Patent ID: 7493175

Claim:
An implantable lead configured for placement within a tunnel formed in subcutaneous non-intrathoracic tissue, comprising: a lead body; a cardiac electrode supported by the lead body, the cardiac electrode configured for one or both of sensing cardiac activity and delivering cardiac stimulation energy from a location within the tunnel; and a plurality of fixation elements disposed longitudinally along at least an electrically insulative portion of the lead body in a spaced relationship, the fixation elements configured to passively secure one or both of the cardiac electrode and the lead body in subcutaneous non-intrathoracic tissue at a plurality of longitudinally spaced fixation sites of the tunnel, the plurality of fixation elements comprising: a first set of curved tines, each curved tine of the first set comprising a first end attached to the lead body on the electrically insulative portion and a free end opposite the first end, each curved tine of the first set biased out of plane with respect to a longitudinal axis of the lead body in a first orientation to curve around some of the circumference of the lead body such that the free end points in a clockwise direction with respect to the circumference of the lead body at which the first end is attached to the lead body to resist rotation of the lead in the clockwise direction; and a second set of curved tines, each curved tine of the second set comprising a first end attached to the leady body on the electrically insulative portion and a free end opposite the first end, each curved tine of the second set biased out of plane with respect to the longitudinal axis of the lead body in a second orientation to curve around some of the circumference of the lead body such that the free end points in a counterclockwise direction with respect to the circumference of the lead body at which the first end is attached to the lead body to resist rotation of the lead in the counterclockwise direction.