Impact of the United Network for organ sharing 2018 donor heart allocation system on transplant morbidity and mortality

Clin Transplant. 2021 Feb;35(2):e14181. doi: 10.1111/ctr.14181. Epub 2021 Jan 15.

Abstract

Background: While the revised UNOS HTx donor allocation system aimed to minimize waitlist mortality by prioritizing more critically ill transplant candidates, there is concern for increased post-transplant morbidity and mortality. We examined the impact of the revised allocation system on waitlist and post-transplant outcomes at a high-volume transplant center.

Methods: One hundred and sixty nine adult patients underwent first-time single-organ HTx one year before (Era 1:79 patients) and after (Era 2:90 patients) implementation of the new allocation system (10/18/2018). Clinical characteristics, waitlist outcomes, and post-transplant morbidity and mortality were compared.

Results: Era 2 patients were twice as likely to be transplanted on temporary mechanical circulatory support (43% vs. 19%, p < .0001). While Era 2 waitlist time was shorter (10 vs. 43 days, p < .001), exception status requests (21.1% vs. 17.9%) and waitlist mortality (3.3% vs. 2.2%) were similar. There was no difference in primary graft dysfunction, intensive care unit or hospital length of stay, readmissions, rejection, allograft vasculopathy, or 1-year survival (91.1% vs. 93.7%).

Conclusions: In a high-volume center, the revised HTx allocation system shortened waitlist time with no significant change in waitlist mortality or observed impact on post-transplant outcomes. With careful patient selection, the revised allocation system may optimize waitlist and post-transplant outcomes.

Keywords: allocation system; heart transplant; mechanical circulatory support.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Heart Transplantation*
  • Humans
  • Morbidity
  • Tissue Donors
  • Tissue and Organ Procurement*
  • Waiting Lists