Critical Coarctation of the Aorta in Selective Fetal Growth Restriction and the Role of Coronary Stent Implantation.

INTRODUCTION: Monochorionic twins are at increased risk of congenital heart defects (CHDs). Up to 26% have a birth weight <1,500 g, a CHD requiring neonatal surgery, therefore, poses particular challenges. OBJECTIVE: The aim of the study was to describe pregnancy characteristics, perinatal management, and outcome of monochorionic twins diagnosed with critical coarctation of the aorta (CoA). METHODS: We included monochorionic twins diagnosed with critical CoA (2010-2019) at 2 tertiary referral centers, and we systematically reviewed the literature regarding CoA in monochorionic twins. RESULTS: Seven neonates were included. All were the smaller twin of pregnancies complicated by selective fetal growth restriction. The median gestational age at birth was 32 weeks (28-34). Birth weight of affected twins ranged as 670-1,800 g. One neonate underwent coarctectomy at the age of 1 month (2,330 g). Six underwent stent implantation, performed between day 8 and 40, followed by definitive coarctectomy between 4 and 9 months in 4. All 7 developed normally, except for 1 child with neurodevelopmental delay. Three co-twins had pulmonary stenosis, of whom 1 required balloon valvuloplasty. The literature review revealed 10 cases of CoA, all in the smaller twin. Six cases detected in the first weeks after birth were treated with prostaglandins alone, by repeated transcatheter angioplasty or by surgical repair, with good outcome in 2 out of 6. CONCLUSIONS: CoA specifically affects the smaller twin of growth discordant monochorionic twin pairs. Stent implantation is a feasible bridging therapy to surgery in these low birth weight neonates.

Prevalence, risk factors, and outcome of postprocedural amniotic band disruption sequence after fetoscopic laser surgery in twin-twin transfusion syndrome: a large single-center case series.

BACKGROUND: Postprocedural amniotic band disruption sequence is a condition that is associated with intrauterine interventions, and it is characterized by a constriction of the limbs or umbilical cord by fibrous strands, leading to edema, amputation, and/or fetal demise. OBJECTIVE: To evaluate the prevalence of, risk factors for, and the outcome of postprocedural amniotic band disruption sequence after fetoscopic laser surgery in twin-twin transfusion syndrome cases. STUDY DESIGN: All consecutive cases of twin-twin transfusion syndrome treated with fetoscopic laser coagulation of the vascular anastomoses at our center between January 2002 and March 2019 were included in the study. The occurrence of postprocedural amniotic band disruption sequence in these cases was recorded, and the potential risk factors were analyzed. RESULTS: Postprocedural amniotic band disruption sequence was detected, at birth, in 2.2% (15/672) of twin-twin transfusion syndrome cases treated with fetoscopic laser surgery, in both the recipients (10/15, 67%) and the donors (5/15, 33%). Postprocedural amniotic band disruption sequence primarily affected the lower extremities (11/15, 73%) and, less frequently, the upper extremities (2/15, 13%), both the upper and lower extremities (1/15, 7%), or the umbilical cord (1/15, 7%). Postprocedural amniotic band disruption sequence led to the amputation of toes in 5 of 15 cases (33%) and resulted in fetal demise because of constriction of the umbilical cord in 1 case (7%). The independent risk factors identified for postprocedural amniotic band disruption sequence were lower gestational age at laser surgery (odds ratio per week, 1.43; 95% confidence interval, 1.12-1.79; P=.003) and the presence of postprocedural chorioamniotic membrane separation on antenatal ultrasound examination (odds ratio, 41.66; 95% confidence interval, 5.44-319.25; P<.001). CONCLUSION: The prevalence of postprocedural amniotic band disruption sequence is low, but, when present, it may lead to severe consequences, with amputation of extremities or fetal demise occurring in more than one-third of the cases. Lower gestational age at the time of laser therapy and chorioamniotic membrane separation are independent risk factors for the postprocedural amniotic band disruption sequence.

Perioperative fetal hemodynamic changes in twin-twin transfusion syndrome and neurodevelopmental outcome at two years of age.

OBJECTIVE: To investigate whether perioperative fetal hemodynamic changes in twin-to-twin transfusion syndrome (TTTS) are associated with neurodevelopmental impairment (NDI) at two years. METHODS: Doppler parameters of three sonograms (day before, first day after and 1 week after laser surgery for TTTS) were assessed for correlation with neurodevelopmental outcome at two years (2008-2016). NDI was defined as: cerebral palsy, deafness, blindness, and/or a Bayley-III cognitive/motor developmental test-score > 2SD below the mean. RESULTS: Long-term outcome was assessed in 492 TTTS survivors. NDI was present in 5% (24/492). After adjustment for severe cerebral injury (present in 4%), associated with NDI were: middle cerebral artery peak systolic velocity (MCA-PSV) >1.5 multiples of the median (MoM) 1 day after surgery (odds ratio [OR] 4.96; 95% confidence interval [CI]: 1.17-21.05, P = .03), a change from normal umbilical artery pulsatility index (UA-PI) presurgery to UA-PI >p95 postsurgery (OR 4.19; 95% CI: 1.04-16.87, P = .04), a change from normal to MCA-PSV >1.5MoM (OR 4.75; 95% CI: 1.43-15.77, P = .01). CONCLUSION: Perioperative fetal hemodynamic changes in TTTS pregnancies treated with laser are associated with poor neurodevelopmental outcome. Prospective research on the cerebrovascular response to altered hemodynamic conditions is necessary to further understand the cerebral autoregulatory capacity of the fetus in relation to neurodevelopmental outcome.

