BACKGROUND AND OBJECTIVES: Cardiac abnormalities are among the most common and complex risk factors of pediatric acute ischemic stroke (AIS). Although endovascular treatment (EVT) is increasingly used in children, uncertainty persists regarding its safety and effectiveness in patients with underlying cardiac disease, leading to therapeutic hesitation in this high-risk population. The aim of this study was to determine whether the association between EVT and functional outcomes after pediatric AIS differs according to cardiac abnormality status.

METHODS: This study was a retrospective secondary analysis of a prospective, multinational cohort registry (Save ChildS Pro). The registry enrolled patients between 2018 and 2023, with 90-day follow-up. Participants included children aged 28 days to 18 years with confirmed AIS due to large vessel occlusion and available 90-day Pediatric Stroke Outcome Measure (PSOM) scores. Cardiac abnormalities were defined as congenital or acquired cardiac disease documented by echocardiography or medical records. The primary outcome was poor functional outcome at 90 days, defined as PSOM score >0.5. Secondary outcomes included ordinal 90-day modified Rankin Scale (mRS) scores and longitudinal neurologic recovery assessed using the Pediatric NIH Stroke Scale (pedNIHSS). Treatment-subgroup interaction was assessed using penalized logistic regression.

RESULTS: Of 208 eligible patients, 178 were included in the final analysis after excluding those with missing outcome data [43% female; mean age: 11.5 years]. Among 178 children, 56 (31.5%) had cardiac abnormalities. EVT was more frequently performed in children with cardiac abnormalities than in those without (p = 0.003). Cardiac abnormality status was not independently associated with outcome (odds ratio, 0.93; 95% CI, 0.36-2.52), and no significant interaction between EVT and cardiac abnormality was observed. Ordinal mRS shift analysis and longitudinal pedNIHSS modeling supported similar recovery trajectories. Adverse event rates did not differ by EVT status in either subgroup.

DISCUSSION: In this multinational pediatric AIS cohort, EVT was associated with improved functional outcomes and accelerated neurologic recovery, with no evidence that cardiac abnormality status modifies association of treatment with outcome or safety. These findings support consideration of EVT in children with cardiac abnormalities when clinically indicated.

CLASSIFICATION OF EVIDENCE: This study provides class IV evidence that endovascular therapy in pediatric patients with AIS is associated with improved functional outcome irrespective of underlying cardiac abnormality status.