Analysis of the Arterial Pulse Wave Time Features and Pulse Wave Velocity Calculations Based on Radial Electrical Bioimpedance Waveforms in Patients Scheduled for Cardiac Catheterization

Monitoring of peripheral electrical bioimpedance (EBI) variations is a promising method that has potential to replace invasive or burdensome techniques for cardiovascular measurements. Segmental or continuous peripheral pulse recording can be substrate for calculating prognostic markers as pulse wave velocity (PWV) or can contain substrates as pulse transit time (PTT) or pulse arrival time (PAT) for undisturbing BP calculation or even new cardiovascular risk markers. Still several technical, analytical, and interpretative aspects need to be resolved before the EBI method can be adopted in clinical practice. Our goal was to investigate and improve application of the EBI, executing its comparison with other cardiovascular assessment methods in patients hospitalized for coronary catheterization procedure; Methods: We analyzed data from 44 non-acute patients aged 45-74 years hospitalized for coronary catheterization in East-Tallinn Central Hospital in 2020-2021. The radial EBI and ECG were measured simultaneously with contralateral radial and central pressure curves. The Savitzky–Golay filter was used for signal smoothing. The Hankel matrix decomposer for extraction of cardiac waveforms from the multi-component signals was applied. After extracting the cardiac component, a period detection algorithm was applied to EBI and blood pressure curves; Results: We were able to detect seven points on the pressure and EBI curves, five with good representativeness were selected for further analysis. Spearman correlation coefficient was low for all but the central and distal pressure curve systolic upstroke time points. High positive correlation was found between PWV measured both invasively and with EBI. High positive correlation was found between invasive and noninvasive PWV calculations. Median CPWV was significantly lower in patients with normal coronaries compared to patients with any stage of coronary disease; Conclusions: With regard to wearable devices, the EBI derived PAT can serve as a substrate to PWV calculations and cardiovascular risk assessment, although these data require further confirmation.