Assessment of Left Atrial Function in Normal Fetuses Using Speckle Tracking Analysis: Implications for Diastolic Function

Abstract Introduction: Fetal echocardiography is a valuable diagnostic tool for evaluating the structure and function of the fetal heart. However, assessing fetal left atrial (LA) function in various phases remains challenging, and the relationship between fetal LA and diastolic function is unknown. We used two-dimensional speckle-tracking echocardiography (2D-STE) to assess LA function in healthy fetuses in different stages and evaluated the relationship between fetal LA function and diastolic function. Materials and methods This single-center prospective study included 225 healthy women with normal singleton pregnancies. At three gestational ages, 23–24 weeks, 32–33 weeks, and 36–37 weeks, 2D-STE was performed to obtain the LA strain and strain rate in the reservoir, conduit, and contraction phases. Parameters of left ventricular (LV) diastolic function, including global longitudinal early peak LV strain rate, global longitudinal late peak LV strain rate, diastolic strain rate e/a ratio, and mitral Doppler inflow pattern E/A ratio were measured and correlated with LA strain parameters. Results Of the 225 cases, 198 (88%) were included in the analysis. Compared with measurements in the second trimester, during the third trimester, both LA strain and strain rate were lower during the reservoir and contraction phases, while the LA strain was more significant during the conduit phase (all p < 0.05). The LA strain and strain rate in the contraction phase showed a significant correlation with the parameters of LV diastolic function. Conclusions Our study findings suggest that LA contraction function correlates strongly with LV diastolic function in fetuses. Thus, monitoring changes in atrial function throughout gestation can be valuable for assessing fetal cardiac maturation and identifying abnormal fetal cardiac position.