A mechanism can include a step feature guidewire having a guidewire with a proximal end, a distal end, and a diameter. A self-expanding element can be disposed approximate to the distal end of the guidewire and can have at least two states which include a contracted diameter and an expanded diameter. The self-expanding element can be expandable under its inherent proprieties, based at least on its original shape and the nature of the materials that make up the element. Further, the expanded diameter can be approximately 70% to 280% of the guidewire diameter. While the guidewire is designed for passing through a body lumen while treating a patient, the expanded diameter is less than any body lumen diameter the guidewire is determined to pass through.