Impact of the new UNOS donor heart allocation system on waitlist outcomes and early post-transplant mortality among adults with congenital heart disease.

Adults with congenital heart disease (ACHD) experience worse waitlist outcomes and higher early post-transplant mortality compared to non-ACHD patients. On October 18, 2018; the UNOS donor heart allocation system was redesigned giving unique listing status to ACHD patients. The impact of this change on outcomes in transplant-listed patients is unstudied. Using the Scientific Registry of Transplant Recipients (SRTR) we compared ACHD patients listed for the first-time for heart transplantation from 2 eras of equal duration. We analyzed waitlist outcomes, post-transplant mortality and length of stay among ACHD patients in both eras and between ACHD and non-ACHD patients in the new era. Of 12723 listed patients, 535 had ACHD (293 in the new era) and 12188 did not (6258 in the new era). A total of 163 (56%) ACHD patients in the new era versus 150 (62%) in the prior era were transplanted; 11 (3.8%) versus 15 (6.2%) died on the waitlist; 32 (11%) versus 35 (14%) were delisted and 15 (9.2%) versus 19 (12.7%) died within 30 days of transplant respectively. The new UNOS donor heart allocation system improved waitlist outcomes among ACHD patients without altering early post-transplant outcomes or significantly changing the gap in outcomes compared to non-ACHD patients.