Detection of reverse flow by duplex ultrasonography in orthostatic hypotension.
OBJECTIVE
The aim of this study is to elucidate the effect of orthostatic hypotension on changes in cerebral blood flow.


METHODS
Blood flow velocities of both the common carotid artery and vertebral artery were measured using duplex ultrasonography in 12 patients: 6 with familial amyloidotic polyneuropathy, 3 with Shy-Drager syndrome, 2 with pandysautonomia, and 1 with senile orthostatic hypotension. Simultaneously, peripheral blood flow was also evaluated by laser-Doppler flowmetry.


RESULTS
The patients showing dizziness or syncope when tilted to a 70 degrees upright position exhibited characteristic reverse flow at the end-diastolic phase on the Doppler flow image of both the common carotid and vertebral arteries, which was effectively treated by infusion of 2.5 micrograms/min norepinephrine for 10 minutes. This end-diastolic reverse flow was not seen in any patients who did not have dizziness or syncope. After subjects were tilted from a supine to a 70 degrees upright position, decrease in the peripheral blood flow of the patients with orthostatic hypotension remained unchanged for at least 5 minutes, whereas that of control subjects was recovered within 2 minutes. However, no significant difference between the patients with and without clinical symptoms was observed.


CONCLUSIONS
These results suggest that detection of this specific echographic pattern may be quantitatively useful in examination of clinical symptoms accompanying orthostatic hypotension and that duplex ultrasonography may be a helpful tool to evaluate the effect of drugs used for controlling these clinical signs.
First Department of Internal Medicine, Kumamoto University School of Medicine, Japan.
T
T
Yonehara
Y
Y
Ando
K
K
Kimura
M
M
Uchino
M
M
Ando
D000328:Adult; D000368:Aged; D017772:Amyloid Neuropathies / Q000000981:diagnostic imaging / Q000503:physiopathology; D001342:Autonomic Nervous System Diseases / Q000000981:diagnostic imaging / Q000503:physiopathology; D001775:Blood Circulation / Q000502:physiology; D001783:Blood Flow Velocity / Q000502:physiology; D017536:Carotid Artery, Common / Q000503:physiopathology; D016022:Case-Control Studies; D002560:Cerebrovascular Circulation / Q000502:physiology*; D004244:Dizziness / Q000188:drug therapy / Q000503:physiopathology; D005260:Female; D006801:Humans; D007024:Hypotension, Orthostatic / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D017078:Laser-Doppler Flowmetry; D008297:Male; D008875:Middle Aged; D009638:Norepinephrine / Q000627:therapeutic use; D011187:Posture / Q000502:physiology; D012791:Shy-Drager Syndrome / Q000000981:diagnostic imaging / Q000503:physiopathology; D016683:Supine Position / Q000502:physiology; D013575:Syncope / Q000188:drug therapy / Q000503:physiopathology; D013997:Time Factors; D018608:Ultrasonography, Doppler; D014711:Vertebral Artery / Q000503:physiopathology
D009638:Norepinephrine