Impact of Intradialytic Weight Gain on Left Ventricular Function and Characteristics in Hemodialysis Patients.

Background: Pulmonary circulation is particularly overloaded in hemodialysis patients with high interdialytic weight gain (IDWG), as evidenced by deterioration in right ventricular function indices. This study aimed to evaluate the impact of the degree of fluid accumulation on left ventricular (LV) systolic and diastolic function and sizing characteristics.

Methods: This is a post hoc analysis of a cross-over study in 41 hemodialysis patients. Study participants were stratified using the recommended threshold IDWG% into a higher (> 4.5%) and a lower (< 4.5%) IDWG% group. All participants underwent 4 echocardiographic assessments at the start and the end of the 2-day and the 3-day interdialytic interval.

Results: Over the 2-day interval, stroke volume and cardiac output increments were more prominent in the higher IDWG% group (> 4.5% 22.97 ± 18.45 vs. < 4.5% 0.95 ± 29.1 mmHg, p = 0.006; > 4.5% 1.32 ± 1.39 vs. < 4.5% -0.36 ± 2.08 L/m, p = 0.004, respectively). Over the 3-day interval, significant increments in stroke volume were observed for both groups. With regard to diastolic function, a significant increase in E wave, E/A, and E/E'm lateral ratios was observed over the 3-day interval, and significant between-group differences in interdialytic changes were detected for the E/A ratio (IDWG > 4.5% 0.35 ± 0.29 vs. < 4.5% 0.06 ± 0.44, p = 0.035) and the E wave (IDWG > 4.5% 0.31 ± 0.24 vs. < 4.5% 0.10 ± 0.19, p = 0.02). Left atrial dimensions and LV mass were enlarged to a similar extent in both study groups during both intervals.

Conclusions: Patients exceeding the recommended IDWG threshold experience more pronounced changes in indices of LV function and significant deterioration of preload-dependent indexes of LV diastolic function.