Twin pregnancy complicated by "twin reversed arterial perfusion" syndrome

We have reported twin pregnancy complicated by uncommon "twin reversed arterial perfusion" syndrome. Ultrasound scan at 27th week of gestation revealed one normal foetus and the second one "acardiac" with severe malformations. Since the cardiac failure of the first twin was observed, the digitalis were administered till the end of pregnancy. The pregnancy was terminated at 31st week by caesarean section. We succeed in delivering one healthy newborn, which was possible by appropriate management including elective termination, observation (ultrasonography and cardiotocography) and nonsurgical intervention (digitalis).     

First-trimester ultrasonic diagnosis of twin reversed arterial perfusion sequence.

Twin reversed arterial perfusion (TRAP) syndrome sequence is a rare specific anomaly of twin gestation with fused placentae and umbilical anastomosis. This syndrome occurs once in very 35,000-48,000 births and has been described in the second trimester (23-29 weeks of gestation). We report on early sonographic diagnosis (10 and 12 weeks' gestation) of two cases of TRAP sequence, together with their umbilical cord Doppler studies.     

Ultrasound diagnostic features of twin reversed arterial perfusion sequence

Two cases of twin reversed arterial perfusion (TRAP) sequence with relevant ultrasound features that would help an accurate diagnosis are described. Available management options are proposed and discussed.     

产前超声诊断双胎反向动脉灌注综合征

目的 探讨多普勒超声在产前诊断双胎反向动脉灌注综合征(TRAP)中的临床价值,提高对此类罕见畸形的认识. 方法 我院1995年1月至2008年9月产前超声诊断及疑似诊断19例TRAP,比较超声与生后随访或引产后病理结果. 结果 19例TRAP中,无心畸胎(受血儿)均有严重结构畸形,产前超声对胎儿皮肤水肿、脊柱、腹腔结构及下肢显示准确性高;但对头颅发育不良及特别短小的上肢显示困难,颜面部畸形基本上显示不清.泵血儿(供血胎)中死胎及死产16例,存活3例;心功能不全9例.胎儿附属结构特征:(1)存活的无心畸胎均为脐动脉供血,血流方向朝向胎儿体内,与正常胎儿脐动脉血流方向相反;(2)两胎儿脐带胎盘附着处可见大的血管相交通;(3)无心畸胎多为单脐动脉;(4)羊水过多为预后不良征象;(5)单羊膜囊双胎常发生脐带缠绕及打结. 结论 多普勒超声可为评价TRAP血流动力学特征、评估泵血儿心功能、附属物异常及预后提供重要信息,为产前诊断TRAP的首选和重要的诊断方法.     

产前超声诊断双胎反向动脉灌注综合征

目的 探讨多普勒超声在产前诊断双胎反向动脉灌注综合征(TRAP)中的临床价值,提高对此类罕见畸形的认识. 方法 我院1995年1月至2008年9月产前超声诊断及疑似诊断19例TRAP,比较超声与生后随访或引产后病理结果. 结果 19例TRAP中,无心畸胎(受血儿)均有严重结构畸形,产前超声对胎儿皮肤水肿、脊柱、腹腔结构及下肢显示准确性高;但对头颅发育不良及特别短小的上肢显示困难,颜面部畸形基本上显示不清.泵血儿(供血胎)中死胎及死产16例,存活3例;心功能不全9例.胎儿附属结构特征:(1)存活的无心畸胎均为脐动脉供血,血流方向朝向胎儿体内,与正常胎儿脐动脉血流方向相反;(2)两胎儿脐带胎盘附着处可见大的血管相交通;(3)无心畸胎多为单脐动脉;(4)羊水过多为预后不良征象;(5)单羊膜囊双胎常发生脐带缠绕及打结. 结论 多普勒超声可为评价TRAP血流动力学特征、评估泵血儿心功能、附属物异常及预后提供重要信息,为产前诊断TRAP的首选和重要的诊断方法.     

