Abstract TP162: Patterns of Pre-Stroke Atherosclerotic Stenosis and Pretreatment Collateral Status in Acute Ischemic Stroke

Abstract

Background: To date, there is no consensus regarding the factors associated with collaterals in acute ischemic stroke. Our study attempts to examine variables associated with pretreatment collaterals. Methods: From our hospital stroke registry, we retrospectively recruited 115 patients with acute anterior circulation infarct considered for endovascular reperfusion therapy. Collateral score (0-3) was rated using pretreatment CT angiography. Score of 0 or 1 (≤50% filling of the occluded territory) was considered as poor collaterals. The patterns of steno-occlusion other than culprit occlusion for infarct were classified into intracranial or extracranial atherosclerotic stenosis based on the location of steno-occlusion (> 50% on CTA). Results: Forty five of the 115 patients had poor collaterals. Variables (with univariate P< 0.1) associated with collaterals were, as pretreatment variables, older age ( ≥65 years) (P=0.067), hypertension (P=0.034), diabetes (P=0.093), initial NIHSS (P=0.002), location of culprit occlusion for infarct (P=0.001), intracranial stenosis (P=0.003), and as treatment or post-treatment variables, use of intravenous tissue plasminogen activator (P=0.004), successful recanalization (TICI grade 2b or 3: P=0.009), symptomatic intracranial hemorrhage (P=0.004), final infarct size (P<0.001). When multivariable logistic regression for poor collaterals was performed using the pretreatment variables, internal carotid artery occlusion and intracranial stenosis were significantly associated with poor collaterals (Table). Conclusions: Coincidental intracranial atherosclerotic stenosis is associated with pretreatment poor collaterals during acute stage of stroke. It might be because collateral flow is assumed to be largely dependent on flow from non-occluded intracranial arteries neighboring to culprit vascular lesion for infarct.