Correlations between left atrial volumes and strains in healthy adults: Detailed analysis from the three-dimensional speckle-tracking echocardiographic MAGYAR-Healthy Study.

INTRODUCTION: Little is known about the relationship between left atrium (LA) volumes and contractility features along the cardiac cycle. The present study aimed to assess, by three-dimensional speckle-tracking echocardiography (3DSTE), correlations between LA volumes, volume-based functional properties, and strains during the cardiac cycle in healthy adults. METHODS: We included 217 healthy adult volunteers (mean age 33.4 ± 12.7 years, 112 males) who underwent complete two-dimensional Doppler echocardiography with 3DSTE. RESULTS: LA stroke volumes were greater in subjects with the greater maximum LA volume (Vmax ) in reservoir, conduit, and booster pump phases of LA function. While LA emptying fraction in LA reservoir phase was not different between subjects depending in their Vmax value, a significantly lower LA emptying fraction could be detected in LA conduit phase in subjects whose Vmax was >50 mL. In booster pump function, LA emptying fraction was not significantly different whatever the Vmax . Only global and mean segmental peak LA radial strain (RS) and 3D strain (3DS) and the same strains at atrial contraction appeared greater in subjects with greater Vmax , whereas the other strain parameters were not different. CONCLUSIONS: In healthy subjects, LA-RS and LA-3DS, objective features of LA contractility, are greater in subjects with greater LA volumes up to a point beyond which this association disappears.