What is the first branch of the subclavian artery?

The first branch of the subclavian artery is the vertebral artery, which originates from the subclavian artery on each side, typically just after the artery emerges from the aortic arch on the left and from the brachiocephalic trunk on the right. The vertebral artery ascends through the foramina in the transverse processes of the cervical vertebrae and contributes to the vascular supply of the brain, particularly the posterior portion.

Understanding the role of the vertebral artery is crucial, as it is a key vessel in the circulation of blood to the brain and can be involved in various clinical scenarios such as vertebrobasilar insufficiency. The anatomy of the subclavian artery and its branches is an essential aspect of vascular ultrasound assessments, as it aids in evaluating blood flow and detecting abnormalities.

The other options do not represent the first branch of the subclavian artery. The cervical artery is not a standard term typically used in vascular anatomy in this context, the sublingual artery branches off from the lingual artery rather than the subclavian artery, and the internal thoracic artery also arises from the subclavian artery but after the vertebral artery. Thus, identifying the vertebral artery as the first branch emphasizes its