What is the treatment for an aberrant right subclavian artery?

Treatment of Aberrant Right Subclavian Artery

For patients with aberrant right subclavian artery (ARSA), surgical intervention is recommended when the patient is symptomatic or when associated with a Kommerell's diverticulum that has an orifice >3.0 cm or a combined diameter with adjacent descending aorta >5.0 cm. 1

Diagnostic Evaluation

• ARSA is usually detected incidentally on CT of chest/neck ordered for other reasons 2
• When ARSA is discovered without thoracic aortic imaging, dedicated imaging (CT or MRI) to assess for thoracic aortic aneurysm is reasonable (Class 2a recommendation) 2, 1
• CMR provides advantages for assessment including airway imaging to guide therapeutic management 2
• Measurements needed:
  • Diverticulum orifice diameter
  • Combined diameter of diverticulum and adjacent descending aorta 2

Treatment Algorithm

Asymptomatic Patients

1. Without Kommerell's diverticulum:

   • Observation with regular imaging surveillance 3
   • Monitor for development of symptoms or aneurysmal changes 1

2. With Kommerell's diverticulum:

   • Repair recommended when:
     • Diverticulum orifice >3.0 cm, OR
     • Combined diameter of diverticulum and adjacent descending aorta >5.0 cm 2, 1
   • Annual growth rate of 3.05 mm at 1 cm distal to vessel ostium may help guide surveillance timing 3

Symptomatic Patients

• Urgent referral to cardiovascular surgeon or interventional radiologist 1
• Common symptoms requiring intervention:
  • Dysphagia (most common - 30%) 3
  • Respiratory symptoms
  • Recurrent laryngeal nerve palsy 2

Surgical Approaches

1. Open Surgical Repair:

   • Resection of aneurysmal segment with graft replacement 1
   • Can be performed entirely via supraclavicular approach in select cases without aneurysmal degeneration 4

2. Endovascular Approach:

   • Exclusion of right subclavian artery origin and adjacent aorta using aortic endograft 1, 5
   • Lower reported hospital stay (average 5.4 days) 5

3. Hybrid Approach (most common - 54% of interventions):

   • Combination of:
     • Right carotid-subclavian bypass or transposition
     • Thoracic endovascular aortic repair 3
   • Appears feasible, safe, and effective for ARSA with Kommerell's diverticulum 5

Post-operative Care and Follow-up

• Regular cardiovascular imaging to monitor:
  • Endoleaks (reported in 13% of endovascular cases) 5
  • Aneurysm size reduction (reported 25-50% decrease) 5
  • Development of new symptoms 1

Complications to Monitor

• Endoleaks (Type I, II, or IV)
• Perioperative mortality (reported 10% in hybrid repairs) 5
• Other postoperative complications (reported in 22% of endovascular cases) 5

The presence of Kommerell's diverticulum strongly correlates with need for intervention, with studies showing 100% of patients with this feature requiring treatment for symptoms or aneurysmal degeneration 6.