Impact of Diastolic Dysfunction Grade on Left Atrial Mechanics Assessed by Two-Dimensional Speckle Tracking Echocardiography

Abstract

Mitral inflow patterns reflect not only left ventricular diastolic function but also left atrial (LA) remodeling. The aim of this study was to determine the effects of left ventricular diastolic dysfunction on LA volumetric and functional parameters assessed using two-dimensional speckle-tracking echocardiography. Two-dimensional speckle-tracking analysis of the LA wall in the apical four-chamber view was performed in 268 subjects. Subjects were classified according to diastolic dysfunction grade. Indexed maximum and minimum LA volumes and indexed LA volume before atrial contraction were measured from LA volume waveforms. Expansion, passive emptying, and active emptying indices were calculated. LA volumes increased progressively with advanced stages of diastolic dysfunction. The expansion index and passive emptying index showed progressive decreases according to the grade of diastolic dysfunction. The active emptying index increased until mild diastolic dysfunction and thereafter progressively decreased until reaching severe diastolic dysfunction. Significant correlations were noted between the active emptying index and A-wave velocity (r = 0.31, P < .01) and between the E/E' ratio and the expansion index (r = 0.56, P < .01). LA volumes and functional parameters derived from two-dimensional speckle-tracking echocardiography vary according to the level of diastolic dysfunction. These results suggest that left ventricular diastolic dysfunction also predicts the severity of LA remodeling.