title: Strain Analysis by Tissue Doppler Imaging: Comparison of Conventional Manual Measurement with a Semiautomated Approach.
abstract: OBJECTIVE
  Myocardial strain and strain rate (SR) can be derived from either tissue Doppler (TDI) information or two-dimensional speckle tracking. As conventional TDI analysis (TDI-manual) is time-consuming with poor reproducibility, we developed a faster semiautomated approach (TDI-ST). We aimed to study the comparability of TDI-ST with TDI-manual, an established method for measuring strain and SR.
  
  
  METHODS
  Forty healthy subjects (mean age 38.3 ± 12.8 years) and 16 patients with FHL-1 cardiomyopathy (CMP) (36.8 ± 14.2 years) were analyzed with TDI-manual and TDI-ST. TDI-ST was performed with commercial software, using speckle tracking for myocardial tracking and TDI information to derive longitudinal strain and SR from high frame rate TDI recordings. Measurements of longitudinal systolic strain (S) and global S (GLS) made with the two methods were compared with Bland-Altman plots and Deming regression. Receiver operating characteristics (ROC) curves were used to compare discrimination between healthy individuals and patients.
  
  
  RESULTS
  Mean S was -20.11 ± 4.85% (healthy) and -16.12 ± 4.44% (CMP) with TDI-ST and -21.15 ± 5.68% (healthy) and -16.27 ± 6.44 (CMP) with TDI-manual. Using all measured segments, the mean bias was 0.78% strain toward less negative S with TDI-ST; the Deming regression slope was 0.7 for S and 0.9 for GLS. Intra- and inter-observer CVs were 5.4% and 7.0%, respectively. ROC curves showed no significant differences between the methods.
  
  
  CONCLUSIONS
  The described S and SR measurements with TDI-ST are comparable to conventional manual analysis. Thus, using TDI-ST, it is possible to quickly and easily extract high-resolution deformation data.
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Medical University of Graz, Graz, Austria.|Division of General Radiology, Department of Radiology, Medical University of Graz, Graz, Austria.
authors.forename: Johannes
authors.identifier: http://orcid.org/0000-0001-8884-7924
authors.initials: J
authors.lastname: Schmid
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Medical University of Graz, Graz, Austria.
authors.forename: Reinhard
authors.initials: R
authors.lastname: Kaufmann
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Medical University of Graz, Graz, Austria.
authors.forename: Martin R
authors.initials: MR
authors.lastname: Grübler
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Medical University of Graz, Graz, Austria.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Verheyen
authors.affiliation: Department of Cardiology, Katharinen-Hospital Unna, Unna, Germany.|Comprehensive Heart Failure Center, Würzburg, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Weidemann
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Medical University of Graz, Graz, Austria.
authors.forename: Josepha S
authors.initials: JS
authors.lastname: Binder
mesh_terms: D000328:Adult; D000465:Algorithms; D018618:Echocardiography, Doppler, Color / Q000379:methods*; D055119:Elastic Modulus; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D010363:Pattern Recognition, Automated / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000503:physiopathology*
keywords: left ventricular function; myocardial contraction; myocardial strain; strain; strain rate imaging; tissue Doppler imaging