Patent ductus arteriosus (PDA) is a common circulatory condition in preterm infants, particularly those with lower gestational age or birth weight [1]. Delayed postnatal closure of the ductus arteriosus may lead to increased pulmonary blood flow and reduced systemic perfusion due to left-to-right shunting [2,3], and these hemodynamic changes have been associated with major complications in preterm infants [4,5].

However, the clinical significance of PDA and the need for treatment in preterm infants remains unclear. Even with a similar anatomical ductal size, the hemodynamic significance and clinical impact may vary depending on gestational age, postnatal age, respiratory and hemodynamic status, comorbidities, and the direction and volume of shunt flow through the ductus arteriosus [6-8]. In particular, PDA has been considered both a potential direct contributor to adverse clinical outcomes and a biomarker reflecting physiological vulnerability and severity of underlying disease in preterm infants [3,9,10].

This uncertainty in pathophysiological interpretation has led to substantial variation in treatment strategies. In the 1970s, prophylactic and aggressive treatment approaches using pharmacological therapy and early surgical ligation became widespread [11-13]. However, from the 1990s onward, large-scale clinical studies and systematic reviews raised concerns regarding the lack of consistent evidence for improved clinical outcomes, gradually weakening the rationale for routine ductal closure strategies [10,14-16].

Accordingly, recent clinical guidelines emphasize a selective approach that identifies hemodynamically significant PDA based on repeated clinical assessments and echocardiographic evaluation rather than ductal patency alone [17,18]. In parallel with large-scale clinical trials evaluating the efficacy of various pharmacological treatments [16,19,20], conservative management aimed at alleviating left-to-right shunting and heart failure symptoms while allowing spontaneous ductal closure has also become an important treatment strategy [14,21].

This position statement was developed by expert panels from the Korean Society of Neonatology and the Korean Society of Pediatric Cardiology through a comprehensive review of key evidence-based literature, including randomized controlled trials, systematic reviews and meta-analyses, and current international guidelines on the diagnosis and management of PDA in preterm infants. This paper aims to review the clinical evidence for PDA treatment in preterm infants and to propose a decision-making framework that reflects the Korean neonatal care setting.

The ductus arteriosus is a vessel that normally exists during fetal life, connecting the aorta and pulmonary artery. In healthy term infants, the ductus arteriosus undergoes functional closure through smooth muscle contraction within 48 to 72 hours after birth, followed by complete anatomical closure over the ensuing days. In preterm infants; however, ductal closure rates are lower and closure is often delayed due to elevated plasma prostaglandin E2 levels, immature vascular intimal structure, and various hemodynamic factors associated with preterm birth. PDA refers to persistent ductal patency afterbirth, resulting in blood flow shunting of varying direction and magnitude depending on the relative balance between pulmonary and systemic vascular resistance [9,12,22].

The incidence of PDA in preterm infants increases with decreasing gestational age and birth weight, and the timing of spontaneous closure is also delayed in more immature infants [1,9,12]. Ductal patency rate on postnatal day 4 is approximately 10% in preterm infants at 30 to 37 weeks of gestational age, rising to approximately 80% at 25 to 28 weeks and approximately 90% at 24 weeks [23]. The rate of spontaneous closure within the first 7 days of life has been reported as 78%, 77%, and 41% in infants born at <37, <30, and <28 weeks of gestation, respectively [23]. Similar findings were reported in a single-center Korean study, in which the incidence of hemodynamically significant PDA was 21% at 27 to 28 weeks of gestation, approximately 64% at 25 to 26 weeks, and approximately 93% at 23 to 24 weeks, with median time to spontaneous closure of 36, 41, and 53 days of life, respectively [24]. Thus, prematurity itself is the strongest risk factor for PDA. Additional risk factors associated with persistent or symptomatic PDA include lack of antenatal steroid administration, need for mechanical ventilation, respiratory distress syndrome, perinatal asphyxia, hypoxia, excessive fluid intake, and intrauterine growth restriction [1,9,12].

