Changes in Patent Ductus Arteriosus Treatment Strategy and Respiratory Outcomes in Premature Infants

Procedural closure of the patent ductus arteriosus in preterm infants: a clinical practice guideline

IMPORTANCE

Transcatheter closure of the patent ductus arteriosus (PDA) is being increasingly adopted as an alternative to surgical PDA closure in preterm infants.

OBJECTIVE

To develop rigorous clinical practice guideline recommendations on procedural PDA closure in preterm infants.

METHODS

The principles of the GRADE (Grading of Recommendations Assessment, Development and Evaluation) Evidence-to-Decision (EtD) framework were used to develop the guideline recommendations. An e-Delphi survey of 45 experts was conducted and recommendations that reached ≥75% agreement were accepted as consensus.

MAIN RECOMMENDATIONS

Procedural PDA closure may be considered in extremely preterm infants (<28 weeks gestational age) requiring invasive mechanical ventilation >10 postnatal days and confirmed to have a large hemodynamically significant PDA, at centers with high local rates of death and/or bronchopulmonary dysplasia (conditional recommendation). If sufficient institutional expertise is available and patient characteristics are suitable, transcatheter PDA closure may be considered as the preferred approach over PDA ligation (conditional recommendation).

Cardiorespiratory interactions during the transitional period in extremely preterm infants: a narrative review

We aimed to review the physiology and evidence behind cardiorespiratory interactions during the transitional circulation of extremely preterm infants with fragile physiology and to propose a framework for future research. Cord clamping strategies have a great impact on initial haemodynamic changes, and appropriate transition can be facilitated by establishing spontaneous ventilation before cord clamping. Mechanical ventilation modifies preterm transitional haemodynamics, with positive pressure ventilation affecting the right and left heart loading conditions. Pulmonary vascular resistances can be minimized by ventilating with optimal lung volumes at functional residual capacity, and other pulmonary vasodilator treatments such as inhaled nitric oxide can be used to improve ventilation/perfusion mismatch. Different cardiovascular drugs can be used to provide support during transition in this population, and it is important to understand both their cardiovascular and respiratory effects, in order to provide adequate support to vulnerable preterm infants and improve outcomes. Current available non-invasive bedside tools, such as near-infrared spectroscopy, targeted neonatal echocardiography, or lung ultrasound offer the opportunity to precisely monitor cardiorespiratory interactions in preterm infants. More research is needed in this field using precision medicine to strengthen the benefits and avoid the harms associated to early neonatal interventions. IMPACT: In extremely preterm infants, haemodynamic and respiratory transitions are deeply interconnected, and their changes have a key impact in the establishment of lung aireation and postnatal circulation. We describe how mechanical ventilation modifies heart loading conditions and pulmonary vascular resistances in preterm patients, and how hemodynamic interventions such as cord clamping strategies or cardiovascular drugs affect the infant respiratory status. Current available non-invasive bedside tools can help monitor cardiorespiratory interactions in preterm infants. We highlight the areas of research in which precision medicine can help strengthen the benefits and avoid the harms associated to early neonatal interventions.

Secular Trends in Patent Ductus Arteriosus Management in Infants Born Preterm in the National Institute of Child Health and Human Development Neonatal Research Network

We evaluated changes in patent ductus arteriosus (PDA) diagnosis and treatment from 2012 through 2021 in a network of US academic hospitals. PDA treatment decreased among infants born at 26-28 weeks but not among infants born at 22-25 weeks. Rates of indomethacin use and PDA ligation decreased while acetaminophen use and transcatheter PDA closure increased.

Percutaneous Closure of the Patent Ductus Arteriosus in Infants ≤2 kg: IMPACT Registry Insights

OBJECTIVES

Percutaneous patent ductus arteriosus (PDA) closure is becoming the standard of care for definitive closure in progressively smaller and younger neonates. The objective of this study was to assess safety and feasibility of percutaneous PDA closure in patients ≤2 kg.

METHODS

This was a cohort study using the IMPACT Registry (Improving Pediatric and Adult Congenital Treatments) from the American College of Cardiology Foundation's National Cardiovascular Data Registry. Patients who were ≤2 kg at the time of percutaneous PDA closure were included. The primary outcome was the composite of technical failure and/or major adverse event.

