Abstract: An expandable implant can be used obstruct or reduce flow in arteries, veins, fusiform aneurysms, parent vessels of saccular aneurysms, paravalvular leak pathways, biological conduits, or other blood-containing, fluid-containing, or biological spaces. A balloon catheter delivery system can be used to deliver the implant. This can include an over-the-guidewire balloon catheter delivery system. The catheter portion of the system can deliver the expandable metallic implant to the treatment site, and the balloon portion of the system can expand the expandable metallic implant at the treatment site. The deliverability of the expandable implant devices can be optimized by reducing the overall diameter of the folded and pleated expandable metallic implant, and shortening the length of the rigid device segments. The risk of implant migration can be reduced by adding features to the expandable metallic implant implants that increase sliding friction in tissue.