The classical pathophysiological model of PDA describes how left-to-right shunting through the ductus arteriosus may alter the distribution of pulmonary and systemic blood flow. According to this model, increased left-to-right shunting leads to elevated pulmonary blood flow, resulting in pulmonary congestion, pulmonary edema, and worsening respiratory failure, and in severe cases, may precipitate pulmonary hemorrhage or congestive heart failure [2,12]. Regarding systemic blood flow redistribution, fluctuations in ascending aortic blood flow have been associated with cerebral blood flow instability [25,26], whereas reduced aortic perfusion has been hypothesized to contribute to gastrointestinal and renal ischemia, metabolic acidosis, oliguria, renal failure, and necrotizing enterocolitis (NEC) [1,3,12]. However, these mechanisms should be understood as part of a traditional and theoretical framework. Recent large-scale clinical trials have shown that, although pharmacological treatment consistently achieves higher ductal closure rates than conservative management, the incidence of complications such as bronchopulmonary dysplasia (BPD) is not reduced and, in some studies, may even be higher in the treatment group [14-16]. This suggests that the association between PDA and major morbidities, including intraventricular hemorrhage, BPD, and NEC, cannot be explained solely by the hemodynamic consequences of ductal shunting, but instead reflects the complex interplay between prematurity itself, comorbid conditions, and therapeutic interventions [27]. Therefore, PDA should be understood as a continuum ranging from a discrete disease entity to a biomarker of underlying vulnerability, and its clinical significance should be determined individually for each patient [10,17].

The diagnosis of hemodynamically significant PDA requires a comprehensive evaluation of the effects of left-to-right shunting on pulmonary blood flow and systemic perfusion using a multifaceted approach that integrates clinical findings, echocardiographic features, and serum biomarkers. Clinical manifestations are diverse and may include traditional signs such as murmur, hyperdynamic precordium, and bounding pulses; findings suggestive of pulmonary overcirculation, including increased oxygen requirement, respiratory instability, and increased need for mechanical ventilatory support; and findings suggestive of systemic hypoperfusion, including hypotension, decreased urine output, feeding intolerance, and abdominal distension [1,3,9]. However, as these findings are nonspecific and commonly observed in preterm infants, clinical signs alone are insufficient to confirm hemodynamically significant PDA or guide treatment decisions [5,6].

Echocardiography is the key tool for confirming the presence of PDA and assessing its hemodynamic significance. Ductal diameter and shunt size, as well as various hemodynamic parameters, should be considered together. Representative assessment parameters include indices reflecting increased pulmonary blood flow and left ventricular volume overload, such as the left atrial-to-aortic ratio, left ventricular end-diastolic diameter, mitral Doppler early/atrial (E/A) ratio, defined as the ratio of early diastolic filling velocity to late diastolic filling velocity due to atrial contraction, and isovolumetric relaxation time; findings suggestive of systemic hypoperfusion, such as decreased or reversed end-diastolic flow in the descending aorta and superior mesenteric, renal, and cerebral arteries; and indices of cardiac function, including left ventricular volume overload [6,8]. However, echocardiography reflects hemodynamic status at a single point in time and therefore has limitations in fully capturing the dynamic changes in hemodynamic status over time [28,29]. Furthermore, its interpretation may vary according to clinical factors such as gestational age, postnatal age, respiratory distress syndrome, chorioamnionitis, perinatal asphyxia, and antenatal steroid administration [2,3].

Not all preterm infants require echocardiography for PDA evaluation. In clinically stable, relatively lower-risk infants, such as those born at ≥28 to 30 weeks of gestation, the likelihood of spontaneous closure is high, and watchful observation alone may be sufficient. In contrast, early targeted neonatal echocardiography is recommended in infants with PDA-related signs or symptoms and in relatively higher-risk groups, such as those born at <26 to 28 weeks of gestation or those with severe respiratory distress syndrome, even in the absence of specific clinical symptoms [17].

