Carotid Artery Stenting Versus Carotid Endarterectomy for Treatment of Asymptomatic Carotid Artery Stenosis

Asymptomatic carotid stenosis is common and is associated with increased risk of stroke. The relative efficacy and safety of carotid endarterectomy (CEA) and carotid stenting (CAS) in patients with asymptomatic carotid stenosis remain unclear. Five studies that recruited patients with asymptomatic but significant carotid stenosis, who underwent CEA or CAS, were included in this systematic review and meta-analysis. The analyzed outcomes included risks of stroke, myocardial infarction (MI), and death. Risk ratio (RR) and 95% confidence interval (95% CI) were calculated and pooled for meta-analysis. Pooled analysis demonstrated that compared with CEA, CAS was associated with a decreased risk of MI (RR = 0.49, 95%CI = 0.26-0.91, P = 0.023) and slightly increased risk of stroke, although not significant (RR = 1.69, 95% CI = 0.97-2.92, P = 0.063). There was no difference in the death rates between the groups (RR = 0.60, 95% CI = 0.17-2.18, P = 0.436). In the subgroup analysis, CAS was associated with a decreased risk of MI in mixed patients (RR = 0.45, 95% CI = 0.26-0.78, P = 0.005), but not in asymptomatic patients (RR = 0.549, 95% CI = 0.26-1.17, P = 0.119). Compared with CAS, CEA was associated with decreased risk of perioperative stroke and increased risk of MI; it did not affect the risk of death in patients with asymptomatic carotid stenosis. In the subgroup analysis, the decreased risk of MI after CAS was significant only in the mixed patients group. CAS was associated with higher risk of stroke but lower risk of MI than those with CEA. Both procedures appeared equivalent in terms of the risk of death.