Managing carotid stenosis as secondary prevention of stroke or transient ischaemic attack

All patients with ischaemic stroke or TIA in the territory of the carotid circulation should be screened promptly for a carotid stenosis, which is presumed to be the source of atheroembolism. If the only stenosis seen is in the vessel supplying the unaffected hemisphere (asymptomatic carotid stenosis), see advice—management is different.

If a carotid stenosis in the vessel supplying the affected hemisphere is found on ultrasound, confirm this with a second, independent imaging test (eg computed tomography angiography, magnetic resonance angiography, digital subtraction angiography) if possible.

If the patient with recent mild stroke or TIA has a high-grade ipsilateral carotid stenosis (more than or equal to 70%), refer for urgent carotid endarterectomy. The benefit of surgery is greatest within 2 weeks of a TIA or mild stroke, as this is when the risk of recurrent stroke is greatest. Benefit is marginal for patients with 50 to 69% symptomatic stenosis or when surgery is delayed beyond 3 months.

Percutaneous transluminal cerebrovascular angioplasty and stenting is less effective than carotid endarterectomy. It may be considered in certain circumstances, usually when technical challenges increase the risk of surgery (eg previous neck radiotherapy, high carotid bifurcation, medical comorbidities).

After endarterectomy, all patients need intensive secondary prevention therapy (ie an antiplatelet drug, blood pressure lowering, cholesterol lowering, lifestyle measures [including stopping smoking]).