Hypoplasia, stenosis and other alterations of the vertebral artery: does impaired blood rheology manifest a hidden disease?
OBJECTIVE
The clinical relevance of abnormal vessel findings in the posterior circulation is still a matter of controversy.


METHODS
We compared 48 patients displaying sonographic abnormalities of one vertebral artery, i.e., vertebral artery hypoplasia in 24 cases, stenosis in 13 cases, plaques in 11 cases, with 25 healthy subjects in terms of whole blood viscoelasticity and plasma viscosity.


RESULTS
All patients with stenosis and plaques suffered from clinical signs and symptoms of ischemic cerebrovascular disease, predominantly in the posterior circulation. Free of acute clinical symptoms were 5 of the 24 patients with hypoplasia. Highly statistically significant differences in blood viscoelasticity were found between the patients and the healthy subjects. As regards differences between the groups, whole blood viscoelasticity was most impaired in stenosis, shear resistance was significantly higher in stenosis compared to hypoplasia. Symptom-free patients with one-sided vertebral artery hypoplasia had a significantly better, nearly normal blood rheology at a low shear rate (10/s), compared to clinically symptomatic patients with hypoplasia.


CONCLUSIONS
The results of the present study offer some evidence that altered hemorheology may be associated with symptomatic vertebrobasilar occlusive disease.
University Clinic of Neurology, University of Vienna, Austria.
B
B
Oder
W
W
Oder
W
W
Lang
E
E
Marschnigg
L
L
Deecke
D001157:Arterial Occlusive Diseases / Q000150:complications / Q000000981:diagnostic imaging / Q000473:pathology*; D001488:Basilar Artery / Q000000981:diagnostic imaging / Q000473:pathology; D001809:Blood Viscosity / Q000502:physiology; D001921:Brain / Q000098:blood supply*; D002545:Brain Ischemia / Q000000981:diagnostic imaging / Q000209:etiology / Q000473:pathology; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009460:Neurologic Examination; D012189:Retrospective Studies; D012212:Rheology; D014463:Ultrasonography; D014711:Vertebral Artery / Q000000981:diagnostic imaging / Q000473:pathology*