Balloon-protected carotid artery stenting - Relationship of periproceduralneurological complications with the size of particulate debris

Background-Carotid artery stenting (CAS) has been advocated as an alternati ve to endarterectomy. To prevent cerebral atheroembolism during CAS, distal balloon occlusion of the target artery increasingly is employed during the procedure. A correlation of the size of captured particles with the incide nce of periprocedural neurological complications (PNCs) has not been attemp ted. Methods and Results-In a 4-center, phase-1 trial, 54 patients (46 men; age, 69 +/-8 years) underwent 58 CAS procedures using the PercuSurge GuardWire system for distal protection. Aspirated debris was sent for histological/cy tological analysis. Stent placement was successful in all cases. Mean ballo on occlusion time was 10.4 +/-4.0 minutes (range, 3.0 to 22.0 minutes). Thr ee patients (5.2%) experienced PNCs: I prolonged reversible ischemic neurol ogical deficit that resolved in less than or equal to 48 hours, 1 stroke, a nd 1 transient ischemic attack. Relevant particles (those with an area grea ter than or equal to 10 000 mum(2)) were found in 48 aspirates (83%). The m edian number of particles, their maximum diameter, and their maximum area w ere all significantly higher in the aspirates obtained during procedures as sociated with PNCs than in aspirates obtained during procedures not associa ted with PNCs. However, pronounced overlap in the distributions (PNCs versu s no PNCs) of the number and maximum diameter of particles precluded any pr edictive inferences. In contrast, a maximum particle area > 800 000 mum(2) (>0.8 mm(2)) was associated with a 60% chance of having a PNC. Conclusions-Despite balloon protection, PNCs occurred in 5.2% of patients w ho underwent CAS procedures. The maximum area of aspirated particles seems to be an indicator of increased risk for PNCs.