Association of Clinical, Imaging, and Thrombus Characteristics With Recanalization of Visible Intracranial Occlusion in Patients With Acute Ischemic Stroke

Abstract

<div class="section"> <a class="named-anchor" id="ab-joi180093-1"> <!-- named anchor --> </a> <h5 class="section-title" id="d7701353e727">Question</h5> <p id="d7701353e729">What clinical, imaging, and thrombus characteristics are associated with recanalization of visible intracranial thrombus in patients with acute ischemic stroke receiving vs not receiving intravenous alteplase? </p> </div><div class="section"> <a class="named-anchor" id="ab-joi180093-2"> <!-- named anchor --> </a> <h5 class="section-title" id="d7701353e732">Findings</h5> <p id="d7701353e734">In this prospective cohort study of 575 patients with acute ischemic stroke and visible intracranial thrombus on computed tomographic angiography, thrombus recanalization occurred in 30.4% of patients within 6 hours of intravenous alteplase administration, and in 13.3% of patients who did not receive alteplase. More distal thrombus location, greater thrombus permeability, and longer time to recanalization assessment were associated with successful recanalization with intravenous alteplase. </p> </div><div class="section"> <a class="named-anchor" id="ab-joi180093-3"> <!-- named anchor --> </a> <h5 class="section-title" id="d7701353e737">Meaning</h5> <p id="d7701353e739">Among patients with acute ischemic stroke, clinical and imaging biomarkers were associated with intracranial thrombus recanalization. </p> </div><div class="section"> <a class="named-anchor" id="ab-joi180093-4"> <!-- named anchor --> </a> <h5 class="section-title" id="d7701353e743">Importance</h5> <p id="d7701353e745">Recanalization of intracranial thrombus is associated with improved clinical outcome in patients with acute ischemic stroke. The association of intravenous alteplase treatment and thrombus characteristics with recanalization over time is important for stroke triage and future trial design. </p> </div><div class="section"> <a class="named-anchor" id="ab-joi180093-5"> <!-- named anchor --> </a> <h5 class="section-title" id="d7701353e748">Objective</h5> <p id="d7701353e750">To examine recanalization over time across a range of intracranial thrombus occlusion sites and clinical and imaging characteristics in patients with ischemic stroke treated with intravenous alteplase or not treated with alteplase. </p> </div><div class="section"> <a class="named-anchor" id="ab-joi180093-6"> <!-- named anchor --> </a> <h5 class="section-title" id="d7701353e753">Design, Setting, and Participants</h5> <p id="d7701353e755">Multicenter prospective cohort study of 575 patients from 12 centers (in Canada, Spain, South Korea, the Czech Republic, and Turkey) with acute ischemic stroke and intracranial arterial occlusion demonstrated on computed tomographic angiography (CTA). </p> </div><div class="section"> <a class="named-anchor" id="ab-joi180093-7"> <!-- named anchor --> </a> <h5 class="section-title" id="d7701353e758">Exposures</h5> <p id="d7701353e760">Demographics, clinical characteristics, time from alteplase to recanalization, and intracranial thrombus characteristics (location and permeability) defined on CTA. </p> </div><div class="section"> <a class="named-anchor" id="ab-joi180093-8"> <!-- named anchor --> </a> <h5 class="section-title" id="d7701353e763">Main Outcomes and Measures</h5> <p id="d7701353e765">Recanalization on repeat CTA or on first angiographic acquisition of affected intracranial circulation obtained within 6 hours of baseline CTA, defined using the revised arterial occlusion scale (rAOL) (scores from 0 [primary occlusive lesion remains the same] to 3 [complete revascularization of primary occlusion]). </p> </div><div class="section"> <a class="named-anchor" id="ab-joi180093-9"> <!-- named anchor --> </a> <h5 class="section-title" id="d7701353e768">Results</h5> <p id="d7701353e770">Among 575 patients (median age, 72 years [IQR, 63-80]; 51.5% men; median time from patient last known well to baseline CTA of 114 minutes [IQR, 74-180]), 275 patients (47.8%) received intravenous alteplase only, 195 (33.9%) received intravenous alteplase plus endovascular thrombectomy, 48 (8.3%) received endovascular thrombectomy alone, and 57 (9.9%) received conservative treatment. Median time from baseline CTA to recanalization assessment was 158 minutes (IQR, 79-268); median time from intravenous alteplase start to recanalization assessment was 132.5 minutes (IQR, 62-238). Successful recanalization occurred at an unadjusted rate of 27.3% (157/575) overall, including in 30.4% (143/470) of patients who received intravenous alteplase and 13.3% (14/105) who did not (difference, 17.1% [95% CI, 10.2%-25.8%]). Among patients receiving alteplase, the following factors were associated with recanalization: time from treatment start to recanalization assessment (OR, 1.28 for every 30-minute increase in time [95% CI, 1.18-1.38]), more distal thrombus location, eg, distal M1 middle cerebral artery (39/84 [46.4%]) vs internal carotid artery (10/92 [10.9%]) (OR, 5.61 [95% CI, 2.38-13.26]), and higher residual flow (thrombus permeability) grade, eg, hairline streak (30/45 [66.7%]) vs none (91/377 [24.1%]) (OR, 7.03 [95% CI, 3.32-14.87]). </p> </div><div class="section"> <a class="named-anchor" id="ab-joi180093-10"> <!-- named anchor --> </a> <h5 class="section-title" id="d7701353e773">Conclusions and Relevance</h5> <p id="d7701353e775">In patients with acute ischemic stroke, more distal thrombus location, greater thrombus permeability, and longer time to recanalization assessment were associated with recanalization of arterial occlusion after administration of intravenous alteplase; among patients who did not receive alteplase, rates of arterial recanalization were low. These findings may help inform treatment and triage decisions in patients with acute ischemic stroke. </p> </div><p class="first" id="d7701353e778">This cohort study examines baseline clinical and biochemical variables, intracranial thrombus characteristics, and stroke workflow interval times associated with clot recanalization among patients with ischemic stroke treated with intravenous alteplase. </p>