Twin Anemia-polycythemia Sequence Research Articles

Fetal and neonatal neuroimaging in twin-twin transfusion syndrome.

To describe the types of brain injury and subsequent neurodevelopmental outcome in fetuses and neonates from pregnancies with twin-twin transfusion syndrome (TTTS). Additionally, to determine risk factors for brain injury and to review the use of neuroimaging modalities in these cases. This was a retrospective cohort study of consecutive TTTS pregnancies treated with laser surgery in a single fetal therapy center between January 2010 and January 2020. The primary outcome was the incidence of brain injury, classified into predefined groups. Secondary outcomes included adverse outcome (perinatal mortality or neurodevelopmental impairment), risk factors for brain injury and the number of magnetic resonance imaging (MRI) scans. Cranial ultrasound was performed in all 466 TTTS pregnancies and in 685/749 (91%) liveborn neonates. MRI was performed in 3% of pregnancies and 4% of neonates. Brain injury was diagnosed in 16/935 (2%) fetuses and 37/685 (5%) neonates and all predefined injury groups were represented. Four fetal and four neonatal cases of cerebellar hemorrhage were detected. Among those with brain injury, perinatal mortality occurred in 11/16 (69%) fetuses and 8/37 (22%) neonates. Follow-up was available for 29/34 (85%) long-term survivors with brain injury and the mean age at follow-up was 46 months. Neurodevelopmental impairment was present in 9/29 (31%) survivors with brain injury. Adverse outcome occurred in 28/53 (53%) TTTS individuals with brain injury. The risk of brain injury was increased after recurrent TTTS/post-laser twin anemia-polycythemia sequence (TAPS) (odds ratio (OR), 3.095 (95% CI, 1.581-6.059); P = 0.001) and lower gestational age at birth (OR per 1-week decrease in gestational age, 1.381 (95% CI, 1.238-1.541); P < 0.001). Based on dedicated neurosonography and limited use of MRI, brain injury was diagnosed in 2% of fetuses and 5% of neonates with TTTS. Adverse outcome was seen in over half of cases with brain injury. Brain injury was related to recurrent TTTS/post-laser TAPS and a lower gestational age at birth. © 2024 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Magnetic resonance imaging of intracranial anomalies in pregnancies complicated by twin anemia-polycythemia sequence

PurposeTo describe fetal brain Magnetic Resonance Imaging (MRI) findings in a large series of monochorionic (MC) pregnancies complicated by Twin Anemia-Polycythemia Sequence (TAPS) prenatally diagnosed, so to characterize the potential intracranial complications associated with this condition, their frequency and potential treatment options.MethodsThis is a retrospective study of MC twin pregnancies complicated by TAPS and undergone fetal MRI in a single institution from 2006 to 2023.MRI control was performed and post-natal ultrasound (US) or MRI were available.Results1250 MC pregnancies were evaluated in our institution. 50 pregnancies (4%) were diagnosed with TAPS, 29 underwent a fetal brain MRI.13/29 pregnancies (44.8%) demonstrated brain findings at MRI in at least a twin. Neuroradiological findings were detected in 14/57 twins (24.6%).We detected four main categories of findings: hemorrhagic lesions, T2-weighted white-matter hyperintensities (WMH), brain edema-swelling and venous congestion. Nineteen findings were present in the anemic and three in the polycythemic twins, with a statistically significant ratio between the two groups (p-value = 0.01).Intrauterine MRI follow-up demonstrated the sequalae of hemorrhagic lesions. A complete regression of brain swelling, veins prominence and T2-WMHs was demonstrated after treatment. Postnatal imaging confirmed prenatal features.ConclusionsOur work demonstrates that TAPS-related MRI anomalies consisted in edematous/hemorrhagic lesions that occur mostly in anemic rather than in polycythemic twins. Fetoscopic laser surgery could have a potential decongestant role.Therefore, prenatal MRI may help in counselling and management in TAPS pregnancies, especially for the planning of therapy and the monitoring of its efficacy.

66 Abnormal TRECs and transient lymphopenia associated with Twin anemia polycythemia sequence

66 Abnormal TRECs and transient lymphopenia associated with Twin anemia polycythemia sequence

Perinatal outcomes of fetoscopic selective laser photocoagulation for spontaneous twin-anemia polycythemia sequence.

