摘要目的：采用胎儿超声心动图评价存在单纯永存左上腔静脉(PLSVC)连接至冠状静脉窦的胎儿心脏结构和血流动力学特点，探讨单纯 PLSVC 对胎儿心脏结构发育有无影响。方法随机选取单纯PLSVC的中孕期(23~27+6周)胎儿22例，晚孕期(28~39+6周)胎儿20例；孕期相匹配的心脏结构正常的中孕期胎儿25例，晚孕期胎儿24例；测量4组胎儿的心脏结构大小参数：左、右心大小，卵圆孔直径，主动脉内径，主动脉峡部内径，肺动脉内径；计算右心/左心比例、肺动脉/主动脉内径比例；测量血流动力学指标：二尖瓣血流速度、三尖瓣血流速度、卵圆孔血流速度，将 PLSVC 组胎儿分别与正常心脏组胎儿的上述指标进行对照分析。结果中孕期 PLSVC 组胎儿的右室/左室比值、肺动脉/主动脉比值明显大于正常组；主动脉及主动脉峡部内径则明显小于正常组(P <0.05)。晚孕期 PLSVC 组胎儿的肺动脉/主动脉比值大于正常组，主动脉峡部内径明显小于正常组(P <0.05)。结论胎儿期单纯PLSVC连接冠状静脉窦时其心脏结构与正常胎儿存在一定不同；PLSVC导致的扩张的冠状静脉窦对胎儿心脏结构发育有一定影响。

abstractsObjective To investigate the difference in cardiac structure and hemodynamics characteristics between fetuses with isolated persistent left superior vena cava (LSVC)and normal fetuses by using fetal echocardiography,in order to explore whether isolated PLSVC has some influence on the development of fetal heart structure development.Methods Twenty-two fetuses diagnosed with isolated PLSVC in the second and third trimester were enrolled in this study.The PLSVC fetuses were divided into two groups:group 1 ,twenty-two fetuses in the second trimester (23-27+6 W);group 2,twenty fetuses in the third trimester (28-39+6 W).Forty-nine fetuses without intra-cardiac and extra-cardiac anomalies with gestation age matched were involved as normal control groups:25 fetuses in the second trimester,and 24 fetuses in the third trimester.The parameters of cardiac structure and hemodynamics of the four groups were measured,including left and right sideheart size,the diameter of foramen ovale(FO),aorta(AO),aortic isthmus and pulmonary artery (PA).The ratio of RV/LV,RA/LA and PA/AO were calculated.The hemodynamic parameters included the flow velocity across mitral valve(MV),tricuspid valve(TV)and FO. All the parameters of PLSVC groups were compared with the normal groups respectively.Results In the second trimester group,the ratio of RV/LV and PA/AO of the PLSVC fetuses were significantly larger than normal,while the AO diameter,aortic isthmus diameter were smaller than normal group (P <0.05). However in the third trimester group,only the ratio of PA/AO of the PLSVC group was significantly greater,and the aortic isthmus diameter was still smaller than the normal group (P <0.05).Conclusions Isolated PLSVC connected with coronary sinus is associated with structural differences from normal.A dilated coronary sinus may have an influence on the development of fetal left heart structures.