Noninvasive hemodynamic monitoring in heart failure: utilization of impedance cardiography

The annual health care cost incurred by heart failure patients is about $56 billion, two thirds of which is spent on management of acutely decompensated patients. Hemodynamic evaluation is helpful for optimization of treatment, monitoring clinical outcomes, and overall prognostication of heart failure patients, but historically could only be obtained via costly invasive procedures that carry substantial risks. Impedance cardiography (ICG) is a noninvasive and economical outpatient procedure that has been shown to provide reliable hemodynamic values comparable to those obtained from pulmonary artery catheterization. Recent clinical studies involving hundreds of patients have validated the accuracy and reproducibility of ICG compared with invasive techniques. The direct and derived measurements and the clinical applications of ICG in the diagnosis and treatment of heart failure are presented, as are three clinical case studies demonstrating the utility of ICG in the hemodynamic-guided management of heart failure. ICG is a viable, noninvasive technique in early- and late-stage heart failure that provides assistance in diagnostic evaluation, longitudinal prognostication, and therapeutic decisions.