A lead header for an implantable medical lead is in the form of a metal sheet bent to form a metal tube having a lumen. The metal sheet has a protruding portion that extends radially inwardly into the lumen. The protruding portion may be lip arranged in connection with one of the longitudinal sides of the metal sheet that is bent to protrude radially inwardly into the lumen, or it may be a dent formed in the metal sheet. In either case, the protruding portion is configured to transform a rotation of a helical fixation element of the medial lead that is at least partly present in the lumen into a longitudinal movement of the helical fixation element relative to the lead header.
