Background and Purpose: Despite more than 20 years of experience in heart transplantation, the risk factors for development of chronic renal insufficiency in recipients arc not well established. This study assessed the incidence, prognosis and risk factors-for renal dysfunction after heart transplantation. Methods: We-conducted a retrospective analysis of all adult patients (n=132) who survived for more than 1 year after hart transplantation at our institutions from March 1992 through November 2002. Renal dysfunction was defined as serum creatinine of ≥2.0 mg/dL. The incidence and prognosis of renal dysfunction after heart transplantation was estimated by the Kaplan-Meier method and compared by log rank test. Risk factors for renal dysfunction, at 1 year after transplantation were evaluated using a logistic regression model. Results: Renal dysfunction was present in 9 patients (7%) before heart transplantation. The cumulative incidence of renal dysfunction after heart transplantation was 23.0±3.8%, 36.1±4.3%, 53.9±4.9%, and 57.3±5.8% at 6 months, 1 year 5 years and 10 years, respectively, after transplantation. The actuarial survival rate in patients without renal dysfunction at 1 year after transplantation was better than for patients with renal dysfunction at 1 year after transplantation (p=0.046 by log- rank test). Independent risk factors for renal dysfunction at 1 year after transplantation were age at transplantation (odds ratio, 1. 07; p=0.02), pretransplant serum blood urea nitrogen (odds ratio, 1.07; p=0.048), and serum creatinine at 6 months after transplantation (odds ratio, 17.0; p