胎儿单纯性完全型肺静脉异位引流的产前诊断

Prenatal diagnosis of simple total anomalous pulmonary venous connection in fetus

目的:探讨胎儿单纯性完全型肺静脉异位引流(TAPVC)超声图像特点及产前诊断。方法:回顾性分析2010年6月至2015年11月在广东省妇幼保健院超声诊断并经病理解剖证实或出生后影像学检查证实的13例胎儿单纯性TAPVC的产前超声图像特征。结果:产前诊断10例胎儿单纯性TAPVC,其中心上型3例、心内型4例、心下型3例;产前未检出3例,每型各1例。单纯性TAPVC的产前诊断线索:(1)直接征象:二维超声至少清晰显示1条以上肺静脉开口于左房,并且采用CDFI辅助显示该条肺静脉回流至左心房,即可排除TAPVC。(2)间接征象:(1)四腔心切面:左房后壁光滑,未显示静脉角;左房后壁与降主动脉间距增宽;多数病例在左房后方显示异常腔隙(即共同静脉腔)。(2)三血管-气管切面:出现异常血管回声;腔静脉比例增宽。(3)腹围切面:降主动脉与下腔静脉之间显示异常血管回声(心下型TAPVC特有征象)。(4)妊娠后期,右心系统增大时,注意排除TAPVC。结论:单纯性TAPVC在孕中期易被漏诊,应注意多角度、多切面扫查;孕晚期胎儿超声心动图检查可减少漏诊。当胎儿出现右心系统增大时,要注意排查TAPVC;当产前检查未能发现导致胎儿右心系统增大的病变时,出生后仍应及时行超声心动图或心脏CT检查,有利于产前漏诊的患儿能早期诊断、评估及治疗。

Objective：To investigate the ultrasonographic characteristics and prenatal diagnosis of simple total anomalous pulmonary venous connection （ TAPVC ） in fetus. Methods： A retrospective analysis was performed on prenatal ultrasonographic characteristics of 13 cases of simple TAPVC diagnosed in Guangdong Provincial Maternal and Child Health Hospital either by prenatal ultrasonography and confirmatory pathology or postnatal imaging study. Results： Ten cases of simple TAPVC fetus were identified prenatally, including 3 of supracardiac connection,4 of cardiac connnection and 3 of infracardiac connection. Prenatal diagnosis failed to detect three cases-one case of each type-of TAPVC. Several clues for prenatal diagnosis of TAPVC were： （ 1） direct signs：one or more pulmonary vein openings to the left atrium were clearly visible even on two-dimensional ultrasound;pulmonary venous return to the left atrium via these opening was shown with auxiliary CDFI. These signs may rule out TAPVC. （2） indirect signs：① four-chamber view indicated smooth posterior wall of the left atrium without venous angle,widened spacing between posterior wall of the left atrium and the descending aorta, and in most of cases,an abnormal space behind the left atrium （ pulmonary venous confluence）;②three-vessel-trachea view indicated abnormal vascular echo and widened venous lumen ratio. ③ abdominal circumference section showed abnormal vascular echo between the aorta and inferior vena cava （ unique signs of infracardiac TAPVC）; ④ right-sided cardiomegaly during late pregnancy should prompt alert for TAPVC. Conclusion：Simple TAPVC can be easily neglected during the second trimester,and therefore ultrasound scanning needs to be performed in multiple angles and sections. Fetal echocardiography during late pregnancy may reduce misdiagnosis. Right-sided cardiomegaly in a fetus should prompt alert for TAPVC. When prenatal investigations fail to determine the causes of fetal right-sided cardiomegaly,echocardiography or cardiac CT early after birth remains necessary and may help early diagnosis,evaluation and treatment of the prenatally neglected TAPVC.