Abstract: Systems for less invasive medical procedures comprise a filter device mounted on an integrated guiding structure and an aspiration catheter. These components can be used together or separately, and the system can be used with other medical devices that are designed for less invasive procedures, such as procedures in a patient's vasculature. The filter device can involve improved torque coupling with a torque coupler associated with a resilient member that correspondingly also provides increased flexibility relative to an overtube that forms a tube for the remaining portions of the device. An actuation tool for the filter device used a systematic loading procedure for proper loading of the corewire and overtube into the actuation tool. A fiber cartridge comprises fibers loaded as a bundle into the cartridge for delivery with the ends of the fibers respectively bonded to radiopaque markers that can be visualized to come together when the filter is properly deployed.