Patent ID: 8108054

Claim:
An implantable medical lead for active fixation to cardiac tissue, the lead comprising: a lead body distal portion having a distal end; a tissue fixation helical anchor coupled to the lead body distal portion and including a distal tip; and a structure having a proximal end, a distal end and a body intermediate the proximal end and distal end, the structure extending distally from the lead body distal portion, the structure being moveable relative to the lead body distal portion, the proximal end of the structure extending outwardly from the lead body distal portion at a location proximal to the distal end of the lead body distal portion, the distal end of the structure having a first radiopaque marker, and the structure being biased to project the distal end of the structure near the distal tip; wherein, when the tissue fixation helical anchor is progressively embedded in the cardiac tissue, the cardiac tissue progressively displaces the distal end of the structure proximally.