The mitral annular displacement by two-dimensional speckle tracking: a new tool in evaluating the left atrial function.

Background: The methods used to characterize the volume change and the deformation of the left atrium are highly dependent on technical factors and difficult to use in a clinical environment. The aim of this study was to demonstrate that mitral annular displacement by speckle tracking can be an alternative method to studying the longitudinal left atrial function.

Methods: Ninety study participants (54% men), with a mean age of 53(±15) years, underwent a complete echocardiographic examination, comprising two-dimensional, three-dimensional and tissue Doppler imaging (TDI). They were divided into normal individuals (35) and patients having an abnormal echocardiography (55).

Results: There was a very strong correlation between three-dimensional volumetric function and mitral annular displacement, both for the reservoir (r = 0.78; P < 0.0001) and contractile (r = 0.76; P < 0.0001) functions. The correlation with the longitudinal strain displayed an r = 0.87, P > 0.0001 for the reservoir and r = 0.81, P < 0.0001 for the contractile function. The systolic speed in pulsed TDI and the systolic displacement had an r = 0.83, P < 0.0001. Mitral annular displacement was a very good discriminator for normal versus abnormal participants [area under the curve (AUC) for reservoir = 0.872 and for contractile = 0.843; P < 0.0001], performing less well than three-dimensional (AUC reservoir = 0.892 and contractile = 0.915; P < 0.0001) or deformation (AUC = 0.921 and 0.903 respectively; P < 0.0001), but better than pulsed TDI (AUC = 0.807; P < 0.0001). The percentage error was ±15% for interobserver and ±12% for intraobserver variability. The time taken for displacement analysis was 9 ± 3 s for an experienced cardiologist and 12 ± 4 s for a beginner.

Conclusion: Mitral annular displacement by speckle tracking is a reliable and fast method to evaluate left atrial function. Given the strength of the correlations with strain parameters, it could be used as a surrogate measure of the deformation of left atrium.