Radiofrequency Ablation of Umbilical Cord for Reduction of Twin Reversed Arterial Perfusion Sequence: A Case Series

ISUOG Practice Guidelines: role of ultrasound in twin pregnancy.

Twin Reversed Arterial Perfusion Sequence.

Twin reversed arterial perfusion (TRAP) sequence occurs when there is one non-viable twin without cardiac structures and a viable pump twin that perfuses the acardiac mass. This study aims to investigate the management and immediate neonatal outcomes for monochorionic multiple pregnancies complicated by TRAP referred to the NSW Fetal Therapy Centre (NSW FTC). Retrospective cohort study of multiple pregnancies referred to NSW FTC between April 2006 and April 2014, reviewing data for cases of TRAP sequence (n = 19, including two triplet cases) compared to a timeframe matched sample of uncomplicated monochorionic diamniotic (MCDA) twin pregnancies managed in the unit (n = 45). Primary management of the 19 TRAP cases was expectant management in 10 (53%), radiofrequency ablation (RFA) in 6 (32%), and bipolar cord coagulation, amniodrainage and termination of pregnancy in 1 case each. 1 of 6 RFA cases had pump twin demise <1 week post-procedure. Average gestation at birth (35.1 ± 5.0 vs. 35.0 ± 2.8 weeks) and mean birthweight (2157 ± 1019 g vs. 2245 ± 537 g) were similar between TRAP pump fetuses and uncomplicated MCDA cases. Pump twin survival was 81% (twins only) compared to 98% for uncomplicated MCDA twins (P = 0.02), and in 5 of 19 (26%) TRAP pregnancies the pump fetus had a congenital anomaly. Mean gestational age at birth and mean birthweight were similar for both TRAP and uncomplicated MCDA pregnancies. TRAP cases, however, had higher perinatal mortality, and high rates of congenital anomaly. The overall neonatal outcome at NSW FTC for TRAP cases is similar to reported international outcomes.

Background: Twin reversed arterial perfusion (TRAP) sequence is a rare monochorionic twin pregnancy complication. It should be suspected in the first trimester ultrasound, when one fetus has no cardiac activity in a monochorionic pregnancies. Doppler study is essential for early diagnosis of acardiac twin. This manuscrips shows the importance of reassessing cases considered as vanishing twins in early pregnancy, to avoid a late diagnosis of acardiac twin, without timely treatment. Case Summary: In this case, the assumption of death of one fetus in the first trimester, delayed the correct diagnosis of TRAP until 25 weeks, when the case was referred to our unit. We opted conservative management with weekly ultrasound surveillance, looking for features of heart failure in the pump twin. After suspecting fetal anemia, at 32 weeks a healthy baby weighing 2100g was delivered along with a acardiac anceps with 518g. This is a case of expectant management, for lack of another option, with a successful end. Conclusion: Despite twin reversed arterial perfusion (TRAP) sequence being a rare monochorionic twin pregnancies complication, it should be suspected in the first trimester ultrasound, when detected a monochorionic pregnancies and one embryo/fetus has no cardiac activity. Follow up in fetal death of one twin in a monochorionic pregnancies must be done with Doppler to look for acardiac twin. Because pump twin may develop a high-output cardiac failure and intrauterine fetal demise, for continuing pregnancies without poor prognostic criteria, it is important to maintain weekly ultrasound surveillance, with attention to the intervention criterias.

