Relationship Between Noninvasive Assessment of Lung Fluid Volume and Invasively Measured Cardiac Hemodynamics

Background Right heart catheterization is the gold standard in clinical practice for the assessment of cardiovascular hemodynamics, but it is an invasive procedure requiring expertise in both insertion and reading. Remote dielectric sensing (Re DS ) is a noninvasive electromagnetic-based technology intended to quantify lung fluid content. Methods and Results In this prospective single-center study, Re DS readings were obtained in supine position just before right heart catheterization procedure in patients with heart failure. Agreement between Re DS and pulmonary artery wedge pressure ( PAWP ) was analyzed. Of all, 139 patients with heart failure received hemodynamic assessment and Re DS measurement. A good correlation was found between Re DS and PAWP measurement ( r=0.492, P<0.001). Receiver operating characteristic analysis of the ability to identify a PAWP ≥18 mm Hg resulted in a Re DS cutoff value of 34%, with an area under the curve of 0.848, a sensitivity of 90.7%, and a specificity of 77.1%. Overall, Re DS <34% carries a high negative predictive value of 94.9%. Conclusions Lung fluid content, as measured by Re DS , correlates well with PAWP . The high sensitivity and specificity and especially the high negative predictive value make Re DS a reliable noninvasive tool at the point of care, to rule out elevated PAWP in patients with heart failure and to help with medical management of patients with heart failure. Further studies are warranted to compare this tool with existing tests and to relate the findings to the clinical outcomes.