Liu Meixin, Yu Jing, Fu Xiuxiu, Wan Wei
The Affiliated Hospital of Qingdao University, Qingdao, Shinan, China (mainland).
Med Sci Monit. 2015 Oct 2;21:2956-68. doi: 10.12659/MSM.894381.
The study aimed to investigate the clinical value of velocity vector imaging (VVI) in assessing heart function in fetuses of pregnant women with thyroid dysfunction. The inter-observer and intra-observer variability was assessed for all VVI parameters observed.
The participants were enrolled from singleton pregnant women with gestational ages ranging 24+0 to 40+1 weeks who visited the Department of Obstetrics and Gynecology at the Affiliated Hospital of Qingdao University, China, for prenatal care from July 2011 to February 2014. Digital 2-dimensional (2D) dynamic 4-chamber images of the heart were collected. A total of qualified 226 images from 125 fetuses of pregnant women with normal thyroid (control group), 64 fetuses of pregnant women with hypothyroidism (hypothyroidism group), and 37 fetuses of pregnant women with hyperthyroidism (hyperthyroidism group) were interrogated offline using VVI software. The echocardiographic parameters including the myocardium peak systolic velocity (Vs), peak diastolic velocity (Vd), peak systolic strain (S), peak systolic strain rate (SRs), peak diastolic strain rate (SRd) of RV and LV, were obtained from the velocity curves of 2D myocardial motion. The heart rate was measured using a virtual M-mode algorithm built into the software.
The study found that the longitudinal Vs and Vd of both ventricles in the control group gradually decreased from basal segments to apical segments and significantly increased over the gestation. S, SRs, and SRd of both ventricles remained stable after middle gestation. Compared with the control group, the hypothyroidism and hyperthyroidism groups exhibited significantly reduced S, SRs, and SRd, even for fetuses at 24-weeks gestation. There were no significant differences in global Vs and global Vd between the control group and the hyperthyroidism or hypothyroidism groups.
The thyroid dysfunction of pregnant women may damage fetal heart function, and VVI could be a sensitive technique to measure the variation of fetal heart function.
本研究旨在探讨速度向量成像（VVI）在评估甲状腺功能异常孕妇胎儿心脏功能中的临床价值。对所有观察到的VVI参数进行观察者间和观察者内变异性评估。
研究对象为2011年7月至2014年2月在中国青岛大学附属医院妇产科进行产前检查的单胎孕妇，孕周为24 + 0至40 + 1周。采集心脏的数字二维（2D）动态四腔图像。使用VVI软件对来自125例甲状腺功能正常孕妇的胎儿（对照组）、64例甲状腺功能减退孕妇的胎儿（甲状腺功能减退组）和37例甲状腺功能亢进孕妇的胎儿（甲状腺功能亢进组）的总共226张合格图像进行离线分析。从二维心肌运动速度曲线中获取超声心动图参数，包括右心室和左心室的心肌收缩期峰值速度（Vs）、舒张期峰值速度（Vd）、收缩期峰值应变（S）、收缩期峰值应变率（SRs）、舒张期峰值应变率（SRd）。使用软件内置的虚拟M型算法测量心率。
研究发现，对照组两心室的纵向Vs和Vd从基底部到心尖部逐渐降低，并在孕期显著增加。两心室的S、SRs和SRd在孕中期后保持稳定。与对照组相比，甲状腺功能减退组和甲状腺功能亢进组即使在孕24周时胎儿的S、SRs和SRd也显著降低。对照组与甲状腺功能亢进组或甲状腺功能减退组之间的整体Vs和整体Vd无显著差异。
孕妇甲状腺功能异常可能损害胎儿心脏功能，VVI可能是一种测量胎儿心脏功能变化的敏感技术。