Antenatal management of monochorionic pregnancies complicated by twin anemia polycythemia sequence (TAPS) remains sub-optimally defined. Our objective was to evaluate the safety and efficacy of fetoscopic selective laser photocoagulation with respect to fetal and neonatal survival. A case series is reported with patients referred to the Texas Children's Fetal Center for evaluation and management of suspected spontaneous TAPS without concomitant twin-to-twin syndrome from 2014 to 2023. All evaluations were performed by our team and patients with stage II-IV TAPS were offered expectant management, intrauterine transfusion, or laser therapy. Cases of post-laser TAPS were excluded from this study. Pregnancy and neonatal outcomes were obtained from electronic medical records. During a 10-year time period, 18 patients presented to our center for the management of TAPS. Thirteen patients had stage II-IV TAPS (13/18, 72%) and elected to proceed with laser photocoagulation. All procedures were completed, and "solomonization" was performed for 12/13. Normalization of middle cerebral artery Dopplers in both fetuses was noted after all cases. There was one intrauterine fetal death of the 26 viable fetuses after laser treatment, which was complicated by selective growth restriction. Most patients (12/13) were delivered by Cesarean section at a mean gestational age of 29±3weeks. Subsequently, there was one ex-donor neonatal death in an infant who had prenatal hydrops. Overall, 30-day postnatal survival was 24/26 fetuses (92.3%). In the setting of spontaneous TAPS, laser therapy is feasible and appears to be an effective approach with overall favorable perinatal outcomes.

Is There a Cumulative Effect for Congenital Heart Defects in Monochorionic Twins after Assisted Reproduction? - A Retrospective Analysis at a Tertiary Referral Center.

The aim of our study was to compare maternal, chorionicity and neonatal complications in monochorionic (MC) twins between spontaneously conceived (SC) and assisted reproductive technologies (ART) pregnancies. This was a retrospective cohort study between January 2010 to December 2019 at a tertiary referral University center. All consecutive pregnancies with MC twins that delivered at our University hospital were included. Maternal, chorionicity and neonatal complications were recorded and compared between SC and ART pregnancies. 393 MC pregnancies were included for final analysis, including 353 (89.8%) SC and 40 (10.2%) pregnancies conceived after ART. Hypothyroidism was the only maternal condition seen significantly more often in ART pregnancies (35.0% vs 12.5%, p=0.001). There were no significant differences in chorionicity complications, such as twin-twin transfusion syndrome, selective fetal growth restriction and twin anemia-polycythemia sequence (40.0% in ART pregnancies vs 31.6% in SC pregnancies, p=0.291). At least one congenital anomaly in one twin was seen significantly more often in ART pregnancies (18.8% vs 8.1%, p=0.004), especially congenital heart defects (16.3% vs 6.2%, p=0.005). There were no other significant differences in neonatal outcomes between both groups, however, there were non-significant trends in gestational age at delivery (34 weeks in ART pregnancies vs 35 weeks, p=0.078) and birthweight (1951g±747 in ART pregnancies vs 2143g±579, p=0.066). This is the largest cohort study to date comparing maternal, chorionicity and neonatal complications between MC twin pregnancies after ART and after SC. Hypothyroidism was the only maternal condition occurring more frequently in pregnancies conceived after ART. There were no significant differences in chorionicity complications, in contrast to previously reported studies. While MC twins and ART pregnancies per se are known to be at risk for congenital heart defects, there seems to be a cumulative effect in MC pregnancies conceived after ART.

Rare case of postnatal diagnosed twin anemia-polycythemia sequence in mcda twins with normal mca -psv Doppler

Rare case of postnatal diagnosed twin anemia-polycythemia sequence in mcda twins with normal mca -psv Doppler

Predictors of fetal death, neonatal survival and neurological outcomes in severe twin-twin transfusion syndrome treated by laser ablation of placental vessels.

