Inadvertent irreversible closure of arterial duct following therapeutic use of transplacental indomethacin in a fetus with severe Ebstein's anomaly and circular shunt.

We report on a fetal case of Ebstein's anomaly with severe tricuspid regurgitation, functional pulmonary atresia and progressive circular shunting (CS) across a widely patent ductus arteriosus (DA) and regurgitant pulmonary valve, contributing to significant systemic hypoperfusion. To mitigate the extent of CS and allow the pregnancy to continue, maternal non-steroidal anti-inflammatory drug (NSAID) therapy with indomethacin was started at 33 + 5 weeks to induce DA constriction. Rather than achieving the desired narrowing of the DA, the treatment led to its complete closure and only minimal antegrade flow across the pulmonary valve. While closure of the DA resulted in the anticipated improvement in fetal hemodynamics, at birth, the child was at risk of severe hypoxemia and its consequences due to the lack of adequate pulmonary perfusion. Reduction and eventual discontinuation of the NSAID treatment did not result in DA reopening. Our experience illustrates the risk of unintended irreversible DA closure when NSAIDs are used to treat CS. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Tetralogy of Fallot With Absent Pulmonary Valve and Nonconfluent Pulmonary Arteries: A Management Conundrum.

Tetralogy of Fallot with absent pulmonary valve syndrome is a rare form of congenital heart disease. Among the different variations with this rare anomaly is nonconfluent pulmonary artery branches with anomalous origin of the left pulmonary artery from the ductus arteriosus. The authors present one such case which was diagnosed prenatally to have tetralogy of Fallot with absent pulmonary valve and identified postnatally to have nonconfluent pulmonary artery branches in addition. We discuss the conundrum of respiratory management in this patient pre- and postoperatively due to a unique ventilation perfusion mismatch problem, which varies between the two lungs.

Diagnosis of major heart defects by routine first-trimester ultrasound examination: association with increased nuchal translucency, tricuspid regurgitation and abnormal flow in ductus venosus.

OBJECTIVE: To examine the association between fetal major heart defects and increased nuchal translucency thickness (NT), tricuspid regurgitation and abnormal flow in the ductus venosus in a large population of singleton pregnancies undergoing routine ultrasound examination at 11-13 weeks' gestation. METHODS: This was a retrospective study of prospectively collected data from singleton pregnancies attending for a routine ultrasound scan at 11-13 weeks' gestation, which included examination of fetal anatomy, measurement of NT and assessment of blood flow across the tricuspid valve and in the ductus venosus, according to a standardized protocol. The incidence of fetal NT ≥ 95th and ≥ 99th percentiles, tricuspid regurgitation and reversed a-wave in the ductus venosus in fetuses with and those without a major heart defect was determined and the performance of each marker and their combination in the detection of major heart defects was calculated. RESULTS: The study population of 93 209 pregnancies with no apparent chromosomal abnormality included 211 (0.23%) with a fetal major heart defect and 92 998 morphologically normal neonates. In 113 (53.6%) cases with a major heart defect, the diagnosis was made at the 11-13-week scan, in 82 (38.9%) at the 18-24-week scan, in 10 (4.7%) at the third-trimester scan and in six (2.8%) postnatally. At the 11-13-week scan, we diagnosed all cases of tricuspid or pulmonary atresia and polyvalvular dysplasia, > 90% of cases of hypoplastic left heart syndrome or atrioventricular septal defect, about 60% of complex heart defects and cases of left atrial isomerism (interrupted inferior vena cava with normal intracardiac anatomy), 30-40% of cases of tetralogy of Fallot and arch abnormalities, 25% of tricuspid valve abnormalities and about 15% of cases of transposition of the great arteries, but none of aortic or pulmonary stenosis or common arterial trunk. Fetal NT ≥ 95th or ≥ 99th percentile, tricuspid regurgitation or abnormal ductus venosus flow was observed in 77 (36.5%), 45 (21.3%), 61 (28.9%) and 58 (27.5%) fetuses with a major heart defect, respectively, and in 5678 (6.1%), 857 (0.9%), 1136 (1.2%) and 1644 (1.8%) of those without a heart defect. Any one of NT ≥ 95th percentile, tricuspid regurgitation or abnormal flow in the ductus venosus was found in 117 (55.5%; 95% CI, 48.5-62.3%) fetuses with a heart defect and in 8166 (8.8%; 95% CI, 8.6-9.0%) of those without a heart defect. Any one of NT ≥ 99th percentile or the other two markers was found in 99 (46.9%; 95% CI, 40.0-53.9%) fetuses with a heart defect and in 3517 (3.8%; 95% CI, 3.7-3.9%) of those without a heart defect. CONCLUSION: At 11-13 weeks' gestation, measurement of fetal NT and assessment of flow across the tricuspid valve and in the ductus venosus can lead to early diagnosis of major heart defect. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Negligible risk of prenatal ductus arteriosus closure or fetal renal impairment after third-trimester paracetamol use: evaluation of the German Embryotox cohort.

