Abstract: A lead adapted to be located within the cardiac vasculature is disclosed. The lead may be readily steered to a desired location within the cardiac vasculature to thereafter be securely located at a desired pacing site. The lead is provided with an improved electrode assembly located at its distal tip. The electrode assembly includes a fixation helix and a guidewire-like projection, both extending from the distal end of the lead body. The fixation helix, which may serve as all or part of the active electrode surrounds a structure corresponding to the distal end of a conventional guidewire. The fixation helix is mounted around the guidewire tip so that the sharpened tip of the helix lies closely adjacent to the guidewire tip, in a region of the guidewire tip which is sufficiently flexible to allow it to be moved away from the sharpened tip of the helix.