To identify predictors of outcomes in severe twin oligo-polyhydramnios sequence (TOPS) with or without twin anemia-polycythemia sequence (TAPS) and/or selective fetal growth restriction (SFGR) treated by laser ablation of placental vessels (LAPV). Analysis of cases treated from 2011 to 2022. Variables evaluated Prenatal predictors: stages of TOPS, presence of TAPS and/or SFGR; pre-LAPV fetal ultrasound parameters; peri-LAPV variables. Perinatal predictors: GA at birth; birthweight; Apgar scores; transfontanellar ultrasonography (TFUS). fetal death, neonatal survival, infant's neurodevelopment. Binary logistic regression analyses were performed to detect predictors of outcomes. 265 cases were included. Predictors of post-LAPV donor fetus' death were delta EFW (p:0.045) and absent/reverse end-diastolic flow in the umbilical artery (AREDF-UA) (p<0.001). The predictor of post-LAPV recipient fetus' death was hydrops (p:0.009). Predictors of neonatal survival were GA at birth and Apgar scores. Predictors of infant's neurodevelopment were TFUS and pre-LAPV middle cerebral artery Doppler (MCAD) for the donor twin; and pre-LAPV ductus venosus' flow and MCAD for the recipient twin. Prediction of fetal death, neonatal survival and infant's neurodevelopment is possible in cases of TOPS associated or not with SFGR and/or TAPS that were treated by LAPV.

Развитие острой фето-фетальной трансфузии при родоразрешении монохориальных диамниотических двоен

Objective. To determine the incidence and characteristics of acute feto-fetal transfusion (FFT) in patients with an uncomplicated monochorionic diamniotic (MCDA) twin pregnancy who had a vaginal delivery and to compare their perinatal outcomes with those patients who underwent elective cesarean section. Patients and methods. This retrospective study included data on perinatal outcomes of 92 births in patients with MCDA twins delivered at the Maternity Hospital No 17 between 2019 and 2021. All patients were divided into two groups according to the mode of delivery: the study group (n = 49) – vaginal delivery, the control group (n = 43) – elective cesarean section before the onset of labor. Results. No diagnostically significant signs of acute FFT were found among newborns delivered by cesarean section. Acute FFT was detected in four neonates born to two (4%) patients delivered vaginally. These neonates had the Apgar score at 1 minute and 5 minutes greater than 7. Only one of these four neonates required phototherapy for neonatal jaundice caused by polycythemia and transfer to a pediatric hospital for stage 2 neonatal nursing. When comparing perinatal outcomes in patients in both groups delivered after 36 weeks’ gestation, no statistically significant differences in Apgar scores at 1 minute and 5 minutes and differences in hemoglobin levels in newborns were found regardless of delivery. In case of delivery before 36 weeks’ gestation, Apgar scores at 1 minute and 5 minutes were statistically significantly higher in the vaginal delivery group than in the cesarean section group. Conclusion. The data obtained show a low incidence of acute FFT in neonates born through vaginal delivery in an uncomplicated MCDA twin pregnancy and the absence of this complication in newborns delivered by cesarean section. When this specific complication of MCDA twin pregnancy developed among newborns, no perinatal losses were detected, and subsequent postnatal outcomes were favorable. It appears that further studies to clarify the diagnostic criteria and risk factors for the development of acute FFT in labor and the long-term health outcomes for newborns in an uncomplicated MCDA twin pregnancy may reduce the rate of cesarean delivery without worsening perinatal outcomes. Key words: monochorionic twins, acute feto-fetal transfusion, twin-to-twin transfusion syndrome, twin anemia polycythemia sequence

Artery-to-vein anastomoses in unequally divided placentas and their association with birthweight discordance

IntroductionThis study investigated the impact of the shared intertwin circulation in unequally divided monochorionic (MC) placentas on fetal growth. MethodsThis retrospective analysis included color-dyed, unequally shared placentas from two tertiary centers. Exclusions included twin-twin transfusion syndrome, twin anemia polycythemia sequence, and lethal anomalies. Measurement of the external diameters and areas of the artery-to-artery (AA), artery-to-vein (AV), and vein-to-vein (VV) anastomoses was performed. The ratio of the shared circulation (AV ratio) was determined by comparing the areas of the summed venous components of shared AV anastomoses to those in the individual AV anastomoses of the smaller placental part. The birth weight ratio/placental ratio (BWR/PR), total AV size areas and net AV transfusion were calculated. Univariable and multivariable linear regressions were performed to assess the relationship between BWR/PR, the AV ratio, the areas of the different anastomoses and cord insertion discordance. ResultsAmong 352 placentas, 97 % (340) had intertwin AV anastomoses, and 50 % (176) were from pregnancies with selective growth restriction. The AV ratio, AA, VV, total AV areas, and cord insertion discordance negatively correlated with BWR/PR. Multivariable linear regression confirmed the independent negative association between BWR/PR and the AV ratio, suggesting that a larger shared circulation benefits the twin with the smaller placental part. Type III sFGR placentas exhibited the highest AV ratio, resulting in the lowest BWR/PR. DiscussionA larger shared circulation mitigates the impact of an unequally divided placenta on fetal growth. This effect surpasses the influence of AA and VV diameters and is most prominent in Type III sFGR placentas.

