title: Relations between carotid artery distensibility and heart rate variability The Cardiovascular Risk in Young Finns Study.
abstract: OBJECTIVE
  Reduction in carotid artery wall elasticity may interfere with baroreceptor function that could lead to low vagal tone. We studied at the population level the relations between carotid-artery-distensibility (Cdist) and vagal modulation of heart rate.
  
  
  RESULTS
  Cdist was assessed with ultrasonic measurements of changes in carotid artery diameter during cardiac-cycle. Vagal tone was estimated with the heart rate variability (HRV) in 1872 healthy 24-39year-old subjects. Cdist was significantly related with all HRV-components (always P<0.0001). After adjustments with sex, age and heart rate, we found statistically significant correlation between Cdist and the high-frequency component (HF, estimate of vagal-tone) of HRV (P<0.05). An inverse association between the number of cardiovascular risk-factors and vagal-tone was seen in subjects with less elastic arteries, but not in subjects with more elastic arteries (P for interaction=0.01).
  
  
  CONCLUSIONS
  These data support the hypothesis that reduction in carotid artery wall elastic properties may lead to low vagal tone. Furthermore, carotid distensibility seemed to modify the relation between risk-factors and HRV. Increased cardiovascular risk associated with low vagal tone may partly be mediated via changes in carotid artery elastic properties.
authors.affiliation: Research Centre of Applied and Preventive Cardiovascular Medicine, University of Turku, Finland. tuomas.koskinen@utu.fi
authors.forename: Tuomas
authors.initials: T
authors.lastname: Koskinen
authors.forename: Markus
authors.initials: M
authors.lastname: Juonala
authors.forename: Mika
authors.initials: M
authors.lastname: Kähönen
authors.forename: Antti
authors.initials: A
authors.lastname: Jula
authors.forename: Tomi
authors.initials: T
authors.lastname: Laitinen
authors.forename: Liisa
authors.initials: L
authors.lastname: Keltikangas-Järvinen
authors.forename: Jorma
authors.initials: J
authors.lastname: Viikari
authors.forename: Ilkka
authors.initials: I
authors.lastname: Välimäki
authors.forename: Olli T
authors.initials: OT
authors.lastname: Raitakari
mesh_terms: D000328:Adult; D002318:Cardiovascular Diseases / Q000503:physiopathology*; D002339:Carotid Arteries / Q000000981:diagnostic imaging* / Q000503:physiopathology; D004548:Elasticity / Q000502:physiology*; D004562:Electrocardiography; D005260:Female; D005387:Finland; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D012307:Risk Factors; D014463:Ultrasonography; D014630:Vagus Nerve / Q000503:physiopathology; D055815:Young Adult