Hyperintense carotid plaque on T(1)-weighted turbo-field echo MRI in symptomatic patients with low-grade carotid stenosis and carotid occlusion

BACKGROUND

In addition to stenosis grading, magnetic resonance imaging (MRI) may provide valuable information about plaque 'status', e.g. hyperintense vulnerable carotid plaque, associated with higher morbidity and mortality. In the present study, we investigated the prevalence, clinical and radiological correlates of hyperintense carotid plaques on T(1)-weighted turbo-field echo (T(1)w-TFE) MRI in patients with ischemic symptoms.

METHODS

A total of 153 patients presenting with transient ischemic attack or ischemic infarct, studied with contrast-enhanced magnetic resonance angiography (CEMRA), were retrospectively examined. Stenosis grade was obtained from CEMRA images, presence or absence of hyperintense carotid plaque from T(1)w-TFE MRI. Stenosis grade and baseline characteristics were compared between patients with and without a hyperintense plaque.

RESULTS

Twenty-eight patients (18%) showed one or more hyperintense internal carotid (ICA) plaques. Hyperintense plaques were found in patients with <50% stenosis (6 of 158 ICAs), 50-70% stenosis (4 of 11), >70% stenosis (14 of 74) and carotid occlusion (4 of 28). Presence of hyperintense plaque was associated with older age (70 vs. 62 years; p < 0.05), higher prevalence of cardiac disease (61 vs. 28%; p < 0.01), ischemic infarct as presenting symptom (37 vs. 14%; p < 0.01), ischemic cerebral lesions on MRI (63 vs. 32%; p < 0.01), and the ICA on the patients' symptomatic side (70 vs. 42%; p < 0.01).

CONCLUSIONS

More than one third of patients with 50-70% stenosis present with a hyperintense plaque. This subgroup of patients could in the future possibly benefit from more aggressive medicinal therapy or revascularization.

Mechanisms of gender-related outcome differences after carotid endarterectomy

OBJECTIVE

Large randomized trials have confirmed a difference in outcome after carotid endarterectomy (CEA) between men and women. In this review, we aimed to provide an overview of the gender-specific characteristics causing these perioperative and long-term outcome differences between men and women after CEA.

METHODS

A systematic search strategy with the synonyms of 'gender' and 'carotid endarterectomy' was conducted from PubMed and EMBASE databases. Only 11 relevant studies specifically discussing gender-specific related characteristics and their influence on outcome after CEA could be identified.

RESULTS

Due to the limited number of included studies, pooling of findings was impossible, and results are presented in a descriptive manner. Each included study described only one possible gender-specific factor. Differences in carotid artery diameter, sex hormones, sensitivity for antiplatelet therapy, plaque morphology, occurrence of microembolic signals, and restenosis rate have all been suggested as gender-specific characteristics influencing outcome after CEA.

CONCLUSION

Higher embolic potential in women and relatively stable female plaque morphology are the best-described factors influencing the difference in outcomes between men and women. However, the overall evidence for outcome differences by gender-specific characteristics in the literature is limited.

Carotid artery stenting compared with endarterectomy in patients with symptomatic carotid stenosis (International Carotid Stenting Study): an interim analysis of a randomised controlled trial

BACKGROUND

Stents are an alternative treatment to carotid endarterectomy for symptomatic carotid stenosis, but previous trials have not established equivalent safety and efficacy. We compared the safety of carotid artery stenting with that of carotid endarterectomy.

METHODS

The International Carotid Stenting Study (ICSS) is a multicentre, international, randomised controlled trial with blinded adjudication of outcomes. Patients with recently symptomatic carotid artery stenosis were randomly assigned in a 1:1 ratio to receive carotid artery stenting or carotid endarterectomy. Randomisation was by telephone call or fax to a central computerised service and was stratified by centre with minimisation for sex, age, contralateral occlusion, and side of the randomised artery. Patients and investigators were not masked to treatment assignment. Patients were followed up by independent clinicians not directly involved in delivering the randomised treatment. The primary outcome measure of the trial is the 3-year rate of fatal or disabling stroke in any territory, which has not been analysed yet. The main outcome measure for the interim safety analysis was the 120-day rate of stroke, death, or procedural myocardial infarction. Analysis was by intention to treat (ITT). This study is registered, number ISRCTN25337470.

FINDINGS

The trial enrolled 1713 patients (stenting group, n=855; endarterectomy group, n=858). Two patients in the stenting group and one in the endarterectomy group withdrew immediately after randomisation, and were not included in the ITT analysis. Between randomisation and 120 days, there were 34 (Kaplan-Meier estimate 4.0%) events of disabling stroke or death in the stenting group compared with 27 (3.2%) events in the endarterectomy group (hazard ratio [HR] 1.28, 95% CI 0.77-2.11). The incidence of stroke, death, or procedural myocardial infarction was 8.5% in the stenting group compared with 5.2% in the endarterectomy group (72 vs 44 events; HR 1.69, 1.16-2.45, p=0.006). Risks of any stroke (65 vs 35 events; HR 1.92, 1.27-2.89) and all-cause death (19 vs seven events; HR 2.76, 1.16-6.56) were higher in the stenting group than in the endarterectomy group. Three procedural myocardial infarctions were recorded in the stenting group, all of which were fatal, compared with four, all non-fatal, in the endarterectomy group. There was one event of cranial nerve palsy in the stenting group compared with 45 in the endarterectomy group. There were also fewer haematomas of any severity in the stenting group than in the endarterectomy group (31 vs 50 events; p=0.0197).

INTERPRETATION

Completion of long-term follow-up is needed to establish the efficacy of carotid artery stenting compared with endarterectomy. In the meantime, carotid endarterectomy should remain the treatment of choice for patients suitable for surgery.

FUNDING

Medical Research Council, the Stroke Association, Sanofi-Synthélabo, European Union.