title: Mitral annulus motion versus long-axis fractional shortening.
abstract: BACKGROUND
  In most echocardiographic studies concerning mitral annulus motion (MAM) in the assessment of left ventricular (LV) systolic function, comparisons have been performed between MAM, which represents a distance, and ejection fraction (EF), which represents a ratio between volumes. However, in theory, it is probably more suitable to compare the long-axis fractional shortening (FS(L)) (the ratio between the change in length [ie, MAM] and the end-diastolic length of the left ventricle) with EF.
  
  
  OBJECTIVE
  To compare EF with MAM and EF with FS(L) in the assessment of LV systolic function.
  
  
  METHODS
  Thirty healthy subjects were investigated using echo-cardiography, and the linear correlations between EF and MAM, and EF and FS(L) were calculated.
  
  
  RESULTS
  The linear correlation (r) was found to be higher between EF and FS(L) (r=0.65; P<0.001) than between EF and MAM (r=0.49; P<0.01).
  
  
  CONCLUSIONS
  The higher correlation between EF and FS(L) than between EF and MAM suggests that FS(L), which includes a correction for ventricular length, may be a more suitable index of LV systolic function than MAM per se.
authors.affiliation: Department of Clinical Physiology, Karlskoga Hospital, Karlskoga.
authors.forename: Kent
authors.initials: K
authors.lastname: Emilsson
authors.forename: Rigmor
authors.initials: R
authors.lastname: Egerlid
authors.forename: Britt-Marie
authors.initials: BM
authors.lastname: Nygren
authors.forename: Birger
authors.initials: B
authors.lastname: Wandt