title: Relations Between Aortic Stiffness and Left Ventricular Mechanical Function in the Community.
abstract: Aortic stiffness impairs optimal ventricular-vascular coupling and left ventricular systolic function, particularly in the long axis. Left ventricular global longitudinal strain (GLS) has recently emerged as a sensitive measure of early cardiac dysfunction. In this study, we investigated the relation between aortic stiffness and GLS in a large community-based sample.
  
  
  
  In 2495 participants (age 39-90 years, 57% women) of the Framingham Offspring and Omni cohorts, free of cardiovascular disease, we performed tonometry to measure arterial hemodynamics and echocardiography to assess cardiac function. Aortic stiffness was evaluated as carotid-femoral pulse wave velocity and as characteristic impedance, and GLS was calculated using speckle tracking-based measurements. In multivariable analyses adjusting for age, sex, height, systolic blood pressure, augmentation index, left ventricular structure, and additional cardiovascular risk factors, increased carotid-femoral pulse wave velocity (B±SE: 0.122±0.030% strain per SD, P<0.0001) and characteristic impedance (0.090±0.029, P=0.002) were both associated with worse GLS. We observed effect modification by sex on the relation between characteristic impedance and GLS (P=0.004); in sex-stratified multivariable analyses, the relation between greater characteristic impedance and worse GLS persisted in women (0.145±0.039, P=0.0003) but not in men (P=0.73).
  
  
  
  Multiple measures of increased aortic stiffness were cross-sectionally associated with worse GLS after adjusting for hemodynamic variables. Parallel reductions in left ventricular long axis shortening and proximal aortic longitudinal strain in individuals with a stiffened proximal aorta, from direct mechanical ventricular-vascular coupling, offers an alternative explanation for the observed relations.
authors.affiliation: Cardiovascular Engineering, Inc., Norwood, MA.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Bell
authors.affiliation: Department of Biostatistics, Boston University School of Public Health, Boston, MA.
authors.forename: Elizabeth L
authors.initials: EL
authors.lastname: McCabe
authors.affiliation: Department of Biostatistics, Boston University School of Public Health, Boston, MA.|Framingham Heart Study, Framingham, MA.
authors.forename: Martin G
authors.initials: MG
authors.lastname: Larson
authors.affiliation: Framingham Heart Study, Framingham, MA.
authors.forename: Jian
authors.initials: J
authors.lastname: Rong
authors.affiliation: Division of Cardiovascular Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, MA.
authors.forename: Allison A
authors.initials: AA
authors.lastname: Merz
authors.affiliation: Framingham Heart Study, Framingham, MA.
authors.forename: Ewa
authors.initials: E
authors.lastname: Osypiuk
authors.affiliation: Framingham Heart Study, Framingham, MA.
authors.forename: Birgitta T
authors.initials: BT
authors.lastname: Lehman
authors.affiliation: Framingham Heart Study, Framingham, MA.
authors.forename: Plamen
authors.initials: P
authors.lastname: Stantchev
authors.affiliation: Veterans Administration Hospital, West Roxbury, MA.
authors.forename: Jayashri
authors.initials: J
authors.lastname: Aragam
authors.affiliation: Department of Epidemiology, Boston University School of Public Health, Boston, MA.|Framingham Heart Study, Framingham, MA.|Preventive Medicine and Cardiology Sections, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA.
authors.forename: Emelia J
authors.initials: EJ
authors.lastname: Benjamin
authors.affiliation: Preventive Medicine and Cardiology Sections, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA.|Evans Department of Medicine, Boston University School of Medicine, Boston, MA.
authors.forename: Naomi M
authors.initials: NM
authors.lastname: Hamburg
authors.affiliation: Department of Epidemiology, Boston University School of Public Health, Boston, MA.|Framingham Heart Study, Framingham, MA.|Preventive Medicine and Cardiology Sections, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA.
authors.forename: Ramachandran S
authors.initials: RS
authors.lastname: Vasan
authors.affiliation: Cardiovascular Engineering, Inc., Norwood, MA garyfmitchell@mindspring.com scheng@rics.bwh.harvard.edu.
authors.forename: Gary F
authors.initials: GF
authors.lastname: Mitchell
authors.affiliation: Framingham Heart Study, Framingham, MA garyfmitchell@mindspring.com scheng@rics.bwh.harvard.edu.|Division of Cardiovascular Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, MA.
authors.forename: Susan
authors.initials: S
authors.lastname: Cheng
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002318:Cardiovascular Diseases / Q000453:epidemiology; D004452:Echocardiography; D017097:Electric Impedance; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008365:Manometry; D008875:Middle Aged; D015999:Multivariate Analysis; D063177:Pulse Wave Analysis; D012307:Risk Factors; D059289:Vascular Stiffness / Q000502:physiology*; D016277:Ventricular Function, Left / Q000502:physiology*
keywords: aortic stiffness; characteristic impedance; global longitudinal strain; left ventricle function; pulse wave velocity; ventricular/vascular coupling hemodynamics