Effects of Age and Symptom Status on Silent Ischemic Lesions after Carotid Stenting With and Without the Use of Distal Filter Devices

Abstract

Conclusion: Distal filter devices can reduce the incidence of new diffusion-weighted imaging (DWI) lesions associated with carotid stenting, but benefit may not necessarily pertain to older and asymptomatic patients. Summary: Routine use of distal filter devices during carotid angioplasty and stenting (CAS) remains controversial. The authors sought to determine if certain subgroups of patients might benefit compared with others with the use of filter devices. They used new lesions shown on DWI as surrogate markers for stroke. Sixty patients underwent CAS with a distal filtration device and 175 without a distal protective device. All patients were studied with DWI imaging immediately before and after CAS. Patients were stratified according to age and symptom status. New ipsilateral DWI lesions were frequent after CAS in patients with and without neural protective devices; however, there appeared to be fewer lesions in patients undergoing protected (52%) vs unprotected CAS (68%). In symptomatic patients, there was a 56% prevalence of new DWI lesions with protective devices vs 74% in those without the use of protective devices. In patients aged <75 years, incidence of DWI lesions was 46% with protective devices vs 67% without protective devices (all P < .05). In asymptomatic patients and in patients aged >75 years, the proportion of patients with new lesions and the total number of new lesions were not significantly different between those treated with protected and unprotected CAS. For the entire study population, the incidence of any stroke or death '30 days was not significantly different between patients treated with and without neural protection (8.8% vs 5.1%; P = .4). Neurologic complication rates ≤30 days also were not significantly different among younger, older, symptomatic, or asymptomatic patients treated with and without protective devices. Comment: This is a retrospective and nonrandomized study. The nature of the study design does not truly permit conclusions about the utility of neuroprotective devices in symptomatic vs asymptomatic and younger vs older patients. Nevertheless, the high prevalence of new DWI lesions in patients treated with and without neuroprotective devices and the lack of dramatic effects of neuroprotective devices on neurologic events associated with CAS makes one wonder about the efficacy of neuroprotective devices or the mechanism of new DWI lesions after CAS, or both.