Patent ID: 8738153

Claim:
An extension for a therapy delivery element configured to be implanted into a living body, the extension comprising: a distal connector configured to electrically couple to a proximal end of the therapy delivery element; an extension body attached to the connector, the extension body including: a stylet coil including a stylet coil lumen, the stylet coil extending within the extension body to the connector; a conductor assembly including a plurality of insulated electrical conductors braided in a tubular braided configuration around the stylet coil and electrically coupled to the connector, the tubular braided configuration including the plurality of insulated electrical conductors braided with one another, the conductor assembly including an inner lumen with a diameter greater than an outside diameter of the stylet coil, wherein the inner lumen of the conductor assembly is separated from the stylet coil by a gap with the extension body in a relaxed condition, wherein axial elongation of the extension body reduces an inner diameter of the conductor assembly to close the gap and cause the conductor assembly to constrict around the stylet coil; and a low durometer insulator extending around the conductor assembly; and a stylet sized to slide freely within the stylet coil lumen during implantation of the extension with respect to the living body.