Possibilities of instrumental determination of volemic status in patients with acute decompensation of chronic heart failure

Aim. To evaluate and compare the accuracy of volemic status determination by remote dielectric sensing with computed tomography (CT) in patients with acute decompensated heart failure.

Materials and methods. In 28 patients volemic status was determined by ReDS (remote dielectric sensing), chest computed tomography (CCT), and chest X-ray twice during hospitalization (the day of admission and the day of discharge from the hospital). The ReDS measurements were then compared with CT data using software that allows the use of semi-automated tools to determine mean lung density (MLD). MLD results from Hounsfield Units [HU] were then converted to fluid levels (FU%), allowing them to be compared with ReDS values. In addition, to assess the effect of physical activity on the dynamics of pulmonary stasis there was performed 6-minute walk test (6MWT) followed by determination of volumic status by ReDS method.

Results. Correlation analysis revealed an average direct significant correlation (r=+0,5; p=0.001) between the CCT and ReDS data. Hypervolemia indexes according to the CCT revealed statistically significant decrease in the dynamics, which was also reflected in the ReDS index decrease. Lung fluid content according to ReDS averaged 38.2±4.6% on admission, and 34.5±3.9% on discharge (p=0.005). According to CT scan of the CCT, MLD at admission was 23.03±3.9%, at discharge 19.6±3.3% (p=0.003). The positive dynamics of the study methods was also reflected in the positive dynamics of NT-proBNP, which decreased by 46%. In the analysis of ReDS data before and after exercise, there was an increase in ReDS value after the performed 6MWT and it was 35.09±3.9% compared with the initial value of 34.5±3.9%. A strong direct significant correlation (r=+0.7; p=0.0001) was found between the ReDS before and after 6MWT at discharge.