Validation of Cor-IS Impedance Spectroscopy Against Ultrasound Flow-Mediated Dilation

This prospective observational study evaluated the Cor-IS bioelectrical impedance spectroscopy technique for the assessment of endothelial function by comparison with ultrasound-based brachial artery flow-mediated dilation (FMD). A total of 208 participants were enrolled and classified into three groups according to their cardiovascular profile: healthy controls, individuals with cardiovascular risk factors, and patients with acute myocardial infarction. Each participant underwent endothelial function assessment using both ultrasound-based FMD and the Cor-IS technique under standardized conditions. The primary objective was to evaluate the correlation and agreement between measurements obtained using Cor-IS and ultrasound-based FMD. Secondary objectives included comparing endothelial function measurements across the three study groups and evaluating their associations with selected clinical and demographic characteristics.