Beneficial effect of female gender on long-term survival after heart transplantation

BACKGROUND: We aimed to test whether stenotic microvasculopathy affects the more beneficial course in female cardiac transplant recipients. METHODS: We studied 873 patients (35/151 premenopausal women aged < or =40 years) who underwent primary heart transplantation. In 7750 biopsies harvested within the first posttransplant year endothelial disease and stenotic microvasculopathy were evaluated by light microscopy (Hematoxylin and Eosin). Kaplan-Meier and Cox regression analyses were performed for major cardiac events (MACE; lethal myocardial infarction, sudden cardiac death, graft failure, and cardiac retransplantation). RESULTS: Stenotic microvasculopathy was found equally in men (38%) and women (39%). Allografts from premenopausal female-to-male transplants more frequently developed endothelial disease (78% vs. 65%; P=0.021) and stenotic microvasculopathy (46% vs. 28%, P=0.024). Beyond the first 5 posttransplant years women presented MACE less often than men, independently of donor gender and stenotic microvasculopathy (P=0.0001). Multivariate regression analysis found women to be at lower risk for MACE (Relative Risk [RR] 0.38; 95% Confidence Interval [CI] 0.17-0.81), whereas stenotic microvasculopathy (RR 2.15; 95% CI 1.42-3.26) and treated diabetes (RR 1.65; 95% CI 1.08-2.52) indicated a higher risk for MACE. CONCLUSIONS: Stenotic microvasculopathy has prognostic impact on survival of male and female cardiac recipients; however, it does not affect the more beneficial course of women in the long-term follow-up.