Abstract: A device for containing emboli within a left atrial appendage of a patient includes a frame that is expandable from a reduced cross section to an enlarged cross section and a slider assembly. The frame extends between a proximal hub and a distal hub, and the slider assembly is coupled to the distal hub of the frame. The slider assembly includes a guide tube that has a channel extending proximally away from the distal hub, and a nut. The nut is longitudinally moveable within the channel of the guide tube over a predetermined distance relative to the guide tube. The nut is operable to be releasably coupled with an elongate core, and movement of the nut relative to the guide tube is at least partially limited by interference between a portion of the nut and a portion of the guide tube.