A percutaneous thrombus extraction device for removing a thrombus from within a blood vessel includes a flexible outer sheath defining a first passage between a proximal end and a distal end. An inner sheath is movably positionable within the first passage. The inner sheath defines a second passage between a proximal end and a distal end. The inner sheath is moveable in a radial direction between a collapsed configuration and an expanded configuration along a length of the inner sheath defined between the proximal end and the distal end. A catheter is movably positionable within the second passage, and has an expandable body at a distal end portion of the catheter. The expandable body is movable between a collapsed configuration and an expanded configuration.