Completely Reversed Flow in the Vertebral Artery Does Not Always Indicate Subclavian Steal Phenomenon

Waveform Patterns and Peak Reversed Velocity in Vertebral Arteries Predict Severe Subclavian Artery Stenosis and Occlusion

“…In previous studies, PRV was used to determine the differential diagnosis of reversed flow in the VA (Chen et al 2013(Chen et al , 2014. In the present study, the PRV was significantly higher in SA occlusion cases than in severe SA stenosis cases, suggesting that SA occlusion occurs in patients with a higher PRV.…”

“…The resistance index was also calculated from the VA antegrade flow measurements. PRV represents the value from baseline to the reversed systolic peak and was measured as previously described (Chen et al 2014). As illustrated in Figure 2a-c, the measurements were acquired on waveforms that could be reproduced for at least three consecutive heartbeats.…”

“…The spectral Doppler waveform of the VA has also proven useful for predicting the degree of ipsilateral SA stenosis and determining if blood flow is antegrade or retrograde (Buckenham and Wright 2004;Kaneko et al 1998;Kliewer et al 2000;Sakima et al 2011). In previous studies, VA peak reversed velocity (PRV) has been used to determine the cause of reversed flow (Chen et al 2013(Chen et al , 2014. However, the correlation between VA PRV and degree of SA stenosis has not been examined.…”

Postendovascular thoracic aortic repair subclavian steal syndrome revealed by severe headache

“…The term ''subclavian steal syndrome'' should only be used in cases where this aberrant blood flow causes symptoms, because completely reversed flow in the VA does not always indicate SCSS [7]. In general, symptoms can be separated as ischemia of the left upper extremity and/or posterior cerebral circulation and spinal cord.…”

Clinical significance of reversal of flow in the vertebral artery identified on cerebrovascular duplex ultrasound

“…5 Duplex ultrasound is a commonly used and costeffective imaging modality for evaluating carotid and vertebral arterial circulation. 6,7 Studies suggest that many patients with ultrasound evidence of reversal of flow in the vertebral artery (RFVA) are asymptomatic at the time of diagnosis. 2,6,8 In symptomatic patients, percutaneous transluminal angioplasty and stenting of the SCA, carotid-subclavian bypass, and subclaviancarotid artery transposition have proved effective in eliminating or reducing symptoms of SSS.…”