Periprocedural embolic events related to carotid artery stenting detected by diffusion-weighted MRI: Comparison between proximal and distal embolus protection devices

Purpose: To evaluate and compare the efficacy of proximal versus distal embolus protection devices (EPD) during carotid artery angioplasty/stenting (CAS) based on diffusion-weighted magnetic resonance imaging (DW-MRI). Methods: Forty-four patients (31 men; mean age 68 years, range 48-85) underwent protected CAS and had DW-MRI before and after the intervention. The cohort was analyzed according to the type of EPD used: a proximal EPD was deployed in 25 (56.8%) patients (17 men; mean age 66 years, range 48-85) and a distal filter in 19(14 men; mean age 70 years, range 58-79). Fifteen (60.0%) patients with proximal protection were symptomatic of the target lesion; in the distal protection group, 10 (52.6%) were symptomatic. Results: New lesions were seen on the postinterventional DW-MRI in 28.0% (7/25) of the proximal EPD group versus 32.6% (6/19) of those with a distal filter (p=NS). The majority were clinically silent. The new lesions in the vascular territory of the stented carotid artery in the group as a whole and per patient were fewer in the proximal EPD group (p=NS). No significant differences were noted in the T2 appearance of the new lesions or the number of new lesions observed away from the vascular territory of the stented artery. Conclusion: Proximal embolus protection devices show a nonsignificant trend toward fewer embolic events, which warrants large-scale studies. Furthermore, proximal protection devices can be useful to control and treat acute in-stent thrombosis. © 2007 by the International Society of Endovascular Specialists.