Assessment of left atrial function using tissue motion annular displacement in healthy dogs

Recently, tissue motion annular displacement by speckle tracking has been shown to be a reliable method for evaluating deformation of the left atrium in healthy dogs. The aim of this study was to investigate whether tissue motion annular displacement is a feasible alternative method for studying left atrial function.

One hundred healthy dogs were included. Left atrial function was assessed by tissue motion annular displacement, which was correlated to the left atrial strain and biplane area-length method-derived volumes. Left atrial reservoir function was evaluated by left atrial global tissue motion annular displacement, global left atrial strain and left atrial emptying fraction, while left atrial systolic tissue motion annular displacement and left atrial ejection fraction were used to assess left atrial systolic function.

A statistically significant association between body weight and the dependent variables others than age was found. Indexed global and systolic tissue motion annular displacement decreased as body weight increased. Global iTMAD_AIIometric (mm/∛kg) showed a moderate, positive correlation with left atrial emptying fraction and with global left atrial strain. Systolic iTMAD_AIIometric (mm/∛kg) showed a moderate correlation with left atrial ejection fraction. Coefficients of variation for the intraobserver and interobserver analyses were 8.3% and 20.3% for global and 10.5% and 18.9% for systolic tissue motion annular displacement, respectively.

Tissue motion annular displacement is a feasible and simple method for the evaluation of left atrial function. Our study documented the effects of body weight on left atrial tissue motion annular displacement, indicating that tissue motion annular displacement must be indexed to body weight. No influence of age or heart rate was observed on tissue motion annular displacement.