Effect of subclavian syndrome on the basilar artery.
Fifty-five patients with a permanent or intermittent subclavian steal syndrome demonstrated by continuous wave Doppler were included in a prospective study: 25 patients without vertebro-basilar symptoms, 8 symptomatic patients with defined vertebro-basilar symptoms and 22 with hemodynamic vertebro-basilar occurrences. The basilar artery velocity was recorded by Transcranial Doppler Sonography in baseline conditions, and after a hyperaemia test to the upper limb. A spontaneous, incomplete basilar steal was diagnosed in seven patients, and a complete basilar steal in one patient, (14.5% of the cases). After hyperaemia test, 18 other incomplete basilar steal were observed. The occurrence of a basilar steal was higher in the vertebro-basilar group (57% of the cases) especially in 7 of the 8 cases with defined vertebro-basilar symptoms; it was lower in the patients without vertebro-basilar occurrences (36% of the cases). This basilar steal was also seen in five of the six symptomatic patients with opposite vertebral artery stenosis above a 50% diameter. Transcranial Doppler Sonography could help to define a subgroup of subclavian steal syndrome with a high risk of strokes.
Department of Neurology (A and B), University Hospital, Angers, France.
J M
JM
de Bray
J P
JP
Zenglein
J P
JP
Laroche
P A
PA
Joseph
P
P
Lhoste
J
J
Pillet
F
F
Dubas
J
J
Emile
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001488:Basilar Artery / Q000000981:diagnostic imaging; D001783:Blood Flow Velocity / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013349:Subclavian Steal Syndrome / Q000000981:diagnostic imaging*; D017585:Ultrasonography, Doppler, Transcranial; D014715:Vertebrobasilar Insufficiency / Q000000981:diagnostic imaging*