Influence of the contralateral carotid artery on neurologic complications following carotid endarterectomy.

To examine the effect of contralateral carotid artery stenosis on postoperative events, a retrospective review was made of 451 patients undergoing 510 carotid endarterectomies during a 6-year period. Three degrees of contralateral carotid stenosis were identified radiologically: 0% to 49%, 50% to 99%, and totally occluded. Each group was further separated into two categories according to preoperative symptoms. "Low risk" included asymptomatic lesions, transient ischemic attacks, and nonhemispheric symptoms; "high risk" described poststroke patients and urgent operations. The results show the incidence of stroke or death was not increased in patients with severely stenosed or occluded contralateral vessels in either low- or high-risk patients (p = 0.741 and p = 0.561, respectively). Patients in the high-risk category, however, had a significantly higher risk of postoperative complications than patients in the low-risk category (p less than 0.001). The study reaffirms that preoperative indications have a major influence on surgical outcome and suggests that the status of the contralateral artery has little bearing on postoperative events.