title: Should orthotopic heart transplantation using marginal donors be limited to higher volume centers?
abstract: BACKGROUND
  This study examined whether institutional volume impacts outcomes after orthotopic heart transplantation (OHT) utilizing marginal donors.
  
  
  METHODS
  Adult patients undergoing OHT with the use of marginal donors between 2000 and 2010 were identified in the United Network for Organ Sharing database. A previously derived and validated donor risk score (range, 1 to 15) was used to define marginal donors as those in the 90th percentile of risk (score≥7). Patients were stratified into equal-size tertiles based on overall institutional OHT volume. Posttransplant outcomes were compared between these center cohorts.
  
  
  RESULTS
  A total of 3,176 OHTs utilizing marginal donors were identified. In Cox regression analysis, recipients undergoing OHT at low-volume centers were at significantly increased risk of 30-day (hazard ratio 1.82 [1.31 to 2.54], p<0.001), 1-year (hazard ratio 1.40 [1.14 to 1.73], p=0.002), and 5-year posttransplant mortality (hazard ratio 1.29 [1.10 to 1.52], p=0.02). These findings persisted after adjusting for recipient risk, differences in donor risk score, and year of transplantation (each p<0.05). In Kaplan-Meier analysis, there was a similar trend of decreasing 1-year survival with decreasing center volume: high (86.0%), intermediate (85.7%), and low (81.2%; log rank p=0.003). Drug-treated rejection within the first post-OHT year was more common in low-volume versus high-volume centers (34.3% versus 24.2%, p<0.001). At an overall mean follow-up of 3.4±2.9 years, low-volume centers also had higher incidences of death due to malignancy (2.8% versus 1.3%, p=0.01) or infection (6.2% versus 4.1%, p=0.02).
  
  
  CONCLUSIONS
  Consolidating the use of marginal donors to higher volume centers may be prudent in improving post-OHT outcomes in this higher risk patient subset.
authors.affiliation: Division of Cardiac Surgery, Department of Surgery, Johns Hopkins Hospital, Baltimore, Maryland 21287, USA.
authors.forename: Arman
authors.initials: A
authors.lastname: Kilic
authors.forename: Eric S
authors.initials: ES
authors.lastname: Weiss
authors.forename: Jeremiah G
authors.initials: JG
authors.lastname: Allen
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: George
authors.forename: David D
authors.initials: DD
authors.lastname: Yuh
authors.forename: Ashish S
authors.initials: AS
authors.lastname: Shah
authors.forename: John V
authors.initials: JV
authors.lastname: Conte
mesh_terms: D000046:Academic Medical Centers / Q000706:statistics & numerical data; D000328:Adult; D000704:Analysis of Variance; D002423:Cause of Death; D016208:Databases, Factual; D004502:Education, Medical, Continuing; D005260:Female; D006084:Graft Rejection; D006085:Graft Survival; D016027:Heart Transplantation / Q000379:methods / Q000401:mortality* / Q000706:statistics & numerical data*; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D018570:Risk Assessment; D015996:Survival Rate / Q000639:trends; D014019:Tissue Donors / Q000706:statistics & numerical data*; D009927:Tissue and Organ Procurement / Q000458:organization & administration*; D014184:Transplantation, Homologous / Q000379:methods / Q000401:mortality / Q000706:statistics & numerical data; D016896:Treatment Outcome; D016526:Workload