Cardiovascular haemodynamics and circulating catecholamines were studied in 22 patients with cirrhosis. Arterial plasma noradrenaline (NA) was significantly increased (median, 0.48 ng/ml, versus controls, 0.24 ng/ml; n = 17; P less than 0.001), indicating enhanced sympathetic nervous activity. Heart rate was also increased (88 min-1 versus controls, 68 min-1; P less than 0.001), and mean arterial blood pressure was significantly decreased (81 mm Hg, versus controls, 88 mm Hg; P less than 0.002). Cardiac output was above the upper reference limit in eight patients and below the lower limit in two patients. Arterial NA was inversely correlated to stroke volume (r = -0.55; P less than 0.01) and to cardiac output (r = -0.53; P less than 0.02). Statistically significant relationships could not be demonstrated between NA and heart rate, arterial blood pressure, or right atrial pressure, but NA was slightly positively correlated to systemic vascular resistance (r = 0.51; P less than 0.02). The results may suggest that a relatively insufficient cardiac performance in the hyperkinetic circulatory state in cirrhosis may elicit an enhanced sympathetic nervous activity, which may contribute to maintenance of cardiovascular homeostasis.