超声造影在双胎反向动脉灌注序列征伴心脏遗迹的诊断探讨

The Antenatal Sonographic Diagnosis of Two Cases of Twins Reversed Arterial Perfusion Sequence (TRAP) with Heart Vestige

目的探讨双胎反向动脉灌注序列征伴心脏遗迹的超声造影诊断价值。方法对2例无心畸胎行常规超声检查后,采用造影剂SonoVue行超声造影,造影剂注射方法为静脉缓慢推注,选用微血管成像技术进行实时超声造影,观察造影剂在双胎及脐血管、胎盘中的灌注情况。结果2例无心畸胎胸腔内均可见心脏遗迹搏动,越近遗迹心脏心率越缓慢,越近泵血儿心率越快。超声造影灌注顺序为:泵血儿脐静脉→泵血儿体内→泵血儿脐动脉→胎盘(动脉与动脉吻合)→无心畸胎单一脐动脉→无心畸胎体内→无心畸胎脐静脉→胎盘(静脉与静脉吻合)→泵血儿脐静脉。病理解剖结果:遗迹心脏结构原始,类似原始心管结构。结论遗迹心脏无正常功能,循环仍依赖于泵血儿心脏。超声造影使我们实时观察到无心畸胎、脐血管及胎盘内的血液灌注顺序,为进一步了解无心畸胎循环特点提供重要信息。

Objective To explore the value of contrast-enhanced ultrasound(CEUS) technology in the diagnosis of twins reversed arterial perfusion sequence(TRCP) with heart vestige. Methods 2 patients were examined CEUS after routine ultrasound examinations.A new contrast agent,SonoVue,was injected intravenously as a bolus and a real time contrast enhanced ultrasound with micro flow imaging(MFI)was performed to observe the characteristics of the contrast agent in the twins,umbilical vessels and the placenta.Results In 2 cases we can see the heart vestige beating in the thoracic cavity of the acardiac twin,and closer to the heart vestige the heart rate is also lower,closer to the pump twin the heart rate is also faster.The Contrast-enhanced agent and the blood perfusion sequence is: the pump twin's umbilical vein→the pump twin's body→it's umbilical artery→placenta(artery and arterial anastomosis)→single umbilical artery of the acardiac twin→the acardiac twin's body→it's umbilical vein→placenta(vein and vein anastomosis)→the pump twin's umbilical vein.The autopsy show that the structure of the heart vestige is primitive,and is similar to the heart tube.Conclusion We can observe that the acardiac twin had not normal heart structure and function,it's blood circulation depend on the pump twin,the CEUS can display the blood perfusion sequence in the acardiac twins,umbilical vessel and placenta clearly,and provide important message for us to further understand the acardiac twins' circulation characteristic.