The purpose of early targeted neonatal echocardiography is not only to confirm the presence of PDA but also to identify patients with moderate-to-severe high-flow shunting and hemodynamic imbalance who should be considered for closure treatment. It is also useful for excluding conditions such as pulmonary arterial hypertension, in which ductal closure could be harmful [17,29]. However, echocardiographic parameters alone cannot determine the treatment strategy for PDA. The American Society of Echocardiography also recommends that the diagnosis of hemodynamically significant PDA should integrate gestational age, postnatal age, and clinical evidence suggestive of pulmonary overcirculation and systemic hypoperfusion rather than relying solely on echocardiographic parameters [22].

The biomarkers B-type natriuretic peptide and N-terminal pro-B-type natriuretic peptide can be used as screening tools, as they reflect the hemodynamic burden associated with PDA; however, they are limited by their nonspecificity. Systematic reviews have also shown that these markers do not demonstrate sufficient diagnostic accuracy to replace echocardiography, and their use as supplementary indicators is considered appropriate [17,30].

The traditional first-line treatment for PDA in preterm infants is pharmacological therapy, which induces ductal closure through inhibition of prostaglandin synthesis [1,9,12]. Representative agents include indomethacin, ibuprofen, and paracetamol. Indomethacin, a cyclooxygenase inhibitor, has excellent closure efficacy; however, it carries risks of adverse effects, including reduced renal, cerebral, and mesenteric blood flow and consequent renal dysfunction, intraventricular hemorrhage, and gastrointestinal bleeding [12]. Ibuprofen has demonstrated closure efficacy comparable to that of indomethacin, with relatively fewer adverse effects on organ blood flow, and is therefore preferred, although it carries the potential risk of gastrointestinal disturbances and impaired platelet function. Paracetamol, a peroxidase inhibitor, has increasingly been used as an alternative in recent years. It may be considered when conventional pharmacological agents are difficult to use or when treatment has failed, and has been reported to have comparatively fewer renal and gastrointestinal adverse effects [31]. Drug selection should comprehensively account for blood pressure, oxygen saturation, urine output, cerebral blood flow status, gestational age, and birth weight, and the dosage and route of administration may vary accordingly.

Given the limitations and adverse effects of pharmacological treatment, conservative management has emerged as an important alternative strategy. Conservative management is not merely passive observation, but rather a proactive strategy that actively mitigates pulmonary overcirculation and heart failure symptoms through various interventions to facilitate spontaneous ductal closure [10,18]. Key approaches include fluid restriction, judicious use of diuretics when indicated, and appropriate ventilatory management [12]. Fluid restriction helps reduce circulating blood volume and the pulmonary blood flow burden, whereas diuretics should be used selectively when clinically meaningful fluid accumulation or pulmonary edema is present. Mechanical ventilation is used with the expectation of controlling pulmonary overcirculation through appropriate airway pressure management strategies, including increased positive end-expiratory pressure [3,12]. In infants with mild symptoms or limited hemodynamic significance, serial echocardiographic monitoring with expectant observation is a reasonable option [14,21,32].

Under conservative management, the ductus arteriosus in preterm infants often undergoes spontaneous closure over time even without active intervention, with the likelihood of closure increasing with higher gestational age and birth weight. Spontaneous closure has been reported in approximately 73% of preterm infants born at ≥28 weeks of gestation and, ultimately, in approximately 90% of infants born before 26 weeks of gestation [33]. Even when PDA persists at discharge, subsequent spontaneous closure remains possible, with approximately 50% closing by 9 months and approximately 80% by 2 years of age [33]. A Korean randomized controlled trial also demonstrated that 89% of infants in the conservative management group achieved spontaneous closure by discharge and 94% by 2 years of age [34]. The timing of spontaneous closure varies markedly according to gestational age. In a retrospective study, median times to ductal closure were 6 days at ≥30 weeks, 8 days at 28 to 29 weeks, 13 days at 26 to 27 weeks, and 71 days at <26 weeks, indicating a sharp decline in the rate of spontaneous closure with decreasing gestational age [35]. This trend has also been observed in Korea, with median closure times of 36 days at 27 to 28 weeks, 41 days at 25 to 26 weeks, and 53 days at 23 to 24 weeks of gestation [24]. The relatively high rates of spontaneous closure observed even at younger gestational ages, despite differences in timing, support the role of a selective conservative approach as an important strategy [15,16]. In clinical practice, conservative management has been increasingly adopted. According to data from the National Institute of Child Health and Human Development Neonatal Research Network (NICHD NRN), the rate of active treatment, including pharmacological therapy or surgery, among preterm infants born at 26 to 28 weeks of gestation declined from 21% in 2012 to 16% in 2021 [36]. A similar trend has also been observed in Korea, suggesting a shift toward watchful observation under conservative management in a greater proportion of patients [4].

