Correlation of intra-operative duplex findings during carotid endarterectomy with neurological events and recurrent stenosis at one year.

OBJECTIVES: Carotid endarterectomy has been used to treat both asymptomatic and symptomatic disease and this has meant that recurrent stenosis and its effect on late stroke risk have become increasingly important. In this study we compared anatomical defects and residual stenosis identified intra-operatively with recurrent stenosis and new symptoms developing in the first year after surgery. DESIGN, MATERIALS & METHODS: Two hundred and forty-four consecutive patients undergoing carotid endarterectomy were studied prospectively. Residual anatomical defects were noted; residual stenosis was defined by intra-operative duplex ultrasound as >50%. New stenoses and clinical events during the one-year surveillance period were documented. RESULTS: There was an increased incidence of recurrent stenosis at one year in vessels with residual stenoses (p<0.001) and in vessels containing a residual anatomical defect (p=0.037). There was no significant difference in recurrent stenosis rate with respect to closure (primary or patch) or seniority of surgeon but recurrent stenosis was increased in females (p=0.026). The majority (70%) of restenotic lesions were localised to the origin of the internal carotid artery. The late stroke rate was 0.9% and was not related to recurrent stenosis or symptoms.CONCLUSIONS: Residual stenosis and intra-luminal defects at completion increase the recurrent stenosis rate at one year. The aetiology of recurrent stenosis is multi-factorial and further studies are required to determine whether it is justified to modify the criteria for re-exploration with a view to reducing recurrent stenosis.