The present invention relates to a delivery system, comprising an inner shaft having a proximal end, a distal end, and a central lumen for receiving a guidewire extending from the proximal end to the distal end； a middle shaft slidably disposed over the inner shaft； an outer sheath disposed over the middle shaft； a stent disposed over the middle shaft, the stent being configured to shift between a collapsed configuration and an expanded configuration； a shuttle sheath coupled to the inner shaft by a distal coupling mechanism, the shuttle sheath configured to be disposed over the stent when the stent is in the constrained configuration； and wherein distal advancement of the inner shaft advances the shuttle sheath distally so that the stent shifts to the expanded configuration.