OBJECTIVE: Risk of fetotoxicity after paracetamol exposure in the third trimester. DESIGN: Observational cohort study and retrospective case assessment. SETTING: Germany, 2008-2017. POPULATION: Pregnant women exposed to paracetamol. METHODS: Prospectively enrolled third-trimester pregnancies that had been exposed to paracetamol (604) were compared with pregnancies exposed to paracetamol in the first and/or second trimester only (1192). Exclusion criteria were exposure to nonsteroidal anti-inflammatory drugs (NSAIDs) in the second or third trimester. Additionally, the Embryotox 'adverse drug reaction in pregnancy' database was screened for cases of fetotoxicity. MAIN OUTCOME MEASURES: The prenatal study end points focused on narrowing or closure of ductus arteriosus Botalli, late fetal death, and oligohydramnios. The postnatal end points included patent ductus arteriosus (PDA), primary pulmonary hypertension (PPHT), and impaired renal function. RESULTS: In both cohorts, no fetus with intrauterine narrowing or closure of the ductus arteriosus Botalli was reported (0/604 versus 0/1192). Oligohydramnios was diagnosed at a similar frequency in both cohorts: 1.3% (8/604) versus 1.6% (19/1192). There was one stillbirth in the study cohort (1/604, 0.2%) and four stillbirths in the comparison cohort (4/1192, 0.3%). The rates of PDA in neonates were similar: 0.7% (4/615) versus 0.7% (9/1212). PPHT as well as serious postnatal renal disorders were reported once in each cohort. In 12 out of 96 retrospective cases, there were indicators for study end points; however, co-exposure to NSAIDs or complex situations weaken the assumption of paracetamol toxicity. CONCLUSIONS: Fetal cardiovascular or renal toxicity of maternal third-trimester paracetamol use appears to be negligible. TWEETABLE ABSTRACT: Paracetamol use in the third trimester does not seem to be associated with a relevant risk of fetotoxicity.

Tetralogy of Fallot with absent pulmonary valve-When the ductus is present: A case of isolated branch pulmonary artery and review of literature.

Tetralogy of Fallot/Absent Pulmonary Valve (TOF/APV) has been classically associated with the absence of a patent ductus arteriosus (PDA). We present a rare case of APV in TOF with a discontinuous left pulmonary artery (LPA) that was suspected during fetal echocardiogram. Postnatal echocardiogram confirmed the origin of a hypoplastic LPA from the PDA. Despite an aneurysmal (right pulmonary artery) (RPA), axial imaging demonstrated widely patent tracheobronchial system with no evidence of bronchial compression. Clinically, the child required only minimal respiratory support. Genetic testing was positive for 22 q11deletion, commonly associated with this lesion. Surgery consisted of unifocalization of the discontinuous LPA with placement of a valved pulmonary homograft during complete repair of this lesion. Our case highlights the importance of prenatal detection, to aid in the prompt initiation of prostaglandins so as to ensure early rehabilitation of the left lung. Inability to visualize one of the branch pulmonary arteries (PA's) and a PDA on fetal echocardiogram in TOF/APV must raise suspicion for an eccentric branch PA with ductal origin.

Fetal hemodymanic effects on ductus arteriosus development and influences on postnatal management in infants with ductal-dependent pulmonary blood flow.

The ductus arteriosus (DA) has been studied since Galen. Initially after birth in neonates with obstruction to pulmonary blood flow, DA patency is integral to ensure output and oxygenation. While DA stenting dates back 25 years, there is emerging interest in better understanding how and when to utilize this strategy as an alternative to surgical shunt placement or ongoing prostaglandin administration. Understanding the normal fetal circulation and the perturbations that affect flow and oxygenation is integral to comprehending how normal DA anatomy and morphology may change and how this may influence technical and clinical considerations. In the normal human fetus the great majority of descending aorta circulation comes from the DA, whereas this is a small minority in pulmonary outflow lesions, resulting in size and angle abnormalities. Study of the DA morphology has previously sought to identify patients requiring early intervention and more novel classifications are contributing to knowledge of complications and increasing the likelihood of success. As well, optimal patient selection for aorto-pulmonary shunt vs DA stent remains unclear. This review seeks to convey how fetal circulation can affect the DA, how other clinical considerations such as neurocognitive development support these finding and influence management, and emphasize that the variability in the DA will affect suitability for stenting, which requires further study as guidelines and standards are developed.

Prostaglandin E2 Receptor EP4 Inhibition Contracts Rat Ductus Arteriosus.

