Various devices are provided for improved surgical sutures systems. In general, the suture systems can allow a suture to form a secure, closed loop without tying a knot. The suture (100) can include a barbed portion (108) configured to be threaded through a hollow portion (112). The barbed portion can have a plurality of barbs (118) thereon, which can grasp onto an inner wall of the hollow portion when disposed therein to help secure the loop at a desired size. The barbs can all be oriented in one direction that corresponds to a direction of movement of the suture when the loop is being tightened. Thus, the barbs can be configured to allow for a size of the loop to be easily reduced to any desired size to approximate tissue, but can be configured to resist subsequent expansion of the loop to ensure that the tissue remains in place.