Surgical ligation is typically performed via a small thoracotomy, with closure of the ductus arteriosus using sutures or clips [13,37]. It is selectively considered when repeated pharmacological treatment has failed or when pharmacological therapy is contraindicated or carries a high risk of adverse effects due to conditions such as renal dysfunction, severe thrombocytopenia, active bleeding, or NEC. It may also be considered in cases of severe heart failure or pulmonary edema refractory to prolonged conservative management, resulting in failure to wean from mechanical ventilation, or in cases of persistent failure to thrive attributable to ongoing shunt flow. It should be noted, however, that despite its reliable closure efficacy, surgical ligation carries risks of various complications, including postoperative cardiopulmonary instability, also known as post-ligation syndrome, recurrent laryngeal nerve palsy, phrenic nerve injury, chylothorax, pneumothorax, hemorrhage, and infection [13,37]. Associations between surgical ligation and increased incidences of BPD, retinopathy of prematurity, and neurodevelopmental impairment have also been reported. However, these findings should be interpreted with caution, as it remains unclear whether they reflect the effects of the surgery itself or the severity of the underlying disease. Therefore, surgical ligation should be reserved for selected patients with clear indications [17,18]. Although rare, recanalization at the ligation site may occur, and regular echocardiographic follow-up after the procedure is recommended.

Transcatheter ductal closure is a minimally invasive procedure in which an occluding device is inserted via the femoral vessels without thoracotomy, and it is used as a standard treatment in infants, children, and adults. In preterm infants, approval of the Amplatzer Piccolo Occluder by the U.S. Food and Drug Administration in 2019 made this procedure feasible in infants weighing ≥700 g and aged ≥3 postnatal days, with improving short-term success rates and safety profiles [38]. However, evidence regarding whether this procedure can improve long-term clinical outcomes, particularly BPD and neurodevelopmental outcomes, remains insufficient [38]. Accordingly, transcatheter closure in preterm infants should be considered for preterm infants when repeated pharmacological treatment has failed or is contraindicated and when there are clinical symptoms and a large shunt is evident on echocardiography [17,18]. In Korea, the procedure has been performed under restricted indications since approval by the Korean Ministry of Food and Drug Safety in 2021, although outcomes data specific to preterm infants have not yet been reported.

Pharmacological treatment strategies for PDA can be classified according to the purpose and timing of administration into prophylactic treatment, early routine treatment, and selective or targeted treatment [1,10]. Prophylactic or early routine treatment was introduced based on the concept that ductal patency itself represents a major risk factor. Prophylactic treatment is administered in the early postnatal period regardless of the clinical symptoms or echocardiographic confirmation of PDA. Indomethacin was the first agent introduced for this purpose, followed by ibuprofen based on comparable efficacy and a more favorable safety profile, with paracetamol added more recently as a treatment option. In meta-analyses, all three agents have demonstrated higher ductal closure rates than placebo when used prophylactically [11,39,40]. In particular, indomethacin was used for many years after studies showed that it reduced the incidence of symptomatic PDA, surgical ligation, and severe intraventricular hemorrhage [11], although it did not reduce mortality, BPD, or long-term neurodevelopmental complications [41]. Furthermore, indomethacin is currently not available as a standard treatment option in Korea because of supply discontinuation.

