Initial Treatment for Patent Ductus Arteriosus in a Term Infant
In a term infant with a hemodynamically significant PDA, transcatheter device closure is the preferred treatment approach, with surgical closure reserved only for cases where the PDA is too large for device closure or anatomy is unsuitable. 1
Diagnostic Confirmation Before Treatment
Before initiating any treatment, confirm the diagnosis and assess hemodynamic significance through:
- Echocardiography with color Doppler in the parasternal short-axis view 1, 2
- Measurement of transpulmonary gradient using continuous-wave Doppler to estimate pulmonary artery pressure 1
- Assessment for left atrial and/or left ventricular enlargement, which indicates hemodynamic significance 1, 2
- Cardiac catheterization if significant elevation of pulmonary vascular resistance is suspected or echocardiography is non-diagnostic 1
Indications for Closure in Term Infants
Closure is recommended when any of the following are present:
- Left atrial and/or left ventricular enlargement attributable to PDA with net left-to-right shunt 1, 2
- Pulmonary arterial hypertension with net left-to-right shunting 1
- Prior history of endarteritis 1
The American College of Cardiology suggests it is reasonable to close even small asymptomatic PDAs by catheter device 1, though this remains somewhat controversial in clinical practice.
Treatment Approach: Device Closure First-Line
Device closure via transcatheter approach is the method of choice for term infants and older children with suitable anatomy 1, 2. This approach is particularly important because:
- Standard practice includes administration of 50-100 U/kg unfractionated heparin at the time of device implantation 1
- Success rates exceed 95% with transcatheter closure 3
- Complete closure approaches 100% in late-term follow-up 3
- The AMPLATZER Duct Occluder (FDA-approved in 2003) can close PDAs as large as 16 mm with no long-term residual shunting 3
When Surgical Closure is Indicated
Surgical closure should only be performed when:
- PDA is too large for device closure 1
- Distorted ductal anatomy precludes device closure 1
- Concomitant cardiac surgery is required for other indications 1
When surgery is necessary:
- It should be performed by a surgeon experienced in congenital heart disease surgery 1
- Surgical success rate exceeds 95% with low early mortality 1
- Recanalization is rare after surgical closure 1
- Consultation with ACHD interventional cardiologists is recommended before selecting surgical closure, especially in cases with a calcified PDA 1
Absolute Contraindication
PDA closure is contraindicated in patients with pulmonary arterial hypertension and net right-to-left shunt (Eisenmenger physiology) 1
Important Distinction: Term vs. Preterm Infants
The question specifically asks about term infants, where the management differs significantly from preterm infants:
- Pharmacological therapy with NSAIDs (indomethacin, ibuprofen) is NOT the initial treatment for term infants 1, 4
- NSAIDs are primarily used in preterm/very low birth weight infants for medical closure 1, 4, 5
- In term infants, the PDA is typically diagnosed later and requires definitive closure rather than medical therapy 1
Follow-Up After Closure
- After successful closure, patients can be discharged from follow-up once complete closure is documented by transthoracic echocardiography 1
- For small PDAs without left-heart volume overload that are being observed, routine follow-up every 3 to 5 years is recommended 1
Common Pitfall to Avoid
Do not confuse the management of PDA in term infants with that in preterm infants. The evidence on NSAIDs (ibuprofen, indomethacin) applies primarily to preterm populations 4, 6, 7, 8, 5, 9, whereas term infants with hemodynamically significant PDA require interventional or surgical closure as the definitive treatment 1.