The subclavian steal phenomenon: a common vascular disorder with rare neurologic deficits.
Three hundred twenty-four patients with reversed vertebral artery blood flow were reviewed for cerebrovascular events. Neither the presence nor the type of vertebral artery steal (permanent, n = 204; intermediate, n = 120) determined neurologic symptoms, which rather were related to coincidental carotid obstructions or abnormal flow velocity patterns in the basilar artery. Most patients (n = 209; 64%) had no neurologic symptoms. Hemispheric events (n = 99; 31%) occurred most frequently in patients with additional carotid lesions and nonhemispheric events in a few patients (n = 16; 5%) often with bilateral vertebral steal. Intracranial Doppler studies from the vertebral and basilar arteries excluded spontaneous retrograde basilar artery perfusion in any of a subgroup of 50 patients examined in addition. Thus, blood flow reversal in extracranial arteries is a marker for atherosclerotic vascular disease in general, rather than an indicator of a patient's risk to develop cerebrovascular events from hemodynamic insufficiency in the territory affected. Surgical treatment is discouraged for most patients with this benign flow abnormality.
Hennerici
M
M
Department of Neurology, University of Düsseldorf, West Germany.
Klemm
C
C
Rautenberg
W
W
D000368:Aged; D001488:Basilar Artery / Q000503:physiopathology; D001783:Blood Flow Velocity; D002545:Brain Ischemia / Q000209:etiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D002546:Ischemic Attack, Transient / Q000209:etiology; D008297:Male; D009422:Nervous System Diseases / Q000209:etiology*; D012039:Regional Blood Flow; D013349:Subclavian Steal Syndrome / Q000150:complications* / Q000503:physiopathology; D014711:Vertebral Artery / Q000503:physiopathology