General
Paired veins of the superior mediastinum that drains the upper limbs, head and neck.
Origin
Confluence of subclavian vein and internal jugular vein (termed the venous angle), posterior to the sternoclavicular joints on either side.
Course
- Both brachiocephalic veins course toward the midline.
- The left brachiocephalic vein courses obliquely across the 1st part of the left subclavian artery, left common carotid artery and right brachiocephalic trunk.
- The right brachiocephalic vein has a shorter more vertical course.
- Both unite posterior to the inferior border of the 1st right costal cartilage to form the superior vena cava, which empties into the right atrium.
Relations
- Posteriorly: subclavian artery, left common carotid, right brachiocephalic trunk, left internal thoracic artery, left vagus, left phrenic nerve.
- Anteriorly: manubrium of the sternum, thymus gland, sternohyoid and sternothyroid muscles. Distally, costal cartilage of right 1st rib.
- Inferiorly: aortic arch (to left brachiocephalic vein)
Tributaries
Right brachiocephalic vein
- Right vertebral vein – formed in the suboccipital triangle, drains deep muscles of posterior neck
- Inferior thyroid vein – drains thyroid
- Right internal thoracic vein – drains chest wall and breasts
- Right superior intercostal vein
Left brachiocephalic vein
- Left vertebral vein
- Inferior thyroid vein – drains thyroid
- Left internal thoracic vein – drains chest wall and breast
- Supreme intercostal vein – drains first intercostal space. Valveless.
- Thymic veins
- Pericardiophrenic veins – drains superior diaphragm and pericardium
(Note: The superior thyroid and middle thyroid vein drain into the internal jugular vein)
Variants
- Retroaortic left brachiocephalic vein
- Absent or hypoplastic
- Duplicated SVC