Non-Invasive Measurement of Hemodynamic Parameters via Whole-Body Impedance Cardiography Among Hospitalized Heart Failure Patients: An Effective Alternative to Invasive Right Heart Catheterization?

(1) Background: The measurement of hemodynamic parameters has proven to be crucial in the treatment of hospitalized heart failure patients, necessitating invasive measurement by right heart catheterization (RHC). The reliability of whole-body impedance cardiography (ICG) among this cohort has not been investigated to date; (2) Methods: The RHC and whole-body ICG examinations measured cardiac output (CO), the cardiac index (CI), total peripheral resistance (TPR), and pulmonary vascular resistance (PVR). To assess the accuracy of the whole-body ICG measurement, bias and precision were calculated as the mean difference and the twofold standard deviation between the average values of measurements; (3) Results: A total of 203 patients were analyzed. No significant bias was observed between the non-invasive CO and CI measurements when compared with the RHC measurements (-0.14 ± 2.56 L/min, p = 0.1; -0.09 ± 1.3 L/min/m², p = 0.06), but a significant bias occurred in the measurement of non-invasive TPR and non-invasive PVR (-1243 ± 3510 dyn × s^-1 × cm^-5, p = 0.001; -121 ± 504 dyn × s^-1 × cm^-5, p < 0.001); (4) Conclusions: CO and CI can be measured with whole-body ICG among hospitalized CHF patients with acceptable accuracy. The reliability of measuring TPR and PVR should be further investigated.