Although the etiology of allograft coronary artery disease, a major limiting factor in long-term survival after cardiac transplantation, is poorly understood, it is undoubtedly in part immune mediated and not detected by routine endomyocardial biopsy. Therefore it is possible that withdrawal of maintenance corticosteroids, although providing other short- and long-term benefits, could increase the prevalence of allograft coronary artery disease by permitting undetected immune-mediated vascular injury to occur. To assess whether corticosteroid-free maintenance immunosuppression increased the prevalence of allograft coronary artery disease, we reviewed serial angiograms of 102 patients (49% not receiving corticosteroid maintenance therapy) who underwent heart transplantation after March 7, 1985. Multiple variables including serum cholesterol, recipient and donor age, sex, blood pressure, rejection frequency and severity, early rejection prophylaxis protocol (polyclonal versus monoclonal T-cell agents), and corticosteroid use were examined in relation to allograft coronary artery disease by univariate and multivariate analyses. Allograft coronary artery disease was identified in 21 patients (seven severe, four moderate, and 10 mild). The prevalence by Kaplan-Meier life-table analysis was 17% at 1 year and 25% at 2 years. No further allograft coronary artery disease was detected among patients undergoing angiography at three years. Increased allograft coronary artery disease was not noted in patients withdrawn from maintenance corticosteroids when compared with their corticosteroid-requiring counterparts. In fact, with each 1 gm increment in cumulative corticosteroid use, a slightly increased risk (1.04, p less than 0.05) of allograft coronary artery disease was noted (Cox regression model). None of the other variables correlated with the prevalence of allograft coronary artery disease. Thus withdrawal of maintenance corticosteroids is not associated with an increased risk of early allograft coronary artery disease and minimization of corticosteroids may lead to a decreased long-term incidence of coronary artery disease in cardiac transplant recipients.