Dizziness due to Subclavian Steal
Prepared by: Dr.Samar Esam
Anatomy of the Subclavian arteries from normal imaging:
The vertebral arteries begin in the neck generally taking their origin from the subclavian arteries or the brachiocephalic trunk (combination of carotid and subclavian together) on both sides R&L .
they next enter the bones of the neck (vertebrae) at C5-C6, and then ascend upward through holes in the bones called “transverse foramina”. Between the top 2 vertebrae, C2 and C1, the vertebral arteries move laterally.
This is where they make a jog to the side on the picture above. Next they enter the skull, and eventually join together to form the basilar artery that supplies the brainstem and cerebellum.
In the subclavian steal syndrome, due to stenosis of the subclavian artery, blood may be supplied to the arm retrograde flow in the vertebral artery. This causes asymmetry in the radial pluse & blood pressure between both side provoked by arm exercises and also causes brainstem symptoms due to low blood flow in the vertebral artery.
They may include paroxysmal vertigo, drop attacks , fluctuating bil H.L , tinnitus symptoms may resemble like Meniere’s disease are provoked by exercise.
References:
- Fanari, Z., et al. (2014). “High-risk acute coronary syndrome in a patient with coronary subclavian steal syndrome secondary to critical subclavian artery stenosis.” Case Rep Cardiol 2014: 175235.
- Kilic, I. D., et al. (2015). “Coronary subclavian steal syndrome: a case-based review.” Herz 40(2): 250-254.
- Osiro, S., et al. (2012). “A review of subclavian steal syndrome with clinical correlation.” Med Sci Monit 18(5): RA57-63.
- Psillas, G., et al. (2007). “Subclavian steal syndrome: neurotological manifestations.” Acta Otorhinolaryngol Ital 27(1): 33-37.
- Redmond, K. C., et al. (2002). “Bilateral subclavian steal syndrome.” Ir J Med Sci 171(1): 44-45.
