title: Comparison of magnetic resonance feature tracking for systolic and diastolic strain and strain rate calculation with spatial modulation of magnetization imaging analysis.
abstract: OBJECTIVE
  To compare cardiovascular magnetic resonance-feature tracking (CMR-FT) with spatial modulation of magnetization (SPAMM) tagged imaging for the calculation of short and long axis Lagrangian strain measures in systole and diastole.
  
  
  METHODS
  Healthy controls (n = 35) and patients with dilated cardiomyopathy (n = 10) were identified prospectively and underwent steady-state free precession (SSFP) cine imaging and SPAMM imaging using a gradient-echo sequence. A timed offline analysis of images acquired at identical horizontal long and short axis slice positions was performed using CMR-FT and dynamic tissue-tagging (CIMTag2D). Agreement between strain and strain rate (SR) values calculated using these two different methods was assessed using the Bland-Altman technique.
  
  
  RESULTS
  Across all participants, there was good agreement between CMR-FT and CIMTag for calculation of peak systolic global circumferential strain (-22.7 ± 6.2% vs. -22.5 ± 6.9%, bias 0.2 ± 4.0%) and SR (-1.35 ± 0.42 1/s vs. -1.22 ± 0.42 1/s, bias 0.13 ± 0.33 1/s) and early diastolic global circumferential SR (1.21 ± 0.44 1/s vs. 1.07 ± 0.30 1/s, bias -0.14 ± 0.34 1/s) at the subendocardium. There was satisfactory agreement for derivation of peak systolic global longitudinal strain (-18.1 ± 5.0% vs. -16.7 ± 4.8%, bias 1.3 ± 3.8%) and SR (-1.04 ± 0.29 1/s vs. -0.95 ± 0.32 1/s, bias 0.09 ± 0.26 1/s). The weakest agreement was for early diastolic global longitudinal SR (1.10 ± 0.40 1/s vs. 0.67 ± 0.32 1/s, bias -0.42 ± 0.40 1/s), although the correlation remained significant (r = 0.42, P < 0.01). CMR-FT generated these data over four times quicker than CIMTag.
  
  
  CONCLUSIONS
  There is sufficient agreement between systolic and diastolic strain measures calculated using CMR-FT and myocardial tagging for CMR-FT to be considered as a potentially feasible and rapid alternative.
authors.affiliation: Department of Cardiology, Nuffield House, Queen Elizabeth Hospital Birmingham, Edgbaston, Birmingham, UK; Centre for Cardiovascular Sciences, School of Clinical and Experimental Medicine, University of Birmingham, Edgbaston, Birmingham, UK.
authors.forename: William E
authors.initials: WE
authors.lastname: Moody
authors.forename: Robin J
authors.initials: RJ
authors.lastname: Taylor
authors.forename: Nicola C
authors.initials: NC
authors.lastname: Edwards
authors.forename: Colin D
authors.initials: CD
authors.lastname: Chue
authors.forename: Fraz
authors.initials: F
authors.lastname: Umar
authors.forename: Tiffany J
authors.initials: TJ
authors.lastname: Taylor
authors.forename: Charles J
authors.initials: CJ
authors.lastname: Ferro
authors.forename: Alistair A
authors.initials: AA
authors.lastname: Young
authors.forename: Jonathan N
authors.initials: JN
authors.lastname: Townend
authors.forename: F
authors.initials: F
authors.lastname: Leyva
authors.forename: Richard P
authors.initials: RP
authors.lastname: Steeds
mesh_terms: D000328:Adult; D002311:Cardiomyopathy, Dilated / Q000150:complications / Q000503:physiopathology*; D003971:Diastole; D055119:Elastic Modulus; D054459:Elasticity Imaging Techniques / Q000379:methods*; D006352:Heart Ventricles / Q000503:physiopathology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008875:Middle Aged; D010363:Pattern Recognition, Automated / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D033081:Shear Strength; D013314:Stress, Mechanical; D013599:Systole; D018754:Ventricular Dysfunction / Q000209:etiology / Q000503:physiopathology*
keywords: cine magnetic resonance imaging; feature tracking; left ventricular function; tagging