BACKGROUND: Patent ductus arteriosus (PDA) is common in premature infants. Cyclooxygenase inhibitors such as indomethacin, which inhibit prostaglandin E2(PGE2) synthesis, are currently the sole treatments for patients with PDA. Their efficacy are, however, frequently limited, and adverse effects are problematic. Because the PGE2-specific receptor EP4 selectively expresses in rat ductus arteriosus (DA), it is hypothesized that EP4 inhibition would promote DA closure with fewer side-effects.Methods and Results:A new chemical compound EP4 antagonist, RQ-15986 (renamed from CJ-042794), was used. Whether RQ-15986 selectively contracted the DA was examined by measuring the isometric tension of rat DA ex vivo at embryonic day 19 (e19) and e21. RQ-15986 at a dose of 10-6mol/L increased the isometric tension of the DA up to 44.8±6.2% and 69.1±12.9% to the maximal KCl-induced tension at e19 and e21 respectively. The effect of RQ-15986 on rat DA in vivo was also tested by using a rapid whole-body freezing method. RQ-15986 inhibited PGE1-induced DA dilatation in neonatal rats. Furthermore, RQ-15986 contracted the DA in a dose-dependent manner, and the constriction was greater at e21 than at e19. Moreover, RQ-15986 did not contract the aorta or the marginal artery of the colon. CONCLUSIONS: EP4 inhibition contracts rat DA with fewer side-effects. EP4 inhibition is a promising alternative strategy to treat patients with PDA.

Dysfunction of the foetal arterial duct results in a wide spectrum of cardiovascular pathology.

OBJECTIVE: Foetal ductal problems may have various cardiopulmonary consequences. This study aimed to identify the spectrum of ductus arteriosus (DA) dysfunction (closure, constriction, kinking, aneurysm and thrombosis) and the resultant clinical and echocardiographic presentation in foetuses and neonates. METHODS AND RESULTS: This is a retrospective analysis of serial pre- and post-natal data of 27 cases of foetal ductal dysfunction diagnosed at a median gestational age of 33 weeks (range 20-39). The most common abnormalities observed were premature closure of the DA in 56% (15/27) and constriction in 29% (8/27). Right ventricular hypertrophy was present in 75% (n = 11/15) of foetuses with premature DA closure, while ventricular dilation (4/7, 57%) was a more common feature in foetuses with ductal constriction. After birth, 63% (17/27) of new borns presented with cyanosis and pulmonary hypertension that required active treatment. Three infants died after birth. Abnormalities resolved spontaneously after birth in about 50% of patients. In some children, pulmonary valve stenosis and regurgitation was progressive and required further treatment. CONCLUSIONS: An abnormal right heart on foetal four-chamber ultrasound view should alert the sonographer to the possible presence of foetal ductal dysfunction. Ductal occlusion, transient or fixed constriction, kinking and aneurysm formation are associated with foetal cardiopulmonary sequelae. Symptoms and pathology is probably related to the type, foetal age, rapidity of progression and duration of intrauterine ductal dysfunction. Correspondingly, clinical outcomes vary ranging from little or no symptoms to severe respiratory distress and even foetal or neonatal death.

Pathogenesis of solitary right aortic arch: a mass effect hypothesis based on observations of serial human embryonic sections.

In general, solitary right aortic arch carries the left-sided ductus arteriosus communicating between the left subclavian and pulmonary arteries or the right-sided ductus connecting the descending aorta to the left pulmonary artery. Serial sections of fifteen 5- to 6-week-old embryos and ten 8- to 9-week-old fetuses suggested that the pathogenesis was unrelated to inversion due to dysfunction in gene cascades that control the systemic left/right axis. With inversion, conversely, the ductus or the sixth pharyngeal arch artery should connect to the right pulmonary artery. The disappearance of the right aortic arch started before the caudal migration of the aortic attachment of the ductus. Sympathetic nerve ganglia developed immediately posterior to both aortae, with a single embryonic specimen showing a large ganglion at the midline close to the union of the aortic arches. These ganglia may interfere with blood flow through the distal left arch, resulting in the ductus ending at the descending aorta behind the oesophagus. In another fetus examined, a midline shift of the ductus course resulted in the trachea curving posteriorly. Therefore, solitary right arch is likely to accompany abnormalities of the surrounding structures. The timing and site of the obstruction should be different between types: an almost midline obstruction near the aortic union needed for the development of the left-sided ductus and a distal obstruction near the left subclavian arterial origin needed for the development of the right-sided ductus. A mass effect of the sympathetic ganglia may explain the pathogenesis of any type of anomalous ductus arteriosus shown in previous reports of the solitary right arch.

Patent ductus arteriosus.

