title: Evaluation of different magnetic resonance imaging techniques for the assessment of active left atrial emptying.
abstract: OBJECTIVE
  There is currently no agreement on the best method of assessing active left atrial (LA) emptying. This study evaluated the relative merits of cine- and velocity encoded (VENC) magnetic resonance imaging (MRI) for the assessment of active LA emptying.
  
  
  METHODS
  Total LA emptying volume (TLAEV) and active LA stroke volume (ALASV) were assessed in 107 consecutive patients using cine-MRI and transmitral flow measurements by VENC-MRI. The fraction of active LA emptying (ALAEF) was calculated as the ratio of ALASV to TLAEV. LA and left ventricular (LV) output were calculated by multiplying TLAEV and LV stroke volume by heart rate, respectively.
  
  
  RESULTS
  Intra- and inter-observer variances were significantly larger for cine-MRI than for VENC-MRI measurements of ALASV (24.7 mL(2) vs. 3.7 mL(2) and 57.7 mL(2) vs. 4.2 mL(2); P < 0.0001). Biplane cine-MRI underestimated TLAEV (mean difference -57 ± 32 %; P < 0.0001) and ALASV (mean difference -24 ± 51 %; P < 0.0001) but overestimated ALAEF (mean difference 31 ± 54 %, P < 0.0001) compared with VENC-MRI. There was significantly better agreement between LV output and LA output measured by VENC-MRI compared with LA output measured by cine-MRI (mean difference 0.30 ± 1.12 L/min vs. -2.05 ± 1.44 L/min; P < 0.0001).
  
  
  CONCLUSIONS
  VENC-MRI is the more appropriate method of assessing active LA emptying and its use should be favoured.
authors.affiliation: Department of Cardiology, Electrophysiology, Center for Cardiology and Cardiovascular Surgery, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany. ka.muellerleile@uke.de
authors.forename: Kai
authors.initials: K
authors.lastname: Muellerleile
authors.forename: Michael
authors.initials: M
authors.lastname: Groth
authors.forename: Dennis
authors.initials: D
authors.lastname: Saring
authors.forename: Daniel
authors.initials: D
authors.lastname: Steven
authors.forename: Arian
authors.initials: A
authors.lastname: Sultan
authors.forename: Imke
authors.initials: I
authors.lastname: Drewitz
authors.forename: Boris
authors.initials: B
authors.lastname: Hoffmann
authors.forename: Jakob
authors.initials: J
authors.lastname: Lueker
authors.forename: Gerhard
authors.initials: G
authors.lastname: Adam
authors.forename: Gunnar K
authors.initials: GK
authors.lastname: Lund
authors.forename: Stephan
authors.initials: S
authors.lastname: Willems
authors.forename: Thomas
authors.initials: T
authors.lastname: Rostock
mesh_terms: D000368:Aged; D000465:Algorithms; D016279:Atrial Function, Left; D005260:Female; D006325:Heart Atria / Q000473:pathology* / Q000503:physiopathology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity