Feasibility Of Non-invasive Bioelectrical Impedance Analysis To Estimate Lung Fluid Status In Patients With And Without Acute Heart Failure

초록

Background Outpatient monitoring of pulmonary congestion in patients with heart failure (HF) might reduce rates of hospitalization. This study aimed to test the feasibility of non-invasive bioelectrical impedance analysis (BIA) to estimate the lung fluid status. Methods The study included 70 subjects: 50 acute decompensated HF inpatients (HF group) and 20 subjects without HF (control group). All patients underwent supine chest CT scan to quantify lung fluid content using lung density analysis software and direct segmental multifrequency BIA for measurement of edema index (EI, extracellular water/total body water) in the trunk and whole body. InBodyS10 using 1-1000kHz and BWA2.0 using 1-3000kHz were used as tools for BIA. Results The correlation coefficients between lung fluid content and EI measured with InBodyS10 and BWA2.0 were r=0.527 and r=0.568 (both p <0.001) in the trunk, respectively, and r=0.510, r=0.549 (both p<0.001) in the whole body, respectively. In the HF group, the trunk EI (0.402-0.408) and whole-body EI (0.402-0.406) were significantly higher than those of the control group (trunk EI, 0.380-0.383; whole-body EI, 0.380-0.383, all p<0.001). The lung fluid content using chest CT was also significantly higher in HF group than that of the control group (22.3±6.2% vs. 13.3±3.4%, p<0.001). The log value of NTpro-BNP was significantly correlated with trunk EI measured by InBodyS10 and BWA2.0 (r=0.669 and r=0.588, respectively, both p <0.001), whole-body EI (r=0.644 and r=0.562, respectively, both p<0.001), and the lung fluid content using chest CT (r=0.653, p <0.001). Conclusions BIA-based EI measurement in the trunk and whole-body was significantly correlated with lung fluid content and NTpro-BNP. Non-invasive BIA could be a promising tool for monitoring lung fluid status in patients with HF. Key words: Lung congestion; Heart failure; HF-BIA; lung fluid content; chest CT; edema index.