title: Confounding effects of heart rate on pulse wave velocity in paced patients with a low degree of atherosclerosis.
abstract: BACKGROUND
  Pulse wave velocity (PWV), an index of arterial wall stiffness, is modulated by blood pressure (BP). Whether heart rate (HR) is also a modulator of PWV is controversial. Recent research involving mainly patients with high aortic PWV have found either no change or a positive correlation between the two. Given that PWV is increasingly being measured in cardiovascular studies, the relationship between HR and PWV should be known in patients with preserved arterial wall elasticity.
  
  
  OBJECTIVE
  The aim of this study was to evaluate the importance of HR as a determinant of the variability in PWV in patients with a low degree of atherosclerosis.
  
  
  METHODS
  Fourteen patients (five female, nine male; aged 68 +/- 8 years) were evaluated post pacemaker implantation due to sick sinus or carotid hypersensitivity syndromes. Carotid-femoral PWV was measured at rest and during atrial pacing at 80, 90 and 100 bpm (paced HR). Arterial femoral blood flow (AFBF) was measured by echodoppler.
  
  
  RESULTS
  PWV increased from 6.2 +/- 1.5 m/s (mean +/- SD) during resting sinus rhythm (HR 62 +/- 8 bpm; mean +/- SD) to 6.8 +/- 1.0, 7.0 +/- 0.9, and 7.6 +/- 1.1 m/s at pacing rates of 80, 90 and 100 bpm, respectively (P < 0.0001). Systolic (SBP) and mean blood pressure (MBP) remained constant at all HR levels, whereas AFBF increased in a linear fashion.
  
  
  CONCLUSIONS
  These results demonstrate that even in patients with a low degree of atherosclerosis, HR is a potential modulator of carotid-femoral PWV.
authors.affiliation: Service d'Hypertension et de Médecine Vasculaire, CHUV, Lausanne, Switzerland. erik.haesler@chuv.hospvd.ch
authors.forename: Erik
authors.initials: E
authors.lastname: Haesler
authors.forename: Xavier
authors.initials: X
authors.lastname: Lyon
authors.forename: Etienne
authors.initials: E
authors.lastname: Pruvot
authors.forename: Lukas
authors.initials: L
authors.lastname: Kappenberger
authors.forename: Daniel
authors.initials: D
authors.lastname: Hayoz
mesh_terms: D000368:Aged; D001011:Aorta / Q000502:physiology; D001161:Arteriosclerosis / Q000503:physiopathology*; D001783:Blood Flow Velocity / Q000502:physiology*; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D007083:Iliac Artery / Q000502:physiology; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial; D011673:Pulsatile Flow / Q000502:physiology*