Mechanical Thrombectomy for Acute Stroke: Early versus Late Time Window Outcomes

Abstract

BACKGROUND AND PURPOSE: Recent trials have shown benefit of thrombectomy in patients selected by penumbral imaging in the late (>6 hours) window. However, the role penumbral imaging is not clear in the early (0-6 hours) window. We sought to evaluate if time to treatment modifies the effect of endovascular reperfusion in stroke patients with evidence of salvageable tissue on CT perfusion (CTP). METHODS: We retrospectively analyzed consecutive patients who underwent thrombectomy in a single center. Demographics, comorbidities, National Institute of Health Stroke Scale (NIHSS), rtPA administration, ASPECTS, core infarct volume, onset to skin puncture time, recanalization (mTICI IIb/III), final infarct volume were compared between patients with good and poor 90-day outcomes (mRS 0-2 vs. 3-6). Multivariable logistic regression analyses were used to identify independent predictors of a good (mRS 0-2) 90-day outcome. RESULTS: A total of 235 patients were studied, out of which 52.3% were female. Univariate analysis showed that the groups (early vs. late) were balanced for age (P =.23), NIHSS (P =.63), vessel occlusion location (P =.78), initial core infarct volume (P =.15), and recanalization (mTICI IIb/III) rates (P =.22). Favorable outcome (mRS 0-2) at 90 days (P =.30) were similar. There was a significant difference in final infarct volume (P =.04). Shift analysis did not reveal any significant difference in 90-day outcome (P =.14). After adjustment; age (P