Long term functional equivalence of carotid endarterectomy and stenting for symptomatic stenosis.
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.