Pump Twin Research Articles

Cord occlusion in twin reversed arterial perfusion sequence: a retrospective study of laser photocoagulation vs radiofrequency ablation.

Twin reversed arterial perfusion (TRAP) sequence is a rare condition complicating monozygotic multiple gestations. Prenatal management via umbilical cord occlusion (UCO) of the anomalous twin has been shown to improve pump twin survival. We compared outcomes of gestations with high-risk TRAP sequence treated with mid-trimester UCO using laser photocoagulation vs radiofrequency ablation (RFA). This is a retrospective, single-center, cohort study of all patients with high-risk TRAP sequence who underwent UCO from 2006-2023. High-risk criteria were defined as follows: larger abdominal circumference of the anomalous twin, polyhydramnios, critically abnormal Doppler waveforms in the pump twin, hydrops in the pump twin, and/or monoamniotic twins. The primary outcome was 30-day survival of the pump twin. The 74 patients were divided equally between the laser and RFA groups. For the 2 groups, mean gestational age (GA) at UCO (20.5 ± 2.3 vs 20.7 ± 3.1 weeks, P=.987) and mean GA at delivery (35.2 ± 4.6 vs 34.5 ± 5.7 weeks, P=.812) were similar. The 30-day neonatal survival rate did not differ (91.9% [34/37] vs 89.2% [33/37], OR: 1.37 [0.29-6.61], P=.692). No difference in 30-day neonatal survival was identified in patients with high-risk TRAP sequence who underwent mid-trimester UCO by laser vs RFA.

Twin reversed arterial perfusion sequence in monochorionic diamniotic pregnancy: A rare occurrence

Twin reversed arterial perfusion is a rare complication occurring in monochorionic multifetal pregnancies. This condition is characterized by a malformed fetus being perfused by a normal twin through an artery-to-artery anastomosis in the reverse direction. Herein, we report a case of a multigravida female with a twin pregnancy at 27 weeks 5 days of gestation referred in view of twin pregnancy with the intra-uterine demise of one twin. Gray scale and color Doppler imaging revealed a monochorionic diamniotic pregnancy with a viable, normal twin, and an amorphously developed acardiac twin. The patient was monitored with weekly ultrasonography, echocardiography, and Doppler ultrasound examination to ascertain the well-being of the pump twin. She delivered a normal live baby at term and an acardius acephalus fetus. The perinatal mortality of the pump twin is significantly high. Therefore, it is necessary to diagnose this entity at an early gestational age through improved imaging techniques, so that timely intervention can be planned.

Fetal magnetic resonance imaging, ultrasound, and echocardiography findings in twin reversed arterial perfusion sequence.

Twin reversed arterial perfusion (TRAP) sequence is a rare complication of monochorionic multiple gestation pregnancies, in which the pump twin provides hemodynamic support to a nonviable co-twin (acardius). Fetal magnetic resonance imaging (MRI) is used to detect pump twin abnormalities, particularly brain ischemia, prior to fetal intervention to interrupt umbilical blood flow to the acardius. To summarize the imaging findings of TRAP sequence pregnancies in a large series. A single-center retrospective review was performed of all TRAP sequence pregnancies referred for fetal MRI (2004-2021). Fetal MRI, ultrasound, and echocardiography data were collected. Eighty-eight TRAP sequence pregnancies with MRI were included (mean gestational age, 19.8±2.8 weeks). Demise of the pump twin was noted in two pregnancies at the time of MRI. By MRI, 12% (10/86) of live pump twins had abnormalities, including 3% (3/86) with brain abnormalities and 9% (8/86) with extra-cranial abnormalities. By echocardiography, 7% (6/86) of pump twins had structural cardiac abnormalities. Three acardius morphological subtypes were identified by MRI: acephalus (55%, 48/88), anceps (39%, 34/88), and amorphous (7%, 6/88). The mean ultrasound acardiustopump twin ratioA/Pratio, calculated for each twin pair as the ratio of the acardius trunk (and head, if present) plus limb volume to the pump twin estimated fetal weight) differed among the three acardius subtypes (P=.03). The mean A/P ratio moderately correlated with pump twin cardiothoracic ratio and combined cardiac output (Pearson's r=0.45 and 0.48, respectively, both P<.001). Fetal MRI of TRAP sequence pregnancies found anomalies in a substantial number of pump twins. The three acardius subtypes differed in A/P ratio, which moderately correlated with the pump twin cardiothoracic ratio and combined cardiac output.

