title: A chair for cuffless real-time estimation of systolic blood pressure based on pulse transit time.
abstract: This study presents an unobtrusive cuffless blood pressure (BP) monitoring system for estimating beat-by-beat systolic blood pressure (SBP) in real-time based on pulse transit time (PTT). The system mainly includes an electrocardiograph with three conductive textile electrodes, a pulse monitor with a LED and a photodetector, a control circuit with a Bluetooth module, and a battery, all of which are mounted on a common armchair to measure ECG and photoplethysmography (PPG) signals from users during sitting on the armchair. The measured ECG and PPG data are transmitted to the software terminal installed on a tablet PC and are further derived to obtain a series of PTT for estimating beat-by-beat BP using Chen's method. We had 9 healthy subjects undergo the BP monitoring experiments of still sitting on a chair for 3 minutes, lying on a bed for 10 minutes, and pedaling using ergometer for 11 minutes in order to assess the accuracy of the estimated BP. A Finometer and a cuff-type BP meter were used as references in the experiments. Preliminary results showed that the mean error and mean absolute difference (MAD) of estimated BP were within -0.5 ± 5.3 mmHg and 4.1 ± 3.4 mmHg, respectively, compared to references. The result suggests that the proposed BP estimation system has the potential for long-term home BP monitoring.
authors.forename: Zunyi
authors.initials: Z
authors.lastname: Tang
authors.forename: Masaki
authors.initials: M
authors.lastname: Sekine
authors.forename: Toshiyo
authors.initials: T
authors.lastname: Tamura
authors.forename: Masaki
authors.initials: M
authors.lastname: Yoshida
authors.forename: Wenxi
authors.initials: W
authors.lastname: Chen
mesh_terms: D001794:Blood Pressure; D018660:Blood Pressure Monitoring, Ambulatory / Q000379:methods*; D004562:Electrocardiography / Q000379:methods; D006801:Humans; D006973:Hypertension / Q000175:diagnosis; D008297:Male; D017156:Photoplethysmography / Q000379:methods; D063177:Pulse Wave Analysis / Q000379:methods*; D055815:Young Adult