title: Validation of a new non-invasive portable tonometer for determining arterial pressure wave and pulse wave velocity: the PulsePen device.
abstract: OBJECTIVE
  To validate a new, small portable tonometer (PulsePen) that is able to assess carotid artery pressure and to measure pulse wave velocity (PWV) non-invasively. Its software provides absolute arterial pressure values, an assessment of arterial pulse wave contours, an estimation of reflection waves and measurements of PWV.
  
  
  METHODS
  Two validation studies were carried out. The aim of the first study was to compare arterial pressure values and pulse wave contours recorded in the carotid artery using the PulsePen versus intra-arterial simultaneous measurements in 10 patients undergoing cardiac catheterization. The pulse wave contour was assessed using Fourier analysis. The comparison between the two methods showed no difference in arterial pressure wave spectral moduli from harmonics 1 to 6. The second study compared PWV measurements taken with the PulsePen (one tonometer) and measurements performed with two Millar tonometers in 68 subjects (32 men, 36 women). PulsePen measurements were realized as two consecutive measurements in the carotid and femoral arteries, both synchronized by electrocardiogram. The pulse wave transit time was calculated as the difference between the time delay of the femoral pulse wave and the carotid pulse wave in relation to the R wave of the electrocardiogram. These measurements were compared with PWV obtained by simultaneous carotid and femoral measurements with the two Millar tonometers. No difference between the two methods was found, with a variation coefficient of 7.7%. The variation coefficients of the inter-observer and intra-observer reproducibility for the PulsePen were 7.9 and 7.2%, respectively.
  
  
  CONCLUSIONS
  These results show that the PulsePen enables an easy and reliable evaluation of central arterial pressure and stiffness in clinical ambulatory practice, especially in high-risk patients in whom arterial stiffness has been shown to be a significant indicator of morbidity and mortality.
authors.affiliation: Department of Internal Medicine, Bufalini Hospital, Cesena, Italy. psalvi.md@libero.it
authors.forename: Paolo
authors.initials: P
authors.lastname: Salvi
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Lio
authors.forename: Carlos
authors.initials: C
authors.lastname: Labat
authors.forename: Enrico
authors.initials: E
authors.lastname: Ricci
authors.forename: Bruno
authors.initials: B
authors.lastname: Pannier
authors.forename: Athanase
authors.initials: A
authors.lastname: Benetos
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001783:Blood Flow Velocity; D001794:Blood Pressure; D001795:Blood Pressure Determination / Q000295:instrumentation*; D006328:Cardiac Catheterization; D002339:Carotid Arteries / Q000503:physiopathology; D004548:Elasticity; D004562:Electrocardiography; D004867:Equipment Design; D005260:Female; D005263:Femoral Artery / Q000503:physiopathology; D006801:Humans; D008297:Male; D008365:Manometry / Q000295:instrumentation* / Q000592:standards*; D008875:Middle Aged; D011674:Pulse; D015203:Reproducibility of Results; D012984:Software