Estimation of pulse arrival time using impedance plethysmogram from body composition scales

Long-term periodic monitoring of cardiovascular function in unobtrusive way has been a challenge in sensor research lately. This work presents the investigation of the method for pulse arrival time (PAT) estimation using body composition scales. It employs the electrocardiogram and the impedance plethysmogram (IPG) which are recorded from palm and plantar electrodes already integrated into body composition scales. Four subjects were involved in the experiment. The IPG was acquired from a single-foot and foot-to-foot and compared to the reference method - photoplethysmography. The range of correlation coefficient obtained in different methods varied from 0.7 to 0.94 showing that small PAT variations can be tracked using the IPG signals. Such results suggest that body composition scales could be supplemented with additional parameter for the assessment of arterial stiffness. This function will make them truly multi-parametric device for periodic health monitoring at home.