Is a Bioimpedance Assay an Effective Tool for Evaluating Cardiac Parameters in Patients with ESKD Undergoing Hemodialysis? A Cross-Sectional Study from North India

Background: Hemodynamic stress caused by either fluid overload or depletion is a major contributor to cardiac complications in dialysis. Study aimed to investigate the role of BIA in assessing fluid status and its correlation with cardiac parameters in hemodialysis patients. Methods: In cross-sectional study, 39 patients with ESKD undergoing hemodialysis at least three times a week for three months and had a preserved ejection fraction (EF>40%) were enrolled. Exclusion criteria included patients undergoing diuretics those with sepsis, limb amputations, pacemakers, metallic intravascular devices, malignancies, or pregnancy. The study investigated the levels of N-terminal pro-b-type natriuretic peptide (NT-pro BNP) and performed echocardiography (ECHO-2D) before and after hemodialysis. Hydration status of patients was assessed using 4-electrode BIA device (Fresenius Medical Care, Germany). This was done before dialysis, 30 minutes after dialysis, and before subsequent dialysis. Patients categorized into two groups based on hydration status: Group-A had overhydration (OH/ECW ratio ≥15%), while Group-B had normal hydration (OH/ECW ratio<15%). Results: Among 39 patients, 69.2% were in Group A, while remaining 30.8% were in Group B. Mean age was 57.3±11.4 years for Group A and 54.0±16.3 years for Group B. Both groups matched for age, sex, BMI, biochemical, hemodynamic, and echocardiographic parameters. Before and after dialysis, no significant differences observed in various cardiac parameters between two groups, except for changes in aortic root diameter, left atrial diameter, and A wave velocity in Group A. NT-proBNP levels showed a significant decline after dialysis in groups A and B (p0.001). Hydration status (OH/ECW) before dialysis exhibited a negative correlation with left ventricular ejection fraction (LVEF)(r-0.434,p0.006) and NT-proBNP levels (r-0.708,p0.001). Post-dialysis OH/ECW displayed a negative correlation with LVEF(r-0.744,p0.001), and peak late transmitral filling wave velocity (A)(r-0.342,p0.033). Conclusion: BIA-evaluated hydration levels were correlated with LVEF. By controlling OH/ECW during BIA-guided dialysis, we can potentially reduce the risk of cardiac morbidity.