Outcomes of Mechanical Thrombectomy for Patients With Stroke Presenting With Low Alberta Stroke Program Early Computed Tomography Score in the Early and Extended Window

Key Points Question What is the 90-day outcome for patients with stroke presenting with an Alberta Stroke Program Early Computed Tomography Score (ASPECTS) of 2 to 5 who underwent mechanical thrombectomy? Findings In this multicenter cohort study of 2345 patients presenting with an intracranial internal carotid artery or M1 occlusion who underwent mechanical thrombectomy, 213 [9.1%] had an ASPECTS of 2 to 5, and 22% of these patients achieved favorable 90-day outcomes (modified Rankin scale score of 0-2). Patients who achieved successful recanalization were nearly 5 times more likely to achieve favorable outcomes compared with patients who had unsuccessful recanalization. Meaning This study suggests that patients with a low ASPECTS on presentation may achieve 90-day functional independence after mechanical thrombectomy if they achieve successful recanalization.
Importance Limited data are available about the outcomes of mechanical thrombectomy (MT) for real-world patients with stroke presenting with a large core infarct. Objective To investigate the safety and effectiveness of MT for patients with large vessel occlusion and an Alberta Stroke Program Early Computed Tomography Score (ASPECTS) of 2 to 5. Design, Setting, and Participants This retrospective cohort study used data from the Stroke Thrombectomy and Aneurysm Registry (STAR), which combines the prospectively maintained databases of 28 thrombectomy-capable stroke centers in the US, Europe, and Asia. The study included 2345 patients presenting with an occlusion in the internal carotid artery or M1 segment of the middle cerebral artery from January 1, 2016, to December 31, 2020. Patients were followed up for 90 days after intervention. The ASPECTS is a 10-point scoring system based on the extent of early ischemic changes on the baseline noncontrasted computed tomography scan, with a score of 10 indicating normal and a score of 0 indicating ischemic changes in all of the regions included in the score. Exposure All patients underwent MT in one of the included centers. Main Outcomes and Measures A multivariable regression model was used to assess factors associated with a favorable 90-day outcome (modified Rankin Scale score of 0-2), including interaction terms between an ASPECTS of 2 to 5 and receiving MT in the extended window (6-24 hours from symptom onset). Results A total of 2345 patients who underwent MT were included (1175 women [50.1%]; median age, 72 years [IQR, 60-80 years]; 2132 patients [90.9%] had an ASPECTS of ≥6, and 213 patients [9.1%] had an ASPECTS of 2-5). At 90 days, 47 of the 213 patients (22.1%) with an ASPECTS of 2 to 5 had a modified Rankin Scale score of 0 to 2 (25.6% [45 of 176] of patients who underwent successful recanalization [modified Thrombolysis in Cerebral Ischemia score ≥2B] vs 5.4% [2 of 37] of patients who underwent unsuccessful recanalization; P = .007). Having a low ASPECTS (odds ratio, 0.60; 95% CI, 0.38-0.85; P = .002) and presenting in the extended window (odds ratio, 0.69; 95% CI, 0.55-0.88; P = .001) were associated with worse 90-day outcome after controlling for potential confounders, without significant interaction between these 2 factors (P = .64). Conclusions and Relevance In this cohort study, more than 1 in 5 patients presenting with an ASPECTS of 2 to 5 achieved 90-day functional independence after MT. A favorable outcome was nearly 5 times more likely for patients with low ASPECTS who had successful recanalization. The association of a low ASPECTS with 90-day outcomes did not differ for patients presenting in the early vs extended MT window.
This cohort study uses data from the Stroke Thrombectomy and Aneurysm Registry to investigate the safety and effectiveness of mechanical thrombectomy for patients with large vessel occlusion and an Alberta Stroke Program Early Computed Tomography Score of 2 to 5.