title: Noninvasive clinical assessment of systolic torsional motions by two-dimensional speckle-tracking echocardiography in dogs with myxomatous mitral valve disease.
abstract: BACKGROUND
  Left ventricular torsional motion plays an important role for effective pump function. However, noninvasive clinical assessment of torsional deformations by two-dimensional speckle-tracking echocardiography (2D-STE) in dogs with myxomatous mitral valve disease (MMVD) has not been reported.
  
  
  OBJECTIVE
  Left ventricular torsion is determined by the native orientation of the helical myocardial fibers, such that it might provide better assessment of myocardial function than conventional methods.
  
  
  METHODS
  Sixty-seven client-owned dogs with MMVD were classified into 3 classes based on the International Small Animal Cardiac Health Council classification and 16 weight- and age-matched healthy dogs.
  
  
  METHODS
  Dogs were examined for myocardial deformations by 2D-STE and were evaluated for peak systolic rotation and rotation rate at each basal and apical view. Dogs also were evaluated for peak systolic torsion and torsion rate.
  
  
  RESULTS
  Peak systolic torsion was higher in class II than in class I (P < .001) dogs. Peak systolic torsion was lower in class III than in class II (P = .001) dogs and controls (P = .003).
  
  
  CONCLUSIONS
  Torsional deformations assessed by 2D-STE differed among clinical classes of MMVD. Myocardial torsional deformations by 2D-STE may provide more detailed assessment of contractile function in dogs with MMVD.
authors.affiliation: Division of Veterinary Internal Medicine, Department of Veterinary Science, Faculty of Veterinary Medicine, Nippon Veterinary and Life Science University, Tokyo, Japan. d01005@nvlu.ac.jp
authors.forename: R
authors.initials: R
authors.lastname: Suzuki
authors.forename: H
authors.initials: H
authors.lastname: Matsumoto
authors.forename: T
authors.initials: T
authors.lastname: Teshima
authors.forename: H
authors.initials: H
authors.lastname: Koyama
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D004283:Dog Diseases / Q000145:classification / Q000000981:diagnostic imaging* / Q000503:physiopathology; D004285:Dogs; D004452:Echocardiography / Q000379:methods / Q000662:veterinary*; D005260:Female; D006321:Heart / Q000502:physiology; D008297:Male; D008945:Mitral Valve Prolapse / Q000145:classification / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000662:veterinary*; D013599:Systole; D014102:Torsion Abnormality / Q000000981:diagnostic imaging / Q000662:veterinary*