Management of Left Aortic Arch with Aberrant Right Subclavian Artery
Initial Evaluation
- Dedicated thoracic aortic imaging with CT or MRI is reasonable for all patients discovered to have an ARSA, as this anomaly is associated with thoracic aortic aneurysm (TAA) in 2-8% of cases 1, 2
- Assess for symptoms of compression, which may include dysphagia, respiratory symptoms, or recurrent laryngeal nerve palsy due to the aberrant vessel coursing behind the esophagus 1, 3
- Evaluate for the presence of Kommerell's diverticulum, a persistent remnant of the fourth primitive dorsal aortic arch that may be present in 20-60% of patients with an aberrant subclavian artery 1, 4
Measurement Criteria
- Two key diameter measurements should be obtained using cross-sectional imaging The diverticulum orifice (measured radially and longitudinally at the aortic wall) 1
- The combined diameter of the diverticulum and adjacent descending thoracic aorta (measured from the tip of the diverticulum to the opposite aortic wall) 1
Management Algorithm
- The American College of Cardiology recommends surgical or endovascular intervention when the Kommerell's diverticulum orifice is >3.0 cm, the combined diameter of the diverticulum and adjacent descending aorta is >5.0 cm, or when the patient is symptomatic 1, 2
- For asymptomatic patients with Kommerell's diverticulum meeting size criteria, repair may be reasonable depending on patient anatomy and comorbidities 1, 2
Intervention Options
- Endovascular approaches may be appropriate depending on patient anatomy and comorbidities 1
- The choice of approach should be based on patient-specific factors including anatomy, comorbidities, and institutional expertise 1, 4