title: Age-associated changes in regional aortic pulse wave velocity.
abstract: OBJECTIVE
  This study was designed to determine noninvasively the age-associated changes in regional mechanical properties in normals using phase-contrast magnetic resonance imaging (PCMRI).
  
  
  BACKGROUND
  It has been well documented that there is a progressive increase in aortic pulse wave velocity (PWV) with age. Previously, PWV has been measured at a single aortic location, or has compared arterial waves between carotid and femoral points to determine PWV.
  
  
  METHODS
  Applanation tonometry (TONO) and in-plane PCMR was performed in 24 volunteers (12 men) ranging in age from 21 to 72 years old. The PCMRI PWV was measured in three aortic segments. As validation, TONO was performed to determine PWV between the carotid and femoral artery.
  
  
  RESULTS
  When PCMRI PWV was averaged over the three locations, it was not different from TONO (7.9 +/- 2.3 vs. 7.6 +/- 2.4 m/s, respectively). When the volunteers were divided into groups of < 55 and > or =55 years old, the younger group showed similar PWV at each aortic location. However, the older group displayed significantly increased PWV in the region spanning the ascending and proximal descending aorta compared with the mid-thoracic or abdominal segments (10.6 +/- 2.5 m/s, 9.2 +/- 2.8 m/s, and 7.1 +/- 1.7 m/s, respectively, p < 0.001, analysis of variance).
  
  
  CONCLUSIONS
  In-plane PCMRI permits determination of PWV in multiple aortic locations in a single acquisition. Progressive fragmentation of elastic fibers and alterations in the regulation of vascular tone may result in an age-related, regional increase in PWV primarily affecting the proximal aorta.
authors.affiliation: Department of Medicine, Allegheny General Hospital, Pittsburgh, Pennsylvania 15212, USA. wrogers@wpahs.org
authors.forename: W J
authors.initials: WJ
authors.lastname: Rogers
authors.forename: Y L
authors.initials: YL
authors.lastname: Hu
authors.forename: D
authors.initials: D
authors.lastname: Coast
authors.forename: D A
authors.initials: DA
authors.lastname: Vido
authors.forename: C M
authors.initials: CM
authors.lastname: Kramer
authors.forename: R E
authors.initials: RE
authors.lastname: Pyeritz
authors.forename: N
authors.initials: N
authors.lastname: Reichek
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D001011:Aorta / Q000502:physiology*; D001783:Blood Flow Velocity / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D014159:Transducers