Researchers at the Hospital for Sick Children, Toronto, Canada identified 135 patients with congenital heart disease diagnosed with arterial ischemic stroke during 1992-2008 and registered in the Canadian Pediatric Stroke Registry-Toronto site. Of the total cohort with sentinel stroke, 19 (14%) had a recurrence. Of 78 (58%) with neonatal sentinel stroke, 7 (9%) had a stroke recurrence. Ten years following a sentinel stroke, 27% had suffered a stroke recurrence, 26% had died, and 47% were alive without recurrence. Age at sentinel stroke was 0.5 yr (range 0.1-17.0). Stroke recurrence risk was highest immediately following the sentinel stroke and decreased over time. At time of recurrence, 50% were receiving anticoagulation. Recurrence risk factors included a mechanical valve, prothrombotic condition, and an acute infection at time of sentinel stroke. Hazard of mortality after recurrence was similar to mortality after sentinel stroke. More aggressive secondary prophylaxis in the early poststroke period may be indicated in patients at increased risk. 
COMMENT The Toronto team has demonstrated the relative safety of anticoagulant therapy in 123 children with arterial ischemic stroke, with a 4% risk of intracranial hemorrhage.