Patent ID: 8666508
Filing Date: 2014-03-04
Classification: A61N

Abstract:
1. An implantable medical lead, comprising: a helically-shaped inner electrode conductor wire disposed within an interior lumen of the lead, the inner electrode conductor wire comprising a plurality of co-radially wound wire filars wound to have a first pitch, each wire filar of the inner electrode conductor wire comprising a drawn-filled tube filled with an inner core of a first type of material having a first resistance, the inner electrode conductor wire having a first outer diameter; a helically-shaped outer electrode conductor wire disposed about and spaced radially apart from the inner electrode conductor wire, the outer electrode conductor wire comprising a plurality of co-radially wound wire filars wound to have a second pitch that is less than the first pitch, each wire filar of the outer electrode conductor wire comprising a drawn-filled tube filled with an inner core of a second type of material having a second resistance that is less than the first resistance, the outer electrode conductor wire having a second outer diameter that is greater than the first outer diameter; at least one insulation layer disposed radially about the inner electrode conductor wire; and wherein the outer electrode conductor wire is configured to have an inductance sufficient to dissipate electromagnetic energy received on the lead from magnetic resonance imaging procedures, the inductance of the outer electrode conductor wire based at least in part on the second pitch and the second outer diameter.