title: Comparison of real-time three-dimensional echocardiography with cardiovascular magnetic resonance for left ventricular volumetric assessment in unselected patients.
abstract: OBJECTIVE
  To compare left ventricular (LV) volume indices and the ejection fraction (EF) obtained using real-time three-dimensional echocardiography (RT3DE) and cardiovascular magnetic resonance (CMR) in unselected patients representative of 'real-world' clinical practice, and to determine the effect of RT3DE image quality on these parameters.
  
  
  RESULTS
  Sixty consecutive patients undergoing CMR underwent same day RT3DE. LV volume and EF measurements were made using both modalities and compared. All scans were independently analysed by a second observer to assess inter-observer variability, and 40% were re-analysed to assess intra-observer variability. RT3DE image quality was graded as good, adequate, and non-analysable. Thirteen (22%) patients had good RT3DE image quality, 29 (48%) had adequate image quality, and 18 (30%) had image quality precluding analysis. Body mass index and arrhythmia frequency were higher in patients with suboptimal image quality. RT3DE significantly underestimated end-diastolic volume (EDV) (-45 ± 35 mL, P < 0.001), end-systolic volume (ESV) (-11 ± 24 mL, P = 0.004), and EF (-7 ± 9%, P < 0.001) compared with CMR although the degree of underestimation was substantially less when image quality was good. Eleven patients (18%) classified as having a normal EF by CMR had a reduced EF according to RT3DE, all but one of which had suboptimal image quality. Observer variability for RT3DE was higher than for CMR for all parameters, however, the difference was not significant when RT3DE image quality was good.
  
  
  CONCLUSIONS
  In contrast to previously published data from highly selected patient groups, 'real-world' RT3DE substantially underestimates LV volumes and EF. The degree of underestimation is related to image quality.
authors: Division of Cardiology and Cardiothoracic Surgery, University Hospital of South Manchester, Southmoor Road, Wythenshawe, Manchester M23 9LT, UK. chrismiller@doctors.org.uk
authors: Christopher A
authors: CA
authors: Miller
authors: Keith
authors: K
authors: Pearce
authors: Peter
authors: P
authors: Jordan
authors: Rachel
authors: R
authors: Argyle
authors: David
authors: D
authors: Clark
authors: Martin
authors: M
authors: Stout
authors: Simon G
authors: SG
authors: Ray
authors: Matthias
authors: M
authors: Schmitt
mesh_terms: D000368:Aged; D019560:Echocardiography, Three-Dimensional / Q000379:methods; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D013318:Stroke Volume; D013997:Time Factors