Modalities of surveillance after carotid endarterectomy: impact of surgical technique.

The purpose of this study was to assess the need for follow-up duplex scan (DS) 1 year after carotid endarterectomy (CE) performed with prosthetic patching and intraoperative completion arteriography. Between April 1994 and December 2000, a total of 605 CE procedures with prosthetic patch closure and intraoperative completion arteriography were performed in 540 patients. All patients underwent DS at 4 days and then yearly after the procedure. Five patients died during the early postoperative course and eight suffered a nonfatal stroke (combined neurological morbidity-mortality rate, 2.4%). Intraoperative completion arteriography showed abnormalities in 114 cases, including 17 involving the internal carotid artery (ICA) and 73 involving the external carotid artery (ECA). Successful revision was achieved in all cases and confirmed by repeat arteriography. Postoperative DS at 4 days detected three abnormalities involving the ICA (0.5%), including asymptomatic occlusion in one case and residual stenosis >50% in two cases. Ninety-eight percent of patients were stenosis-free at 1 year. Actuarial stroke-free survival was 98.3% at 3 years. Diameter reduction of the contralateral carotid artery progressed over 70% within 1 year after CE in 22.9% of patients with contralateral carotid stenosis over 50% at the time of the initial intervention. The findings of this study indicate that DS follow-up 1 year after CE with intraoperative completion arteriography is unnecessary unless postoperative DS demonstrates residual stenosis of the ICA. However, DS at 1 year is beneficial for patients presenting with contralateral carotid artery disease with diameter reduction >50% at the time of CE.