title: In vivo evaluation of a novel, wrist-mounted arterial pressure sensing device versus the traditional hand-held tonometer.
abstract: Although hemodynamic parameters can be assessed non-invasively, state-of-the-art non-invasive systems generally require an expert operator and are not applicable for ambulatory measurements. These limitations have restricted our understanding of the continuous behavior of hemodynamic parameters. In this manuscript, we introduce a novel wrist-mounted device that incorporates an array of pressure sensors which can be used to extract arterial waveforms and relevant pulse wave analysis biomarkers. In vivo evaluation is performed with Bland-Altman analysis to compare the novel sensor to a gold-standard hand-held tonometer by assessing their reproducibility and agreement in peripheral augmentation index (AIx) estimation at the radial artery. Arterial waves from 28 randomly selected participants were recorded in a controlled environment. Initially we assess the reproducibility of AIx results for both devices. The intra-class correlation coefficient (ICC) and mean difference ± SD were [0.913, 0.033±0.048] and [0.859, 0.039±0.076] for the hand-held and the wrist-mounted tonometer respectively. We then show that the AIx values derived from the novel tonometer have good agreement, accuracy, and precision when compared against the AIx values derived from the reference hand-held tonometer (ICC 0.927, mean difference 0.026±0.049). In conclusion, we have presented evidence that the new wrist-mounted arterial pressure sensor records arterial waveforms that can be processed to yield AIx values that are in good agreement with its traditional hand-held counterpart.
authors.affiliation: Microsoft Research, Redmond, WA USA; Laboratory of Hemodynamics and Cardiovascular Technology, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland. Electronic address: orestis@hotmail.ch.
authors.forename: Orestis
authors.initials: O
authors.lastname: Vardoulis
authors.affiliation: Microsoft Research, Redmond, WA USA.
authors.forename: T Scott
authors.initials: TS
authors.lastname: Saponas
authors.affiliation: Microsoft Research, Redmond, WA USA. Electronic address: dan@microsoft.com.
authors.forename: Dan
authors.initials: D
authors.lastname: Morris
authors.affiliation: Microsoft Research, Redmond, WA USA.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Villar
authors.affiliation: Microsoft Research, Redmond, WA USA.
authors.forename: Greg
authors.initials: G
authors.lastname: Smith
authors.affiliation: Microsoft Research, Redmond, WA USA; University of Washington, Seattle, WA USA.
authors.forename: Shwetak
authors.initials: S
authors.lastname: Patel
authors.affiliation: Microsoft Research, Redmond, WA USA.
authors.forename: Desney
authors.initials: D
authors.lastname: Tan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D062186:Arterial Pressure; D001795:Blood Pressure Determination / Q000295:instrumentation*; D006225:Hand; D006801:Humans; D008297:Male; D008365:Manometry / Q000295:instrumentation*; D008875:Middle Aged; D014953:Wrist; D055815:Young Adult
keywords: Arterial stiffness; Arterial tonometry; Pressure sensor; Radial artery