Hemorrhagic Transformation Following Childhood Cardioembolic Stroke Is Not Increased in Anticoagulated Patients

Objective: To characterize the risk of hemorrhagic transformation following cardioembolic stroke in childhood, and whether anticoagulation impacts that risk. Methods: Ninety-five children (1 month-18 years) with cardioembolic arterial ischemic stroke between January 1, 2009, and December 31, 2019, at 2 institutions were identified for retrospective chart review. Neuroimaging was reviewed to assess for hemorrhagic transformation. Results: There were 11 cases of hemorrhagic transformation; 8 occurred within 2 days of stroke diagnosis. Risk of hemorrhagic transformation did not differ in patients with and without anticoagulation use (15% vs 9%, estimated risk difference 5%; CI -9%, 19%). Stroke size did not predict hemorrhagic transformation (OR 1.004, 95% CI 0.997, 1.010). Risk of hemorrhagic transformation was higher in strokes that occurred in the inpatient compared with the outpatient setting (16% vs 6%). Conclusion: Hemorrhagic transformation occurred in 11% of pediatric cardioembolic ischemic stroke, usually within 2 days of stroke diagnosis, and was not associated with anticoagulation or stroke size.