Outcome of Monochorionic Monoamniotic Twin Reversed Arterial Perfusion Sequence Diagnosed in the First Trimester

<b><i>Introduction:</i></b> The aim of this study is to evaluate the outcome of pregnancies complicated by monochorionic monoamniotic twin reversed arterial perfusion sequence (MOMA TRAP) diagnosed in the first trimester. <b><i>Methods:</i></b> All patients diagnosed with MOMA TRAP sequence &#x3c;14.0 weeks of gestation in a 10-year study period were retrospectively analyzed for intrauterine course and outcome. All patients were offered either expectant management or intrauterine intervention. Adverse outcome was defined as either intrauterine death (IUD), neonatal death or preterm birth &#x3c;34.0 weeks of gestation. <b><i>Results:</i></b> In the study period, 17 cases with MOMA TRAP sequence were diagnosed. Of these, 2 couples opted for termination of pregnancy. The remaining 15 were divided into 2 groups depending on the management: group A (<i>n</i> = 8) with expectant management and group B (<i>n</i> = 7) with intrauterine intervention. All fetuses in group A died before 20 weeks. Survival in group B was significantly better with 4/7 (57.1%) life births at a median of 39.6 weeks of gestation (<i>p</i> = 0.0256). The reasons for IUD in the 3 cases in group B were hemodynamic, strangulation, and bleeding complications during intervention. <b><i>Conclusions:</i></b> Intrauterine intervention in MOMA TRAP pregnancies significantly improves neonatal survival, although it is still associated with a substantial risk for IUD by hemodynamic complications or entanglement.

TRAP sequence; case report

TRAP sequence is a syndrome with poor prognosis seen in monochorionic twin pregnancies at the rate of 1/100. There is an acardiac “nonviable” fetus with multiple anomalies in the TRAP sequence and a pump fetus feeding this fetus through vascular anastomoses in the placenta. Mortality for acardiac twins is 100%. The mortality of the pump twin is around 50%, and death may be generally due to high flow rate heart failure and sometimes prematurity caused by polyhydramnios. Here, we presented an acardiac acephalous type TRAP case that applied to the Obstetrics and Gynecology Clinic of Amasya University Sabuncuoğlu Şerefeddin Training and Research Hospital. The case was 30 years old. The patient had the first pregnancy and reached this pregnancy with the IVF method. She did not have any disease. During the measurement of NT, the fetus of acardiac acephalous type was detected. Laser ablation was performed at the outer center at 18 weeks. All subsequent follow-ups were done by our center. While the patient had 39 weeks and 2 days of pregnancy, the pregnancy was terminated by performing cesarean due to primipara breech arrival.

Acardia anceps- A case report

Twin-Reversed Arterial Perfusion(TRAP) sequence or Acardia twin refers to a unique complication of mono-chorionic twin pregnancy in which a twin with an absent or rudimentary non functioning heart (acardiac twin) is perfused by its co-twin (pumping twin) through a large artery to artery placental shunt, often accompanied by a vein to vein shunt. Here we discussed about a clinical case of TRAP sequence came in established preterm labour and its management.

Outcome of TRAP Sequence Treated in the First Trimester – A Ten-Year Single-Center Experience

Purpose To evaluate the outcome of first trimester intervention by intrafetal laser (IFL) in pregnancies complicated by twin reversed arterial perfusion (TRAP). Materials and Methods For a 10-year study period, all patients with TRAP diagnosed < 14.0 weeks of gestation were retrospectively analyzed for intrauterine course and outcome. Monoamniotic pregnancies were excluded. Patients were offered either intervention by IFL in the first trimester, expectant management, or termination of pregnancy (TOP). Adverse outcome was defined as either intrauterine death (IUD), neonatal death, or preterm birth. Results In 45 cases TRAP was diagnosed. 17 monoamniotics were excluded. The cohort was divided into two groups according to management. Group A: 24 cases underwent IFL and group B: 4 cases were managed expectantly. No patient opted for TOP. In group A, 70.8 % of pump twins were born alive, including one preterm delivery, and 29.2 % died within four days after the intervention. All 4 expectantly managed cases in group B had an adverse outcome (1 preterm delivery, 3 IUDs < 15.0 weeks). There were no neonatal deaths. In cases treated by IFL, a comparison of survivors and non-survivors identified no significant differences in gestational age at IFL or any of the assessed biometrical and functional parameters. There was a trend towards better outcome in the second half of the study period. Conclusion IFL in first trimester TRAP sequence is technically feasible but is associated with significant mortality, albeit less than previously reported. No risk stratification is possible using the investigated parameters. However, there seems to be a learning curve.

