Abstract: Method and apparatus for estimating an arrival time (PAT) value of a subject in an automatic and unsupervised fashion from a sequence of electrical impedance tomography (EIT) images. The method comprises: providing an EIT imaging device adapted to record impedance signal distribution within a measurement region of the subject; measuring a sequence of temporally discrete EIT images during a predetermined measuring time period in the measurement region using the EIT imaging device, each EIT image comprising one or a plurality of EIT pixel subsets, each of said one or a plurality of EIT pixel subset representing an impedance value; generating one or a plurality of time series, each of said one or a plurality of time series representing a variation of the impedance value of the sequence of EIT images; and estimating the PAT value from each of said one or a plurality of time series.

Abstract: Method and apparatus for measuring a pulse transit time (PTT) value of a subject, comprising: measuring a first arterial pressure pulse arrival time (PAT) and measuring a second PAT value; calculating a PTT value from the difference between the first PAT value and the second PAT value; processing a sequence of electrical impedance tomography (EIT) images to identify at least one region of interest (ROI); and estimating at least one of the first and second PAT value from the variation of impedance value determined from said at least one ROI. The method allows for the non-invasive and continuous measurement of the PTT value and arterial blood pressures.

Abstract: A method for measuring and determining a pulse arrival time (PAT) value of a user using a sensor device comprising a photoplethysmographic (PPG) multichannel sensor formed from a plurality of PPG sensor channels and being adapted to measure a set of PPG signals, each PPG signal being measured by one of the PPG sensor channels when the multichannel PPG sensor is in contact with the user; comprising: measuring said set of PPG signals; extracting a plurality of features from each of the measured PPG signals; selecting a subset from the set of PPG signals based on the extracted features; and processing the selected subset of PPG signals to determine the PAT value. The disclosed sensor and method can be embedded into a chest belt and do not need skilled supervision. They can represent a potential candidate for the implantation of PWV measurement campaigns in the ambulatory setting.