A positioning sensor for use in a medical device wherein the device has a heat-fused layer comprising a first material having a first melting temperature. The sensor has a tubular core comprising a second material having a second melting temperature that is higher than the first temperature. The core has a central through-bore extending along an axis between opposing axial ends of the core, and where the core further has a radially-outermost outermost winding surface. The sensor includes an electrically conductive coil wound on the winding surface.