RESULTS

A total of 1587 attempted PDA closures were included, with a 3% incidence of technical failure and 5.5% incidence of the composite outcome. Major adverse events were observed in 3.8% of the patients; the most common events were device embolization requiring retrieval and unplanned cardiac or vascular surgery in 1.3% and 1.3% of cases, respectively. The incidence of the composite outcome was associated with the need for arterial access (P < .001) as well as annual hospital volume of percutaneous PDA closures in infants ≤2 kg (P = .001). The incidence of the composite outcome has decreased overtime, whereas median weight at the time of procedure has also diminished.

CONCLUSIONS

Percutaneous PDA closure appears to be safe and feasible procedures in infants ≤2 kg. The incidence of major adverse events has continued to decline over the years and seems to have a strong correlation with individual center case volumes and expertise.

A Global Perspective on PDA Management in the Extremely Premature: Shifting Trend Toward Transcatheter Closure

Patent ductus arteriosus (PDA) is a frequently encountered defect in infants born extremely premature (≤26 weeks' gestation). Historically, closure of the PDA was performed using cyclooxygenase inhibitor medications or by surgical ligations. However, the benefits of PDA closure using these therapies have never been demonstrated, albeit studies have previously not focused on the extremely premature infants. Therefore, there was a worldwide trend toward conservative management of the PDA. With improved survival of extremely premature infants, comorbidities associated with the PDA has increased, resulting in finding alternate treatments such as transcatheter patent ductus arteriosus closure (TCPC) for this population. Currently, there is a renewed interest toward selective treatment of the PDA in this high-risk cohort of small infants. This Comprehensive Review article inspects the globally changing trends in the management of the PDA in premature infants, with a special focus on the rising adoption of TCPC. Moreover, this article compiles data from several neonatal networks worldwide to help understand the problem at hand. Understanding the current management of premature infants and their outcomes is fundamentally essential if pediatric cardiologists are to offer TCPC as a viable therapeutic option for this population. This article aims to serve as a guide for pediatric cardiologists on this topic by compiling the results on landmark clinical trials on PDA management and the controversies that arise from these trials. Comparative outcomes from several countries are presented, including interpretations and opinions of the data from experts globally. This is a step toward coming to a global consensus in PDA management in premature infants.

Combination pharmacotherapy for patent ductus arteriosus: Rationale and evidence

While cyclooxygenase inhibitors have been the most common medications used to facilitate earlier closure of patent ductus arteriosus in preterm infants, adverse effects and low efficacy in extremely low gestational age neonates (ELGANs) have highlighted a need for alternative options. Combination therapy with acetaminophen and ibuprofen is a novel strategy for PDA treatment in ELGANs, as it may facilitate higher ductal closure rates via additive action on two separate pathways inhibiting prostaglandin production. Initial small observational studies and pilot randomized clinical trials indicate potentially higher efficacy of the combination regime to induce ductal closure in comparison to treatment with ibuprofen alone. In this review, we examine the potential clinical impact of treatment failure in ELGANs with significant PDA, highlight the biological rationale in support of studying combination therapy, and review the randomized and non-randomized studies to date. With the rising number of ELGANs receiving neonatal intensive care, who are vulnerable to PDA-related morbidities, there is an urgent need for adequately powered clinical trials to systematically investigate the efficacy and safety of combination therapy for PDA treatment.

Low dose paracetamol for management of patent ductus arteriosus in very preterm infants: a randomised non-inferiority trial

OBJECTIVE

To compare the efficacy of low dose-short course intravenous paracetamol with a conventional dose regimen for early targeted closure of patent ductus arteriosus (PDA).

DESIGN

Single-centre, double-blinded, active controlled, randomised non-inferiority trial.

SETTING

Level III neonatal intensive care unit in Western India.

PATIENTS

Preterm infants <30 weeks of gestation requiring mechanical ventilation, or continuous positive airway pressure with FiO₂ ≥0.35 and diagnosed with a haemodynamically significant PDA (hsPDA) at 18-24 hours of postnatal age.

INTERVENTIONS

Low dose (10 mg/kg/dose 6 hourly for 72 hours) versus conventional dose (15 mg/kg/dose 6 hourly for 120 hours) intravenous paracetamol treatment.

MAIN OUTCOME MEASURES

Comparison of the rates of ductal closure at completion of sixth postnatal day, using a prespecified non-inferiority margin of 20%.