Early treatment strategies involving routine attempts to achieve PDA closure during the early postnatal period, generally within the first 7 days of life immediately after PDA diagnosis, have also consistently failed to improve major clinical outcomes in recent randomized controlled trials and meta-analyses. Early ibuprofen treatment was not superior to conservative management for the composite outcome of NEC, BPD, and mortality [14], and it also failed to significantly reduce death or moderate-to-severe BPD at 36 weeks’ postmenstrual age [19]. Some studies have suggested that aggressive early treatment may even be associated with adverse clinical outcomes [20,21]. In particular, a recently published multicenter randomized controlled trial from the NICHD NRN was terminated early for safety reasons, as mortality in the active-treatment group was significantly higher than that in the expectant-management group at the interim analysis [20].

Based on this evidence, it is difficult to conclude that shortening the duration of ductal patency itself directly translates into improved clinical outcomes. Accordingly, a uniform early closure strategy should be applied with caution in light of current evidence. However, randomized controlled trial results should be interpreted with consideration of their methodological limitations. The BeNeDuctus trial was terminated early at approximately 48% of the planned sample size; the majority of enrolled infants were in relatively stable condition, and the ibuprofen regimen included repeated and high-dose administration compared with single standard-therapy studies, resulting in a higher cumulative dose in a considerable proportion of the study group [14]. In the Baby-OSCAR trial, approximately 30% of the placebo group received open-label treatment, including surgical ligation, before trial completion, which limits the conclusions that can be drawn regarding higher-risk subgroups [19].

Surgical ligation is generally considered when pharmacological treatment has failed or is contraindicated. The actual decision should be individualized, with comprehensive consideration of hemodynamic stability, respiratory status, bleeding risk, intestinal vulnerability, comorbidities, and echocardiographic findings. Furthermore, findings of systemic hypoperfusion, such as hypotension, metabolic acidosis, and oliguria, as well as signs of heart failure, such as increased oxygen requirement and pulmonary edema, may also be attributable to pathological processes other than PDA. Therefore, the decision to perform surgical ligation should not be based on these symptoms alone but should be made carefully by integrating the clinical course and echocardiographic assessment [17,18].

PDA may be statistically associated with pulmonary hemorrhage, intraventricular hemorrhage, NEC, BPD, and neurodevelopmental impairment in preterm infants. However, these clinical outcomes should not be attributed solely to the presence of a PDA, but should instead be understood in the context of overall illness severity and the effects of the treatment course.

PDA may contribute to the development of pulmonary edema and pulmonary hemorrhage through increased pulmonary blood flow and elevated pulmonary capillary pressure. This association is particularly relevant in extremely low birth weight infants, in whom pulmonary vascular resistance decreases abruptly after surfactant administration [3,9,12,22]. Some observational studies have reported an increased risk of pulmonary hemorrhage among infants who underwent surgical ligation; however, residual confounding by underlying illness severity cannot be excluded [37]. The efficacy of early ibuprofen treatment has also been reported to vary by gestational age. Although it was associated with a reduction in pulmonary hemorrhage at 26 to 27 weeks of gestational age, an increased risk of NEC at 24 to 25 weeks has also been reported, making it difficult to establish a consistent preventive effect.

Intraventricular hemorrhage and PDA share risk factors related to prematurity. PDA occurs in more than 70% of infants at 24 to 25 weeks of gestational age, and intraventricular hemorrhage occurs in approximately 45% of infants born before 25 weeks of gestation [12,22,26]. A large left-to-right ductal shunt may exacerbate cerebral blood flow instability by reducing diastolic cerebral perfusion [12,22,26]. Low blood pressure during the early postnatal period has also been associated with both an increased likelihood of surgical ligation and a higher risk of intraventricular hemorrhage [25].

