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. MATERIAL AND 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.
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. MATERIAL AND 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: Antonio C L Barros Filho; Henrique T Moreira; Beatriz P Dias; Fernando F F Ribeiro; Denise M Tanaka; André Schmidt; Benedito C Maciel; Marcus V Simões; José A Marin-Neto; Minna M D Romano Journal: Physiol Rep Date: 2021-03