A Novel Case of Anomalous Origin of Left Vertebral Artery Associated With Left Subclavian Steal Syndrome

The subclavian steal syndrome (SSS) is defined by the reversal of flow in the ipsilateral vertebral artery in the setting of subclavian artery stenosis proximal to its origin. Here, we describe a rare case of left SSS with significant left subclavian artery stenosis associated with anomalous origin of the left vertebral artery (LVA) directly from the aortic arch in a patient presenting with signs of vertebrobasilar insufficiency and resolution of symptoms following angioplasty. Through this case, the authors try to emphasize the importance and the correct technique of using Doppler ultrasonography, and the importance of invasive angiography in understanding the mechanism of subclavian steal in patients with anomalous LVA origin.