Left subclavian artery
Branch · 3rd arch branch VIT C&D
Third arch branch, arising from the arch itself (the right subclavian arises from the brachiocephalic trunk). Arches over the cervical pleura and first rib, divided into three parts by scalenus anterior, and becomes the axillary artery at the lateral border of the first rib. Branches: vertebral, internal thoracic, thyrocervical trunk, costocervical trunk, dorsal scapular.
Traced from the start
- Arch of the aorta
- Left subclavian artery
Detail
- Branches
- Vertebral, Internal thoracic, Thyrocervical trunk, Costocervical trunk, Dorsal scapular (VIT C&D)
- Costocervical trunk
- Gives the supreme intercostal artery for the 1st and 2nd intercostal spaces; the aorta supplies the rest
- Continues as
- Axillary artery at the lateral border of the first rib
When it goes wrong
Subclavian stenosis proximal to the vertebral origin
Subclavian steal: with arm exercise flow reverses down the ipsilateral vertebral artery, giving arm claudication with dizziness or syncope and a systolic pressure difference of more than 15 mmHg between the arms
Cervical rib or thoracic outlet compression over the first rib
Post-stenotic dilatation and arm claudication; radial pulse fades on Adson's manoeuvre
Practise this structure
1 question in the bank tagged Arterial Supply.