Prophylactic indomethacin treatment may be associated with reduced intraventricular hemorrhage, but its benefit in improving long-term clinical outcomes such as neurodevelopmental impairment has not been clearly established [9,10,12]. Conversely, some studies have reported higher rates of severe intraventricular hemorrhage in the early closure group; however, these findings should be interpreted cautiously, considering the possibility that more aggressive treatment was preferentially applied to infants in worse clinical condition [42].

The relationship between NEC and PDA treatment has not been established as clearly causal [10,14,31]. Findings regarding pharmacological treatment have also been inconsistent. Ibuprofen has been reported to have closure efficacy comparable to that of indomethacin, with lower risks of renal injury and NEC [9,10,12,31]. Paracetamol, which has been increasingly used in recent years, may be associated with lower risks of NEC than ibuprofen, although evidence regarding long-term outcomes remains limited [9,10,43]. Both large left-to-right shunting and pharmacological treatment may affect mesenteric blood flow [31]; however, randomized controlled trials have shown that maintaining small-volume enteral feeding during ibuprofen treatment does not increase the incidence of NEC [44]. Therefore, the enteral feeding strategy during pharmacological treatment of PDA should be individualized according to the patient’s clinical status rather than uniformly withholding feeds.

The risk of BPD and associated pulmonary hypertension appears to increase primarily when moderate or greater hemodynamically significant PDA persists for 7 to 14 days or longer. This association is thought to be related to sustained increases in pulmonary blood flow, pulmonary edema, reduced pulmonary compliance, and impaired alveolar and pulmonary vascular development [45-48]. However, high rates of spontaneous closure, approximately 91%, have been reported even in extremely preterm infants managed conservatively, and the incidence of BPD also showed a tendency to decrease over time [33,49]. Therefore, rather than applying uniform early closure to reduce the risk of BPD, a selective treatment strategy that considers the persistence of hemodynamically significant PDA and the patient’s clinical status is warranted. Table 1 summarizes the major randomized controlled trials published over the past 10 years that compare the short-term efficacy of pharmacological closure versus conservative management of PDA [14,19-21,50-52].

With respect to neurodevelopmental outcomes, the patient’s overall clinical status and the selected treatment strategy appear to have greater influence than the presence of PDA itself. A Swedish extremely preterm infant cohort study with follow-up to 6.5 years of age reported that primary surgical ligation was associated with an increased risk of moderate-to-severe neurodevelopmental impairment and lower full-scale intelligence quotient (IQ) scores, with reductions in pontine and cerebellar vermis volumes observed in a subset of patients [53]. However, these findings warrant cautious interpretation, as it is difficult to distinguish the effects of baseline illness severity in infants who required surgical intervention from the potential independent effect of surgery itself on neurodevelopmental trajectories. Furthermore, while some retrospective studies have suggested an association between delayed PDA closure and lower developmental indices in infancy and early childhood, it cannot be ruled out that the severity of the underlying conditions associated with persistent PDA may have acted as confounding factors in these developmental outcomes [54,55].

The comparative effects of pharmacologic closure and conservative management on neurodevelopmental outcomes, as identified in randomized prospective studies, are also inconsistent. Early ibuprofen treatment did not improve survival free of moderate-to-severe neurodevelopmental impairment at 24 months of age [50,56]. In a Korean randomized controlled trial conducted in preterm infants of 23 to 26 weeks of gestation, conservative management showed no significant difference in the incidence of neurodevelopmental impairment at 2 years of age compared with oral ibuprofen treatment; moreover, a trend toward higher rates of motor impairment and hearing loss was observed in the treatment group [34].

