Ultraearly assessed reperfusion status after middle cerebral artery recanalization predicting clinical outcome.

Abstract

Mechanical thrombectomy has high evidence in stroke therapy; however, successful recanalization guarantees not a favorable clinical outcome. We aimed to quantitatively assess the reperfusion status ultraearly after successful middle cerebral artery (MCA) recanalization to identify flow parameters that potentially allow predicting clinical outcome. Sixty-seven stroke patients with acute MCA occlusion, undergoing recanalization, were enrolled. Using parametric color coding, a post-processing algorithm, pre-, and post-interventional digital subtraction angiography series were evaluated concerning the following parameters: pre- and post-procedural cortical relative time to peak (rTTP) of MCA territory, reperfusion time, and index. Functional long-term outcome was assessed by the 90-day modified Rankin Scale score (mRS; favorable: 0-2). Cortical rTTP was significantly shorter before (3.33±1.36seconds; P=.03) and after intervention (2.05±0.70seconds; P=.003) in patients with favorable clinical outcome. Additionally, age (P=.005) and initial National Institutes of Health Stroke Scale score (P=.02) were significantly different between the patients, whereas reperfusion index and time as well as initially estimated infarct size were not. In multivariate analysis, only post-procedural rTTP (P=.005) was independently associated with favorable clinical outcome. 2.29seconds for post-procedural rTTP might be a threshold to predict favorable clinical outcome. Ultraearly quantitative assessment of reperfusion status after successful MCA recanalization reveals post-procedural cortical rTTP as possible independent prognostic value in predicting favorable clinical outcome, even determining a threshold value might be possible. In consequence, focusing stroke therapy on microcirculatory patency could be valuable to improve outcome.