An incidental rare finding of a TRAP sequence during a caesarean section: A case report

Twin reversed arterial perfusion (TRAP) sequence is an anomaly of monochorionic twin pregnancies where one twin has an absent, non-functioning or rudimentary heart while the other twin may be normal. The condition occurs because of early development of arterio -arterial anastomoses between the umbilical arteries of twin foetuses that share a fused placenta. In this condition, the affected anomalous (acardiac twin) is perfused by the normal twin (pump twin) via an arterio-arterial anastomosis. The affected twin (acardiac twin) presents with malformations such as absent (acradia) or rudimentary heart, underdeveloped or missing head, upper body and limbs. As pump twin has to provide circulation to itself as well as the perfused twin, this increased burden to perfuse acardiac twin increases the risk of developing cardiac failure in pump twin. Here we present such a case of 22-year-old, which was diagnosed per operatively during caesarean section at department of obstetrics & gynecology, Rukshamaniben General Hospital, Ahmedabad.

‘TRAP-ped with an Acardius’: Case Series of Twin Reversed Arterial Perfusion (TRAP) Sequence and Review of Literature

Twin reversed arterial perfusion (TRAP) sequence is a rare but severe condition that affects monochorionic (MC) multifetal pregnancies. In twin pregnancies, it is characterized by a normally developed twin and another twin with missing heart function (acardiac twin or TRAP twin). A variety of risks and complications may affect the normal twin. Management of such pregnancies can be either expectant or interventional. We report four cases of TRAP sequence treated in our institutions and supply an overview on currently existing literature. This case series demonstrates the heterogeneity in manifestations and clinical course of patients affected by this condition. Furthermore, it includes an acardius amorphous of considerable size delivered at 35.6 weeks of gestation.

Conservative management of a case of a cardiac anceps twin reversed arterial perfusion sequence misdiagnosed as vanishing twin: a case report

Twin reversed arterial perfusion (TRAP) sequence is a specific, rare and severe complication of monochorionic multiple pregnancy, which is characterized by one normal fetus (pump twin) and another with no cardiac activity and variable degree of deficient development of the head and upper limbs. The management of these pregnancies are a real challenge due to the parasitic hemodynamic dependence of the acardiac twin on the pump twin. The aim of management is to maximize the chances of survival of the pump twin with some intervention. The preferred management suggested is elective ultrasound-guided laser coagulation or radiofrequency ablation of the umbilical cord vessels at 11-13 weeks when the survival is 70-75%. Delay in intervention until 16-18 weeks is associated with spontaneous cessation of blood flow in the acardiac twin in 60% of cases and in about 50% of these there is death or brain damage in the pump twin. However, pregnancies diagnosed late need to follow a tailored approach with expectant management. The authors report a case of TRAP twin sequence which on ultrasound was diagnosed as a case of vanishing twin at 20 weeks. Subsequently on follow up ultrasound, it was diagnosed as a trap sequence with the pump twin developing polyhydramnios at 30 weeks. She was counselled regarding the prognosis of the pump twin and she opted for conservative management. Weekly ultrasound and color doppler were done. The amniotic fluid index (AFI) decreased gradually at 33 and 35 weeks, there were no signs of congestive cardiac failure of the pump twin on Doppler studies and she had a spontaneous delivery of a healthy male child and an acardiac anceps fetus at 36weeks and 5 days. The perinatal mortality of a pump twin managed conservatively ranges from 35 to 55%. It is essential to diagnose the presence of trap sequence at an early gestational age through improved imaging techniques to plan a timely and effective intervention to salvage most of the pump twins.