Focal ischemia of the brain after neuroprotected carotid artery stenting.

OBJECTIVES: This study sought to assess the incidence of cerebral ischemia in nonselected patients undergoing neuroprotected carotid angioplasty and stenting (CAS) without preceding multiple-vessel diagnostic angiography.
BACKGROUND: Protection devices to prevent distal embolization during CAS are presently under clinical investigation. Diffusion-weighted magnetic resonance imaging (MRI) visualizes recent ischemia of the brain and may aid in assessing the efficacy of protection devices.
METHODS: Elective CAS was performed in 42 consecutive patients (15 female, 27 male; mean age, 67 +/- 9 years) using six different types of cerebral protection systems. All patients underwent MRI of the brain before and after a total of 44 interventions.
RESULTS: Placement and retrieval of the devices and stent deployment was achieved in all procedures. New ischemic foci were seen on postinterventional MRI in 10 cases (22.7%). One patient had sustained a major stroke, whereas no adverse neurological sequelae were associated with the other nine procedures. In the latter, one to three foci (maximum area 43.0 mm(2)) were detected in cerebral regions subtended by the ipsilateral carotid artery in eight cases and by the contralateral carotid artery in one case. In the stroke patient, 12 ischemic foci (maximum area 84.5 mm(2)) were exclusively located in the contralateral hemisphere. Follow-up MRI at 4.1 months (median, n = 7) identified residuals of cerebral ischemia only in this patient.
CONCLUSIONS: Neuroprotected CAS is associated in about 25% of cases with predominantly silent cerebral ischemia. Our findings suggest manipulation of endoluminal equipment in the supraaortic vessels to be a major risk factor for cerebral embolism during neuroprotected CAS.