A percutaneous device including a temporary valve (104) attached to a sheath (101), the sheath (101) having an inverting section for delivery and removal thereof from a blood vessel. The sheath (101) is inverted for delivery, housing the valve between inverted layers thereof. To deploy said valve, the sheath (101) is everted to position the temporary valve (104) on an outer surface (117) thereof. The temporary valve (104) and sheath (101) are reversibly movable between inverted and deployed configurations. Upon eversion, the temporary valve (104) assumes a radially expanded canopy (106) shape having an outer diameter selected to contact the vessel wall and allow blood flow in only one direction (1, 2). The temporary valve (104) may be removed by releasing one end of the valve from the sheath (101), flattening the temporary valve (104) along the longitudinal axis of the sheath (101). Also provided is a temporary valve (104) system comprising a dilator (160) for inverting and everting the sheath (101), said dilator (160) being removably connected to the sheath (101).
