The effect of donor distance on post-transplant mortality in the modern era

In the new US heart transplant allocation system, eligible patients can receive hearts from donors beyond a 250-mile radius. The safety of extended travel and its impact on ischemic time are poorly understood. This study examines post-transplantation mortality based on distance between donor and transplant centers.

Adult patients listed as status 1 or 2 for isolated heart transplantation between October 18, 2018, and September 30, 2023, who subsequently received an organ were identified in the United Network for Organ Sharing database. Patients were stratified by donor distance (≤250 or >250 miles). Linear and logistic models analyzed the relationships among 1-year survival, distance, and ischemic time. The 1-year mortality was further characterized by Kaplan-Meier analysis.

Of the 5315 patients included in this cohort, 45% received hearts within a 250-mile radius, and 55% received hearts from distances beyond 250 miles. The majority of patients were male and White, and had dilated cardiomyopathy. Assessment of the relationship between distance and ischemic time showed an 18-minute increase for every additional 100 miles of travel. Multivariable logistic regression indicated increased mortality with longer ischemic times, but no difference in survival with increasing distances. Further, on multivariable time-dependent analysis, increasing ischemic time was a predictor of mortality (odds ratio, 1.19 [1.01-1.21]), whereas increased donor distance was not (odds ratio, 0.84 [0.68-1.04]).

Distance between donor and transplant center minimally affected ischemic time and showed no impact on post-transplant 1-year survival. Therefore, ischemic time limitations rather than distance cutoffs may be more appropriate for policies regarding heart procurement.