Serial Alberta Stroke Program early CT score from baseline to 24 hours in Solitaire Flow Restoration with the Intention for Thrombectomy study: a novel surrogate end point for revascularization in acute stroke.

Abstract

The Alberta Stroke Program Early CT Score (ASPECTS) on baseline imaging is an established predictor of acute ischemic stroke outcomes. We analyzed change on serial ASPECTS at baseline and 24-hour imaging in the Solitaire Flow Restoration with the Intention for Thrombectomy (SWIFT) study to determine prognostic value and to identify subgroups with extensive injury after intervention. ASPECTS at baseline and 24 hours was independently scored in all anterior circulation SWIFT cases, blinded to all other trial data. ASPECTS at baseline, at 24 hours, and serial changes were analyzed with univariate and multivariate approaches. One hundred thirty-nine patients (mean age, 67 [SD, 12] years; 52% women; median National Institutes of Health Stroke Scale, 18 [interquartile range, 8-28]) with complete data at both time points were studied. Multivariate analyses showed that higher 24-hour ASPECTS predicted good clinical outcome (day 90 modified Rankin Scale, 0-2; odds ratio, 1.67; P<0.001). Among patients with high baseline ASPECTS (8-10; n=109), dramatic infarct progression (decrease in ASPECTS ≥6 points at 24 hours) was noted in 31 of 109 (28%). Such serial ASPECTS change was predicted by higher baseline systolic blood pressure (P=0.019), higher baseline blood glucose (P=0.133), and failure to achieve Thrombolysis in Cerebral Infarction score of 2b/3 reperfusion (P<0.001), culminating in worse day 90 modified Rankin Scale outcomes (mean modified Rankin Scale, 4.4 versus 2.7; P<0.001). Twenty-four-hour ASPECTS provides better prognostic information compared with baseline ASPECTS. Predictors of dramatic infarct progression on ASPECTS are hyperglycemia, hypertension, and nonreperfusion. Serial ASPECTS change from baseline to 24 hours predicts clinical outcome, providing an early surrogate end point for thrombectomy trials. http://www.clinicaltrials.gov. Unique identifier: NCT01054560.