Donor coronary artery disease and outcomes after heart transplantation: Effect modification by donor age and allocation era.

BACKGROUND

The limited availability of donor hearts has led to an increased utilization of organs from donors with pre-existing coronary artery disease (CAD). However, the impact of donor-transmitted CAD (DTCAD) on post-transplant outcomes stratified by donor age remains insufficiently characterized.

METHODS

Using the United Network for Organ Sharing database, adults undergoing orthotopic heart transplantation (2000 to 2025) were analyzed. Donors were stratified by age and CAD status on pre-procurement angiography. The primary outcome was all-cause mortality. Effect modification by donor age and allocation era was assessed using multivariable Cox regression.

RESULTS

Among 21,805 recipients (median follow-up 3.94 years), 1932 (8.9%) received hearts with CAD. DTCAD was not associated with mortality [hazard ratio (HR) 1.04; 95% confidence interval (CI) 0.95-1.13; p = 0.38]. The CAD × donor age interaction met the prespecified threshold (p = 0.094), with increasing risk among older donors (HR 1.27 at age 60; p = 0.02). Significant effect modification by allocation era was observed (interaction p = 0.018): DTCAD was not associated with higher mortality pre-2018 (HR 0.97) but was associated with a 24% increase in mortality post-2018 (HR 1.24; 95% CI 1.07-1.43; p = 0.005). Secondary outcomes, including graft failure, treated rejection, stroke, dialysis, and pacemaker implantation, did not differ between groups.

CONCLUSIONS

DTCAD is not consistently associated with adverse outcomes. However, in the current era characterized by higher-acuity recipients, DTCAD, especially from older donors, is linked to increased mortality. These findings support re-evaluating donor CAD selection criteria in contemporary practice.