title: Urgent listing exceptions and outcomes in pediatric heart transplantation: Comparison to standard criteria patients.
abstract: BACKGROUND
  United Network for Organ Sharing (UNOS) policy enables listing exceptions to avoid penalizing patients with waitlist mortality not captured by standard criteria. Outcomes among patients listed by exception have not been analyzed.
  
  
  METHODS
  We performed a retrospective analysis of pediatric (≤17 years of age, n = 4,706) listings (2006 to 2015) for primary, isolated heart transplantation within the UNOS data set, assessing Status 1A exception (n = 211, 4.5%) use across regions and patient characteristics and evaluating waitlist outcomes compared with candidates listed using standard criteria.
  
  
  RESULTS
  Death or removal for reason other than transplant did not differ between exception and standard criteria patients at 1 month (11.7% vs 16.2%, p = not statistically significant [NS]), 2 months (18.2% vs 29.0%, p = 0.11) or overall (16.1% vs 22.0%, p = NS) on the waitlist. Rates were higher than among Status 1B patients (1 month: 2.8%; 2 months: 5.6%; overall: 14.9%; p < 0.0001). The cumulative incidence of competing risks (transplantation, death/removal for reasons other than transplant and removal) did not differ when comparing Status 1A exception patients with Status 1A standard criteria patients. Use of 1A exceptions varied across UNOS regions (1.9% to 22.3%, p < 0.0001). Risk-adjusted modeling identified patients more (hypertrophic cardiomyopathy: odds ratio [OR] = 2.8, 95% confidence interval [CI] 1.5 to 5.0; restrictive cardiomyopathy: OR = 2.7, 95% CI 1.7 to 4.3) and less (low socioeconomic status: OR = 0.7, 95% CI 0.5 to 1.0) likely to use an exception. Use of exceptions was uncorrelated with regional outcomes.
  
  
  CONCLUSIONS
  Waitlist mortality among Status 1A exception patients is similar to that among those listed by standard criteria. However, variation in exception use across geography and demography may contribute to inequities in access to transplantation, particularly for those with low socioeconomic status. Standardization of practices may decrease regional variation and minimize inequities.
authors.affiliation: Nemours Cardiac Center, Nemours/A.I. duPont Hospital for Children, Wilmington, Delaware, USA; Departments of Surgery and Pediatrics, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, USA. Electronic address: rdavies@nemours.org.
authors.forename: Ryan R
authors.initials: RR
authors.lastname: Davies
authors.affiliation: Nemours Cardiac Center, Nemours/A.I. duPont Hospital for Children, Wilmington, Delaware, USA; Departments of Surgery and Pediatrics, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
authors.forename: Michael A
authors.initials: MA
authors.lastname: McCulloch
authors.affiliation: Rady Children's Hospital, San Diego, California, USA.
authors.forename: Shylah
authors.initials: S
authors.lastname: Haldeman
authors.affiliation: Nemours Cardiac Center, Nemours/A.I. duPont Hospital for Children, Wilmington, Delaware, USA; Departments of Surgery and Pediatrics, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
authors.forename: Samuel S
authors.initials: SS
authors.lastname: Gidding
authors.affiliation: Nemours Cardiac Center, Nemours/A.I. duPont Hospital for Children, Wilmington, Delaware, USA; Departments of Surgery and Pediatrics, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
authors.forename: Christian
authors.initials: C
authors.lastname: Pizarro
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D054625:Healthcare Disparities; D006333:Heart Failure / Q000401:mortality / Q000601:surgery*; D016027:Heart Transplantation / Q000592:standards* / Q000639:trends; D006801:Humans; D007223:Infant; D053208:Kaplan-Meier Estimate; D008297:Male; D020380:Needs Assessment; D018579:Patient Selection; D010372:Pediatrics; D016016:Proportional Hazards Models; D012042:Registries; D012189:Retrospective Studies; D018570:Risk Assessment; D016019:Survival Analysis; D061665:Time-to-Treatment; D009927:Tissue and Organ Procurement / Q000592:standards* / Q000639:trends; D014481:United States; D014850:Waiting Lists
keywords: allocation; cardiac transplantation; listing status; outcomes; pediatrics; survival analysis