A system used in a blood vessel when an interventional procedure is being performed in a stenosed or occluded region to capture any embolic material which may be created and released into the bloodstream during the procedure. The system includes filtering elements which are capable of occluding a blood vessel distal to an interventional procedure site, while enabling the blood to flow past the occlusion and filtering the blood to capture embolic material which may be released into the blood during a therapeutic interventional procedure. The filtering elements include an expandable member which is capable of being expanded distal to the area of treatment at the interventional procedure site for occluding the blood vessel and for enabling the blood to pass therethrough while preventing emboli from passing therethrough. The system also includes a sheath movable distally and proximally to enable the filtering elements to expand into position distal to the interventional procedure site for capturing embolic material and to collapse the filtering elements to retain the captured embolic material therein.
