title: Regional cerebral blood flow and vertebral angiography at rest and in connection with arm work in patients with the "subclavian steal phenomenon".
abstract: Vascular anatomy and haemodynamics of the vertebro-basilar system were investigated by means of vertebral angiography as well as rCBF measurements using the 133Xenon clearance method in 12 patients with occlusive disease of the subclavian artery. Prior to the investigation, the occlusive lesions had been demonstrated by aortocervical angiography, which in 9 out of 12 patients showed reversed vertebral blood flow at rest. All selective vertebral angiographies and rCBF measurements were performed at rest and in connection with graded arm exercise. Patients with the subclavian steal phenomenon were found to have a slightly reduced rCBF. After arm exercise, the intracranial flow velocity of contrast medium in the cerebral vessels remained unchanged, while the velocity of the reversed flow of contrast medium in the vertebral artery was increased. Regional cerebral blood flow in the vertebro-basilar system increased during arm exercise, the average increase being about 16%. The augmentation of flow is probably due to activation of neuronal processes within the brain. The magnitude of these flow alterations in healthy individuals is unknown.
mesh_terms: D000328:Adult; D000368:Aged; D001783:Blood Flow Velocity; D001794:Blood Pressure; D002533:Cerebral Angiography; D002560:Cerebrovascular Circulation; D003097:Collateral Circulation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D005082:Physical Exertion; D013349:Subclavian Steal Syndrome / Q000000981:diagnostic imaging / Q000503:physiopathology*; D014711:Vertebral Artery / Q000000981:diagnostic imaging*