Impact of 2018 Donor Heart Allocation Policy Change on Patients on Biventricular Support: A UNOS Database Analysis

In the United States, the donor heart allocation policy change in October 2018 granted high priority to patients on temporary mechanical circulatory support (MCS), positively influencing their pre-transplant outcomes with reduced waitlist time. However, the impact of this policy change on patients requiring biventricular support remains undetermined.

We analyzed data from the United Network for Organ Sharing (UNOS) database from May 2013 to March 2024. Patients with biventricular assist devices (BiVADs), including temporary or durable devices, and total artificial hearts (TAHs) were included. The cohort was divided into two groups based on listing: before and after policy change groups. Waitlist and post-transplant survival were compared between both groups.

Patients on biventricular support comprised 1.5% (611/39 829) of all waitlisted candidates, and 2.6% (732/28 643) of all isolated heart transplants. There was a significantly lower prevalence of biventricular support after the policy change in both waitlisted candidates (Pre: 2.0% versus Post: 1.2%, p < 0.001) and at the time of transplantation (Pre: 3.1% versus Post: 2.1%, p < 0.001). Following the policy change, there was a significantly lower median waitlist time (Pre: 88 [29-190] days versus Post: 22 [7-69] days, p < 0.001), and a higher proportion of transplanted patients (Pre: 65% versus Post: 85%, p < 0.001). Both waitlist survival (p < 0.001) and post-transplant survival (p = 0.05) improved after the policy change.

The 2018 policy revision was associated with a decline in biventricular support utilization in both waitlisted and transplanted cohorts. This shift corresponded with shorter waitlist durations, more frequent transplants, and better waitlist and post-transplant survival.