Association Between Thrombectomy and Functional Outcomes in Pediatric Patients With Acute Ischemic Stroke From Large Vessel Occlusion.

Importance: Pediatric large vessel occlusion (LVO) stroke has a poor natural history. However, uptake of mechanical thrombectomy is hindered by a lack of clinical trial data in children. A randomized clinical trial is not feasible due to small sample sizes and absence of equipoise. Objective: To evaluate whether pediatric patients with acute LVO stroke who undergo thrombectomy have better clinical outcomes than matched patients managed conservatively. Design, Setting, and Participants: This matched case-control study used pooled stroke registry data from 5 tertiary referral hospitals in Australia and Canada from January 2011 to April 2022. Patients were aged 1 month to younger than 18 years with acute LVO stroke. Pooled data identified 31 thrombectomy patients and 46 control patients. Five patients undergoing thrombectomy with basilar artery occlusion were excluded due to insufficient controls. Using a hierarchal matching system (site of occlusion, age group, side of occlusion, and sex), deidentified consensus matching of patients and controls was undertaken while blinded to clinical outcome. Data were analyzed from July to November 2022. Exposure: In the case cohort, mechanical thrombectomy was undertaken for management of acute LVO stroke. The control cohort received medical treatment only. Main Outcomes and Measures: The primary outcome was the functional clinical status 3 months following stroke, measured by the pediatric modified Rankin Scale (mRS). Clinical outcomes were compared between groups using ordinal regression analysis. Results: Of 52 included patients, 31 (60%) were male, and the mean (SD) age was 10.3 (4.4) years. Matching was achieved for 26 children undergoing thrombectomy with 26 controls. There was no significant difference between groups for site or side of occlusion, age, sex, etiology, thrombolysis status, baseline Alberta Stroke Programme Early CT Score, or time since last seen well to presentation. Patients undergoing thrombectomy had superior clinical outcomes than control patients at 3 months on the pediatric mRS (odds ratio, 3.76; 95% CI, 1.32-10.67; P = .01). These superior outcomes were maintained at final follow-up (odds ratio, 3.65; 95% CI, 1.25-10.68; P = .02). Conclusions and Relevance: In the absence of a randomized clinical trial, this case-control study demonstrates better clinical outcomes with thrombectomy than medical management alone for pediatric patients aged 2 to 18 years with anterior circulation LVO stroke.