Twin reverse arterial perfusion sequence

Twin Reverse Arterial Perfusion Sequence (TRAP) is a rare condition specific to identical twins. Overall, TRAP affects around 1% of all monozygotic twins, with 75% occurring in monochorionic-biamniotic twins and the remaining 25% in monoamniotic twins. TRAP is characterized by a normal-appearing pump twin supporting a dysmorphic acardiac twin through aberrant arterio-arterial anastomoses in the shared single placenta.

SFM Fetal Therapy Practice Guidelines: Bipolar Cord Coagulation

AbstractBipolar cord coagulation is modality available for the treatment of monochorionic diamniotic twins with any one of the following indications: discordant anomalous fetus, severe selective Intrauterine growth restriction (IUGR) (type 2 and type 3) in very preterm and premature fetuses, and selected cases of twin-twin transfusion syndrome when LASER photocoagulation is not feasible. Twin reversed arterial perfusion sequence with polyhydramnios and cardiac overload in pump twin, Multifetal reduction involving MCDA pair.

Twin Reversed Arterial Perfusion Sequence: A Case Report and Literature Review

Twin reversed arterial perfusion sequence (TRAPS) is one of the complications of monochorionic twin gestation. It is characterised by large intertwined arterial-arterial anastomosis in which blood flows from one twin (pump twin) to the other twin (perfused twin) in a retrograde pattern.&#x0D; We report a case of monochorionic diamniotic twin gestation complicated by TRAPS in a 38-year-old G4P3 trader who was referred to the antenatal clinic of Rivers State University Teaching Hospital on account of unusual abdominal distension of one-week duration at 31 weeks gestational age. Ultrasound scan done at presentation showed a monochorionic diamniotic twin with the first twin in a transverse lie with an estimated foetal weight of 1.7kg, foetal heart rate of 150beats per minute, and Twin 2, had no foetal head, no cardiac pulsation with significant tissue swelling. A diagnosis of TRAPS was made for which she was admitted and delivered by emergency caesarean section. The pump twin was admitted into the Special Care Baby Unit (SCBU) and succumbed to cardiac failure 24 hours after delivery.&#x0D; Monochorionic pregnancy complicated by TRAPS is associated with poor foetal outcomes. Early diagnosis and adequate management will enhance clinical outcomes. The diagnosis of TRAPS requires a high index of suspicion. Clinicians and radiologists need to be aware of the features in order to make prompt diagnosis and take appropriate action which may include early referral to the fetal medicine unit for appropriate intervention and improved outcome for the pump twin.

Twin reverse arterial perfusion sequence: A case report and literature review

Twin reverse arterial perfusion sequence (TRAPS) is one of the complications of monochorionic twin gestation. It is characterised by large intertwined arterial-arterial anastomosis in which blood flows from one twin (pump twin) to the other twin (perfused twin) In a retrograde pattern. We report a case of monochorionic diamniotic twin gestation complicated by TRAPS in a 38-year-old G4P3 trader who was referred to the antenatal clinic of Rivers State University Teaching Hospital on account of unusual abdominal distension of one-week duration at 31 weeks gestational age. Ultrasound scan done at presentation showed a monochorionic diamniotic twin with the first twin in a transverse lie with an estimated foetal weight of 1.7kg, foetal heart rate of 150 beats per minute, and Twin 2, had no foetal head, no cardiac pulsation with significant tissue swelling. A diagnosis of TRAPS was made for which she was admitted and delivered by emergency caesarean section. The pump twin was admitted into the Special Care Baby Unit (SCBU) And succumbed to cardiac failure 24 hours after delivery

Outcome of Monochorionic Diamniotic Twins with Twin Reversed Arterial Perfusion Sequence: Interstitial Laser versus Endoscopic Cord Occlusion.

