A catheter handle assembly includes a holder having a proximal end and a distal end. An electrode sheath carrier is arranged at the distal end of the holder. A shape imparting element carrier is removably mountable to the proximal end of the holder, the shape imparting element carrier having at least one mounting formation for mounting at least a part of a shape imparting element. A slide is displaceably arranged in the holder with a distal end of the slide mounting the electrode sheath carrier and a proximal end of the slide terminating in proximity to the shape imparting element carrier.