Latrogenic twin anemia: polycythemia sequence post-amnioreduction in twin-twin transfusion syndrome

We present a case of Iatrogenic twin anemia–polycythemia sequence (TAPS) post-amnioreduction in twin-twin transfusion syndrome at 32 gestational weeks. Slight middle cerebral artery (MCA) peak systolic velocity (PSV) discrepancy was present 3 days after the amnioreduction, with MCA PSV around 1.5 MoM of the doner and 1.0 MoM of the recipient. Eighteen days after the amnioreduction, though MCA PSV remained stable, placental dichotomy, starry-sky liver of the recipient and small amount of right pleural effusion of donor were noted. TAPS was diagnosed and postnatal examination of the twins and the placenta confirmed it. We conjectured that the decompression of the placenta after the sudden reduction of amniotic fluid volume may cause the patency of the tiny anastomoses, resulting in the TAPS.

SFM Fetal Therapy Practice Guidelines: Fetoscopic Laser Photocoagulation in Monochorionic Twins

AbstractFetoscopic laser coagulation is offered as a method of treatment for twin-to-twin transfusion syndrome or twin anemia polycythemia sequence. It involves laser ablation of intercommunicating superficial blood vessels on the surface of the placenta, under sono-endoscopic control. Preterm labor and preterm prelabor rupture of the membranes are known complications. The results depend on the expertise of the surgeon, location of the placenta, indication for treatment, severity of disease, and growth of babies. The chances of both babies surviving are around 65% and one baby surviving is 85%.

The Current Knowledge of Cerebral Magnetic Resonance Imaging in Monochorionic Twins: A Systematic Review of the Last 20 Years

The distinct placental angioarchitecture in monochorionic (MC) pregnancies increases the risk of complications such as twin–twin transfusion syndrome (TTTS), twin anemia polycythemia sequence (TAPS), and selective fetal growth restriction (sFGR). The aim of this systematic review was to evaluate the incidence, type, and severity of cerebral injury and structural brain development on fetal and/or neonatal cerebral magnetic resonance imaging (MRI) in MC twins with or without complications. Twenty-three studies were included, covering a wide range of complications observed during MC pregnancies, with studies involving sIUFD (n = 12), TTTS (n = 7), mixed complications (n = 2), TAPS (n = 1), and uncomplicated MC pregnancy (n = 1). TAPS and sFGR were largely underrepresented in the current literature. The included studies reported that MC pregnancies with single intrauterine fetal demise (sIUFD) are most at risk for cerebral injury during the fetal period. The overall median incidence of cerebral injury after sIUFD was 28.3% (0–55%). Severe antenatal cerebral injury after sIUFD was detected antenatally in 6.5% (0–36%) of the cases. Three of the included studies described the incidence, type, and severity of cerebral injury on neonatal MRI in MC twins. Structural brain development based on cerebral biometry was only assessed in two studies, revealing significantly smaller biometric measurements of the cerebrum in cases of single sIUFD or smaller twins compared to singleton pregnancies. To enhance our understanding of the potential risks and pathophysiological mechanisms associated with cerebral injury and structural brain development in MC twins, there is a need for future studies and standardized protocols using serial fetal and neonatal MRI imaging in addition to routine ultrasound imaging.

Perinatal outcomes of monochorionic triplet pregnancies: multicenter cohort study.

Monochorionic triplet pregnancies are extremely rare and information on these pregnancies and their complications are limited. We aimed to investigate the risk of early and late pregnancy complications, perinatal outcomes, and the timing and methods of fetal intervention in monochorionic triplet pregnancies. This was a multicenter retrospective cohort study including monochorionic triamniotic (MCTA) triplet pregnancies. The exclusion criteria were twins, or multiple pregnancies with higher order than triplets (e.g. quadruplets, quintuplets), and dichorionic or trichorionic triplet pregnancies. Data on maternal age, mode of conception, diagnosis of major fetal structural anomalies or aneuploidy, gestational age (GA) at diagnosis of anomalies, twin to twin transfusion syndrome (TTTS), twin anemia polycythemia syndrome (TAPS), twin reversed arterial perfusion sequence (TRAP), or selective fetal growth restriction (sFGR) were ascertained from the patient records. Data on antenatal interventions were collected, including selective (fetal) reduction (3 to 2 or 3 to 1), laser surgery, or any active fetal intervention (including amniodrainage). Finally, perinatal outcomes included livebirth, intrauterine demise (IUD), neonatal death (NND), perinatal death (PND) and termination of pregnancy (TOP). Neonatal data such as GA at birth, birthweight, neonatal intensive care unit (NICU) admission, and neonatal morbidity were also collected. In our cohort of MCTA triplet pregnancies (n=153 after excluding early miscarriages, TOP and loss to follow-up), the majority (90%) were managed expectantly. The incidence of fetal abnormalities and TRAP was 13.7% and 5.2%, respectively. The most common antenatal complication related to chorionicity was TTTS, which complicated just over a quarter (27.6%) of the pregnancies, followed by sFGR (16.4%), while TAPS (both spontaneous and post-laser) occurred in only 3.3%; no antenatal complication was recorded in 49.3% of pregnancies. Survival was largely associated with the development of these complications: 85.1%, 100% and 47.6% of pregnancies had at least one surviving newborn in those without antenatal complications, complicated by sFGR, or complicated by TTTS, respectively. The overall rates of preterm birth prior to 28 weeks and prior to 32 weeks' gestation were 14.5% and 49.2%, respectively. MCTA triplet pregnancies represent a challenge in counseling, surveillance and management as monochorionicity-related complications occur in almost half of these pregnancies, which negatively impact their perinatal outcomes. This article is protected by copyright. All rights reserved.

Monochorionic Twins: TTTS, TAPS, and Selective Fetal Growth Restriction.

With an increasing incidence of twin gestations, understanding the inherent risks associated with these pregnancies is essential in modern obstetrics. The unique differences in placentation in monochorionic twins leads to unique complications, including twin-to-twin transfusion syndrome, the twin anemia-polycythemia sequence, and selective fetal growth restriction. Not only does the understanding of the monochorionic placenta lead to an understanding of the pathophysiology of the complications of monochorionic twins, but it also has led to the development of highly effective directed fetal therapy via fetoscopic laser coagulation used in twin-to-twin transfusion syndrome.

Twin anemia polycythemia sequence in discordant dichorionic twins.

A 23-year-old primiparous woman with spontaneous dichorionic pregnancy was diagnosed by early ultrasonography. She developed hypertensive disorder of pregnancy at 27 weeks of gestation. At 29 weeks and 3 days of gestation, she was transferred to our perinatal center due to increasing discrepancy between the fetal weights (fetus A 1203 g, fetus B 989 g). Notably, polyhydramnios-oligohydramnios sequence was not observed. An emergency cesarean section was performed at 31 weeks 1 day of gestation because of elevated liver enzyme levels. Two male neonates were delivered with birth weights of 1413 and 1098 g, respectively. At birth, twin A was peripherally cyanotic with hemoglobin of 26.4 g/dL and a reticulocyte count of 4.1%. He was treated using partial exchange transfusion for polycythemia. Twin B was pale with hemoglobin of 7.8 g/dL and a reticulocyte count of 20.5%; thus, an emergent red blood cell transfusion was performed for anemia. Based on their hematological values, the twins were diagnosed with twin anemia polycythemia sequence (TAPS). A marked difference in the coloration of the maternal surface was observed in the two placentas on a macroscopic examination (Fig. 1); however, no vascular anastomosis was detected during dye studies. Microscopic histopathology revealed two amniotic layers and two chorionic layers, which confirmed dichorionicity. Recent literature reviews reported that twin-to-twin transfusion syndrome (TTTS) or TAPS occurs in dichorionic twin placentas with evidence of vascular anastomoses, although it is extremely rare.1Kanagaretnam D. Nayyar R. Zen M. Twin anemia polycythemia sequence in dichorionic diamniotic twins: a case report and review of the literature.Clin Case Rep. 2021; 9e04184Crossref Scopus (1) Google Scholar, 2Lanna M. Faiola S. Casati D. Rustico M.A. Twin-twin transfusion syndrome in dichorionic twin pregnancy: rare but not impossible.Ultrasound Obstet Gynecol. 2019; 54: 412-418Crossref Scopus (2) Google Scholar, 3Zilliox M. Koch A. Farve R. Sananes N. Unusual twin anemia-polycythemia sequence in a dichorionic diamniotic pregnancy.J Gynecol Obstet Hum Reprod. 2019; 48: 359-361Crossref Scopus (4) Google Scholar Miniscule anastomoses undetectable by a dye study may have been present in our dichorionic twins. Prenatal diagnosis, close monitoring, appropriate early delivery, and postnatal management are necessary to improve the outcomes of TTTS and TAPS. Thus, this report highlights the importance of prenatal recognition and postnatal confirmation of TTTS or TAPS, regardless of chorionicity. S.H. and S.I. drafted the initial manuscript. S.H., S.I. and S.T. treated the patient, and contributed to the acquisition of clinical data and imaging. M.Y. performed pathological evaluation. S. Y. supervised the manuscript. All authors approved the final manuscript. The authors have no conflicts of interest to declare. We thank the patient's parents for their kind cooperation. We also thank Dr. Chizen Tarui, Department of Neonatology, and Dr. Tomoko Kibara and Megumi Kaneko, Department of Obstetrics, in Hyogo Prefectural Kobe Children's Hospital for their support.

Obstetric vascular Doppler velocimetry: clinical applications and overuses.

A safe and non-intrusive assessment of fetal health is not only crucial in low-risk gestations, but it is also the standard of care in high-risk pregnancies. Therefore, measuring blood flow across different vessels with non-invasive ultrasound methods has been accurately and painstakingly studied and published. Amongst these state-of-the-art techniques, umbilical artery (blood flow) Doppler velocimetry (UADV) has allowed for fetal well-being follow-ups and assess uteroplacental function, which obtains a more complete and clearer picture; particularly in regard to complicated pregnancies. Additionally, there are other modalities with diverse clinical applications that have emerged, including their clinical and research utilization in conditions such as fetal growth restriction (FGR), preeclampsia, fetal anemia, monochorionic twins vascular blood flow mismatch such as is in twin-to-twin transfusion syndrome, twin anemia polycythemia sequence, and twin reverse arterial perfusion sequence. Nevertheless, their applications regarding various other maternal-fetal diagnoses in the same way as premature births and/or multiple gestation surveillance have not been reported to hold strong clinical evidence. With that in regard, the purpose of this unique study was to give update of the multiple clinical applications of this very important obstetrical tool. Additionally, to review the pathophysiology as well as revisit their reported significant valid uses and occasional overuses. We also delved into quality control measures as related to the application of Doppler in obstetrics. Lastly, it is essential to look through and reflect on the future developments of this valuable, non-invasive, high-risk marvelous modern device.

An ethical examination of twin anemia polycythemia sequence screening

An ethical examination of twin anemia polycythemia sequence screening

Prenatal Diagnosis of Fetal Heart Failure.

Fetal heart failure (FHF) is a condition of inability of the fetal heart to deliver adequate blood flow for tissue perfusion in various organs, especially the brain, heart, liver and kidneys. FHF is associated with inadequate cardiac output, which is commonly encountered as the final outcome of several disorders and may lead to intrauterine fetal death or severe morbidity. Fetal echocardiography plays an important role in diagnosis of FHF as well as of the underlying causes. The main findings supporting the diagnosis of FHF include various signs of cardiac dysfunction, such as cardiomegaly, poor contractility, low cardiac output, increased central venous pressures, hydropic signs, and the findings of specific underlying disorders. This review will present a summary of the pathophysiology of fetal cardiac failure and practical points in fetal echocardiography for diagnosis of FHF, focusing on essential diagnostic techniques used in daily practice for evaluation of fetal cardiac function, such as myocardial performance index, arterial and systemic venous Doppler waveforms, shortening fraction, and cardiovascular profile score (CVPs), a combination of five echocardiographic markers indicative of fetal cardiovascular health. The common causes of FHF are reviewed and updated in detail, including fetal dysrhythmia, fetal anemia (e.g., alpha-thalassemia, parvovirus B19 infection, and twin anemia-polycythemia sequence), non-anemic volume load (e.g., twin-to-twin transfusion, arteriovenous malformations, and sacrococcygeal teratoma, etc.), increased afterload (intrauterine growth restriction and outflow tract obstruction, such as critical aortic stenosis), intrinsic myocardial disease (cardiomyopathies), congenital heart defects (Ebstein anomaly, hypoplastic heart, pulmonary stenosis with intact interventricular septum, etc.) and external cardiac compression. Understanding the pathophysiology and clinical courses of various etiologies of FHF can help physicians make prenatal diagnoses and serve as a guide for counseling, surveillance and management.

Suspected twin anemia polycythemia sequence in a dichorionic, diamniotic twin pregnancy: a case report

BackgroundTwin anemia polycythemia sequence is a rare complication in monochorionic twin pregnancy.Case presentationWe describe a case of dichorionic twin pregnancy presenting with suspected twin anemia polycythemia sequence. A 31-year-old White female, on her third pregnancy, had a routine ultrasound scan at 12 weeks gestation, which demonstrated a dichorionic twin pregnancy with one placenta located in the anterior wall and the other in the posterior wall of the uterus. At 21 weeks, a scan demonstrated a 24% growth discordance between the two fetuses with normal Doppler studies and amniotic fluid. At 27 weeks, one twin showed signs of anemia and the other polycythemia; the fetal middle cerebral artery peak systolic velocity was high in the anemic fetus and low in the polycythemic twin (1.8 and 0.5 multiples of the median). An intrauterine blood transfusion was carried out and this increased the fetal hemoglobin concentration in the anemic twin from 3.5 to 12.5 g/dL. At 29 weeks, delivery by cesarean section was carried out because of evidence from middle cerebral artery peak systolic velocity of recurrence of anemia in one twin and worsening polycythemia in the co-twin; at birth the hemoglobin concentrations were 5.6 and 24.9 g/dL, respectively. Histopathological examination confirmed dichorionicity with no communicating vessels between the two placentas.ConclusionsThis is the first case of twin anemia polycythemia sequence in a dichorionic, diamniotic twin pregnancy where intrauterine blood transfusion was used to prolong the pregnancy by almost 2 weeks in a “twin anemia polycythemia sequence-like” setting.

Large proximal intertwin vascular anastomoses as a rare cause of twin anaemia-polycythaemia sequence (TAPS): case report

Background: Twin anaemia-polycythaemia sequence (TAPS) is a form of chronic twin-to-twin transfusion syndrome (TTTS) secondary to slow unidirectional blood flow across minuscule arteriovenous (AV) anastomoses. We present a case of presumed TAPS secondary to unusual, large, proximal anastomoses. Case report: Monochorionic diamniotic (MCDA) twins were born at 25+6 weeks gestation following intrauterine fetal demise. Ultrasound scan two weeks beforehand showed mild growth discordance (0.7%) with normal amniotic fluid volumes. At post-mortem, Twin 1 (825g) appeared pale and Twin 2 (770g) plethoric. Placental examination revealed side-by-side, fused cord insertions at the extreme placental edge, with one artery-to-artery (AA) anastomosis close to the cord insertion and one umbilical vein-to-umbilical vein (UV-UV) anastomosis within Twin 1's cord. All chorionic veins drained into Twin 1’s UV proximal to the anastomosis. Discussion: TAPS is characterised by anaemia in the donor twin and polycythaemia in the recipient twin without oligohydramnios or polyhydramnios and is typically caused by very small (<1 mm diameter) AV anastomoses. To our knowledge, this is the first reported case of TAPS associated with large AA and UV-UV anastomoses. The possibility of acute exsanguination from Twin 1 into Twin 2 following the demise of Twin 2 cannot be excluded. Reference 1. Tollenaar LSA, Slaghekke F, Lewi L, et al. Spontaneous twin anemia polycythemia sequence: diagnosis, management, and outcome in an international cohort of 249 cases. Am J Obstet Gynecol 2021; 224: 213.