title: Systolic cardiac function assessment by feature tracking echocardiography in dogs with myxomatous mitral valve disease.
abstract: OBJECTIVE
  To evaluate endomyocardial and epimyocardial left ventricular circumferential and longitudinal peak systolic strain and strain rate in dogs with myxomatous mitral valve disease using two-dimensional feature tracking imaging echocardiography.
  
  
  METHODS
  Epimyocardial and endomyocardial global and regional myocardial peak systolic strain and strain rate using two-dimensional feature tracking imaging were evaluated in healthy dogs and those in stages B1, B2 and C of myxomatous mitral valve disease. Strain and strain rate in circumferential and longitudinal aspect were evaluated in 48 small- and medium-sized dogs.
  
  
  RESULTS
  Global endomyocardial circumferential strain and global epimyocardial circumferential strain systolic peak were lower in stage C than in stage B2 (P = 0 · 04 and P = 0 · 02) and similar to healthy dogs. Endomyocardial circumferential strain rate in septal and inferior segments were lower in stage C compared to B2 (P = 0 · 0007 and P = 0 · 0056), but not different from healthy dogs. There were no statistical differences in the epimyocardial circumferential strain rate, longitudinal strain and strain rate between healthy and affected dogs.
  
  
  CONCLUSIONS
  Two-dimensional feature tracking imaging determination of myocardial deformation in epimyocardial and endomyocardial layers allows detection of increased compensatory circumferential left ventricular myocardial systolic performance due to volume overload and absence of this response as disease advances to congestive heart failure.
authors.affiliation: Department of Veterinary Medicine, Federal University of Lavras, Lavras, 37200-000, MG, Brazil.
authors.forename: M M
authors.initials: MM
authors.lastname: Mantovani
authors.affiliation: Department of Veterinary Medicine, Federal University of Lavras, Lavras, 37200-000, MG, Brazil.
authors.forename: R A L
authors.initials: RA
authors.lastname: Muzzi
authors.affiliation: Veterinary Cardiology, Naya Specialties, São Paulo, 09560-500, SP, Brazil.
authors.forename: G G
authors.initials: GG
authors.lastname: Pereira
authors.affiliation: Veterinary Cardiology, Naya Specialties, São Paulo, 09560-500, SP, Brazil.
authors.forename: R J
authors.initials: RJ
authors.lastname: Yamato
authors.affiliation: Department of Veterinary Medicine, Federal University of Lavras, Lavras, 37200-000, MG, Brazil.
authors.forename: A C
authors.initials: AC
authors.lastname: Silva
authors.affiliation: Department of Veterinary Medicine, Federal University of Lavras, Lavras, 37200-000, MG, Brazil.
authors.forename: G F
authors.initials: GF
authors.lastname: Reis
authors.affiliation: Department of Veterinary Medicine, Federal University of Lavras, Lavras, 37200-000, MG, Brazil.
authors.forename: L A L
authors.initials: LA
authors.lastname: Muzzi
authors.affiliation: Faculty of Mathematics, Federal University of Uberlândia, Uberlândia, MG, Brazil.
authors.forename: E C
authors.initials: EC
authors.lastname: Guimarães
mesh_terms: D000818:Animals; D016022:Case-Control Studies; D004283:Dog Diseases / Q000000981:diagnostic imaging*; D004285:Dogs; D005260:Female; D008297:Male; D008945:Mitral Valve Prolapse / Q000000981:diagnostic imaging / Q000662:veterinary*; D011237:Predictive Value of Tests; D013599:Systole; D018615:Ultrasonography, Doppler, Color / Q000662:veterinary*; D018487:Ventricular Dysfunction, Left / Q000503:physiopathology