Menon BK, et al. - In patients with ischemic stroke treated with intravenous alteplase or not treated with alteplase, researchers tested recanalization over time across a range of intracranial thrombus occlusion sites and clinical and imaging characteristics in this multicenter prospective cohort study. Findings suggested an association of more distal thrombus location, greater thrombus permeability, and longer time to recanalization assessment with recanalization of arterial occlusion after administration of intravenous alteplase in patients with acute ischemic stroke. It was noted that rates of arterial recanalization were low among patients who did not receive alteplase. In patients with acute ischemic stroke, these findings might help inform treatment and triage decisions.

Methods

• Researchers enrolled study participants (n=575) from 12 centers (in Canada, Spain, South Korea, the Czech Republic, and Turkey) with acute ischemic stroke and intracranial arterial occlusion as demonstrated on computed tomographic angiography (CTA).
• Main exposures analyzed were demographics, clinical characteristics, time from alteplase to recanalization, and intracranial thrombus characteristics (location and permeability) defined on CTA.
• Main outcomes and measures analyzed were recanalization on repeat CTA or on first angiographic acquisition of affected intracranial circulation obtained within 6 hours of baseline CTA, characterized utilizing the revised arterial occlusion scale (scores from 0 [primary occlusive lesion remains the same] to 3 [complete revascularization of primary occlusion]).

Results

• Among 575 participants (51.5% of whom were men; median age, 72 years [interquartile range (IQR): 63-80]; median time from patient last known well to baseline CTA, 114 minutes [IQR: 74-180]), 275 (47.8%) received intravenous alteplase only, 195 (33.9%) received intravenous alteplase in combination with 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).
• Findings revealed that 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% confidence interval (CI): 10.2% to 25.8%]).
• The following factors were related to 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]) among patients receiving alteplase.