Antenatal diagnosis of twin-reversed arterial perfusion sequence (acardiac amorphous) in a triplet pregnancy: case report

Acardiac twinning is the most extreme form of twin–twin transfusion syndrome occurring in monzygotic twin pregnancies with monochorionic placentation. A case of acardiac amorphous foetus, occurring in association with spontaneously conceived triplet pregnancy, diagnosed on ultrasound in early second trimester is described and its antenatal management and brief review of literature discussed.     

Interstitial laser: a new surgical technique for twin reversed arterial perfusion sequence in early pregnancy

Current treatments for twin reversed arterial perfusion sequence are associated with significant morbidity and most are not feasible in early gestation. We report the use of an interstitial laser in two pregnancies complicated by this sequence at 14 and 15 weeks, respectively. A 600μm laser fibre was introduced via a 17 gauge needle into the abdomen of the perfused twin close to the vitelline artery and umbilical vein, which were occluded by neodymium:yttrium aluminium garnet (Nd:YAG) laser. Both pregnancies continued uneventfully and each resulted in the birth of a healthy baby at term.     

25例双胎反向动脉灌注序列征的产前评估与临床处理

目的 分析双胎反向动脉灌注序列征(twin reversed arterial perfusion sequence,TRAP)的临床特点,探讨其产前评估方法及临床处理.方法 回顾25例TRAP产前诊断及超声检查结果,包括无心胎估重和脐血流、泵血胎心功能及大脑中动脉收缩期峰值流速,分析其临床处理及妊娠结局.采用Fisher精确概率法进行统计学分析.结果 (1)16例泵血胎行羊水染色体核型分析,发现1例嵌合型46,XX[ 36]/46,XY[ 14].(2)根据超声评估,巨大无心胎占87.0％(20/23),86.4％(19/22)的病例两胎脐动脉阻力指数差值≤0.20,提示无心胎血供丰富,66.7％(10/15)的泵血胎出现心功能失代偿,泵血胎大脑中动脉收缩期峰值流速＞1.5中位数的倍数者占75.0％(12/16),提示贫血.(3)血供丰富者发生巨大无心胎的比例(94.7％,18/19)高于血供不丰富者(1/3),差异有统计学意义(Fisher精确概率法,P=0.04).巨大无心胎者泵血胎发生心功能失代偿的比例(83.3％,10/12)高于非巨大无心胎发生心功能失代偿的比例(0/3),差异有统计学意义(Fisher精确概率法,P=0.02).(4)11例首诊后选择引产终止妊娠,14例继续妊娠者泵血胎存活率为64.3％(9/14).继续妊娠者中3例首诊时不伴泵血胎心功能异常的非巨大无心胎选择保守观察,2例足月分娩,1例病情进展而引产;11例泵血胎心功能异常或贫血的巨大无心胎中5例选择保守观察,其中1例流产,3例病情进展(1例引产、2例早产),1例病情稳定至分娩;另外6例选择脐带电凝,5例成功,其中4例泵血胎存活.结论 泵血胎的产前诊断结果、心功能状态、贫血、无心胎发育程度及脐血供是TRAP产前评估的重要指标,应根据产前评估结果对TRAP进行及时处理.     

Treatment of twin reversed arterial perfusion sequence by septostomy and amniodrainage: a case report

Introduction An acardiac fetus is the most severe malformation seen in humans. It is an extremely rare complication, occurring in approximately 1% of all monozygotic twin gestations, with an incidence of about 1 in 35,000 births. This malformation happens as a result of the syndrome of reversed arterial perfusion of the acardiac twin from the other normal fetus (pump twin), due to the presence of arterio-arterial anastomoses in a monochorionic placenta. Several obstetric and perinatal complications have been associated to this anomaly and several treatments have been proposed to reduce the morbimortality of the pump twin. There’s no report in MEDLINE about the treatment of twin gestations with acardiac fetus through septostomy. Case report The present article reports a case of reversed arterial perfusion sequence complicated by polyhydramnios diagnosed at 19th week of pregnancy, treated with septostomy and serial amniodrainage. Discussion This case presented it demonstrate favorable development of the gestation, with labor happening at 35 weeks gestation and pump twin presenting good vitality conditions. In cases with no major factors of bad prognosis, septostomy combined with amniodrainage could be an interesting therapeutic option for a safe and efficacious management of selected cases of TRAP sequence.     

