Strategies for Diagnosis of Fetal right atrium dilation: Based on fetal cardiac anatomy and hemodynamics

• DOI: 10.21203/rs.2.24478/v2
• Publication Date: 2020-06-03T18:18:36Z
• Authors: Yu Wang; Leisheng Zhao; Ying Zhang
• Keywords: Echocardiography, Doppler, Pulsed; Heart Defects, Congenital; Fetal echocardiography; Right atrium dilation; Hemodynamics; Echocardiography, Doppler, Color; 3. Good health; 03 medical and health sciences; Fetal Heart; 0302 clinical medicine; Pregnancy; Prenatal Diagnosis; Medical technology; Humans; Female; R855-855.5; Research Article; Retrospective Studies

Abstract Background: Fetal right atrium (RA) dilation is frequently detected in routine screenings while it remains a challenge to clarify the reasons. This study aimed to analyze the cardiac anatomy and hemodynamics of fetal RA dilation and the changes of hemodynamic indexes. Methods: In the retrospective study, 420 fetuses with RA dilation were included, which were classified into the physiological group (n=202), volume overload group (n=142), and the pressure overload group (n=76). The ratio of right atrium to left atrium (RA/LA) were measured at four-chamber view. Peak velocity of tricuspid regurgitation (VTR) was recorded in each case, if existed. Results: The RA/LA ratio in the volume overload group is significantly higher than both the pressure overload group and the physiological group (both P=0.000) throughout the pregnancy while no difference presents between the pressure overload group and the physiological group (P=0.694 for 19-31 GW, and P=0.974 for 32-36 GW, respectively). The VTR in the pressure overload group (3.29±0.58 m/s) is significantly higher than both the volume overload group (1.85±0.45 m/s, P=0.000) and the physiological group (0.88±0.45 m/s, P=0.000). The volume overload group shows a significantly higher VTR than the physiological group (P=0.000). In the volume overload group, the ductal contraction/closure shows a significantly higher VTR than that in the pulmonary valve stenosis/atresia (3.98±0.41 m/s vs. 3.03±0.38 m/s, P=0.000).Conclusions: A strategy proposed herein is useful to clarify the reasons for RA dilatation by systematically assessing fetal hemodynamics, which may facilitate the sonographers to make an accurate diagnosis of CHD.