Practice Changes at U.S. Transplant Centers After the New Adult Heart Allocation Policy

In October 2018, the U.S. heart allocation system expanded the number of priority "status" tiers from 3 to 6 and added cardiogenic shock requirements for some heart transplant candidates listed with specific types of treatments.

This study sought to determine the impact of the new policy on the treatment practices of transplant centers.

Initial listing data on all adult heart candidates listed from December 1, 2017 to April 30, 2019 were collected from the Scientific Registry of Transplant Recipients. The status-qualifying treatments (or exception requests) and hemodynamic values at listing of a post-policy cohort (December 2018 to April 2019) were compared with a seasonally matched pre-policy cohort (December 2017 to April 2018). Candidates in the pre-policy cohort were reclassified into the new priority system statuses by using treatment, diagnosis, and hemodynamics.

Comparing the post-policy cohort (N = 1,567) with the pre-policy cohort (N = 1,606), there were significant increases in listings with extracorporeal membrane oxygenation (+1.2%), intra-aortic balloon pumps (+ 4 %), and exceptions (+ 12%). Listings with low-dose inotropes (-18%) and high-dose inotropes (-3%) significantly decreased. The new priority status distribution had more status 2 (+14%) candidates than expected and fewer status 3 (-5%), status 4 (- 4%) and status 6 (-8%) candidates than expected (p values <0.01 for all comparisons).

After implementation of the new heart allocation policy, transplant centers listed more candidates with extracorporeal membrane oxygenation, intra-aortic balloon pumps, and exception requests and fewer candidates with inotrope therapy than expected, thus leading to significantly more high-priority status listings than anticipated. If these early trends persist, the new allocation system may not function as intended.