An example system for delivering an implantable heart valve is disclosed. The system includes an inner shaft having a proximal end region, a distal end region and a first coupling member disposed along a portion of the distal end region, wherein the first coupling member includes a first aperture. The system also includes a support shaft having a proximal end region, a distal end region and a second coupling member disposed along a portion of the proximal end region, wherein the second coupling member includes a stem, wherein the stem includes a groove extending circumferentially around the stem. The system also includes a locking clip coupled to the inner shaft, wherein coupling the inner shaft to the support shaft includes extending at least a portion of the locking clip through the first aperture and into at least a portion of the groove.