovascular thrombectomy for intracranial internal carotid artery or M1 occlusion, the effects on clinical outcome of time to recanalization and the relative CBV value (rCBV) assessed by pretreatment CTP were evaluated. The patient population was divided into 2 groups according to rCBV: normal rCBV group (rCBV >= .9) and low rCBV group (rCBV < .9). In each group, time to recanalization was compared between the good and the poor clinical outcome groups. Results: Sixty-four patients were eligible for this study. Twenty-six patients (40.6%) achieved good clinical outcomes. In the normal rCBV group, no association was found between clinical outcome and time to recanalization. In the low rCBV group, time to recanalization from CTP (101 minutes versus 136 minutes, P = .040) was significantly shorter in the good clinical outcome group. On binary logistic regression modeling, CTP to recanalization time (odds ratio 1.035 [1.004-1.067], P = .025) was an independent predictor of good clinical outcome only in the low rCBV group. Conclusions: The association between time to recanalization and clinical outcomes depends on rCBV obtained from pretreatment CTP. Time to recanalization is more important for good clinical outcomes in patients with low rCBV than in patients with normal rCBV.