Background: Left atrial volume index (LAVi) is reported as an independent parameter of cardiovascular risk in the clinical course of hemodialysis (HD) patients. Volume dependency of functional parameters of LA evaluated by color Doppler tissue and strain imaging is largely unknown. Methods: Echocardiogram examinations were obtained just before and after HD in 41 patients on a regular schedule of HD. Atrial strain and strain rate (SR) values were obtained at selected narrow sample volume. Peak strain SR were measured in late diastole in the basal septal, inferior, lateral and anterior walls of the atrium from the apical 4 and 2-chamber views. Results: LAVi (Pre-HD 46.55짹15.91: Post-HD 38.55짹14.67 mL/m2, p<0.001), LA minimal volume (Pre-HD 21.50짹10.11: Post-HD 16.21짹8.47 mL/m2, p<0.001), and pre-P wave LA volume (Pre-HD 31.90짹13.71: Post-HD 26.73짹12.93 mL/m2, p<0.001) were all decreased after HD. There were also significant differences in LA passive emptying volume (Pre-HD 14.65짹7.70: Post-HD 11.82짹5.89 mL/m2, p=0.004) and conduit volume (Pre-HD 20.31짹7.35: Post-HD 16.93짹6.47 mL/m2, p=0.016) but not in LA active emptying volume (Pre-HD 10.41짹6.01: Post-HD 10.52짹6.78 mL/m2, p=0.728). Aa was not different between pre- and post-HD (Pre-HD 6.34짹1.58: Post-HD 6.46짹1.54 cm/s, p=0.4368). Average values of LA peak were significantly decreased but peak SR did not change after HD (Table 1). Conclusion: The peak strain of LA was significantly decreased after HD but there were no differences of late diastolic peak strain rate. These findings demonstrated that acute volume change affected atrial reservoir but not contractile function as shown in phasic volume and color Doppler tissue study. They also suggest that strain is not a volume-independent parameter for the evaluation of LA function.