Treatment of twin reversed arterial perfusion sequence with alcohol ablation or bipolar cord coagulation

ObjectiveTo evaluate perinatal outcome in pregnancies complicated by TRAP sequence.MethodsThe perinatal outcomes of 15 TRAP sequence pregnancies referred to Kanuni Sultan Suleyman Research and Teaching Hospital, Turkey, were evaluated. Six cases were treated conservatively. Alcohol ablation and bipolar coagulation were performed in 5 and 4 cases, respectively.ResultsIn 12 cases, there were signs of fetal compromise and acardiac/pump twin abdominal circumference ratio of more than 50%. In 3 cases without intervention, the ratio was less than 50%. Three of the 6 pregnancies treated conservatively resulted in intrauterine death of the pump twin. Alcohol ablation was successful in 3 cases, with delivery of live fetuses at 36–38 weeks, whereas intrauterine death occurred in 1 case and abortion occurred in 1 case. In 2 of the cases involving bipolar cord coagulation, live birth occurred at 39 weeks; preterm premature rupture of membranes and abortion occurred at 18 weeks in 1 case, and pregnancy was terminated in 1 case because of ventriculomegaly.ConclusionConservative therapy is suitable for mild cases of TRAP sequence in which the pump twin dominates. If there are signs of pump twin compromise, alcohol ablation and bipolar cord coagulation can be performed successfully.     

Spontaneous cessation of umbilical blood flow in the acardiac fetus of a twin pregnancy.

The acardiac fetus is a rare entity found only in monozygotic multiple pregnancy. Although the acardiac fetus is non-viable, the perinatal mortality rate for the normal fetus may be as high as 50 per cent, and is usually associated with fetal heart failure and hydrops fetalis, or as the result of prematurity. In this communication, we describe a case of spontaneous cessation of blood flow to an acardiac fetus and discuss the management of this condition with special reference to optimizing the outcome for the normal fetus.     

Twin reversed arterial perfusion sequence: two different heartbeats in one umbilical cord - rare finding in monochorionic twin pregnancy

The development of twin-twin transfusion syndrome complicates 5-35% of twin pregnancies with monochorionic placentation. Acardiac twinning is the most extreme manifestation of pathological vascular anastomoses between twins. An acardiac twin is a rare complication of multifetal pregnancy, reported in the literature with an incidence of 1% in monochorionic twin pregnancies, i.e. 1/35 000 pregnancies, and more than 400 cases have been described. We review the literature on this subject and report a special case of twin reversed arterial perfusion (TRAP) sequence in a twin pregnancy with the rare finding of a functional univentricular circulation pump in the acranius, its antenatal ultrasound diagnosis and postnatal findings. Remarkably, prenatally we could demonstrate two different arterial pulsations in the umbilical cord of the acranius. Etiological hypotheses of the TRAP sequence and new implications for risk-adapted therapeutic options are discussed.     

产前超声诊断多胎妊娠无头无心反向动脉灌注三例

目的 探讨双胎无心反向动脉灌注（twin reversed arterial perfusion TRAP）的产前超声声像图特征。方法 回顾性分析3例产前超声诊断为TRAP的超声图像与随访结果，总结声像图特点。结果 2例产后病检证实为TRAP，1例失访。TRAP的特点是，双胎或三胎中均有一个胎儿无头无心畸形，胸腹腔内没有正常内脏结构，无正常上肢结构，可见下肢及下肢运动。皮肤及皮下组织明显增厚，均为单脐动脉；彩色多普勒显示无心胎儿体内出现没有心脏的血液循环通路；频谱多普勒记录到进人胎儿体内脐血管为动脉频谱，出胎儿腹壁的脐血管为静脉频谱，形成了与正常胎儿灌注方向完全相反的灌注特点。结论 多胎妊娠中（包括双胎和三胎）若有单卵双胎，且其中之一伴有严重畸形、无心脏结构与搏动，彩色多普勒记录到进入无心胎儿体内的脐血管为动脉频谱，出胎儿的血管为静脉频谱，为TRAP的重要声像图特征。