Background: The United Network for Organ Sharing (UNOS) adopted new criteria for the heart allocation score on 10/18/2018 to reflect changing trends of candidates' mortality while awaiting transplant. We examined the impact of these policy changes on rates of left ventricular assist device (LVAD) implantation and outcomes post-transplant from a relatively newer UNOS database. Methods: The UNOS registry was used to identify heart recipients with LVAD who underwent transplantation between 1/1/2016 and 3/10/2020. Survival data was collected through 3/30/2023. Those listed prior to 10/18/2018 but transplanted after were excluded. Patients were divided into before or after change groups. Demographics and clinical parameters were compared. Survival was analyzed with Kaplan-Meier curves and log-rank tests. Results: We identified 4599 heart recipients with LVAD in the before (N=3767) and after (N=832) score change eras. The after-group had a lower rate of LVAD implantation while listed compared to the before-group (19.4% vs 34.5%, p<0.0001). There was significantly farther distance from the donor hospital to transplant center in the after-group (259.5 ± 246.8 NM vs 143.2 ± 182.1 NM, p<0.0001) and decreased waitlist days (83.5 ± 103.5 vs 369.0 ± 458.5, p<0.0001). Recipients in the after-group were more likely to receive a CDC increased-risk donor organ (37.5% vs 30.2%, p=0.0002). Survival at 5-years was significantly reduced in the after-group (60.5% vs 78.9%, p<0.0001). Conclusions: The allocation score change in 2018 yielded considerable changes in mechanical circulatory support device implantation strategy and survival. The rate of LVAD implantation decreased with profoundly worse 5-year survival, showing further divergence from prior short-term post-transplant data.

The authors have declared no competing interest.

This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

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The data that support the findings of this study are available from the United Network for Organ Sharing