title: Feasibility of strain and strain rate evaluation by two-dimensional speckle tracking in murine model of myocardial infarction:  comparison with tissue Doppler echocardiography.
abstract: BACKGROUND
  Echocardiography has become a useful tool for serial evaluation of cardiac phenotype in mice. We aimed to examine the feasibility and reproducibility of advanced echocardiographic methods: two-dimensional speckle tracking (STE) and tissue Doppler echocardiography (TDE) in assessing strain and strain rate for analysis of myocardial infarction (MI) in a murine model.
  
  
  METHODS
  We examined 10 anesthetized mice (of which five had MI and five had a normal heart) in parasternal short-axis view with the use of an M12L (14 MHz) transducer. The data were analyzed off-line by two independent investigators using standard echocardiographic parameters and radial strain and strain rate from TDE and STE.
  
  
  RESULTS
  Reproducibility of analyzed parameters was high. A good correlation was found between strain and strain rate values measured from TDE and STE obtained by two investigators, reaching a correlation coefficient (r) from 0.94 to 0.99 for strain and from 0.90 to 0.98 for strain rate. The correlation coefficients between radial peak systolic TDE-dependent strain/strain rate vs. strain/strain rate measured from STE for anterior and posterior walls were: r=0.33 (P=0.35)/r=0.69 (P=0.03) and r=0.86 (P=0.0012)/r=0.75 (P=0.01), respectively. Values of strain/strain rate reflected well to pathophysiology of MI in mice.
  
  
  CONCLUSIONS
  We conclude that local myocardial function can be analyzed in mice using STE. This approach is rapid, reproducible and less time-consuming than TDE measurements in normal mice and in the MI model. STE alone, or combined with tissue Doppler imaging, is suitable for computer-assisted measurements of regional myocardial deformation in mice.
authors.affiliation: Department of Cardiology, Medical University of Lodz, Bieganski Hospital, Lodz, Poland.
authors.forename: Ewa
authors.initials: E
authors.lastname: Szymczyk
authors.forename: Piotr
authors.initials: P
authors.lastname: Lipiec
authors.forename: Michał
authors.initials: M
authors.lastname: Plewka
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Białas
authors.forename: Marta
authors.initials: M
authors.lastname: Olszewska
authors.forename: Natalia
authors.initials: N
authors.lastname: Rozwadowska
authors.forename: Karol
authors.initials: K
authors.lastname: Kamiński
authors.forename: Maciej
authors.initials: M
authors.lastname: Kurpisz
authors.forename: Błażej
authors.initials: B
authors.lastname: Michalski
authors.forename: Jarosław D
authors.initials: JD
authors.lastname: Kasprzak
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D004452:Echocardiography / Q000379:methods*; D015150:Echocardiography, Doppler; D005240:Feasibility Studies; D008297:Male; D051379:Mice; D009200:Myocardial Contraction / Q000502:physiology*; D009203:Myocardial Infarction / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D015203:Reproducibility of Results; D013599:Systole; D016277:Ventricular Function, Left / Q000502:physiology*