title: Risk stratification and transplant benefit in children listed for heart transplant in the United States.
abstract: BACKGROUND
  The sickest children among those listed for heart transplant (HT) are also at higher risk of post-transplant mortality. We hypothesized that transplant benefit, defined as percentage reduction in risk of 1-year mortality on receiving HT, increases with higher risk of wait-list mortality.
  
  
  RESULTS
  We analyzed all children aged <18 years listed for first HT in the United States between July 2004 and December 2010. We developed a model for 90-day wait-list mortality (or removal because of deterioration) and stratified listed children into deciles based on their risk of wait-list mortality. Listed children were followed up for 1 year to assess cumulative 1-year wait-list mortality among the 10 risk groups. We developed a model for 1-year post-transplant mortality to estimate the risk of post-transplant mortality for children in each risk group. Of 2979 listed children, 15% reached the wait-list end point within 90 days and 18% within 1 year. Of 2034 HT recipients, 6.8% died within 90 days and 10.8% within 1 year. The risk of 90-day wait-list mortality increased progressively from 2.4% to 51.6% from the first to the tenth risk decile. Transplant benefit increased progressively across the wait-list risk groups (P<0.001 for trend). However, transplant benefit for children in the top 5% of risk (7.4%) was lower than that for children in the 91st to 95th percentile of risk (10.3%).
  
  
  CONCLUSIONS
  Sicker children on the wait-list benefit more from HT unless the post-transplant mortality is predicted to be very high. Whether consideration of transplant benefit in allocation policy can improve overall survival among listed children requires further analysis.
authors.affiliation: Department of Cardiology, Boston Children's Hospital, Boston, MA 02115, USA. TP.Singh@cardio.chboston.org
authors.forename: Tajinder P
authors.initials: TP
authors.lastname: Singh
authors.forename: Christopher S
authors.initials: CS
authors.lastname: Almond
authors.forename: Gary
authors.initials: G
authors.lastname: Piercey
authors.forename: Kimberlee
authors.initials: K
authors.lastname: Gauvreau
mesh_terms: D009202:Cardiomyopathies / Q000401:mortality / Q000601:surgery*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006330:Heart Defects, Congenital / Q000401:mortality / Q000601:surgery*; D016027:Heart Transplantation / Q000401:mortality; D006801:Humans; D007223:Infant; D008297:Male; D015233:Models, Statistical; D015999:Multivariate Analysis; D018570:Risk Assessment; D012720:Severity of Illness Index; D016896:Treatment Outcome; D014481:United States; D014850:Waiting Lists / Q000401:mortality
keywords: heart failure; pediatrics; risk factors; survival; transplantation