Guideline No. 440: Management of Monochorionic Twin Pregnancies

Objectives: Selective fetal reduction in monochorionic (MC) pregnancies requires vaso-occlusive procedures to ablate umbilical cord blood flow to achieve asystole of the targeted fetus. We describe the perinatal outcome of a large series of MC pregnancies following radiofrequency ablation (RFA). Methods: This was a prospective study at Queen Charlotte’s Hospital, London of all cases of selective fetal reduction in MC pregnancies using RFA between Jan 2008 and Dec 2011. Indications for fetal reduction included discordant structural anomaly, TRAP sequence, discordant aneuploidy, twin to twin transfusion syndrome, multifetal reduction (MFPR) in triplets or higher order MC pregnancies or fetal growth restriction (FGR). Outcomes investigated were: rupture of membranes (ROM) or miscarriage within 2 weeks of the procedure, preterm delivery, co-twin demise, brain injury, fetal and neonatal death. Statistics were calculated with SPSSv.19. Results: 84 cases of RFA were performed (31 for structural anomaly, 9 for TRAP, 20 for TTTS, 2 for aneuploidy, 11 for MFPR, 11 for FGR). The median gestation at RFA was 17.5 weeks (range 12.1–27.6 weeks). The overall live birth rate was 82%. PPROM and/or miscarriage within 2 weeks occurred in 3% of cases respectively. Co-twin IUD occurred in 13% of cases. The median gestation at delivery was 35 weeks (Range 14–41 weeks). The preterm (<37 weeks) live birth rate was 45%. The incidence of brain injury following the RFA was 4.5%. Neonatal death occurred in 1.2% of cases. The incidence of co-twin demise appeared greatest (19.2%) when the RFA was performed before 16 weeks compared to after 16 weeks (13.9%), although this did not reach significance (P = 0.082). There were no maternal complications. Conclusions: RFA is a safe technique for selective reduction in MC pregnancies and can be performed much earlier compared with other methods. The risk of co-twin demise appears greatest before 16 weeks gestation.

Objectives: Selective fetal reduction in monochorionic (MC) pregnancies requires vaso-occlusive procedures to ablate umbilical cord blood flow to achieve asystole of the targeted fetus. We describe the perinatal outcome of a large series of MC pregnancies following radiofrequency ablation (RFA). Methods: This was a prospective study at Queen Charlotte’s Hospital, London of all cases of selective fetal reduction in MC pregnancies using RFA between Jan 2008 and Dec 2011. Indications for fetal reduction included discordant structural anomaly, TRAP sequence, discordant aneuploidy, twin to twin transfusion syndrome, multifetal reduction (MFPR) in triplets or higher order MC pregnancies or fetal growth restriction (FGR). Outcomes investigated were: rupture of membranes (ROM) or miscarriage within 2 weeks of the procedure, preterm delivery, co-twin demise, brain injury, fetal and neonatal death. Statistics were calculated with SPSSv.19. Results: 84 cases of RFA were performed (31 for structural anomaly, 9 for TRAP, 20 for TTTS, 2 for aneuploidy, 11 for MFPR, 11 for FGR). The median gestation at RFA was 17.5 weeks (range 12.1–27.6 weeks). The overall live birth rate was 82%. PPROM and/or miscarriage within 2 weeks occurred in 3% of cases respectively. Co-twin IUD occurred in 13% of cases. The median gestation at delivery was 35 weeks (Range 14–41 weeks). The preterm (<37 weeks) live birth rate was 45%. The incidence of brain injury following the RFA was 4.5%. Neonatal death occurred in 1.2% of cases. The incidence of co-twin demise appeared greatest (19.2%) when the RFA was performed before 16 weeks compared to after 16 weeks (13.9%), although this did not reach significance (P = 0.082). There were no maternal complications. Conclusions: RFA is a safe technique for selective reduction in MC pregnancies and can be performed much earlier compared with other methods. The risk of co-twin demise appears greatest before 16 weeks gestation.

To report the pregnancy outcomes of patients with twin reversed arterial perfusion (TRAP) sequence treated by radiofrequency ablation (RFA). This was a retrospective study of TRAP sequences treated in a single center between March 2002 and February 2015. Forty patients underwent RFA with expandable tines through a multistep coagulation method between 15 and 26 gestational weeks. The primary outcome was neonatal survival to discharge. The overall survival of the pump twin was 85%. The survival rates in monochorionic-monoamniotic (MCMA) pregnancies and monochorionic-diamniotic pregnancies were 66.7% (4/6) and 87.9% (29/33), respectively. One triplet was treated successfully and delivered at 36 weeks of gestation. One of 35 live births (2.9%) had preterm premature rupture of membranes less than 34 weeks, resulting in infant death. In five intrauterine pump twin deaths, two cases were MCMA twins with cord entanglement, and three cases were MCDA twins with acardius anceps. Our study supports the effectiveness of RFA for TRAP sequence after 15 weeks of gestation. The presence of MCMA twins or acardius anceps is associated with a high risk of pump twin death after RFA. © 2016 John Wiley & Sons, Ltd.

