What is the management of hypoplastic aortic arch?

Management of Hypoplastic Aortic Arch

Surgical intervention is the definitive treatment for hypoplastic aortic arch, with the specific approach determined by the anatomy, severity, and associated cardiac defects. 1

Diagnostic Evaluation

• Initial imaging should include TTE with suprasternal notch acoustic windows 1
• Complete evaluation requires at least one cardiovascular MRI or CT scan of the thoracic aorta and intracranial vessels 1
• Measurement consistency is crucial, using cardiac-gated CT or MRI with centerline measurement technique for accurate assessment of growth rates 2

Surgical Management Options

Based on Anatomical Considerations:

1. Isolated Hypoplastic Arch

   • Open surgical replacement at an arch diameter ≥5.5 cm for asymptomatic patients 1
   • Earlier intervention (≥5.0 cm) for patients with bicuspid aortic valve 2
   • Hemiarch replacement when aneurysmal disease extends into proximal aortic arch 1

2. Hypoplastic Arch with Coarctation

   • Extended end-to-end anastomosis - preferred for infants with coarctation and severe tubular hypoplasia of the transverse arch 3
   • Resection with posterior end-to-end anastomosis and anterior subclavian flap enlargement - for specific anatomical variants 4
   • Direct side-to-end anastomosis between ascending and descending aorta through median sternotomy - for complex cases 4

3. Complex Cases with Intracardiac Defects

   • Complete repair via sternotomy with core cooling and circulatory arrest 5
   • Consider isolated myocardial perfusion during arch repair to reduce myocardial ischemic time 5

4. Adult Patients with Hypoplastic Arch and Atypical Coarctation

   • Ascending aorta-lower abdominal aorta bypass grafts rather than conventional resection and anastomosis 6

Timing of Intervention

• Symptomatic patients with low/intermediate operative risk: immediate open surgical replacement 1
• Asymptomatic patients with isolated arch aneurysm: surgical replacement at ≥5.5 cm 1
• High-risk patients: consider hybrid or endovascular approach 1
• Special populations:
  • Bicuspid aortic valve: intervention at ≥5.0 cm 2
  • Marfan syndrome: intervention at 4.0-5.0 cm 2
  • Loeys-Dietz syndrome: intervention at ≥4.2 cm (internal) or ≥4.4-4.6 cm (external) 2

Medical Management

• Beta blockers as first-line therapy to reduce aortic wall stress (target heart rate ≤60 bpm) 2
• If systolic BP remains >120 mmHg after heart rate control, add ACE inhibitors 2
• Blood pressure target: <140/90 mmHg 2
• Regular moderate aerobic exercise recommended, but avoid strenuous isometric exercise and contact sports 2

Follow-up Protocol

• Lifelong cardiology follow-up required for all patients with aortic coarctation (repaired or not) 1
• Post-repair evaluation: at least yearly follow-up 1
• Imaging surveillance based on aortic diameter:
  • 3.0-3.4 cm: Every 3 years
  • 3.5-4.4 cm: Every 12 months
  • 4.5-5.4 cm: Every 6 months
  • ≥5.5 cm: Consider surgical intervention 2
• Late postoperative thoracic aortic imaging to assess for aortic dilatation or aneurysm formation 1
• MRI/CT evaluation of repair site at intervals of 5 years or less 1

Special Considerations

• Screening of family members is recommended for patients with bicuspid aortic valve 1
• Pregnancy management: caesarean delivery if aortic root diameter is ≥4.5 cm; joint cardiac and obstetric management with regular echocardiograms 2
• Recurrent coarctation (gradient ≥20 mm Hg) may occur in approximately 10% of cases, requiring reoperation or percutaneous angioplasty 3, 4

The surgical approach should be individualized based on the specific anatomical features, with the goal of optimizing long-term outcomes and minimizing the risk of recurrent obstruction.