RESULTS

A total of 102 infants were enrolled. The median gestational age and birth weight of the included infants were 26.4 weeks and 830 g. At completion of the sixth postnatal day, closure of PDA was achieved in 92% of infants in the low dose group as compared with 94% of those in the standard dose group (risk difference: -1.6%, 95% CI: -11.6% to 8.5%, p=0.38). The rates of rescue therapies, adverse effects and other neonatal morbidities were comparable in both groups.

CONCLUSION

In very preterm infants on significant respiratory support, low dose-short course intravenous paracetamol treatment was non-inferior to a conventional dosing regime of paracetamol for closure of hsPDA in the first week of postnatal age. Larger studies with narrow margins of non-inferiority are required to confirm our findings.

TRIAL REGISTRATION NUMBER

CTRI/2017/10/010012.

Patent Ductus Arteriosus: A Contemporary Perspective for the Pediatric and Adult Cardiac Care Provider

The burden of patent ductus arteriosus (PDA) continues to be significant. In view of marked differences in preterm infants versus more mature, term counterparts (viewed on a continuum with adolescent and adult patients), mechanisms regulating ductal patency, genetic contributions, clinical consequences, and diagnostic and treatment thresholds are discussed separately, when appropriate. Among both preterm infants and older children and adults, a range of hemodynamic profiles highlighting the markedly variable consequences of the PDA are provided. In most contemporary settings, transcatheter closure is preferable over surgical ligation, but data on longer-term outcomes, particularly among preterm infants, are lacking. The present review provides recommendations to identify gaps in PDA diagnosis, management, and treatment on which subsequent research can be developed. Ultimately, the combination of refined diagnostic thresholds and expanded treatment options provides the best opportunities to address the burden of PDA. Although fundamental gaps remain unanswered, the present review provides pediatric and adult cardiac care providers with a contemporary framework in PDA care to support the practice of evidence-based medicine.

Fechamento Percutâneo do Canal Arterial em Pacientes Prematuros Abaixo de 2 Kg: Experiência Inicial Brasileira

Fundamento

A incidência de ductus arteriosus patente (PCA) pode chegar a 50% em pacientes prematuros. Quando hemodinamicamente significativo, pode ser responsável por tempo de ventilação mecânica prolongado, além de importante fator de risco para o aparecimento de enterocolite necrotizante, hemorragia intraventricular e displasia broncopulmonar nessa população.

Objetivo

O objetivo deste estudo é descrever a experiência inicial do fechamento percutâneo de canal arterial em prematuros pesando menos de 2 kg.

Métodos

Trata-se de estudo prospectivo que compreendeu 14 pacientes consecutivos submetidos a fechamento percutâneo de canal arterial de março de 2020 a fevereiro de 2021 em 6 instituições no Brasil.

Resultados

A idade gestacional média ao nascimento foi de 28,45 ±3,14 semanas, a idade média no momento do procedimento foi de 38,85 ±17,35 dias e o peso médio de 1,41±0,41 kg. Dentre os prematuros, 79% necessitavam de ventilação mecânica e 79% tinham feito uso de, em média, 1,5 ciclos de anti-inflamatórios não esteroides. A maioria dos pacientes teve melhora dos parâmetros ventilatórios e o tempo médio de extubação foi de 12,6 ±7,24 dias. A taxa de sucesso foi de 100%. Não houve mortalidade relacionada ao procedimento.

Conclusão

Este estudo concluiu que o fechamento percutâneo do canal arterial em prematuros é uma realidade no Brasil, com resultados satisfatórios e baixa taxa de complicações.

The Effect of Ibuprofen Exposure and Patient Characteristics on the Closure of the Patent Ductus Arteriosus in Preterm Infants

