The natural history of the external carotid artery after carotid endarterectomy: Implications for management

Purpose: Most surgeons perform some type of endarterectomy of the external carotid artery (EGA) routinely during standard carotid endarterectomy (CEA). This approach has been shown to result in a small percentage of ECA occlusions, the clinical significance of which remains poorly understood. We have modified our approach to the management of the ECA during standard CEA by averting any attempt at external CEA. To evaluate the natural history of the untreated ECA after CEA, we reviewed the preoperative, postoperative, and follow-up duplex scans obtained from 232 CEAs over the past 4 years. Methods: Preoperative and postoperative carotid artery duplex examinations with specific evaluation of the extent of ECA stenosis were available for review on 114 CEAs performed between January 1991 and July 1994. All CEAs were performed for internal carotid artery stenosis greater than 75% as determined by duplex scanning, which was confirmed by either contrast arteriography or magnetic resonance angiography. Results: Seventy-three (64.0%) procedures were performed for symptomatic lesions, whereas 41 (36.0%) were performed for asymptomatic stenosis. There were no perioperative strokes or transient ischemic attacks in this group, and there was one postoperative death (0.9%). Short- and intermediate-term follow-up demonstrated insignificant changes in ECA diameter after operation, with no cases of ECA occlusion and only five cases progressing to greater than 75% on the 1-year follow up duplex examination. Conclusion: We conclude from these data that averting external CEA during standard CEA does not result in significant progression of ECA stenosis or occlusion.