Routine Use of Debris Aspiration Before Retrieval of Distal Filter Protection Devices in Carotid Arterial Stenting: Analysis of Captured Debris and Evaluation of Clinical Results

BACKGROUND: Distal filter protection allows for continuous cerebral perfusion during carotid artery stenting (CAS), although a higher risk of debris migrating into the cerebral arteries compared with other protection systems has been reported. OBJECTIVE: To improve the extent of debris capture, we used routine aspiration of blood located proximal to the filter in the internal carotid artery blood column before retrieval of the filter device. METHODS: Of 71 CAS procedures with distal filter protection, routine aspiration was performed in 41 procedures. The size and number of debris particles in each aspirated blood sample were measured under a stereoscopic microscope in 30 consecutive procedures with routine aspiration. Occurrence of periprocedural neurological events was compared between 41 procedures with routine aspiration and the other 30 without routine aspiration. RESULTS: In the aspirated blood, debris particles ≥500 μm and ≥1000 μm in the longest diameter were observed in 30 (100%) and 28 (93.3%) procedures, respectively. The number of particles ≥1000 μm was significantly larger in the second through fourth blood aspirates vs the first aspirate (P < .05). Occurrence of periprocedural neurological events was significantly less frequent in the routine aspiration group (0 of 41 procedures) than in the conventional method group (7 of 30 procedures) (P < .05). CONCLUSION: The use of routine aspiration during CAS with distal filter protection possibly reduced periprocedural neurological events by increasing the proportion of debris captured. To improve the capture of debris particles, at least 4 repeated aspirations are advisable during each CAS procedure.