title: Site-specific coupling between vascular wall thickness and function: an observational MRI study of vessel wall thickening and stiffening in hypertension.
abstract: OBJECTIVE
  The objective of this study was to evaluate associations between aortic pulse wave velocity (PWV) and aortic and carotid vessel wall thickness (VWT) using cardiovascular magnetic resonance imaging (MRI) in patients with hypertension as compared with healthy adult volunteers.
  
  
  METHODS
  Local medical ethics approval was obtained and the participants gave informed consent. Fifteen patients with hypertension (5 men and 10 women; mean [SD] age, 49 [14] years) and 15 age- and sex-matched healthy volunteers were prospectively included and compared. All participants underwent MRI examination for measuring aortic and carotid VWT and aortic PWV with well-validated MRI techniques at 1.5- and 3-T MRI systems: PWV was assessed from velocity-encoded MRI and VWT was assessed by using dual-inversion black-blood gradient-echo imaging techniques. Paired t tests were used for testing differences between the volunteers and the patients and Pearson correlation (r) and univariable and multivariable stepwise linear regression analyses were used to test associations between aortic and carotid arterial wall thickness and stiffness.
  
  
  RESULTS
  Mean values for aortic PWV and aortic and carotid VWT (indexed for body surface area [BSA]) were all significantly higher in patients with hypertension as compared with the healthy volunteers (ie, aortic PWV, 7.0 ± 1.4 m/s vs 5.7 ± 1.3 m/s; aortic VWT/BSA, 0.12 ± 0.03 mL/m vs 0.10 ± 0.03 mL/m; carotid VWT/BSA, 0.04 ± 0.01 mL/m vs 0.03 ± 0.01 mL/m; all P < 0.01). Aortic PWV was highly correlated with aortic VWT/BSA (r = 0.76 and P = 0.002 in the patients vs r = 0.63 and P = 0.02 in the volunteers), and in the patients, aortic PWV was moderately correlated with carotid VWT/BSA (r = 0.50; P = 0.04). In the volunteers, correlation between aortic PWV and carotid VWT/BSA was not significant (r = 0.40; P = 0.13). In addition, aortic VWT/BSA was significantly correlated with carotid VWT/BSA, in both the patients (r = 0.60; P = 0.005) and volunteers (r = 0.57; P = 0.007).
  
  
  CONCLUSIONS
  In the patients with hypertension and the healthy volunteers, the aortic PWV is associated more strongly with aortic wall thickness than with carotid wall thickness, reflecting site-specific coupling between vascular wall thickness and function.
authors.affiliation: Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands. a.brandts@lumc.nl
authors.forename: Anne
authors.initials: A
authors.lastname: Brandts
authors.forename: Jos J M
authors.initials: JJ
authors.lastname: Westenberg
authors.forename: Saskia G C
authors.initials: SG
authors.lastname: van Elderen
authors.forename: Lucia J M
authors.initials: LJ
authors.lastname: Kroft
authors.forename: Stijntje D
authors.initials: SD
authors.lastname: Roes
authors.forename: Jouke T
authors.initials: JT
authors.lastname: Tamsma
authors.forename: Rob J
authors.initials: RJ
authors.lastname: van der Geest
authors.forename: Hildo J
authors.initials: HJ
authors.lastname: Lamb
authors.forename: Joost
authors.initials: J
authors.lastname: Doornbos
authors.forename: Hein
authors.initials: H
authors.lastname: Putter
authors.forename: Matthias
authors.initials: M
authors.lastname: Stuber
authors.forename: Albert
authors.initials: A
authors.lastname: de Roos
mesh_terms: D000328:Adult; D000368:Aged; D001783:Blood Flow Velocity; D001808:Blood Vessels / Q000473:pathology* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000473:pathology* / Q000503:physiopathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D059289:Vascular Stiffness; D055815:Young Adult