We studied 193 patients free of heart disease to determine the relation between QRS amplitude and serum albumin. Although there were no significant differences in echocardiographic indexes between the 2 groups, albumin (35.1 +/- 4.3 vs 40.1 +/- 3.2 g/L) and colloid osmotic pressure (21 +/- 4 vs 24 +/- 3 mm Hg) were significantly lower in patients with low voltages compared with those without. Moreover, there was a good relation (r = 0.78) between change in QRS amplitude and change in albumin concentration.