Abstract 16610: Waitlist Characteristics and Outcomes Following the 2016 Revision of US Pediatric Heart Allocation Policy

Abstract

Background: US pediatric heart allocation was revised in March 2016 to more appropriately categorize candidates with the most urgent need for heart transplantation (HT), including children with congenital heart disease (CHD) listed status 1A on inotropic support. We sought to assess the impact of these revisions on waitlist (WL) characteristics and mortality. Methods: Children (<18 yo) listed for heart transplantation (HT) in the UNOS database between 12/16/11 and 11/7/17 were stratified based on whether they were listed before (PRE) or after (POST) criteria revision. Comparisons were made using Chi-Square or Wilcoxon rank sum tests and WL mortality was compared by competing outcomes analyses. Results: After criteria revision: 1) the proportions of status 1A candidates decreased at listing (69 vs. 53%, p<0.001) and HT (89 vs. 82%, p<0.001); 2) patients with CHD comprised a greater proportion of 1A candidates at listing (47 vs. 64%, p<0.001) and at HT (42 vs. 51%; p<0.008); 3) the use of status 1A exceptions among CM patients increased (5 vs. 24%, p<0.001); and overall WL mortality and WL mortality for those listed status 1A were unchanged (fig 1a-b). When stratified by diagnosis, overall CHD WL mortality improved with no difference in CM WL mortality following criteria revision, and CHD WL mortality remains nearly twice that of CM candidates (fig 1c-d). However, when comparing CHD and CM candidates listed 1A without exception, CHD WL mortality was unchanged while CM WL mortality increased (fig 1e-f). Conclusions: As intended, there are fewer status 1A listings and enrichment of CHD patients in the status 1A group following criteria revision. Though overall WL mortality for CHD candidates improved, it remains nearly twice that of CM. Also, the lack of improvement in WL mortality for status 1A CHD candidates may be due to the marked increase in status 1A exemptions for CM candidates. Additional policy changes may further narrow the disparity in WL survival between CHD and CM.