Role of the distal balloon protection technique in the prevention of cerebral embolic events during carotid stent placement

Background and Purpose-We sought to quantitatively and qualitatively evalua te the release of atheromatous plaque debris induced by carotid stenting pr ocedures. Methods-Eight patients with severe carotid atheromatous stenoses were treat ed by stent implantation under distal balloon protection, Blood samplings w ere obtained after stent deployment in the blood pooled below the inflated protection balloon. The samples were centrifuged and evaluated for plaque d ebris with the use of light microscopy. The debris release was quantitative ly estimated by dividing the total volume of debris obtained by the mean de bris size. Five patients without endovascular procedure were used as a cont rol group. Results-The 2 main debris types found were nonrefringent cholesterol crysta ls (4 to 389 mum; 115 to 8697 in number) and lipoid masses (7 to 600 mum; 3 41 to 34 000 in number). There was a statistically significant difference c ompared with the samples obtained in the control group (P = 0,017). Conclusions-Blood samples collected during stent implantation procedures co ntain a large quantity of atheromatous plaque debris. This emphasizes the r ole of distal protection techniques in avoiding migration of this plaque ma terial into the cerebral circulation.