Presenting symptoms significantly predict outcome after carotid endarterectomy. This should be considered both in patient selection and comparison of patient series.

There was an association between echolucent type I and II carotid plaques and the presence of symptoms but not their type. Plaque morphology was not characteristic in a subgroup of patients who had stroke without warning. Further prospective study of plaque morphology in asymptomatic patients might help identify high-risk groups.

After carotid endarterectomy restenosis is rarely associated with symptoms; contralateral stroke is rare and is not associated with progressive internal carotid artery disease suitable for endarterectomy. This study has shown no benefit from long-term duplex surveillance after carotid endarterectomy. Selective clinical follow-up of patients who have high-grade contralateral stenoses would appear more appropriate.

This study suggests that patch angioplasty of larger carotid arteries may be unnecessary. Randomisation of larger arteries between patch and primary closure would be required to confirm this.

Duplex scanning within a week of carotid endarterectomy identifies > 50% residual stenosis, in addition to minor residual 25% to 50% stenosis and small carotid dimensions, which are good predictors of > 50% restenosis at 6 months.