Systemic hemodynamic impairment (hepatocirculatory failure) has been suggested as one of the possible factors which may explain the renal hemodynamic alterations found in the late stage of liver cirrhosis, typical of the hepatorenal syndrome. 20 patients, divided into two groups of 10 sodium retainers and 10 sodium excretors, affected by liver cirrhosis with portal hypertension and ascites, were studied. Renal functional parameters (diuresis, urinary and plasma electrolytes, urine to plasma osmolality and creatinine ratios and creatinine clearance) were evaluated before and after acute volume expansion with 1,000 ml of 10% dextran in saline, infused through a catheter located in the right atrium. Hemodynamic tests (cardiac index, systemic vascular resistance, right atrial pressure and capillary wedge pressure) were performed before, during and after expansion. Cardiac index decreased in 6 patients (sodium excretors) after a 500-ml infusion and rose again after 1,000 ml in 5 of them. The remaining 14 patients showed a progressive and significant increase of cardiac index. A strong inverse relationship between cardiac index and systemic vascular resistance was observed (r = -0.87; p less than 0.001). The mean left-ventricular function curve showed a slow response in most sodium excretors and a normal response in the sodium-retaining group, without significant difference between the two groups. Sodium excretion significantly improved after expansion in both groups of patients. No relationship was found between hemodynamic response and renal function. These data show that cardiocirculatory function is normal, even in sodium-retaining cirrhotics.