title: Assessment of Model Based (Input) Impedance, Pulse Wave Velocity, and Wave Reflection in the Asklepios Cohort.
abstract: OBJECTIVE
  Arterial stiffness and wave reflection parameters assessed from both invasive and non-invasive pressure and flow readings are used as surrogates for ventricular and vascular load. They have been reported to predict adverse cardiovascular events, but clinical assessment is laborious and may limit widespread use. This study aims to investigate measures of arterial stiffness and central hemodynamics provided by arterial tonometry alone and in combination with aortic root flows derived by echocardiography against surrogates derived by a mathematical pressure and flow model in a healthy middle-aged cohort.
  
  
  METHODS
  Measurements of carotid artery tonometry and echocardiography were performed on 2226 ASKLEPIOS study participants and parameters of systemic hemodynamics, arterial stiffness and wave reflection based on pressure and flow were measured. In a second step, the analysis was repeated but echocardiography derived flows were substituted by flows provided by a novel mathematical model. This was followed by a quantitative method comparison.
  
  
  RESULTS
  All investigated parameters showed a significant association between the methods. Overall agreement was acceptable for all parameters (mean differences: -0.0102 (0.033 SD) mmHg*s/ml for characteristic impedance, 0.36 (4.21 SD) mmHg for forward pressure amplitude, 2.26 (3.51 SD) mmHg for backward pressure amplitude and 0.717 (1.25 SD) m/s for pulse wave velocity).
  
  
  CONCLUSIONS
  The results indicate that the use of model-based surrogates in a healthy middle aged cohort is feasible and deserves further attention.
authors.affiliation: Health & Environment Department, AIT Austrian Institute of Technology, Vienna, Austria.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Hametner
authors.affiliation: Health & Environment Department, AIT Austrian Institute of Technology, Vienna, Austria; Department of Analysis & Scientific Computing, Vienna University of Technology, Vienna, Austria.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Parragh
authors.affiliation: Health & Environment Department, AIT Austrian Institute of Technology, Vienna, Austria.
authors.forename: Christopher
authors.initials: C
authors.lastname: Mayer
authors.affiliation: Cardiology Department, Klinikum Wels-Grieskirchen, Wels, Austria.
authors.forename: Thomas
authors.initials: T
authors.lastname: Weber
authors.affiliation: Department of Pharmacology, Ghent University, Ghent, Belgium.
authors.forename: Luc
authors.initials: L
authors.lastname: Van Bortel
authors.affiliation: Department of Pharmacology, Ghent University, Ghent, Belgium.
authors.forename: Marc
authors.initials: M
authors.lastname: De Buyzere
authors.affiliation: Institute of Biomedical Technology, iMinds Medical IT, Ghent University, Ghent, Belgium.
authors.forename: Patrick
authors.initials: P
authors.lastname: Segers
authors.affiliation: Department of Internal Medicine, Ghent University, Ghent, Belgium.
authors.forename: Ernst
authors.initials: E
authors.lastname: Rietzschel
authors.affiliation: Health & Environment Department, AIT Austrian Institute of Technology, Vienna, Austria; Department of Analysis & Scientific Computing, Vienna University of Technology, Vienna, Austria.
authors.forename: Siegfried
authors.initials: S
authors.lastname: Wassertheurer
mesh_terms: D000328:Adult; D002339:Carotid Arteries / Q000502:physiology* / Q000503:physiopathology*; D015331:Cohort Studies; D004452:Echocardiography; D017097:Electric Impedance; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008365:Manometry; D008875:Middle Aged; D008954:Models, Biological; D063177:Pulse Wave Analysis; D059289:Vascular Stiffness