Influence of HLA-DR Mismatches on Long Term Outcomes Following Heart Transplant

Purpose There are conflicting reports on the effect of donor-recipient HLA-DR matching in heart transplantation. Studies have shown HLA-DR matching reduces the incidence of graft rejection within the first year and improves short term graft survival It is not known if HLA-DR matching impacts long term outcomes. We sought to analyze the effect of HLA-DR mismatch on long term survival, and also explain possible mechanisms. Methods All adult heart transplants performed at our institution from 2000 to 2010 were retrospectively reviewed. Multi-organs, patients who expired within the first year after transplant and those with missing data were excluded. Patients were grouped according to number of HLA-DR mismatches: 0, 1 or 2. We analyzed allograft function [using most recent ejection fraction (EF)], development of significant (ISHLT grade ≥2) cardiac allograft vasculopathy (CAV) and survival. ANOVA used for analysis. Kaplan-Meier survival curves generated. P value Results 172 heart transplant recipients were included in the analysis. HLA-DR mismatch status was as follows: 9 (5.2%) had 0, 63 (36.6%) had 1, and 100 (58.1%) had 2 mismatches. There were more men in the group with 2 mismatches (82% vs 74.6% vs 66.7%, P Conclusion In our cohort, HLA-DR mismatches did not influence graft function, development of and severity of angiographically significant CAV. There was no impact on long term patient survival. HLA-DR matching prior to heart transplant may not be justified given the increased cost and logistical burden of HLA matching and longer cold‐ischemic times that may result from reliance on tissue typing.