Superior mediastinum
Muscles origins of the Sternohyoidei and Sternothyreoidei / lower ends of the Longi colli
aortic arch
brachiocephalic artery
thoracic portions of the left common carotid and the left subclavian
brachiocephalic veins and upper half of the superior vena cava
left highest intercostal vein
vagus nerve
cardiac nerve
superficial and deep cardiac plexuses
phrenic nerve
left recurrent laryngeal nerve
trachea with paratracheal and tracheobronchial lymph nodes
esophagus
thoracic duct
remains of the thymus
some lymph glands
anterior longitudinal ligament