Twin reversed arterial perfusion sequence (TRAP) is a rare complication of monochorionic twins (MC). This study aimed to describe and compare the short- and long-term outcomes of MC pregnancies with the TRAP sequence treated with two different techniques: interstitial fetal laser (IFL) (n = 22) versus endoscopic cord occlusion (CO) (n = 24). The study population included 46 MC pregnancies with TRAP. Pregnancy loss within 2 weeks after the procedure occurred in 27% of cases (6/22) in the group treated with IFL and in 8% of cases (2/24) in the group treated with CO. The survival rate of the pump twin was 73% (16/22) in the IFL group and 83% (20/24) in the group treated with CO. The median gestational age at birth was 38 weeks in the group treated with IFL and 35 weeks in the group treated with CO. The rate of preterm birth before 34 weeks was 12.5% (2/16) in the group treated with IFL and 32% (7/22) in the group treated with CO. In the group treated with IFL, there were no cases of neurological disabilities reported by the parents compared to three cases in the CO group. IFL is associated with a higher risk of early pregnancy loss; however, if the pregnancy progresses, it is associated with lower risks of preterm birth and neurological disabilities in the survivors.

The Management of Acardiac Twinning: Twin Reverse Arterial Perfusion Sequence – An International Survey

Introduction: The optimal approach and therapy method for the acardiac twin with a reverse arterial perfusion sequence has not yet been established. The aim of this study was to determine the clinical practice patterns among international fetal therapy units in their management of these cases. Methods: A survey was sent to fetal centers across the world via email between December 2020 and December 2021. Results: Responses were obtained from 77% contacted centers. The most frequent ultrasound variables used in the evaluation of twin reverse arterial perfusion sequence include echocardiographic assessment of the pump twin and umbilical artery Doppler waveforms in the acardiac and pump twins, in 90% and 80% of the centers, respectively. Most centers in Europe and Latin America propose an in utero intervention in all cases. Most centers in Europe and Latin America prefer interstitial laser ablation, whereas radiofrequency ablation (RFA) is preferred in North America. The earliest gestational age for an intervention is on mean 13 weeks in Europe, which is earlier than the other geographic areas (p = 0.001). Conclusions: Most centers agreed that antenatal evaluation should include echocardiography along with the UA Doppler waveform measurements, and the most frequently used interventions were interstitial laser ablation or RFA at a median between 14 and 26 weeks.

Twin reverse arterial perfusion: Timing of intervention.

Twin reverse arterial perfusion (TRAP) sequence is a severe anomaly in monochorionic twins where one twin has profound corporeal underdevelopment and acardia. The normal "pump" co-twin provides blood flow to the acardiac twin through placental anastomoses which may lead to cardiac failure and pump twin demise as well as preterm delivery from severe polyhydramnios. Treatments include radiofrequency ablation, bipolar cord coagulation, and intrafetal laser with each aimed at occluding blood flow to the acardiac twin. However, none of these modalities has proven superior in terms of either pump twin survival or minimization of complications, including preterm premature rupture of membranes, preterm birth, or unexpected co-twin demise. The optimal timing of treatment is also unknown, without clear indications for intervention versus expectant management. Very early treatment of TRAP (i.e., <16 weeks) has been proposed to reduce first-trimester demise; however, this approach remains experimental. Further investigation is required to determine the best treatment and timing of intervention for TRAP.

Twin Reversed Arterial Perfusion Sequence: Prenatal Diagnosis and Treatment

Abstract Twin reversed arterial perfusion sequence, a severe and unique complication of monochorionic multiple pregnancy, is characterized by vascular anastomosis and abnormal or absent cardiac development in the twins. This article reviewed its pathogenesis, prenatal ultrasound diagnosis, and management. The pump twin’s chances for survival can be maximized by proper management. The optimal timing of the interventions remains a debate, although the latest studies encourage early intervention, i.e., in the first trimester. The most preferred approach is to interrupt the vascular supply to the acardius, such as through ultrasound-guided laser coagulation and radiofrequency ablation of the intrafetal vessels.

Ultrasound assessment of twin reversed arterial perfusion sequence for the prediction of adverse pregnancy outcomes in the first trimester.