Spontaneous closure of the ductus arteriosus depends on gestational age (GA) and might be delayed in preterm infants, resulting in patent ductus arteriosus (PDA). Ibuprofen can be administered to enhance closure, but the exposure‐response relationship between ibuprofen and the closure of PDA remains uncertain. We investigated the influence of patient characteristics and ibuprofen exposure on ductus closure. A cohort of preterm infants with PDA and treated with ibuprofen was analyzed. Ibuprofen exposure was based on a previously developed population pharmacokinetic study that was in part based on the same study population. Logistic regression analyses were performed with ductus closure (yes/no) as outcome, to analyze the contribution of ibuprofen exposure and patient characteristics. In our cohort of 263 preterm infants (median GA 26.1 (range: 23.7–30.0) weeks, birthweight 840 (365–1,470) g) receiving ibuprofen treatment consisting of 3 doses that was initiated at a median postnatal age (PNA_start) of 5 (1–32) days, PDA was closed in 55 (21%) patients. Exposure to ibuprofen strongly decreased with PNA_start. Overall, the probability of ductus closure decreased with PNA_start (odds ratio (OR): 0.7, 95% CI: 0.6–0.8) and Z‐score for birthweight (Z_{Birthweight‐for‐GA}; OR: 0.8, 95% CI: 0.6‐1.0), and increased with GA (OR: 1.5, 95% CI: 1.1–1.9). For patients with PNA_start < 1 week, concentrations of ibuprofen, GA, and Z_{Birthweight‐for‐GA} predicted probability of ductus closure. During a window of opportunity for ductus closure within the first days of life, probability of closure depends on GA, Z_{Birthweight‐for‐GA}, and ibuprofen exposure. Increased, yet unstudied dosages might increase the effectivity of ibuprofen beyond the first week of life.

Impact of patent ductus arteriosus shunt size and duration on risk of death or severe respiratory morbidity in preterm infants born in China

The purpose of this study is to assess whether duration and size of the arterial duct were associated with severe respiratory morbidity and mortality in preterm infants. All echocardiography evaluations for patent ductus arteriosus (PDA) in a cohort of preterm infants, born at a gestational age less than 28 weeks, from birth up to 36 weeks of postconceptional age or final ductal closure were reviewed. Ductal size was measured at the pulmonary end. PDA was classified as small (E1: ductal diameter (DD) ≤ 1.5 mm), moderate (E2: 1.5 mm < DD ≤ 2.5 mm), or large (E3) (DD > 2.5 mm). The primary outcome was adverse outcome defined by the composite outcome of bronchopulmonary dysplasia (BPD) or death. Infants in whom the primary outcome occurred were classified as "high-risk" whereas patients who did not satisfy this outcome were classified as "low-risk". Intergroup comparison (high vs. low risk) was performed using univariate and multivariate analyses. A total of 135 infants, born between 2010 and 2020, were evaluated. The primary outcome was satisfied in 46 (34.1%) patients. The high-risk group was characterized by increased duration of exposure to PDA of any (E1/E2/E3) grade (44 vs. 25.5 days, p = .0004), moderate or large (E2/E3) PDA (30.5 vs. 11.5 days, p < .0001), moderate (E2) PDA (10.8 vs.6 days, p = 0.05), and large (E3) PDA (11.5 vs.0 days, p < .0001) compared with low-risk group. Lower gestational age, prolonged duration of mechanical ventilation, higher rate of inotrope use, pharmacological therapy, and PDA ligation were also associated with development of BPD or death (high-risk group). After adjusting for confounders, the rate of inotrope use [OR 2.688, 95% CI (1.011-7.142), p = 0.047], duration of large (E3) PDA [OR 1.060, 95% CI (1.005-1.118), p = 0.03], and mechanical ventilation [OR 1.130, 95% CI (1.064-1.200), p = 0.0001] were independently associated with the composite of BPD or death. Among infants who developed BPD, 27 were classified as grade I and 18 as grade II BPD, respectively. Infants with grade II BPD had prolonged MV (20.0 vs. 9.0 days, p = 0.024), prolonged exposure to PDA of any grade (55.8 vs. 36.0 days, p = 0.03), and prolonged exposure to large (E3) PDA compared with infants with grade I BPD.   Conclusion: Prolonged exposure to a large PDA was associated with severe respiratory morbidity and mortality in preterm infants. The modulator role of early intervention, in the most pathologic shunts, on severe respiratory morbidity in preterm infants should be tested in well-designed clinical trials. What is Known: • Current guidelines recommended against accelerating PDA closure of preterm infants within 2 weeks of life, with low certainty evidence indicating improved long-term outcomes. • Recent studies suggest that conservative approach regarding PDA management has detrimental effects on the respiratory outcomes in a subgroup population. What is New: • Persistent patency of significant PDA is associated with increased risk of BPD/death in extremely preterm infants. • Targeted intervention of PDA is beneficial for the at-risk preterm infants with increased PDA hemodynamic significance.