Guidewires suitable for use in a system for implanting a lung volume reduction device are disclosed. The guidewire includes an outer sheath having proximal and distal ends, and comprising a proximal section, a transition section, and a distal section. The proximal section extends from the proximal end of the sheath to the transition section, and the distal section extends from the transition section to the distal end of the sheath. The distal section defines a bore extending from the transition section to the distal end of the sheath and an inner core having proximal and distal ends. The inner core extends through the bore of the distal section of the sheath, wherein the inner core is fixed to the sheath at the transition section, and wherein the distal end of the inner core is fixed to the distal end of the sheath at the distal end of the sheath.