The present invention provides a medical device having an catheter body defining proximal and distal portions, and a guidewire lumen at least partially disposed within and movable within the catheter body. The medical device may include an expandable element defining a proximal end and a distal end, wherein the proximal end is coupled to the distal portion of the catheter body and the distal end is coupled to the guidewire lumen. In addition, an actuator element may be coupled to the guidewire lumen for longitudinal movement thereof, and a tensioning element may further be coupled to the guidewire lumen to bias the guidewire lumen and/or the expandable element towards a particular geometric configuration.