Early postnatal cardiac follow-up of survivors of twin-twin transfusion syndrome treated with fetoscopic laser coagulation.

OBJECTIVE: To assess the cardiac function and prevalence of congenital heart defects (CHD) in twin-twin transfusion syndrome (TTTS) survivors. STUDY DESIGN: Prospective follow-up of TTTS pregnancies treated with laser surgery (2015-2018). Echocardiography was performed 1 day and 1 month after birth (corrected for prematurity). Results were compared with a control group of age-matched uncomplicated monochorionic twin-pairs at 1 month. RESULT: Eighty-nine TTTS (168 neonates) and nine control pregnancies (18 neonates) were enrolled. CHD birth prevalence was 9.2% (8/87) in recipients and 13.6% (11/81) in donors (p = 0.37). Four of 19 (21%) were detected prenatally, all pulmonary stenosis. Donors had lower aortic peak velocities compared with recipients at day 1 (0.66 ± 0.15 m/s vs 0.71 ± 0.19 m/s, p = 0.04) and 1 month (1.04 ± 0.21 m/s vs 1.11 ± 0.18 m/s, p = 0.02), but not compared with controls. CONCLUSION: CHD prevalence in TTTS survivors is high, with a low prenatal detection of minor abnormalities. Follow-up fetal echocardiograms and a postnatal echocardiogram should be offered.

The value of echocardiography and Doppler in the prediction of fetal demise after laser coagulation for TTTS: A systematic review and meta-analysis.

This study aimed to investigate the value of echocardiography and Doppler before fetoscopic laser coagulation for twin-twin transfusion syndrome (TTTS) in the prediction of intrauterine fetal demise (IUFD). We performed a systematic review and meta-analysis to compare preoperative parameters between fetuses with and without demise after laser surgery. Eighteen studies were included. Recipient twins have an increased risk of demise in case of preoperative absent/reversed flow (A/REDF) in the umbilical artery (odds ratio [OR] 2.76, 95% confidence interval [CI], 1.78-4.28), absent or reversed a-wave in the ductus venosus (OR 2.32, 95% CI, 1.70-3.16), or a middle cerebral artery peak systolic velocity > 1.5 multiples of the median (MoM) (OR 7.59, 95% CI, 2.56-22.46). In donors, only A/REDF in the umbilical artery (OR 3.40, 95% CI, 2.68-4.32) and absent or reversed a-wave in the ductus venosus (OR 1.66, 95% CI, 1.12-2.47) were associated with IUFD. No association was found between donor-IUFD and preoperative myocardial performance index (MPI). Two studies found an association between abnormal MPI and recipient demise. With this study, we have identified a set of preoperative Doppler parameters predictive of fetal demise after laser surgery. More research is needed to assess the utility of preoperative echocardiographic parameters such as the MPI in predicting IUFD.

Persistent Pulmonary Hypertension of the Newborn in Twin-Twin Transfusion Syndrome: A Case-Control Study.

BACKGROUND: Persistent pulmonary hypertension of the newborn (PPHN) is associated with severe morbidity and mortality. Twin-twin transfusion syndrome (TTTS) is suggested to increase the risk of PPHN. OBJECTIVES: To describe the incidence of PPHN in TTTS twins and to identify risk factors in TTTS twins for the development of severe PPHN. METHODS: Cases with severe PPHN were extracted from our monochorionic twin database (2002-2016). Severe PPHN was defined as severe hypoxaemia requiring mechanical ventilation and inhaled nitric oxide (iNO) treatment, confirmed by strict echocardiographic criteria. A case-control comparison within TTTS survivors was conducted to identify risk factors for PPHN. RESULTS: The incidence of PPHN in TTTS twins was 4% (24/598, 95% confidence interval [CI] 2.7-5.9%) and 0.4% (2/493, 95% CI 0.1-1.5%) in uncomplicated monochorionic twins (odds ratio [OR] 10.3, 95% CI 2.4-43.9; p = 0.002). Two risk factors were independently associated with PPHN: severe prematurity (OR 3.3, 95% CI 1.0-11.4) and recipient status (OR 3.9, 95% CI 1.4-11.0). In TTTS recipients, another risk factor for PPHN is anaemia at birth (OR 7.2, 95% CI 1.8-29.6). CONCLUSION: Clinicians caring for neonates with TTTS should be aware of the 10-fold increased risk of PPHN compared to uncomplicated monochorionic twins. PPHN occurs more often in case of premature delivery and in recipient twins, particularly in the presence of anaemia at birth. As the development of severe PPHN is difficult to predict, we advise that all TTTS twins should be delivered in a tertiary care centre with iNO treatment options.