Patent ductus arteriosus in adults is usually an isolated lesion with a small to moderate degree of shunt, as a larger shunt becomes symptomatic earlier in childhood. The classic murmur of patent ductus arteriosus may be the first clue to its presence, or it may be detected accidently by transthoracic echocardiography, computed tomography, or magnetic resonance angiography for an unrelated condition. The percutaneous approach is safe and effective in more than 98% of patients. Subacute bacterial endocarditis prophylaxis is not indicated routinely except for 6 months following the closure percutaneously or surgically.

Patent ductus arteriosus in the preterm infant: new insights into pathogenesis and clinical management.

Postnatal closure of the ductus arteriosus is crucial in the circulatory adaptation of the newborn to extrauterine life. In recent years, many studies have been performed to improve our understanding of both the physiology of the ductus arteriosus in the fetus and newborn, and the mechanisms underlying persistent ductal patency in the preterm infant. The pharmacological treatment of patent ductus arteriosus (PDA) remains a controversial issue. This article reviews the recent literature on the pathogenesis and clinical management of PDA in the preterm infant.

Adult presentation of combined unilateral atresia of the right proximal pulmonary artery and left patent ductus arteriosus: case report and embryological considerations.

We report on a rare case of combined unilateral atresia of the proximal right pulmonary artery (PA) and left patent ductus arteriosus (PDA). A 46 year-old female patient with known PDA and associated advanced pulmonary arterial hypertension presented with progressive hemoptysis and increasing exertional dyspnea. Computed tomography of the chest proved the presence of the known PDA but surprisingly failed to demonstrate an extrapulmonary proximal right PA. We show the imaging features and discuss the embryological background of this rare congenital cardiovascular malformation.

Delayed neonatal closure of the ductus arteriosus following early in utero exposure to indomethacin in the rat.

BACKGROUND: Indomethacin is used to close the patent ductus arteriosus in premature infants and for tocolysis of preterm labor. Clinically and experimentally, early in utero exposure to indomethacin induces the paradoxical delay of postnatal closure of the ductus arteriosus. OBJECTIVES: To clarify the pharmacological nature of the delay of closure of the ductus arteriosus in the rat. METHODS: We studied early in utero exposure to indomethacin (dose and timing) in addition to other drugs, inducing a delay in postnatal ductal closure. Pregnant rats at near term were studied by cesarean section on gestational day 21 (D21), incubated in room air at 33 degrees C, followed by rapid whole-body freezing. RESULTS: The delay in closure of the ductus arteriosus was dose dependent. A large dose of indomethacin (10 mg/kg) 1 or 2 days before birth induced a delay of 3-4 times. A timing study revealed maximum delay with administration of indomethacin 2 days before birth and minimum delay with administration 5 days before. Aspirin, ibuprofen, the selective COX1 inhibitor SC 560, the selective COX2 inhibitor rofecoxib and a prostaglandin EP(4) receptor blocker, ONO-208, all delayed neonatal ductal closure following maternal administration on D19 and D20. CONCLUSIONS: The delay by indomethacin was dose dependent. The maximum delay was induced by 2 doses of 10 mg/kg indomethacin on D19 and D20. The delay was induced by a decreased stimulus to the prostaglandin EP(4) receptor system in the last 2 days in utero. The delay was temporary with recovery 3 days or more after exposure.

The effects of caffeine on the preterm sheep ductus arteriosus.

Caffeine and other methyl xanthines are widely used in the neonatal period. A recent, randomized, placebo-controlled, multicenter trial found that infants who were randomly assigned to caffeine treatment had less need for pharmacologic and/or surgical closure of a patent ductus arteriosus (PDA). We hypothesized that the decreased need for pharmacologic and surgical closure of the PDA after caffeine treatment might be due to a direct effect of caffeine on ductus contractility. We examined preterm fetal lamb ductus arteriosus (from 24 fetuses, 105 +/- 4 d of gestation, term = 147 d), in vitro to determine the direct effects of caffeine on the isometric tension of the ductus arteriosus. Caffeine (0.003-0.3 mM) had no direct effect on ductus arteriosus tension, nor did it affect the contractile response of the ductus arteriosus to increasing oxygen concentrations. Caffeine's lack of effect was observed in both the presence and absence of indomethacin and NG-nitro-L-arginine methyl ester (L-NAME) (inhibitors of prostaglandin and nitric oxide production). In conclusion, we found no evidence of a direct effect of therapeutic caffeine concentrations on ductus contractility.

Mechanisms regulating the ductus arteriosus.

A patent ductus arteriosus (PDA) results in increased pulmonary blood flow and redistribution of flow to other organs. Several co-morbidities (i.e., necrotizing enterocolitis, intracranial hemorrhage, pulmonary edema/hemorrhage, bronchopulmonary dysplasia, and retinopathy) are associated with the presence of a PDA, but whether or not a PDA is responsible for their development is still unclear. In this review, comparative physiology between the full term and preterm newborn and the barriers preventing the necessary cascade of events leading to permanent constriction of the PDA are reviewed.