This study adds another category of patients to those amenable to body impedance analysis (BIA). BIA measurements were obtained for the first time in 23 male patients with end-stage heart failure who were waiting for heart transplantation, and the data were compared with those obtained in 69 healthy controls matched for age, sex, height and weight. The data indicate that in end-stage heart failure there is an increased reactance (p<0.01) and an altered intracellular water/extracellular water ratio (p<0.03) due to the increased intracellular water (p<0.01) and decreased extracellular water (p<0.01).