Postoperative occlusion after carotid endarterectomy.

Noninvasive testing (Doppler imaging and spectral analysis of carotid flow) was performed in 70 symptomatic patients who required unilateral carotid endarterectomy. Angiographic correlations were made with the noninvasive tests before surgery, and postoperatively hemodynamic changes were determined during a three-year follow-up period. Postoperative stenosis occurred in 9% (3% early and 6% late) of the patients. Clinical progression on the unoperated side (new symptoms or bruits) occurred in 15 patients. Ten of these 15 patients had significant hemodynamic progression of disease in the unoperated carotid as well. Clinically occult hemodynamic progression of disease on the unoperated side was detected by noninvasive testing in four of the cases. Neurological complications resulting from postoperative occlusion occurred in two cases.