Flat wire helix electrode used in screw-in cardiac stimulation leads

摘要

An implantable endocardial lead for use with a cardiac stimulation device includes an active fixation helix disposed at the distal end of the lead. The helix is constructed of flat wire having a non-circular cross section. The helix may be fixed or movable between a retracted position fully within the lead and an extended position advanced beyond the distal end of the lead.