A catheter system can be used to remove obstructions, deliver implantable devices or substances, and/or restore flow through body lumens. The system can include an outer shaft having a lumen, sidewall, and a longitudinal window in the sidewall, an inner shaft disposed within the lumen, and an expandable member having a first end coupled to the outer shaft and a second end coupled to the inner shaft through the window. The expandable member can be positioned adjacent to a target region while in the collapsed configuration. The expandable member can be expanded to an expanded configuration by relative movement of the outer shaft and the inner shaft.