title: Measuring age-dependent myocardial stiffness across the cardiac cycle using MR elastography: A reproducibility study.
abstract: OBJECTIVE
  To assess reproducibility in measuring left ventricular (LV) myocardial stiffness in volunteers throughout the cardiac cycle using MR elastography (MRE) and to determine its correlation with age.
  
  
  METHODS
  Cardiac MRE (CMRE) was performed on 29 normal volunteers, with ages ranging from 21 to 73 years. For assessing reproducibility of CMRE-derived stiffness measurements, scans were repeated per volunteer. Wave images were acquired throughout the LV myocardium, and were analyzed to obtain mean stiffness during the cardiac cycle. CMRE-derived stiffness values were correlated to age.
  
  
  RESULTS
  Concordance correlation coefficient revealed good interscan agreement with rc of 0.77, with P-value < 0.0001. Significantly higher myocardial stiffness was observed during end-systole (ES) compared with end-diastole (ED) across all subjects. Additionally, increased deviation between ES and ED stiffness was observed with increased age.
  
  
  CONCLUSIONS
  CMRE-derived stiffness is reproducible, with myocardial stiffness changing cyclically across the cardiac cycle. Stiffness is significantly higher during ES compared with ED. With age, ES myocardial stiffness increases more than ED, giving rise to an increased deviation between the two.
authors.affiliation: Department of Radiology, The Ohio State University College of Medicine, Columbus, Ohio, USA.
authors.forename: Peter A
authors.initials: PA
authors.lastname: Wassenaar
authors.affiliation: Department of Radiology, The Ohio State University College of Medicine, Columbus, Ohio, USA.|Department of Biomedical Engineering, The Ohio State University, Columbus, Ohio, USA.
authors.forename: Chethanya N
authors.initials: CN
authors.lastname: Eleswarpu
authors.affiliation: Department of Radiology, The Ohio State University College of Medicine, Columbus, Ohio, USA.|Department of Mechanical Engineering, The Ohio State University, Columbus, Ohio, USA.
authors.forename: Samuel A
authors.initials: SA
authors.lastname: Schroeder
authors.affiliation: Center for Biostatistics, The Ohio State University, Columbus, Ohio, USA.
authors.forename: Xiaokui
authors.initials: X
authors.lastname: Mo
authors.affiliation: Department of Radiology, The Ohio State University College of Medicine, Columbus, Ohio, USA.
authors.forename: Brian D
authors.initials: BD
authors.lastname: Raterman
authors.affiliation: Department of Radiology, The Ohio State University College of Medicine, Columbus, Ohio, USA.|Department of Internal Medicine-Division of Cardiovascular Medicine, The Ohio State University College of Medicine, Columbus, Ohio, USA.
authors.forename: Richard D
authors.initials: RD
authors.lastname: White
authors.affiliation: Department of Radiology, The Ohio State University College of Medicine, Columbus, Ohio, USA.|Department of Biomedical Engineering, The Ohio State University, Columbus, Ohio, USA.|Department of Internal Medicine-Division of Cardiovascular Medicine, The Ohio State University College of Medicine, Columbus, Ohio, USA.
authors.forename: Arunark
authors.initials: A
authors.lastname: Kolipaka
mesh_terms: D000328:Adult; D000368:Aged; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D059289:Vascular Stiffness / Q000502:physiology*; D055815:Young Adult
keywords: MR elastography; MRE; cardiac MRE; magnetic resonance elastography; myocardial stiffness