During manufacture a marker element is formed over a selected region of a catheter body. A length of heat shrink tubing is disposed over the selected region of the catheter body including the marker element. The catheter assembly is heated causing the heath shrink tubing to constrict in at least a longitudinal direction, forming a mechanical interlock between the marker element and the catheter body at least at one end of the marker element. The heat shrink tubing is later removed. A similar process may be used when bonding a distal tip to a distal end of the catheter body. This process may be used to provide a low profile catheter body even after a marker element has been added.