Optimization of heart allocation: The transplant risk score

Am J Transplant. 2019 May;19(5):1507-1517. doi: 10.1111/ajt.15201. Epub 2019 Jan 7.

Abstract

The new French heart allocation system is designed to minimize waitlist mortality and extend the donor pool without a detrimental effect on posttransplant survival. This study was designed to construct a 1-year posttransplant graft-loss risk score incorporating recipient and donor characteristics. The study included all adult first single-organ recipients transplanted between 2010 and 2014 (N = 1776). This population was randomly divided in a 2:1 ratio into derivation and validation cohorts. The association of variables with 1-year graft loss was determined with a mixed Cox model with center as random effect. The predictors were used to generate a transplant-risk score (TRS). Donor-recipient matching was assessed using 2 separate recipient- and donor-risk scores. Factors associated with 1-year graft loss were recipient age >50 years, valvular cardiomyopathy and congenital heart disease, previous cardiac surgery, diabetes, mechanical ventilation, glomerular filtration rate and bilirubin, donor age >55 years, and donor sex: female. The C-index of the final model was 0.70. Correlation between observed and predicted graft loss rate was excellent for the overall cohort (r = 0.90). Hearts from high-risk donors transplanted to low-risk recipients had similar survival as those from low-risk donors. The TRS provides an accurate prediction of 1-year graft-loss risk and allows optimal donor-recipient matching.

Keywords: clinical research/practice; graft survival; health services and outcomes research; heart transplantation/cardiology; organ allocation; organ procurement and allocation; risk assessment/risk stratification.

MeSH terms

  • Adult
  • Aged
  • Algorithms
  • Female
  • France
  • Graft Survival
  • Heart Failure / diagnosis*
  • Heart Failure / surgery*
  • Heart Transplantation*
  • Humans
  • Male
  • Middle Aged
  • Multivariate Analysis
  • Postoperative Period
  • Proportional Hazards Models
  • Reproducibility of Results
  • Risk Assessment / methods*
  • Risk Factors
  • Tissue Donors
  • Tissue and Organ Procurement / standards*
  • Waiting Lists