Assessment of longitudinal systolic function using tissue motion annular displacement in healthy dogs

Introduction

Left ventricular systolic function is one of the main parameters studied in echocardiography. Longitudinal systolic function, however, is less commonly evaluated in routine examinations but may provide early information on systolic dysfunction. The movement of the mitral annulus toward the apex has already been determined as a method for evaluation of longitudinal systolic function in dogs, but the study of this movement by speckle tracking with the tissue motion annular displacement (TMAD) technique has not yet been evaluated.

Animals

One hundred fifty-three client-owned healthy dogs.

Methods

Cross-sectional study. One hundred fifty-three client-owned healthy dogs underwent physical examination, electrocardiography, blood pressure measurement, and a standard and speckle tracking echocardiography. Systolic function was evaluated by global longitudinal strain (GLS) and TMAD. These parameters were compared with the standard echocardiographic data.

Results

A correlation was found between GLS, TMAD, and body weight. Tissue motion annular displacement and GLS were significantly correlated (p < 0.001) with other surrogates of systolic function, including ejection fraction and fractional shortening. There were no differences in TMAD between sexes. The coefficient of variation (CV) of the intraobserver evaluation in the global TMAD (CV 4.44) was slightly higher than that in the GLS (CV 3.74). Also, TMAD was not influenced by heart rhythm and could be acquired more rapidly than GLS.

Conclusions

Tissue motion annular displacement is a rapid and reproducible method for the assessment of left ventricle longitudinal function in healthy dogs. However, more studies are needed to validate the real clinical applicability of TMAD in animals with heart diseases.