title: Magnetic resonance imaging detects significant sex differences in human myocardial strain.
abstract: BACKGROUND
  The pathophysiology responsible for the significant outcome disparities between men and women with cardiac disease is largely unknown. Further investigation into basic cardiac physiological differences between the sexes is needed. This study utilized magnetic resonance imaging (MRI)-based multiparametric strain analysis to search for sex-based differences in regional myocardial contractile function.
  
  
  METHODS
  End-systolic strain (circumferential, longitudinal, and radial) was interpolated from MRI-based radiofrequency tissue tagging grid point displacements in each of 60 normal adult volunteers (32 females).
  
  
  RESULTS
  The average global left ventricular (LV) strain among normal female volunteers (n = 32) was significantly larger in absolute value (functionally better) than in normal male volunteers (n = 28) in both the circumferential direction (Male/Female = -0.19 ± 0.02 vs. -0.21 ± 0.02; p = 0.025) and longitudinal direction (Male/Female = -0.14 ± 0.03 vs. -0.16 ± 0.02; p = 0.007).
  
  
  CONCLUSIONS
  The finding of significantly larger circumferential and longitudinal LV strain among normal female volunteers suggests that baseline contractile differences between the sexes may contribute to the well-recognized divergence in cardiovascular disease outcomes. Further work is needed in order to determine the pathologic changes that occur in LV strain between women and men with the onset of cardiovascular disease.
authors.affiliation: Department of Surgery, Washington University School of Medicine, 660 S. Euclid Ave, St. Louis, Missouri 63110, USA. lawtonj@wudosis.wustl.edu
authors.forename: Jennifer S
authors.initials: JS
authors.lastname: Lawton
authors.forename: Brian P
authors.initials: BP
authors.lastname: Cupps
authors.forename: Andrew K
authors.initials: AK
authors.lastname: Knutsen
authors.forename: Ningning
authors.initials: N
authors.lastname: Ma
authors.forename: Beckah D
authors.initials: BD
authors.lastname: Brady
authors.forename: Lina M
authors.initials: LM
authors.lastname: Reynolds
authors.forename: Michael K
authors.initials: MK
authors.lastname: Pasque
mesh_terms: D000328:Adult; D002318:Cardiovascular Diseases / Q000175:diagnosis; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009200:Myocardial Contraction; D009206:Myocardium / Q000473:pathology*; D012727:Sex Characteristics; D013599:Systole; D014463:Ultrasonography