The International Carotid Stenting Study (ICSS) was the largest of the trials assessed that compared carotid artery stenting with carotid endarterectomy in patients with symptomatic carotid artery stenosis, and reported an interim safety analysis of outcomes within 120 days of randomisation in 2010 1).
The ICSS primary analysis shows that stenting is as effective as endarterectomy in preventing fatal or disabling stroke in patients with symptomatic carotid stenosis up to 10 years after treatment. Carotid stenting was associated with a higher procedure-related and long-term risk of non-disabling stroke than endart- erectomy, but functional ability did not differ overall. Both treatments seemed to be equally preventive against ipsilateral stroke and severe restenosis of the treated carotid artery.
The ICSS trial randomized 1710 patients across 50 centers with symptomatic carotid artery disease to stenting versus endarterectomy. Given the 10-year study horizon, substantial variability in stenting procedural strategy and devices occurred. The intention-to-treat analysis was high fidelity. Only 9 and 15 patients crossed over to endarterectomy and stenting respectively; 16 stent patients and 21 endarterectomy patients never received the procedure.
Overall, both treatments provided durable patency of the target vessel and comparable frequency of fatal or disabling strokes (52 versus 49 events). CEA and CAS were equivalent at this 5-year primary end point.
Though minor stroke events (119 versus 72: 5 year HR 1.75 with p value < 0.001) were higher in the stenting group, functional outcome by mRS were identical. Minor stroke events with stenting commonly involved other territories and may be attributable to aortic arch access. Two enrolling sites were further stopped from further stent enrollment due to outlier interventional complication rates; these complications were included in the final trial results.
Outcomes of carotid endarterectomy (CEA) or carotid angioplasty and stenting (CAS) for asymptomatic disease in patients on dialysis are not well characterized, with questionable stroke prevention and survival. Patients on dialysis have high perioperative and long-term stroke or death rates after CEA or CAS for asymptomatic stenosis, with a median survival that is less than recommended by current guidelines. As a result, carotid intervention in these patients appears to be inappropriate 3).