Clinical and Imaging Features Associated with an Increased Risk of Early and Late Stroke in Patients with Symptomatic Carotid Disease

ObjectiveThe aim of this review was to identify clinical and/or imaging parameters that are associated with an increased (decreased) risk of early/late stroke in patients with symptomatic carotid disease.In the first 14 daysNatural history studies suggest that 8–15% of patients with 50–99% stenoses will suffer a stroke within 72 hours of their index symptom. Currently, there are insufficient validated data to identify highest-risk patients for emergency carotid endarterectomy (CEA), but an increased risk of stroke appears to be predicted by (i) an ABCD2 score of 4–7; (ii) the presence of acute cerebral injury on CT/MRI; (iii) Gray Scale Median (GSM) <15, (iv) spontaneous embolisation on Transcranial Doppler (TCD); and (v) increased fluorodeoxyglucose (FDG) uptake in the carotid plaque on positron emission tomography (PET). A future goal must be to develop predictive algorithms (based on accessible imaging strategies) for identifying acutely symptomatic patients with highly unstable plaques for emergency CEA.Medium to long termIn the randomised trials, about 70% of patients with symptomatic 70–99% stenoses were stroke-free on “best medical therapy” at 5 years. Clinical predictors of increased stroke risk include (i) male gender; (ii) age >75; (iii) hemispheric symptoms; and (iv) increasing comorbidity. Imaging features associated with increased stroke risk include (i) irregular stenoses; (ii) contralateral occlusion; (iii) increasing stenosis severity, but not subocclusion; (iv) tandem intracranial disease; (v) a failure to recruit intracranial collaterals; (vi) low GSM; (vii) MR diagnosis of intra-plaque haemorrhage; (vii) spontaneous embolisation on TCD; and (viii) increased FDG uptake in the carotid plaque on PET. Clinical/imaging parameters associated with a lower risk of stroke include (i) female gender, especially those with 50–99% stenoses; (ii) ocular symptoms/lacunar stroke; (iii) smooth stenoses; and (iv) chronic subocclusion.