Does the vertebral artery originate from the subclavian artery?

Vertebral Artery Origin from the Subclavian Artery

Yes, the vertebral artery typically originates from the subclavian artery as its first branch, though anatomical variants exist in approximately 5-7% of individuals. 1, 2

Normal Anatomy

• The vertebral arteries usually arise from the subclavian arteries bilaterally as the first branch of each subclavian artery 1, 3
• The right vertebral artery originates from the right subclavian artery, and the left vertebral artery originates from the left subclavian artery in the typical anatomical configuration 4
• After originating from the subclavian artery, the vertebral artery is divided into four segments (V1-V4), with the first three segments being extracranial 1, 3

Common Anatomical Variants

Left Vertebral Artery Variants

• In approximately 5-7% of individuals, the left vertebral artery arises directly from the aortic arch rather than from the left subclavian artery 1, 2
• When this variant occurs, the left vertebral artery typically arises from the arch between the left carotid and left subclavian arteries 1
• This represents the most common anatomic variant for the left vertebral artery 1

Right Vertebral Artery Variants

• Anatomical variation in the origin of the right vertebral artery is rare compared to left-sided variants 4
• The right vertebral artery can arise from the right common carotid artery in rare cases 4

Bilateral Variants

• Extremely rare cases exist where both vertebral arteries arise from atypical locations, such as the descending thoracic aorta distal to the left subclavian artery 5

Clinical Significance

• Recognition of vertebral artery origin variants is critical during aortic repair procedures to prevent inadvertent coverage or injury of aberrant vertebral arteries 1
• When the left vertebral artery arises directly from the aortic arch and requires coverage during thoracic endovascular aortic repair (TEVAR), revascularization of the vertebral artery is reasonable to reduce risk of stroke and spinal cord ischemia 1
• Adequate identification of vertebral artery anomalies in preoperative imaging is essential to avoid misdiagnosed vertebral occlusions or unexpected vertebral artery injuries during neck, thyroid, esophageal, or endovascular procedures 5