Relations

The aorta has the following relations during its course posteriorly and to the left:

• anterior: left brachiocephalic vein superior to thymus and left anterior mediastinal pleura
• left lateral surface, from anterior to posterior:
  • left phrenic nerve
  • cardiac branches of sympathetic nerve
  • left superior intercostal vein
  • left vagus nerve
• left posterolateral surface, from anterior to posterior:
  • superior vena cava
  • trachea
  • left recurrent laryngeal nerve in tracheo-oesophageal groove
  • oesophagus
  • thoracic duct
• inferiorly:
  • left recurrent laryngeal nerve
  • ligamentum arteriosum
  • aortic bodies
  • pulmonary trunk and left pulmonary artery
  • left principal bronchus
• superior:
  • anteriorly, the left brachiocephalic vein
  • branches of aortic arch

The relationship of structures to the aortic arch within the superior mediastinum provides one way of systematically dividing this compartment.