Oxidative injury associated with stenting of asymptomatic carotid artery stenosis

Abstract

1.16 % and 0.74 %, respectively, while after carotid stenting CHS and ICH occurred in 1.9 % and 0.37 % of patients correspondingly [4] The study by Saraçoğlu E. et al. showed a positive correlation between CHS and oxidative stress biomarkers emphasizing that measurement of oxidative stress perioperatively might play a role in the diagnosis and treatment of the hyperperfusion syndrome.High grade ipsilateral carotid stenosis with poor collateral fl ow, contralateral carotid occlusion, incomplete circle of Willis, attenuated cerebrovascular reactivity after acetazolamide, and postoperative hypertension are risk factors for the development of CHS [5]. Based on the results of the study, an antioxidant therapy should be considered in subgroups of patients with increased risk of developing CHS after CAS.Current guidelines recommend revascularization in most patients with severe asymptomatic carotid artery stenosis. These guidelines are based on older studies that do not refl ect the changing natural history of asymptomatic carotid artery stenosis infl uenced with best medical therapy. Optimal medical management of patients with asymptomatic carotid stenosis has improved signifi cantly over the past 20 years, with stroke rates having declined markedly. The second important issue that has been raised by this study is the rate of occurrence of embolic infarcts in MRI images after CAS. It is well documented that carotid angioplasty and stent placement carry a considerable risk of distal cerebral embolization, precipitating new brain ischaemic lesions and neurologic symptoms. New lesions seen on postintervention MRI images vary between 17 % and 63 % and are not detected at neurologic examination [5,6]. In a recent study by Bijuklic et al. postprocedure new cerebral ischaemic lesions were detected in 32.8 % of patients [7]. The prognostic impact of silent CAS-related brain embolization is still a matter of debate in the absence of neurological symptoms. A recent study showed that microembolization after CAS may persist at six months after the intervention, emphasizing the need for further investi-