To investigate twin reversed arterial perfusion (TRAP) sequence for the prediction of TRAP-related adverse pregnancy outcomes at the gestational age of 11-14weeks. Pregnant women in the first trimester diagnosed with TRAP were recruited at West China Second University Hospital from January 2015 to June 2018. Systematic screening for the pump twin's crown-rump length (CRL) and acardiac twin's upper pole-rump length (URL) was conducted using ultrasonic detection. The (CRL- URL)/CRL and URL/CRL ratios were used to assess the pregnancy outcomes for the pump twin. Twenty-one pregnant women aged 21-39years with a gestation of 11-14weeks were recruited. TRAP was diagnosed on average(±standard deviation (SD)) at pregnancy week 13.1±0.18. The pump twins' mean(±SD) CRL was 6.65±1.1cm. The incidence of intrauterine death for the pump twins was 19.0% (n=4), the miscarriage rate was 14.3% (n=3), and the live birth rate was 66.7% (n=14). The (CRL- URL)/CRL ratios between the nonsurvival (intrauterine death and miscarriage) and survival groups significantly differed (0.33±0.08vs. 0.58±0.08, p<0.05). Similarly, the URL/CRL ratios between the nonsurvival and survival groups significantly differed (0.67±0.08vs. 0.42±0.08, p<0.05). The (CRL- URL)/CRL and URL/CRL ratios were valuable indicators for determining pregnancy outcomes of pump twins with TRAP at an early gestational age.

Diagnosis and Management of Twin Reversed Arterial Perfusion Sequence at the Korle Bu Teaching Hospital, Ghana

Twin Reversed Arterial Perfusion (TRAP) sequence is a rare complication of twin gestation unique to monochorionic twins, reported to occur in about 1% of all monochorionic pregnancies. In this condition, an acardiac twin, with an absent or non-functioning heart, is perfused by its co-twin (referred to as the “pump” twin) via placental anastomoses. It is associated with a high mortality for the pump twin without intervention. We report two cases of TRAP sequence diagnosed prenatally by ultrasound at the Korle Bu Teaching Hospital. We describe how this rare anomaly can be diagnosed and managed successfully even in a low resource setting to yield good perinatal outcomes.

A CASE OF TRAP SEQUENCE (ACARDIAC TWIN) TREATMENT WITH CONSERVATIVELY

TRAP sequence (twin reversed arterial perfusion) is a complication with a poor prognosis, seen only in monochorionic twin pregnancies, known as acardiac twin formation1. In the very early stages of the formation periods of twin pregnancies, as a result of the single formation of the placenta and the defective formation of the cord vessels of the second baby (acardiac twin), the heart and accordingly the brain development cannot occur in the baby with placenta abnormalities; but other parts of the body can develop in different combinations. Therefore, the second baby can develop from a separate creature to the other baby as a parasite. The normal twin, is known as the pump twin and provides the blood circulation of the acardiac twin. These inter twin anastomoses lead to circulatory confusion, the reverse circulatory morphogenesis interrupted and acardiac twinning occurs2. As the gestational week progresses, the baby grows and develops and this development is accompanied by other parasitic baby. Thus, the baby maintains the blood circulation of the parasitic baby, which is growing both with itself and with her/himself. If the mass development of the other parasitic structure continues in parallel, the heart, which tries to maintain the circulation, may not be able to fulfill this task after a while and fall into failure, and even a healthy baby may be lost for this reason3. This case is presented because the patient had a healthy twin who was born due to the onset of preterm labor that was not terminated at the request of the family, and the other twin with acardiac anencephaly.

Use of holmium laser for umbilical cord transection in a monoamniotic pregnancy threatened by an acardiac co-twin: a case report

BackgroundTwin reversed arterial perfusion sequence is a rare complication of monochorionic multifetal pregnancies. In this syndrome, the acardiac twin has a nonfunctional heart, while the other twin, the pump twin, has normal development. The pump twin perfuses the acardiac twin and is therefore at risk for cardiac decompensation. In monoamniotic cases, the normal co-twin is also at risk of sudden death due to cord entanglement. Treatment consists of coagulation and transection of the acardiac’s umbilical cord. We report the first intrauterine use in pregnancy of a Ho:yttrium aluminum garnet laser to safely and successfully transect the umbilical cord after Nd:yttrium aluminum garnet coagulation.Case presentationA 30-year-old Caucasian woman was referred to our fetal–maternal medicine unit at 9 weeks gestation with a monochorionic–monoamniotic twin pregnancy complicated by an acardiac twin. After counseling, she opted for an elective intervention to minimize the risks to the pump twin. At 16 weeks, fetoscopy was performed using a single 2-mm entry port. Through this port, a 1.0-mm fetoscope and a 0.365-mm laser fiber were introduced. Under fetoscopic sight and ultrasound (Doppler) guidance, the umbilical cord of the acardiac twin was first coagulated by laser energy using a Nd:yttrium aluminum garnet laser and then, using the same fiber, transected using a Ho:yttrium aluminum garnet laser. The patient underwent cesarean section at 38 weeks and delivered a healthy baby.ConclusionsWe present the first report on intrauterine use of an Ho:yttrium aluminum garnet laser in human pregnancy. Ho:yttrium aluminum garnet laser energy can be successfully and safely used for umbilical cord transection and carries fewer risks than other methods of transection.

