Association of Donor Brain Death Due to Stroke With Prognosis After Heart Transplantation

Background: The proximate cause of donor brain death is not considered a conventional risk factor in modern heart transplantation. Objectives: This study aimed to investigate the effect of the cause of donor brain death on recipients. Methods: Using the United Network for Organ Sharing registry, long-term mortality and allograft failure were compared in recipients who underwent heart transplantation in the United States from 2005 through 2018 between allograft recipients from donors with stroke as the cause of brain death (n = 3,761) vs nonstroke causes (n = 14,677). Inverse probability weighting was used for risk adjustment. Interactions were investigated between the cause of brain death and other conventional donor risk factors for recipient mortality. Results: There was an interaction between the cause of brain death and donor age (P_interaction = 0.008). When allografts were procured from donors aged 40 years or younger, stroke as the cause of brain death was associated with an increased risk of mortality (23% vs 19% at 5 years; HR: 1.17; 95% CI: 1.02-1.35) and allograft failure (HR: 1.30; 95% CI: 1.04-1.63). When donors were older than 40 years, the cause of brain death was not associated with outcomes. Conclusions: As the cause of donor brain death, stroke had a substantially different effect on recipient and allograft survival depending on donor age. In the case of younger donor ages, stroke was associated with higher recipient mortality and allograft failure than other causes of brain death. The strength of this association decreased with increasing donor age such that the increased hazard was no longer present in donors older than approximately 40 years.