BACKGROUND: Impaired fibrinolytic activity has been linked to the presence and severity of allograft vasculopathy (Tx CAD). This impairment may be associated with the presence of certain fibrinolytic protein gene polymorphisms. METHODS AND RESULTS: To investigate the relation between donor-specific fibrinolytic protein genotypes and Tx CAD, we identified donor plasminogen activator inhibitor-1 (PAI-1) HindIII and tissue plasminogen activator (TPA) EcoRI restriction fragment length polymorphisms-based genotypes by Southern blot analysis in 48 recipients of cardiac allografts and correlated these genotypes with the development of CAD. No association was found between donor TPA genotypes and the presence of Tx CAD. Among the 48 patients, 17% were homozygous for the 1/1 PAI-1 genotype, 51% for the 2/2 PAI-1 genotype, and 32% for the 1/2 PAI-1 genotype. The actuarial freedom from any CAD for the recipients with each respective donor PAI-1 genotype at 12 and 24 months was 100% and 100% for the 1/1 PAI-1 genotype, 92% and 92% for the 1/2 PAI-1 genotype, and 75% and 45% for the 2/2 PAI-1 genotype (P=0.03). Recipients with a diseased 2/2 PAI-1 genotyped allograft had longer ischemic times (P=0.02) than those recipients with a Tx CAD-free allograft. CONCLUSIONS: These data suggest that recipients with a 2/2 PAI-1 genotype are at a significant risk of developing Tx CAD. This genotype may serve as a useful screening tool for predicting the future development of Tx CAD.