Filter-protected versus unprotected carotid artery stenting: a randomised trial

Area of Science:

• Neurology
• Vascular Surgery
• Medical Imaging

Background:

• Carotid artery stenting (CAS) is a procedure to treat symptomatic carotid artery stenosis.
• Embolisation to the brain is a potential complication during CAS.

Purpose of the Study:

• To investigate whether using a filter during CAS reduces embolisation to the brain.
• To compare brain lesion incidence and microembolisation rates between filter-protected and unprotected CAS.

Main Methods:

• Thirty patients with >70% symptomatic carotid artery stenosis were randomized to filter-protected or unprotected CAS.
• Diffusion-weighted magnetic resonance imaging (DWI) assessed new brain lesions before and after CAS.
• Transcranial Doppler (TCD) monitored high-intensity transient signals (emboli) during the procedure.

Main Results:

• No significant differences in patient demographics or presenting symptoms between groups.
• Filter-protected CAS showed a trend towards more new DWI lesions at 1-3 hours (29% vs 18%) and 30 days (26% vs 12%).
• Significantly higher total and particulate emboli counts were observed on TCD during filter-protected CAS (p=0.01 and p=0.03).

Conclusions:

• Filter-protected CAS is associated with increased new brain lesions on DWI and higher microembolisation rates on TCD.
• The clinical significance of these findings warrants further investigation.
• Current evidence suggests filter protection may not reduce, and could potentially increase, embolic events during CAS.