title: Automated analysis of myocardial deformation at dobutamine stress echocardiography: an angiographic validation.
abstract: OBJECTIVE
  We investigated the accuracy of automated analysis of myocardial deformation during dobutamine stress echocardiography (DSE).
  
  
  BACKGROUND
  The time required for segmental measurement of strain rate imaging (SRI) limits its feasibility for quantification of DSE.
  
  
  METHODS
  Myocardial deformation was assessed at DSE in 197 patients, 76 with and 61 without coronary artery disease (CAD) at angiography, and 60 at low risk of CAD. Automated deformation analysis was based on velocity gradient and segment length methods of measuring longitudinal motion within a region of interest tracked through the cardiac cycle. Results were compared with independent wall motion scoring (WMS). Patients were randomly divided; group A (n = 69) established optimal cutoffs for the parameters and group B (n = 68) tested their accuracy.
  
  
  RESULTS
  The feasibility of WMS exceeded that of both SRI methods at rest and at peak stress. In group A, the area under the receiver-operating characteristics curve of the peak systolic strain rate was 0.90 by both methods, and the optimal cutoffs for detection of CAD were -1.3 (velocity gradient) and -1.2 s(-1) (segment length). The areas under the receiver-operating characteristics curves for end-systolic strain were less (0.87) by both methods, with respective cutoffs of 9% and 8%. In group B, the velocity and segment length methods had respective sensitivities of 87% and 84% for SR, and 87% and 88% for end-systolic strain. Both significantly exceeded that of WMS in the same group (75%).
  
  
  CONCLUSIONS
  Automated analysis of myocardial deformation at DSE is feasible and accurate, and may increase the sensitivity of expert conventional reading.
authors: Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway; University of Queensland, Brisbane, Australia.
authors: Charlotte
authors: C
authors: Bjork Ingul
authors: Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway.
authors: Asbjorn
authors: A
authors: Stoylen
authors: Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway.
authors: Stig A
authors: SA
authors: Slordahl
authors: Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway.
authors: Rune
authors: R
authors: Wiseth
authors: University of Queensland, Brisbane, Australia.
authors: Malcolm
authors: M
authors: Burgess
authors: University of Queensland, Brisbane, Australia.. Electronic address: tmarwick@uq.edu.au.
authors: Thomas H
authors: TH
authors: Marwick
mesh_terms: D000368:Aged; D001331:Automation; D017023:Coronary Angiography / Q000379:methods*; D025401:Echocardiography, Stress / Q000379:methods*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging*; D015588:Observer Variation; D011336:Probability; D012372:ROC Curve; D018570:Risk Assessment; D012494:Sampling Studies; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index