title: The change in arterial stiffness over the cardiac cycle rather than diastolic stiffness is independently associated with left ventricular mass index in healthy middle-aged individuals.
abstract: BACKGROUND
  The current standard for arterial stiffness assessment, aortic pulse wave velocity (aPWV), is measured at diastolic pressure. Arterial stiffness, however, is pressure dependent. At the carotid artery level, the degree of this dependency can be quantified as the difference (ΔPWV) between systolic and diastolic (cPWVd) carotid pulse wave velocity. Biomechanically, a greater ΔPWV implies greater increases in left ventricular afterload with physical activity. Therefore, we hypothesized, that ΔPWV is more strongly associated with left ventricular mass index (LVMI) than aPWV and cPWVd.
  
  
  METHODS
  In 1776 healthy individuals from the Asklepios cohort (age 35-55 years), ΔPWV was obtained from combined carotid artery ultrasound and tonometry recordings. Multiple linear regression analysis was performed to investigate the associations of ΔPWV, cPWVd and aPWV with LVMI, adjusting for age, sex, mean blood pressure (MBP), central pulse pressure, and other possible confounders.
  
  
  RESULTS
  ΔPWV was 2.4 ± 1.2 m/s (mean ± SD), ranging from 0.8 m/s, indicating almost constant arterial stiffness over the cardiac cycle, to 4.4 m/s, reflecting substantial pressure dependency. ΔPWV was significantly associated with LVMI (β of 2.46 g/m per m/s, P < 0.001), even after full adjustment (β of 0.56 g/m per m/s, P = 0.03). cPWVd and aPWV had clear crude associations with LVMI (P < 0.001), but lost significance after adjustment (β of -0.48 and -0.33 g/m per m/s, with P = 0.11 and 0.2, respectively).
  
  
  CONCLUSIONS
  The change in arterial stiffness over the cardiac cycle, rather than diastolic stiffness, is independently associated with LVMI in healthy middle-aged individuals. Therefore, the pressure dependency of arterial stiffness should be considered in cardiovascular risk assessment.
authors.affiliation: Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University Medical Centre, Maastricht, The Netherlands.
authors.forename: Evelien
authors.initials: E
authors.lastname: Hermeling
authors.forename: Sebastian J
authors.initials: SJ
authors.lastname: Vermeersch
authors.forename: Ernst R
authors.initials: ER
authors.lastname: Rietzschel
authors.forename: Marc L
authors.initials: ML
authors.lastname: de Buyzere
authors.forename: Thierry C
authors.initials: TC
authors.lastname: Gillebert
authors.forename: Roel J
authors.initials: RJ
authors.lastname: van de Laar
authors.forename: Isabel
authors.initials: I
authors.lastname: Ferreira
authors.forename: Arnold P
authors.initials: AP
authors.lastname: Hoeks
authors.forename: Luc M
authors.initials: LM
authors.lastname: van Bortel
authors.forename: Robert S
authors.initials: RS
authors.lastname: Reneman
authors.forename: Patrick
authors.initials: P
authors.lastname: Segers
authors.forename: Koen D
authors.initials: KD
authors.lastname: Reesink
mesh_terms: D000328:Adult; D001158:Arteries / Q000502:physiology*; D015331:Cohort Studies; D003187:Compliance; D006352:Heart Ventricles / Q000033:anatomy & histology*; D006801:Humans; D008875:Middle Aged; D009929:Organ Size; D012016:Reference Values