The role of external carotid endarterectomy in the treatment of ipsilateral internal carotid occlusion: collective review

Abstract

Complete occlusion of the internal carotid artery (ICA) may result in a variety of clinical states. Neurologic symptoms in the setting of ICA occlusion may be due to embolic events through the external carotid artery (ECA) circulation, hemodynamic insufficiency resulting from inadequate collateral development, or propagation of clot intracranially. External carotid reconstruction has been used to prevent neurologic events from the first two mechanisms. This review attempts to place in perspective the current indications for, techniques of, and results from ECA revascularization. A discussion of the cerebral collateral circulation is included for reference. Twenty-three series were collected from the literature. Cases were excluded in which procedures other than ECA reconstruction were undertaken, leaving 218 cases for analysis. These represented 195 EC endarterectomies and 23 ECA bypasses. Resolution of symptoms was seen in 83% of patients with another 7% showing marked improvement. The perioperative mortality rate was 3%; neurologic deaths accounted for most perioperative deaths. The overall neurologic complication rate was 5%. More recent reports were notable for improved mortality and morbidity. A diseased contralateral carotid artery was associated with higher neurologic morbidity whereas disease in the vertebral arteries had no impact on outcome. The best results were obtained when surgery was performed to relieve specific hemispheric or retinal symptoms as opposed to nonspecific neurologic complaints or previous stroke. The symptomatic patient with ICA occlusion has a poor neurologic prognosis. In selected circumstances ECA reconstruction should be considered among the treatment options in this clinical setting.