ABSTRACT
ObjectiveTo quantitatively evaluate the left atrial function in healthy Chinese population by cardiac magnetic resonance-feature tracking (CMR-FT). MethodsHealthy individuals with normal magnetic resonance examination results were enrolled according to the inclusion criteria. Cardiac long- and short-axis images and cine were obtained using semi-Fourier single-shot technique and balanced steady-state free precession sequence. The left atrial function parameters, including left atrial volume, ejection fraction, strain and strain rate, were measured by 2 independent observers. Two independent sample t test was used to compare the parameters between males and females. One-way analysis of variance was performed to compare the parameters among different age groups. ResultsA total of 63 volunteers were included in this study. Of 63 volunteers, 34 were males and 29 females; and 19 volunteers were aged≤29 years, 23 were aged 30-44 years and 21 were aged≥45 years. The anteroposterior diameter of left atrium was (26.1±4.5) mm, and the transverse diameter was (54.8±5.9) mm. The total ejection fraction of left atrium was (63.5±6.9)%, total strain was (45.9±11.7)%, and total strain rate was (1.5±0.5) s-1. The passive ejection fraction of left atrium was (24.6±9.1)%, passive strain was (22.2±8.1)%, and passive strain rate was (-0.8±0.3) s-1. The active ejection fraction of left atrium was (51.3±8.9)%, active strain was (23.7±9.2)%, and active strain rate was (-1.3±0.5) s-1. There were significant differences in the body surface area, the left atrial diameters, maximal volume and pre-active contraction volume between the males and the females (all P0.05). There were significant differences in the left atrial conduit function among the different age groups (all P0.6, and the Bland-Altman analysis showed better consistency between the two observers. ConclusionCMR-FT can be used to obtain parameters related to left atrial function in healthy Chinese population due to its high repeatability.