Background: Twin reversed arterial perfusion (TRAP) sequence is a rare anomaly of monochorionic twins involving artery-to-artery anastomoses resulting in a structurally normal “pump” twin that provides circulation to an acardiac twin in a retrograde fashion. Case: Herein we report a rare case of a triplet gestation (TrGA) consisting of two conjoined acardiac TRAP recipients and one surviving normal pump fetus. The TRAP recipients were discordant for their anomalies. We know of only three similar case reports from the literature. Conclusion: Characteristic ultrasound findings allow for the prenatal diagnosis of TRAP sequence and may allow prompt and appropriate treatment to improve the outcome of the pump twin.

Twin reversed arterial perfusion (TRAP) sequence is an uncommon disease affecting monochorionic twin pregnancies. The diagnosis can be made by ultrasound allowing to plan optimal antenatal management. An electronic search was conducted from inception to July 2024 to systematically evaluate and compare the outcomes of different intrauterine interventions in this condition. Eighty-two studies were included, and 859 women with a prenatal ultrasound diagnosis of TRAP sequence with a total of 1763 fetuses were studied. The mean maternal age was 24.2years (range 19-40) and the mean gestational age at diagnosis was 19.6weeks (range 10-32). A total of 792 pregnancies were reported in which a fetal intervention was performed over the past 35years. The mean gestational age at fetal intervention was 22.1weeks (range 11-32). The two most frequent fetal interventions were radiofrequency ablation, performed in 293 cases and laser umbilical cord coagulation in 140 cases. Overall, 684 out of 828 non-acardiac fetuses following fetal intervention survived (82.6%) compared with 49 out of 76 (64.5%) non-acardiac fetuses in pregnancies managed expectantly (p=0.0001). A higher survival rate was seen in fetuses undergoing umbilical cord ligation (100%) although this procedure was performed in only 8 women. Survival rates were 88.9%, 79.9%, 78.9% and 77.9% for monopolar coagulation of the umbilical cord, laser coagulation of the umbilical cord, fetoscopic laser ablation of placental anastomoses and radiofrequency ablation, respectively. Our results show that the survival rate is higher in patients with TRAP who have a prenatal intervention compared with those who have prenatal expectant management. The survival rate varies depending on the modality used for the prenatal intervention. Future studies are necessary to investigate the impact of the gestational age at the time of the procedure on the survival rate depending on the prenatal therapeutic modality.

Twin reversed arterial perfusion sequence managed by bipolar cord coagulation and amniopatch: Case report.

Efficacy of radiofrequency ablation for twin-reversed arterial perfusion sequence

A twin-to-twin transfusion syndrome was diagnosed in a monochorionic-diamniotic pregnancy at 18 weeks' gestation without any malformation, especially heart defect. In spite of the aggressive treatment (serial amnioreduction, digoxin treatment) the donor twin died at 25 weeks and twin reversed arterial perfusion (TRAP) sequence developed and was documented by Doppler ultrasound. In the TRAP-twin, the route of the reversed blood flow from the umbilical arteries was as follows: descending aorta, aortic arch, ascending aorta, aortic valve, left ventricle, mitral valve, left atrium, foramen ovale, right atrium, inferior vena cava, ductus venosus; and back to the placenta through the umbilical vein. After a 12-h observation period the twin reversed arterial perfusion sequence disappeared. During this period ultrasound and fetal blood sampling revealed no sign of fetal anemia or disseminated intravascular coagulation in the surviving twin. Based on our observations, we propose, that the death of one of the twins in monochorionic pregnancy can result in twin reversed arterial perfusion sequence, which is an ultimately rare phenomenon in the second trimester. To our knowledge, this is the first reported case of twin reversed arterial perfusion sequence subsequent to the intrauterine demise of one twin in twin-to-twin transfusion syndrome in which the TRAP-twin had no cardiac malformation.

Midtrimester transvaginal ultrasound cervical length screening for spontaneous preterm birth in diamniotic twin pregnancies according to chorionicity.

428: Midtrimester transvaginal ultrasound cervical length in diamniotic twin pregnancies according to chorionicity