Preoperative cerebral hemodynamics and shunting during carotid endarterectomy in patients with severe unilateral carotid stenosis.
OBJECTIVE
To estimate the possible predictors for the need for shunting during carotid endarterectomy in patients with severe unilateral carotid stenosis based on preoperative transcranial Doppler sonographic examination.


METHODS
One hundred twenty-six patients were included in the study. Pulsatility index, flow acceleration, peak systolic velocity, and mean velocity were measured in the middle cerebral artery (MCA) and anterior cerebral artery on both sides. Cerebrovascular reactivity (CVR) was evaluated in 21 patients with shunts and in 55 patients without shunts.


RESULTS
The shunted and nonshunted groups did not differ with regard to demographic and clinical characteristics. The side-to-side difference in peak systolic velocity and mean velocity of the MCA was significantly higher in patients with shunts. CVR were significantly higher in the patients without shunts (36.0 +/- 17.2%) than in patients with shunts (16.6 +/- 11.4%; p = 0.0003). The peak systolic velocity and mean velocity asymmetry of the MCA had relatively low receiver operating characteristics, whereas CVR exhibited a relatively high accuracy in predicting the need for shunting.


CONCLUSIONS
Low CVR and increased asymmetry of MCA velocities were found in patients who subsequently required shunting during carotid endarterectomy. The relatively low accuracy of the MCA asymmetry should prevent the use of this criterion as a reliable preoperative predictor for shunting during carotid surgery, whereas CVR was more accurate and may prove useful in this setting.
Telman
Gregory
G
Department of Neurology, Rambam Medical Center and Technion Faculty of Medicine, Haalija Street 8, Haifa 32801, Israel.
Kouperberg
Efim
E
Nitecki
Sami
S
Karram
Toni
T
Schwarz
Henry A
HA
Sprecher
Elliot
E
Hoffman
Aaron
A
Yarnitsky
David
D
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000714:Anastomosis, Surgical; D020771:Anterior Cerebral Artery / Q000000981:diagnostic imaging; D050197:Atherosclerosis / Q000601:surgery; D001783:Blood Flow Velocity / Q000502:physiology; D002339:Carotid Arteries / Q000601:surgery; D016893:Carotid Stenosis / Q000601:surgery*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D016894:Endarterectomy, Carotid; D005260:Female; D005544:Forecasting; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D020768:Middle Cerebral Artery / Q000000981:diagnostic imaging; D011183:Postoperative Complications; D011300:Preoperative Care; D011673:Pulsatile Flow / Q000502:physiology; D020521:Stroke / Q000209:etiology; D017585:Ultrasonography, Doppler, Transcranial