Comparison of mid-term outcomes of carotid artery stenting for moderate versus critical stenosis

INTRODUCTION Little is known about the prognosis of moderate versus critical carotid stenosis treated by carotid artery stenting (CAS). MATERIAL AND METHODS This was a retrospective analysis of a single-centre registry including 271 consecutive patients (69 ±9 years, 87% at high risk for surgery), in whom 308 procedures were performed. The study included both symptomatic (≥ 50% carotid artery stenosis) and asymptomatic (≥ 70% carotid artery stenosis) patients. The primary endpoint was the rate of adverse events during follow-up (range 1-48 months), defined as all-cause death or stroke. RESULTS We treated 115 critical and 193 moderate stenoses and implanted 318 stents (56% with closed cell design). Embolic protection systems were used in 296 cases (96%). The technical success rate was 98.2% in the critical stenoses group and 99% in the moderate group (NS). During follow-up, the incidence of the primary endpoint was 12.9% (13 pts) in the critical stenoses group and 14.7% (25 pts) in the moderate stenoses group (estimated 3-year freedom from death/stroke was 0.844 vs. 0.812; log-rank test p = 0.983). Left ventricular ejection fraction < 40%, significant contralateral carotid artery occlusion or stenosis and renal insufficiency were identified as significant predictors of the primary endpoint (p < 0.03). CONCLUSIONS Carotid artery stenting with embolic protection systems in patients at high risk for carotid endarterectomy is safe. Patients with initially moderate and critical stenoses have an identical mid-term prognosis with regard to death and stroke.