The relationship between PDA and its associated complications may vary depending on the outcome domain examined. Pulmonary complications may be promoted by exposure to severe or persistent hemodynamically significant PDA through sustained pulmonary overcirculation, whereas neurodevelopmental outcomes are influenced by multiple mediating factors, including prematurity, severity of underlying illness, and concurrent treatments, making it difficult to isolate the independent contribution of PDA itself. Furthermore, as evidence linking PDA to morbidities is derived predominantly from observational studies, whereas evidence for treatment efficacy is based mainly on randomized controlled trials, direct comparisons between these two bodies of evidence are inappropriate. Nevertheless, the possibility that hemodynamically significant PDA contributes to complications in certain high-risk infants, including those at the limits of viability, cannot be excluded; accordingly, the results of ongoing clinical trials comparing early selective pharmacological treatment with conservative management in more severely affected patients should be awaited [57].

In summary, the currently available evidence is insufficient to conclude that aggressive, routine closure treatment improves clinical outcomes, including complication rates and long-term neurological prognosis, across the overall patient population. Treatment strategy must therefore be determined based on a cautious and individualized approach that considers each patient’s clinical status, rather than adherence to any specific intervention protocol [16,17,36].

Decisions regarding whether and how to treat PDA in preterm infants require weighing the expected benefits and potential risks of conservative management, pharmacological treatment, and procedural or surgical intervention according to each patient’s clinical status. If PDA persists, potential risks include hemodynamic instability, pulmonary overcirculation, and systemic hypoperfusion. Conservative management may reduce unnecessary medication exposure and procedure-related risks; however, the potential risks associated with ongoing hemodynamic imbalance cannot be excluded if hemodynamically significant PDA persists [2,27]. Pharmacological treatment may cause renal dysfunction and gastrointestinal adverse effects, whereas procedural and surgical interventions carry risks related to general anesthesia, in addition to potential postoperative complications such as cardiopulmonary compromise, vocal cord paralysis, and diaphragmatic paralysis [13]. Gestational age, birth weight, respiratory status, and the severity of comorbid conditions vary among individual patients, and the risk-benefit balance shifts accordingly. Therefore, no single optimal treatment strategy is universally applicable to all patients, and a tailored approach based on each patient’s clinical status is warranted [10,17].

As noted above, no treatment strategy has demonstrated consistent superiority in major clinical outcomes to date, and an independent causal relationship between PDA and major complications has not yet been established. This uncertainty in the evidence requires a more careful and individualized approach to treatment decision-making. Treatment decisions should be based on a comprehensive assessment integrating repeated clinical evaluations and echocardiographic findings rather than on any single parameter. Ideally, this process should involve multidisciplinary collaboration among relevant specialists, including neonatologists, pediatric cardiologists, and pediatric cardiac surgeons. However, such an approach may not be feasible in all clinical settings because of regional differences in the availability of consultants and healthcare resources. In clinical practice, therefore, treatment decisions should primarily rely on the clinical judgment of the neonatologist who has the most comprehensive understanding of the patient’s overall clinical course.

During treatment decision-making, clinicians should provide caregivers with a thorough explanation of the potential benefits and risks of each strategy, as well as the possibility of complications inherent to prematurity itself. However, given the limitations of prognostication in preterm infant care, caution is required when retrospectively inferring a causal relationship between specific past treatment decisions and the occurrence of unexpected complications or final clinical outcomes.

Uncertainty regarding the clinical significance of PDA in preterm infants and the optimal treatment strategy persists, and major international guidelines consistently do not support prophylactic or early routine treatment. Instead, they emphasize a selective approach based on each patient’s hemodynamic status and overall clinical context (Table 2).

The Canadian Paediatric Society’s 2022 position statement recognizes that PDA is associated with intraventricular hemorrhage, NEC, and BPD, but states that causality has not been established [18]. It recommends that treatment decisions integrate clinical symptoms with echocardiography-based hemodynamic assessment. Ibuprofen is recommended as the first-line therapy for symptomatic PDA, whereas conservative management may be considered in clinically stable preterm infants at 1 to 2 weeks of postnatal age, with caution advised in unstable extremely preterm infants born before 26 weeks of gestation. It further suggests that procedural closure should be considered only under restricted conditions and that infants with persistent PDA after discharge should be referred to a pediatric cardiologist for follow-up.

