A comprehensive analysis of patent ductus arteriosus (PDA) management in extremely preterm infants reveals that transcatheter closure offers comparable respiratory outcomes to traditional surgical approaches while potentially providing additional benefits for pulmonary edema resolution.
Comparable Respiratory Outcomes Between Treatment Methods
Research published in JAMA Network Open examined 561 extremely preterm infants born at less than 29 weeks' gestation or weighing less than 1000 grams who underwent definitive PDA closure between 2016 and 2020. The study compared outcomes between 202 infants who received transcatheter closure and 359 who underwent surgical ligation.
The primary finding showed no significant difference in total mechanical ventilation days between the two approaches. After adjusting for center, birth year, gestational age, age at intervention, and prior pharmacologic treatment, the adjusted mean difference was −2.65 days (95% CI, −8.36 to 3.07, P = .36). Median total ventilation days remained identical at 46 days for both groups.
Notably, infants undergoing transcatheter closure were older at the time of intervention, with a mean age of 58.7 days compared to 33.6 days for surgical patients (P < .001). This age difference reflects evolving clinical practices and device availability considerations.
Radiographic Evidence of Pulmonary Improvement
A separate study from Riley Hospital for Children provided detailed analysis of chest X-ray changes following transcatheter PDA closure in 68 preterm infants. Using the validated Radiographic Assessment of Lung Edema (RALE) score, researchers found that 59% of patients showed decreased pulmonary haziness after the procedure.
The study revealed that 16.4% of patients experienced clinically significant improvement, defined as a RALE score decrease of at least 16 points. This improvement was most pronounced in infants with hemodynamically significant PDAs, who showed an average RALE score improvement 8 points greater than those without significant shunting (P < 0.05).
Patient Characteristics Predict Treatment Response
The Riley Hospital study identified specific patient characteristics associated with optimal outcomes from transcatheter closure. Infants born more prematurely showed greater improvement in RALE scores, with an average change of 5.2 points compared to older infants. Those with significant radiographic improvement were more likely to weigh between 1,000-2,000 grams at closure and were younger by approximately 0.8 months.
Patients with larger indexed PDA/body surface area ratios, higher echocardiographic McNamara scores, and less severe chronic lung disease demonstrated greater improvements. Conversely, infants with advanced chronic lung disease showed less benefit, likely because the PDA was not the primary driver of their respiratory symptoms.
Clinical Respiratory Status Changes
Within one week of transcatheter closure, 40% of patients in the Riley Hospital cohort were able to reduce their respiratory support requirements, while only 3% required increased support. This contrasted with post-procedure day 1, when 10% of patients initially required increased respiratory support.
The study noted that 54% of patients maintained similar respiratory support levels before and after the procedure, which researchers attributed to persistent critical illness and underlying lung pathology despite successful PDA closure.
Safety Profile and Complications
Both studies reported acceptable safety profiles for transcatheter closure. The Riley Hospital study documented complications in 9% of patients, including one case of MSSA bacteremia and one mortality. Inotrope initiation or increase was required in 3% of patients on post-procedure day 1 and 6% by day 7.
These complication rates align with previous research showing that transcatheter closure may offer advantages over surgical ligation in terms of post-procedural support requirements.
Device Technology and FDA Approval
The increasing adoption of transcatheter PDA closure has been facilitated by technological advances and regulatory approvals. In 2019, the FDA approved the Amplatzer Piccolo Occluder for use in premature infants weighing more than 700 grams as early as postnatal day 3.
The Riley Hospital study utilized various devices, with the Amplatzer Piccolo Occluder used in 52.2% of cases, followed by Medtronic Microvascular Plug (31.8%) and other devices. A previous clinical trial of the Amplatzer Piccolo Occluder demonstrated a 95.5% implant success rate and 99.4% achievement of primary effectiveness endpoints.
Clinical Decision-Making Considerations
The research supports the use of hemodynamic significance scoring systems to guide treatment decisions. The Riley Hospital study employed a modified McNamara Scale, finding that only the echocardiographic component was associated with improvement, while clinical scores may be falsely elevated in patients with other comorbidities.
These findings suggest that transcatheter PDA closure represents a viable alternative to surgical ligation, particularly for infants with hemodynamically significant shunts. The comparable respiratory outcomes, combined with potential advantages in pulmonary edema resolution and procedural invasiveness, support the growing adoption of transcatheter approaches in appropriate candidates.
