What is the aetiology ?
An aberrant right subclavian artery results from involution of the entire right fourth embryonic arch with persistence of the right seventh intersegmental artery which gives rise to the right subclavian artery.
What is the clinical presentation?
Affected patients are typically asymptomatic adults. Patients with associated right ligament arteriosus have a complete vascular ring and may have symptoms. In addition, symptoms of tracheal compression have been described in affected children, particularly those with associated common origin with the carotid arteries. In these cases, the aberrant vessel has been called arteria lusoria and the symptom dysphagia lusoria.
What is the clinical implication in relation to cardiac catheterisation?
An aberrant right subclavian artery is a significant incidental finding in patients who undergo cardiac catheterisation through the right arm as the catheter typically enters the descending aorta and cannot be manoeuvred into the ascending aorta.
What do you know about diverticulum of Kommerell?
Diverticulum of Kommerell was first described on an oesophagram of an asymptomatic patient with a left aortic arch and an aberrant right subclavian artery with a diverticulum at its origin which produced mass effect on the oesophagus. Interestingly, the aortic diverticulum occurs more frequently in patients with right aortic arch and aberrant left subclavian artery. It may be congenital or secondary to atherosclerotic dilatation.
Aberrant right subclavian artery arising from the distal posterior aortic arch and coursing superiorly and to the right behind the trachea and oesophagus.