To determine whether the onset of coronary artery disease may precede the initiation of dialysis in patients with end-stage renal disease, we performed coronary angiography within 1 month of initiation of maintenance haemodialysis in 24 patients (age range 42-78 years; mean 63.7 +/- 11). Coronary angiography was performed regardless of the absence or presence of angina. Fifteen patients had diabetic nephropathy, and nine had non-diabetic nephropathy. Significant coronary stenosis was defined as at least 75% narrowing of the reference segment. Fifteen patients (62.5%) with a total of 49 lesions were classified as the coronary artery disease present group. Eleven of those 15 (73.3%) had multivessel disease. The average number of stenotic lesions was 3.3 per patient. The most common patterns of stenosis were complex (23 lesions; 47%), and diffuse lesions over 20 mm long (14 lesions; 29%). None of the clinical or haematological factors evaluated differed significantly between the groups with and without coronary artery disease. The prevalence of coronary artery disease was 72.7% in the symptomatic patients and 53.8% in the asymptomatic patients. The diagnosis of coronary artery disease at the start of maintenance haemodialysis based only on chest symptoms and clinical factors proved to be difficult. Coronary angiography is thus essential for evaluating coronary artery disease in uraemic patients. Many patients with end-stage renal disease had coronary artery disease prior to the start of haemodialysis.