Mei Pan1, Ming-Xuan Zhang2, Bo-Wen Zhao1, Yan-Kai Mao1, Xiao-Hui Peng1, Yuan Yang1, Bei Wang1. 1. Department of Diagnostic Ultrasound and Echocardiography, Sir Run Run Shaw Hospital, Zhejiang University College of Medicine, No.3 East Qingchun Road, Hangzhou, 310016, China. 2. Department of Diagnostic Ultrasound and Echocardiography, Sir Run Run Shaw Hospital, Zhejiang University College of Medicine, No.3 East Qingchun Road, Hangzhou, 310016, China. 21618341@zju.edu.cn.
Abstract
OBJECTIVE: To establish a reference range and compare differences among three methods, and then to construct Z-score reference ranges in normal fetuses from the three methods to provide an extra tool for fetal conduction time assessment. METHODS: A total of 227 echocardiographic examinations were finally included. Fetal atrioventricular (AV) time and ventriculoatrial (VA) time intervals were measured by three methods: superior vena cava/ascending aorta (SVC/AAO), pulmonary artery/pulmonary vein (PA/PV) and tissue Doppler imaging (TDI). Regression analysis of the mean and standard deviation was performed to establish Z-scores. RESULTS: With the three methods, positive correlations of intervals with gestational age (GA) and fetal heart rate (FHA) were observed, while intervals were negatively correlated with fetal heart rate (FHR). Correlations between VA/AV and GA, FHA and FHR were weak. The general trend of all intervals was towards an increase. In AV intervals, PA/PV revealed the longest mean AV time interval and SVC/AAO showed the shortest interval. In addition, PA/PV revealed the shortest VA interval. CONCLUSION: This study presents not only the reference range of AV and VA intervals with the three methods but also the Z-score reference ranges for these indices against GA and FHA in normal fetuses. Each method has a different reference range, and appropriate application can facilitate diagnosis and treatment.
OBJECTIVE: To establish a reference range and compare differences among three methods, and then to construct Z-score reference ranges in normal fetuses from the three methods to provide an extra tool for fetal conduction time assessment. METHODS: A total of 227 echocardiographic examinations were finally included. Fetal atrioventricular (AV) time and ventriculoatrial (VA) time intervals were measured by three methods: superior vena cava/ascending aorta (SVC/AAO), pulmonary artery/pulmonary vein (PA/PV) and tissue Doppler imaging (TDI). Regression analysis of the mean and standard deviation was performed to establish Z-scores. RESULTS: With the three methods, positive correlations of intervals with gestational age (GA) and fetal heart rate (FHA) were observed, while intervals were negatively correlated with fetal heart rate (FHR). Correlations between VA/AV and GA, FHA and FHR were weak. The general trend of all intervals was towards an increase. In AV intervals, PA/PV revealed the longest mean AV time interval and SVC/AAO showed the shortest interval. In addition, PA/PV revealed the shortest VA interval. CONCLUSION: This study presents not only the reference range of AV and VA intervals with the three methods but also the Z-score reference ranges for these indices against GA and FHA in normal fetuses. Each method has a different reference range, and appropriate application can facilitate diagnosis and treatment.