What is the management approach for an infant with hypoplastic aortic arch and pulmonary arterial hypertension (PAH)?

Management of Hypoplastic Aortic Arch with Pulmonary Arterial Hypertension in Infants

Infants with hypoplastic aortic arch and pulmonary arterial hypertension (PAH) require early surgical correction of the aortic arch obstruction followed by targeted management of PAH to optimize outcomes and reduce mortality.

Initial Assessment and Stabilization

• Echocardiographic evaluation is essential for:

  • Determining severity of arch hypoplasia
  • Assessing PAH severity
  • Evaluating for associated cardiac defects
  • Measuring right ventricular function

• Pre-operative stabilization:

  • Maintain ductal patency with prostaglandin E1 if needed for systemic perfusion 1
  • Optimize oxygenation targeting saturations 92-95% 2
  • Treat respiratory distress and optimize ventilation
  • Monitor for signs of right heart failure

Surgical Management

• Early surgical intervention is recommended for aortic arch hypoplasia to prevent progressive PAH

• Preferred surgical approaches:

  • Aortic arch advancement via median sternotomy for significant arch hypoplasia 3, 4
  • Extended end-to-end anastomosis for coarctation with arch hypoplasia 5
  • One-stage repair is preferred over two-stage approach when feasible 6

• Timing considerations:

  • Neonatal repair (within first month) shows better outcomes 4
  • Delay increases risk of irreversible PAH development

Management of PAH

Pre-operative PAH Management

• Inhaled nitric oxide (iNO) is indicated for:

  • Reducing need for ECMO support 1
  • Improving oxygenation in severe PAH
  • Initial dosing at 10-20 ppm with weaning to 2-10 ppm 2

• Sildenafil may be considered as adjunctive therapy for infants with PAH refractory to iNO, especially with oxygenation index >25 1

Post-operative PAH Management

• Cardiac catheterization is recommended before initiating long-term PAH therapy to:

  • Assess disease severity
  • Evaluate for contributing factors (LV dysfunction, shunts, pulmonary vein stenosis) 1

• PAH-targeted therapy options:

  • PDE5 inhibitors (sildenafil 0.5-2 mg/kg three times daily) 2
  • Endothelin receptor antagonists
  • Prostacyclin analogs for severe PAH 1

• Supplemental oxygen therapy to maintain saturations between 92-95% 1, 2

Monitoring and Follow-up

• Serial echocardiograms:

  • Every 2-4 weeks after initiation of PAH therapy
  • Every 4-6 months with stable disease 1, 2

• Monitor for complications:

  • Recurrent arch obstruction (occurs in 3-14% of cases) 4
  • Progressive PAH despite surgical correction
  • Right ventricular dysfunction
  • Pulmonary vein stenosis

• Follow in an interdisciplinary pediatric pulmonary hypertension program 1

Special Considerations

• Extracorporeal membrane oxygenation (ECMO) is indicated for:

  • Term and near-term infants with severe PAH refractory to iNO
  • Patients with oxygenation index >25 despite optimization of therapy 1

• Lung recruitment strategies can improve efficacy of iNO therapy 1

• Evaluate for pulmonary vein stenosis if PAH worsens despite appropriate management 1

Prognosis

• Early surgical correction with appropriate PAH management significantly improves outcomes
• Mortality is higher with associated complex cardiac lesions
• Long-term survival depends on severity of PAH and response to therapy
• Reintervention rates for arch obstruction are approximately 3-14% 6, 4

The management of hypoplastic aortic arch with PAH requires a coordinated approach between cardiac surgery, cardiology, and pulmonary hypertension specialists to optimize outcomes in these challenging patients.