Patients with low stroke score may reach functional independence

Patients who present with a low Alberta Stroke Program Early Computed Tomography Score may achieve functional independence following mechanical thrombectomy, according to results of a retrospective cohort study.

Those with a low score who had successful recanalization had a significantly higher likelihood for a favorable outcome.

“The Alberta Stroke Program Early Computed Tomography Score (ASPECTS) is a 10-point scoring system based on the extent of early ischemic changes detected on the baseline non-contrasted computed tomography scan, with a score of 10 indicating normal and 0 indicating ischemic changes in all of the regions included in the score,” Eyad Almallouhi, MD, of the department of neurosurgery at the Medical University of South Carolina, and colleagues wrote in JAMA Network Open. “Patients with an ASPECTS lower than 6 were excluded from most clinical trials; therefore, data about their outcomes remain scarce, and whether these patients could still achieve benefits from [mechanical thrombectomy] remains unknown.”

Investigators aimed to examine the safety and effectiveness of mechanical thrombectomy among patients with large vessel occlusion who had an ASPECTS of between 2 and 5. They analyzed data of 2,345 patients (50.1% were women; median age, 72 years; 90.9% ASPECTS of 6; 9.1% ASPECTS of 2 to 5) included in the Stroke Thrombectomy and Aneurysm Registry, which combines prospectively maintained databases from 28 thrombectomy-capable stroke centers in the U.S., Europe and Asia. Included patients had occlusion in the internal carotid artery or M1 segment of the middle cerebral artery between January 2016 and December 2020. Follow-up occurred for 90 days after intervention. Patients received mechanical thrombectomy at one of the included centers. Almallouhi and colleagues used a multivariable regression model to examine factors linked to a favorable 90-day outcome, defined as a modified Rankin Scale score of between 0 and 2. Factors included interaction terms between an ASPECTS of 2 and 5 and receipt of mechanical thrombectomy in the extended window, or 6 to 24 hours from symptom onset.

Results showed 22.1% (n = 47) of the 213 patients with ASPECTS of between 2 and 5 at 90 days had a modified Rankin Scale score of between 0 and 2 (25.6% of patients who received successful recanalization compared with 5.4% of patients who received unsuccessful recanalization). Patients with a low ASPECTS (OR = 0.6; 95% CI, 0.38-0.85) and those who presented in the extended window (OR = 0.69; 95% CI, 0.55-0.88) had increased risk for worse 90-day outcome after controlling for potential confounders, with researchers noting no significant interaction between these two factors.

“Post-[mechanical thrombectomy] care represents another factor that modifies the outcomes of [mechanical thrombectomy] in general,” Almallouhi and colleagues wrote. “This care includes blood pressure control, decompressive hemicraniectomy protocols and the use of antiplatelets. Future studies are needed to evaluate the association of these factors with [mechanical thrombectomy] for patients with a low ASPECTS.”