than markers 29 30 and 31 on catheter shaft 21 and marker 36 on sheath 24 thereby to facilitate rapid differentiation between filter 32 sheath 24 and catheter shaft 21 referring now to fig5 a 5f a method of using catheter 20 of fig1 is described to protect against embolism during iliac stenting with respect to fig5 a the patient is prepped and the femoral artery is accessed percutaneously or via cutdown and an introducer not shown is placed to establish access to the patient 39 s vessel v guidewire 35 is placed across lesion l and catheter 20 then is advanced along the guidewire until the stent is disposed across lesion l as determined by fluoroscopic visualization of markers 30 and 31 blood flow f is towards the operator i e from the distal to proximal direction relative to device 10 once the position of catheter 20 is confirmed sheath 24 is retracted proximally while holding catheter shaft 21 stationary as depicted in fig5 b sheath 24 is retracted to expose balloon 27 stent 37 and filter 32 as the sheath is retracted proximal to filter 32 struts 33 cause the filter to deploy so that filter mesh 34 spans the vessel proper retraction of sheath may be confirmed by using a fluoroscope to determine the relative positions of markers 29 and 27 balloon 27 then may be inflated by infusing contrast saline or carbon dioxide through.