The right subclavian artery vagus is a congenital arteriovenous malformation that does not recover on its own. During normal embryonic development, the ascending aortic arch sends out branches of the right and left common carotid artery and subclavian artery, and later the right subclavian artery and the left common carotid artery converge and then form a vessel. However, if the confluence of the right subclavian artery and the left common carotid artery is impaired for various reasons during fetal life, a failure of confluence occurs and the right subclavian artery is left behind, which is called right subclavian artery vagalization. This is a vascular malformation that cannot recover on its own, but it is a benign change that rarely presents with adverse symptoms. If the heart structure or other vascular alignment is found to be fine after examination, it usually does not affect growth and development. Patients are advised to observe closely in general and no special intervention is needed, but if obvious discomfort symptoms such as respiratory distress occur, surgical treatment may be required if necessary.