title: A magnetic resonance perspective of the pulse wave transit time by the Arteriograph device and potential for improving aortic length estimation for central pulse wave velocity.
abstract: BACKGROUND
  Simple reproducible methods of measuring arterial stiffness, a powerful index of prognosis, are becoming available.
  
  
  OBJECTIVE
  To compare the pulse wave transit time (TT) and pulse wave velocity (PWV) between MRI and an arm cuff-based oscillometric method, the Arteriograph.
  
  
  METHODS
  MRI phase-contrast data were acquired at the aortic arch and just above the aortic bifurcation in 49 men (age 53±6 years). Supine left-arm Arteriograph measurements were made after MRI using the surface sternal notch to symphysis pubis pathway length.
  
  
  RESULTS
  MRI TT and PWV covered 86% of aortic root-bifurcation length omitting a mean 4.7 cm of proximal ascending aorta. Arteriograph TT (71±9 ms) was 6.6 ms [95% confidence interval (CI) 3.9-9.4] or 10% higher than MRI (64±10 ms). Arteriograph PWV (7.9±1.3 m/s) was 1.33 m/s (95% CI 0.95-1.70) higher than MRI (6.6±1.2 m/s), primarily because the surface aortic length was 70 mm (95% CI 59-81) longer than MRI. Arteriograph-MRI PWV difference decreased to 0.31 m/s (95% CI 0.01-0.61) when Arteriograph PWV was calculated using the MRI aortic path length and to 0.25 m/s (95% CI -0.05 to 0.55) after correcting for the aortic segments omitted in the MRI method. After similar TT corrections for MRI, the Arteriograph-MRI difference in TT reduced to 3.2 ms (95% CI 0.2-6).
  
  
  CONCLUSIONS
  TT estimations by Arteriograph and MRI are close. More accurate length estimation from MRI-derived models improves Arteriograph PWV measurement.
authors: Cardiovascular Research Group, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK.
authors: Mohammad-Reza
authors: MR
authors: Rezai
authors: Brett R
authors: BR
authors: Cowan
authors: Neal
authors: N
authors: Sherratt
authors: Joseph D
authors: JD
authors: Finn
authors: Frederick C W
authors: FC
authors: Wu
authors: J Kennedy
authors: JK
authors: Cruickshank
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000473:pathology; D000886:Anthropometry; D001012:Aorta, Abdominal / Q000473:pathology* / Q000503:physiopathology; D001013:Aorta, Thoracic / Q000473:pathology* / Q000503:physiopathology; D058070:Asymptomatic Diseases; D006339:Heart Rate; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D009991:Oscillometry / Q000295:instrumentation / Q000379:methods*; D011673:Pulsatile Flow; D063177:Pulse Wave Analysis / Q000295:instrumentation* / Q000379:methods; D015203:Reproducibility of Results; D014655:Vascular Resistance