Stroke recurrence in children with congenital heart disease

Objective: Pediatric arterial ischemic stroke (AIS) carries an important morbidity and mortality burden. Congenital heart disease (CHD) is among the most important risk factors for pediatric AIS. Data on stroke recurrence in childhood CHD are lacking, resulting in uncertainty regarding optimal strategies for preventing recurrence. Methods: In the Canadian Pediatric Ischemic Stroke Registry-Toronto site, we identified children (birth to 18 years) with CHD diagnosed with AIS during 1992-2008. Data were abstracted from both stroke and cardiac surgery databases. Time-dependent outcomes (death and recurrent stroke) following sentinel stroke were parametrically modeled in competing risk analysis. Factors predicting stroke recurrence in parametric survival models were sought in parametric survival model analyses using backward variable selection of variables. Results: A total of 135 patients (19 with recurrence, 116 without recurrence) were studied. In competing risk analysis, 10 years following sentinel stoke, 27% had experienced a stroke recurrence, 26% had died, and 47% were alive and free from recurrence. Stroke recurrence risk decreased over time from sentinel stroke. Approximately 50% of patients were receiving anticoagulation at recurrence. Significant factors associated with recurrence included the presence of a mechanical valve, prothrombotic condition, and an acute infection at the time of sentinel stroke. Hazard of mortality after recurrence was similar to mortality after sentinel stroke (hazard ratio, 1.3; p = 0.75). Interpretation: Stroke recurrence was relatively common in neonates and children with CHD. Identified groups of patients at increased risk may require more aggressive secondary prophylaxis, especially in the early poststroke period.