Outcome, incidence and risk factors for stroke after pediatric heart transplantation: An analysis of the International Society for Heart and Lung Transplantation Registry

Background In the registry of the International Society for Heart and Lung Transplantation (ISHLT), cerebrovascular accidents are the fifth most common cause for mortality after pediatric heart transplantation (PHTx), but details are lacking in the literature. The purpose of this analysis of the ISHLT registry was to determine the prevalence, risk factors and outcomes of stroke after PHTx. Methods Data from the ISHLT registry (1998 to 2010) were used to identify all patients whose primary transplantation was performed at <18 years of age. Of the 10,441 transplants reviewed, 9,837 primary transplants and 604 retransplants were analyzed. Results Three hundred thirty-three (3%) patients had a stroke after PHTx; 54% were male, median age at PHTx was 6 years (0 to 17 years), and 44% had a diagnosis of congenital heart disease (CHD). Freedom from stroke was 99% at 1 month, 97% at 5 years, 95% at 10 years and 91% at 20 years post-PHTx. After a stroke, survival at 1 month, 1 year and 5 years was 83%, 69% and 55%, respectively. Multivariable independent risk factors for stroke included a primary diagnosis of congenital heart disease [hazard ratio (HR) 1.4 (1.1 to 1.7), p = 0.01], previous stroke [HR 4.5 (3.2 to 6.2), p < 0.001], history of aborted sudden death [HR 1.5 (1.1 to 2), p = 0.01], ventricular assist device [HR 1.5 (1.1 to 2.2), p = 0.03] or extracorporeal membrane oxygenation [HR 1.7 (1.2 to 2.2), p = 0.01], post-operative dialysis [HR 3.3 (2.3 to 4.7), p < 0.001], infection requiring antibiotics before discharge [HR 1.9 (1.4 to 2.5), p < 0.001], pacemaker implantation [HR 1.6 (1 to 2.5), p = 0.04] or drug-treated hypertension [HR 1.4 (1.1 to 1.8), p = 0.003] during follow-up. Conclusions Stroke after pediatric heart transplantation is associated with increased mortality. Congenital heart disease and mechanical support both portend greater risk, in addition to markers of increased pre- and post-transplant medical acuity.