Doppler Waveform Analysis of Intertwin Venous Blood Flow in Twin Reversed Arterial Perfusion (TRAP) Sequence with a Rudimentary Heart.

Twin reversed arterial perfusion (TRAP) sequence is a rare anomaly in 1% of monochorionic twin pregnancies. Few TRAP sequence cases have a rudimentary heart with cardiac motion in the acardiac twins. Herein, we investigated the venous Doppler waveform in two cases of TRAP sequence with a rudimentary heart with cardiac motion in the acardiac twin. Although both cases had veno-venous anastomoses, the venous Doppler waveforms of the umbilical vein differed. A comparison of the characteristics of the cases indicated that the existence of a ductus venosus, or greater heart pulse power, in the acardiac twin might impact the venous Doppler waveform in the pump twin.

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

Introduction and importanceTwin Reversed Arterial Perfusion (TRAP) Sequence is a rare condition that occurs in monochorionic twin pregnancies, resulting in the coexistence of a normal “pump” twin and an acardiac twin. Indonesia is implementing fetal therapy centers that are starting to treat fetal cases such as TRAP Sequence.Case presentationAn 18 years old pregnant woman with monochorionic diamniotic pregnancy was detected by ultrasonographic examination. A live fetus with normal fetal heart rate estimated fetal weight was 661 g, and consistent with 25 w gestational age. Additionally, an acardiac twin with polyhydramnios and EFW of 1829 g. Bipolar cord coagulation, amniopatch, and amnioinfusion were performed. The patient's condition was stable and managed closely.Clinical discussionThis is the first procedure reported in Indonesia for TRAP sequence case. It reduces cardiac strain on the pump twin and increases the chance of survival.ConclusionThe patient was diagnosed with TRAP Sequence and bipolar cord coagulation to interrupt blood supply to the non-viable twin, amniopatch with autologous platelet concentrate followed by cryoprecipitate amnioinfusion were reported for the first time in Indonesia.

Twin Reversed Arterial Perfusion Sequence.

Twin Reversed Arterial Perfusion Sequence.

Hypothesized pathogenesis of acardius acephalus, acormus, amorphus, anceps, acardiac edema, single umbilical artery, and pump twin risk prediction.

BackgroundAcardiac twinning complicates monochorionic twin pregnancies in ≈2.6%, in which arterioarterial (AA) and venovenous placental anastomoses cause a reverse circulation between prepump and preacardiac embryos and cessation of cardiac function in the preacardiac. Literature suggested four acardiac body morphologies in which select (groups of) organs fail to develop, deteriorate, or become abnormal: acephalus (≈64%, [almost] no head, part of body, legs), amorphus (≈22%, amorphous tissue lump), anceps (≈10%, cranial bones, well‐developed), and acormus (≈4%, head only). We sought to develop hypotheses that could explain acardiac pathogenesis, its progression, and develop methods for clinical testing.MethodsWe used qualitatively described pathophysiology during development, including twin‐specific AA and Hyrtl's anastomoses, the short umbilical cord syndrome, high capillary permeability, properties of spontaneous aborted embryos, and Pump/Acardiac umbilical venous diameter (UVD) ratios.ResultsWe propose that each body morphology has a specific pathophysiologic pathway. An acephalus acardius may be larger than an anceps, verifiable from UVD ratio measurements. A single umbilical artery develops when one artery, unconnected to the AA, vanishes due to flow reduction by Hyrtl's anastomotic resistance. Acardiac edema may result from acardiac body hypoxemia combined with physiological high fetal capillary permeability, high interstitial compliance and low albumin synthesis. Morphological changes may occur after acardiac onset. Pump twin risk follows from UVD ratios.ConclusionOur suggested outcomes agree reasonably well with reported onset, incidence, and progression of acardiac morphologies. Guidance for clinical prediction and testing requires ultrasound anatomy/circulation study, from the first trimester onward.

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.