Body weight and serum lipids were retrospectively analyzed in 54 heart transplant recipients (mean age, 43 years; 80% male) who survived at least 1 year. Data were collected preoperatively and at 1, 2, and 3 years after heart transplantation. Analysis was performed using item frequencies, analysis of variance, and Pearson product moment correlations. From preoperatively to 1 year after heart transplantation, the weight of patients increased significantly from 100% to 117% of ideal body weight and did not decrease significantly over the first 3 postoperative years. Serum cholesterol and triglyceride values increased significantly from preoperative values of 175 mg/dl and 139 mg/dl, respectively, to 1-year postoperative values of more than 200 mg/dl (p = 0.01). Serum cholesterol, but not triglyceride levels, decreased significantly 3 years after surgery as compared with 1 year after surgery. In addition, overall serum cholesterol and triglyceride levels were higher in patients with coronary artery disease (248 mg/dl) than with dilated cardiomyopathy (207 mg/dl). Serum high-density lipoproteins remained within acceptable clinical levels (greater than 35 mg/dl) during all 3 postoperative years. Serum low-density lipoproteins, elevated (139 mg/dl) for the first 2 postoperative years, fell to within the desirable range (less than 130 mg/dl) by the third posttransplant year. Heart function was normal throughout all 3 years. Six patients (11%) were given lipid-lowering medications after heart transplantation (mean, 25 postoperative months).(ABSTRACT TRUNCATED AT 250 WORDS)