A catheter apparatus defining a first lumen with a first internal diameter, the catheter apparatus further comprising a shaping structure having a distal end and a proximal end and a length therebetween, the shaping structure being moveable between a delivery state having a first helical shape, and a deployed state having a second helical shape. A deployment member having a second lumen with a second internal diameter, a first portion of the deployment member being positioned within the first lumen and having a third outside diameter sized to enable the deployment member to slide within the first lumen, the deployment member being operably coupled to the distal end of the shaping structure and being configured such that distal axial movement of the deployment member places the shaping structure in the delivery state, and proximal axial movement of the deployment member places the shaping structure in the deployed state.
