Abstract 15491: Have Heart Transplant Allocation Policy Changes Brought Improvements in Mortality for Children and Adults With Congenital Heart Disease? A UNOS Database Analysis

Abstract

Introduction: The United Network of Organ Sharing (UNOS) made changes to the priority for allocation of hearts for transplantation (HT) in 2016 for pediatric patients and 2018 for adult patients. There are limited data describing the association of these changes with waitlist outcomes in patients with congenital heart disease (CHD). Methods: The United Network for Organ Sharing (UNOS) database was queried for pediatric (<18 y/o, PCHD), and adult (18yo-50yo, ACHD), patients with a CHD diagnosis listed for HT. Cohorts were grouped into pre and post-allocation change eras: PCHD 1/1/11-3/21/15 and 1/1/17-12/31/21, ACHD 1/1/15-10/17/18 and 1/1/19 to 12/31/21. Differences in era for survival from the time of listing for HT were compared using competing risk models. Results: We identified 3,646 patients listed for HT during the study period including 1,520 PCHD and 432 ACHD pre-allocation change and 1,443 and 251 post. More PCHD patients in the post cohort were supported with ventricular assist devices (7.6% vs 3.2%) while fewer were on inotropes (41% vs 47%), intubated (18% vs 21%) or on ECMO (5.3% vs 7.9%) (p for all <0.01 ). For ACHD, ECMO (4.8% vs 1.9%) and intra-aortic balloon pump (6.8% vs 1.9%) use was more prevalent in the post era (p<0.05 for both). In a competing risk model adjusting for illness severity, the HR for death or waitlist removal within 1 year of HT listing was higher in the pre-allocation era compared to post for PCHD (HR 1.27 [95% CI 1.06-1.52]) but unchanged for ACHD (HR 1.36 [95% CI 0.77-2.41]). Figure 1 Conclusions: ACHD patients did not have the mortality benefit from policy changes which other groups, including PCHD, have experienced. Incorporating measures into the allocation system which more completely capture the illness severity that comes with ACHD are warranted, as are strategies to improve long term survival in this growing population.