title: Role of temporal resolution in selection of the appropriate strain technique for evaluation of subclinical myocardial dysfunction.
abstract: OBJECTIVE
  To assess the effects of frame and volume rate on the concordance between two-dimensional speckle tracking strain (2DS) and three-dimensional speckle tracking strain (3DS), and between 2DS and triplane imaging of speckle tracking (Tri-P).
  
  
  METHODS
  Global longitudinal strains (GLSs) derived from 2DS, 3DS, and Tri-P were compared among 142 prospectively recruited patients who underwent evaluation of subclinical left ventricle (LV) function.
  
  
  RESULTS
  Feasibility to obtain GLS of 3DS was significantly higher than that of Tri-P (76% vs. 47%, P < 0.001). The correlation between 2DS and 3DS was only modest (r = 0.47) whereas that of 2DS and Tri-P was better (r = 0.67). The difference in frame/volume rate between two methods also affected their correlation. A volume rate between 34 and 50 volumes/sec had the highest correlation between 2DS and 3DS (r = 0.72). The correlation between 2DS and Tri-P was better with a difference in frame-rate ≤20 per second than with a difference >20 per second. Likewise, there was a better correlation between 2DS and 3DS when the difference between 2D frame rate and 3D volume rate was ≤40 per second, compared to when it was >40 per second. These associations differed from segment to segment and the apical segments had the highest correlation and the basal the lowest.
  
  
  CONCLUSIONS
  The feasibility of each means of strain calculation showed important differences, with 2DS being the most attainable. Strain values were not interchangeable among 2DS, Tri-P, and 3DS. Importantly, poor correlations seemed to be driven by differences in acquisition rate. Currently, 2DS offers the most robust measurement of subclinical myocardial dysfunction.
authors.affiliation: Heart and Vascular Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Negishi
authors.forename: Tomoko
authors.initials: T
authors.lastname: Negishi
authors.forename: Deborah A
authors.initials: DA
authors.lastname: Agler
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Plana
authors.forename: Thomas H
authors.initials: TH
authors.lastname: Marwick
mesh_terms: D000465:Algorithms; D019560:Echocardiography, Three-Dimensional / Q000379:methods*; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging*