Incidence, prognosis, and perinatal outcomes of and risk factors for severe twin–twin transfusion syndrome with right ventricular outflow tract obstruction in the recipient twin after fetoscopic laser photocoagulation

Atypical twin-to-twin transfusion syndrome case managed in a single centre in Indonesia with fetoscopic laser photocoagulation and amniopatch: 'Case Report'

Introduction and importance

The diagnostic criteria for Quintero staging in twin-to-twin transfusion syndrome (TTTS) are not applicable in all cases of TTTS, such as those in which the symptoms overlap with other monochorionic twin complications such as selective intrauterine growth restriction (sIUGR).

Case presentation

A 25-year-old woman, G1P0A0, at 22-24 weeks' gestational age was diagnosed with TTTS, with no outstanding history of medication use during pregnancy, and no family history of genetic disorder or twin pregnancy. In the donor twin, persistently absent end-diastolic flow in the umbilical artery was observed using Doppler velocimetry. Polyhydramnios was observed in the recipient twins. The fetal weight discordance between the twins was 39%. After 2 weeks of follow-up, the authors performed fetoscopic laser photocoagulation and successfully ablated five vascular anastomoses and amnioreduction by 2.5 l. Five days after the laser surgery, the patient developed amniotic fluid leakage, and an amniopatch was performed. The authors did the caesarean section at 34 weeks because of severe preeclampsia, the donor and recipient birth weights were 1,120 g and 1,837 g, respectively (weight discordance 39%). The APGAR scores were 3/4 and 6/8, respectively. The donor twin died 6 days after delivery due to respiratory failure, and the recipient twin survived. Neonatal echocardiography of the surviving twin showed no tricuspid regurgitation. No long-term follow-up was performed.

Clinical discussion

The traditional diagnostic criteria for TTTS stage 3 were not met and overlapped with the diagnostic criteria for sIUGR type 2. This is the first procedure reported in Indonesia for atypical TTTS with the outcome, one twin survived.

Conclusion

Some TTTS cases do not meet traditional diagnostic criteria and overlap with other monochorionic twin complications.

Doppler Finding, Cardiovascular Function Assessment, and Fetuses' Survival Following the Fetoscopic Laser in Twin-to-Twin Transfusion Syndrome

Introduction: This study aimed to evaluate the effectiveness of selective laser photocoagulation of communicating vessels (SLPCV) on cardiac function in twins with twin-to-twin transfusion syndrome (TTTS). Methods: This retrospective cohort study evaluated 178 women with twin pregnancies complicated with TTTS and scheduled for SLPCV between 16 and 26 weeks of gestation. The severity of TTTS was determined by Quintero staging and the severity of cardiovascular disorders by the CHOP (Children's Hospital of Philadelphia) score. Patient survival was evaluated through a one-month-after-birth follow-up of fetuses. Results: The study revealed significant improvements in Doppler indices in both donors and recipients after SLPCV. The CHOP score also significantly decreased after the intervention. One-month-after-birth survival rates were 55.1% in donors and 56.7% in recipients. Some Doppler indexes of fetuses before SLPCV could predict survival until one month after birth. Conclusion: The study suggests that SLPCV can improve cardiac function in fetuses with TTTS and that some Doppler indexes can predict survival outcomes. Additionally, the severity of TTTS can be a powerful indicator of the severity of cardiovascular complications.

Long-Term Postnatal Follow-Up in Monochorionic TTTS Twin Pregnancies Treated with Fetoscopic Laser Surgery and Complicated by Right Ventricular Outflow Tract Anomalies

Right ventricular outflow tract anomalies (RVOTAs), such as pulmonary stenosis (PS), pulmonary atresia (PA), and pulmonary insufficiency (PI), are typical cardiac anomalies in monochorionic twins, and they are complicated by twin-to-twin transfusion syndrome (TTTS). The aim of this study was to conduct a long-term postnatal cardiological evaluation of prenatal RVOTAs in monochorionic diamniotic twin pregnancies complicated by TTTS and treated with fetoscopic laser surgery (FLS) and to analyze possible prenatal predictors of congenital heart disease (CHD). Prenatal RVOTAs were retrospectively retrieved from all TTTS cases treated with FLS in our unit between 2009 and 2019. Twenty-eight prenatal cases of RVOTAs (16 PI, 10 PS, 2 PA) were observed out of 335 cases of TTTS. Four cases did not reach the postnatal period. CHD was present in 17 of the remaining 24 cases (70.8%), with 10 being severe (58.8%; 10/17); nine cases of PS required balloon valvuloplasty, and one case required biventricular non-compaction cardiomyopathy. The risk of major CHD increased with prenatal evidence of PS and decreased with the gestational age at the time of TTTS and with the prenatal normalization of blood flow across the pulmonary valve. Despite treatment with FLS, the majority of monochorionic diamniotic twin pregnancies complicated by TTTS with prenatal RVOTAs had CHD at long-term follow-up.

Prenatal screening and diagnosis of pulmonary artery anomalies

Congenital pulmonary artery anomalies are rare. Their antenatal diagnosis requires good knowledge of fetal cardiac anatomy because their clinical presentation varies depending on the type and severity of the underlying lesion. Screening of these vascular anomalies can be straightforward in some cases because of significant associated consequences that are detected easily on ultrasound, while other anomalies have considerably less obvious features. There may be an associated genetic syndrome. The aim of this review was to define anomalies of the main pulmonary artery and its branches and to propose, through the identification of suspicious findings during routine antenatal heart examination, an optimal screening method for the pulmonary artery pathway. We propose that pulmonary artery anomalies can be classified antenatally into four types of disorder. Herein we describe 14 cases subgrouped accordingly as: anomalies of the pulmonary valvular region, with stenosis or atresia of the valve (n = 4); conotruncal abnormalities (n = 4); anomalies associated with abnormal origin or course of the pulmonary artery (n = 4); and anomalies associated with abnormal growth of the pulmonary artery and its branches (n = 2). We highlight the need to differentiate the three-vessel view from the three-vessel-and-trachea view when assessing a fetus with a congenital pulmonary artery anomaly. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.