title: Cardiac magnetic resonance feature tracking: a novel method to assess myocardial strain. Comparison with echocardiographic speckle tracking in healthy volunteers and in patients with left ventricular hypertrophy.
abstract: BACKGROUND
  Left ventricular longitudinal strain (LV-LS) and strain rate (SR) are sensitive markers of early systolic dysfunction.
  
  
  OBJECTIVE
  To evaluate the feasibility of a novel, cardiac magnetic resonance (CMR) based method known as feature tracking (FT) for the assessment of strain and SR, and to compare the CMR based results to those obtained on standard transthoracic echocardiography (TTE) in healthy volunteers and in patients with left ventricular hypertrophy cardiomyopathy (HCM).
  
  
  METHODS
  Overall, 20 healthy volunteers (ten male, mean age 24 ± 3 years) and 20 consecutive patients with HCM (12 male, mean age 47 ± 19 years) were included. Longitudinal and circumferential strain and SR of the left ventricle were measured on CMR at 1.5 Tesla and TTE and interobserver variability was assessed.
  
  
  RESULTS
  FT measurements were feasible in all subjects. A good agreement between global LV-LS measured on CMR (controls: 20.8 ± 3.0; HCM: 17.6 ± 3.8) and TTE (controls: 19.4 ± 2.1; HCM: 16.6 ± 2.9) was found, while the agreement was worse for circumferential strain and all SR measurements. For the left and right ventricles, interobserver reproducibility was higher for strain measurements compared to SR. Coefficients of variation were lowest for LV-LS (13.2%) by CMR.
  
  
  CONCLUSIONS
  FT analysis is a novel CMR based method for the analysis of myocardial strain and SR that is simple and correlates well with the echocardiographic measurements. Since CMR is unaffected by inadequate acoustic windows, FT may represent an attractive alternative to echocardiography in assessing the increasingly important parameters of myocardial deformation.
authors.affiliation: Department of Cardiology and Angiology, Adult Congenital and Valvular Heart Disease Centre, University Hospital of Muenster, Muenster, Germany. orwat@uni-muenster.de.
authors.forename: Stefan
authors.initials: S
authors.lastname: Orwat
authors.forename: Aleksander
authors.initials: A
authors.lastname: Kempny
authors.forename: Gerhard-Paul
authors.initials: GP
authors.lastname: Diller
authors.forename: Pia
authors.initials: P
authors.lastname: Bauerschmitz
authors.forename: Alexander Ch
authors.initials: ACh
authors.lastname: Bunck
authors.forename: David
authors.initials: D
authors.lastname: Maintz
authors.forename: Robert M
authors.initials: RM
authors.lastname: Radke
authors.forename: Helmut
authors.initials: H
authors.lastname: Baumgartner
mesh_terms: D000328:Adult; D000368:Aged; D004452:Echocardiography / Q000379:methods*; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000175:diagnosis* / Q000000981:diagnostic imaging*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000502:physiology*; D015203:Reproducibility of Results; D013318:Stroke Volume / Q000502:physiology*