The 2025 American Academy of Pediatrics clinical report states that prophylactic or early routine treatment of PDA does not improve major clinical outcomes, including mortality, BPD, and neurodevelopmental impairment, and therefore is not recommended [17]. It also notes that, even in hemodynamically significant PDA, the relative benefits of conservative management, pharmacological treatment, and procedural closure remain unclear, making it difficult to draw definitive conclusions regarding whether and how treatment should be pursued. The report further states that evidence remains insufficient to provide firm recommendations regarding management beyond 2 weeks of postnatal age, although up to two courses of pharmacological treatment followed by transcatheter closure or surgical ligation may be considered as potential treatment options. The specific recommendations are summarized below.

In summary, current North American guidelines acknowledge the association between PDA and various complications of prematurity and neurodevelopmental impairment, while consistently noting that evidence remains insufficient to demonstrate that treatment can prevent or improve these outcomes. In particular, recent evidence emphasizes understanding PDA as a biomarker reflecting the severity of underlying disease and adverse clinical outcomes in preterm infants, rather than as an independent determinant of neurological outcomes such as intraventricular hemorrhage [15,17,20]. Accordingly, aggressive intervention, including procedural closure, should be reserved for selected patients with clear indications, and temporal and causal relationships between PDA, its treatment, and potential complications should be interpreted with caution.

The provision of care for PDA in preterm infants in Korea remains uneven due to disparities in medical resources across institutions and regions. In particular, differences in access to surgical and procedural treatment, availability of specialized personnel, and diagnostic support systems such as echocardiography may lead to delays in multidisciplinary consultation, difficulties in patient transfer, and constraints on decisions regarding treatment timing. These factors suggest that PDA treatment outcomes may be influenced not only by clinical judgment but also by the healthcare environment and system.

A survey conducted among members of the Korean Society of Neonatology in April 2026 identified several critical gaps in the current domestic healthcare system [58]. Regarding surgical accessibility, only approximately half of the more than 90 neonatal intensive care units registered with the Health Insurance Review and Assessment Service had the capacity to perform PDA surgery on-site. Even among larger institutions with 40 or more beds, only 76.7% had on-site surgical capability, and only 57.6% had a pediatric cardiac surgeon. Multidisciplinary diagnostic capacity was also limited: although 86.7% of institutions had access to a pediatric cardiology subspecialist, coverage during nighttime hours and on public holidays remained insufficient. These findings indicate that a substantial proportion of PDA diagnosis and treatment decision-making is concentrated among neonatologists, highlighting the urgent need for staffing support and systematic improvements in training for high-complexity diagnostic capacity.

Addressing these structural challenges will require the development of regional care coordination networks, strengthening of multidisciplinary collaboration, support for essential diagnostic personnel, and establishment of legal and institutional safeguards that reflect the realities of actual clinical practice. These tasks must be pursued systematically at the national level, beyond the scope of any single institution, and the relevant status should continue to be monitored and reported through the Korean Society of Neonatology.

PDA in preterm infants represents a complex clinical entity on the continuum between physiological adaptation and pathological disease. Current evidence is insufficient to establish definitive causal relationships between PDA and its associated complications or long-term outcomes. Despite more than half a century of accumulated research and debate, no treatment strategy has yet been established as a universal standard of care across all patients. Therefore, the optimal treatment strategy should be tailored according to each patient’s clinical status and hemodynamic characteristics. Although multidisciplinary discussion should inform decision-making, the clinical judgment of the neonatologist with the most comprehensive understanding of the patient’s clinical course should remain central to this process.

In the future, the healthcare system must move beyond the mere formulation of treatment guidelines toward a more comprehensive approach encompassing the healthcare system as a whole. This should include efforts to reduce interregional disparities in access to care, expand the specialist workforce, and establish efficient patient transfer systems. Ultimately, improving the quality of PDA care depends not on the selection of a particular treatment strategy, but on establishing a rational decision-making framework that reflects the heterogeneity of patient presentations and is supported by a healthcare system capable of sustaining it.