title: Quantitative analysis of left ventricular strain using cardiac computed tomography.
abstract: OBJECTIVE
  To investigate whether cardiac computed tomography (CCT) can determine left ventricular (LV) radial, circumferential and longitudinal myocardial deformation in comparison to two-dimensional echocardiography in patients with congestive heart failure.
  
  
  BACKGROUND
  Echocardiography allows for accurate assessment of strain with high temporal resolution. A reduced strain is associated with a poor prognosis in cardiomyopathies. However, strain imaging is limited in patients with poor echogenic windows, so that, in selected cases, tomographic imaging techniques may be preferable for the evaluation of myocardial deformation.
  
  
  METHODS
  Consecutive patients (n=27) with congestive heart failure who underwent a clinically indicated ECG-gated contrast-enhanced 64-slice dual-source CCT for the evaluation of the cardiac veins prior to cardiac resynchronization therapy (CRT) were included. All patients underwent additional echocardiography. LV radial, circumferential and longitudinal strain and strain rates were analyzed in identical midventricular short axis, 4-, 2- and 3-chamber views for both modalities using the same prototype software algorithm (feature tracking). Time for analysis was assessed for both modalities.
  
  
  RESULTS
  Close correlations were observed for both techniques regarding global strain (r=0.93, r=0.87 and r=0.84 for radial, circumferential and longitudinal strain, respectively, p<0.001 for all). Similar trends were observed for regional radial, longitudinal and circumferential strain (r=0.88, r=0.84 and r=0.94, respectively, p<0.001 for all). The number of non-diagnostic myocardial segments was significantly higher with echocardiography than with CCT (9.6% versus 1.9%, p<0.001). In addition, the required time for complete quantitative strain analysis was significantly shorter for CCT compared to echocardiography (877±119 s per patient versus 1105±258 s per patient, p<0.001).
  
  
  CONCLUSIONS
  Quantitative assessment of LV strain is feasible using CCT. This technique may represent a valuable alternative for the assessment of myocardial deformation in selected patients with poor echogenic windows and general contraindications for magnetic resonance imaging.
authors.affiliation: Department of Cardiology, University of Heidelberg, 69120 Heidelberg, Germany. Electronic address: sebastian.buss@med.uni-heidelberg.de.
authors.forename: Sebastian J
authors.initials: SJ
authors.lastname: Buss
authors.affiliation: Department of Cardiology, University of Heidelberg, 69120 Heidelberg, Germany.
authors.forename: Felix
authors.initials: F
authors.lastname: Schulz
authors.affiliation: Department of Cardiology, University of Heidelberg, 69120 Heidelberg, Germany.
authors.forename: Derliz
authors.initials: D
authors.lastname: Mereles
authors.affiliation: Department of Diagnostic and Interventional Radiology, University of Heidelberg, 69120 Heidelberg, Germany.
authors.forename: Waldemar
authors.initials: W
authors.lastname: Hosch
authors.affiliation: TomTec Imaging Systems GmbH, Munich, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Galuschky
authors.affiliation: TomTec Imaging Systems GmbH, Munich, Germany.
authors.forename: Georg
authors.initials: G
authors.lastname: Schummers
authors.affiliation: TomTec Imaging Systems GmbH, Munich, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Stapf
authors.affiliation: Department of Cardiology, University of Heidelberg, 69120 Heidelberg, Germany.
authors.forename: Nina
authors.initials: N
authors.lastname: Hofmann
authors.affiliation: Department of Cardiology, University of Heidelberg, 69120 Heidelberg, Germany.
authors.forename: Evangelos
authors.initials: E
authors.lastname: Giannitsis
authors.affiliation: Department of Cardiology, University of Heidelberg, 69120 Heidelberg, Germany.
authors.forename: Stefan E
authors.initials: SE
authors.lastname: Hardt
authors.affiliation: Department of Diagnostic and Interventional Radiology, University of Heidelberg, 69120 Heidelberg, Germany.
authors.forename: Hans-Ulrich
authors.initials: HU
authors.lastname: Kauczor
authors.affiliation: Department of Cardiology, University of Heidelberg, 69120 Heidelberg, Germany.
authors.forename: Hugo A
authors.initials: HA
authors.lastname: Katus
authors.affiliation: Department of Cardiology, University of Heidelberg, 69120 Heidelberg, Germany.
authors.forename: Grigorios
authors.initials: G
authors.lastname: Korosoglou
mesh_terms: D000368:Aged; D016880:Anisotropy; D004452:Echocardiography / Q000379:methods; D055119:Elastic Modulus; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005069:Evaluation Studies as Topic; D006333:Heart Failure / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013314:Stress, Mechanical; D014057:Tomography, X-Ray Computed / Q000379:methods*; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000209:etiology / Q000503:physiopathology*
keywords: Cardiac CT; Congestive heart failure; Left ventricular function; Two-dimensional strain echocardiography