Patent ID: 8103358

Claim:
A medical delivery system comprising: a mapping guidelet insertable through a lumen of a medical electrical lead, wherein the mapping guidelet comprises: a conductive elongated member extending from a proximal end to a distal end; insulative material surrounding the elongated member, wherein the insulative material comprises hydrolytically stable polyimide; wherein the elongated member comprises a conductive distal segment located closer to the distal end than to the proximal end of the elongated member; and wherein the elongated member further comprises a conductive proximal segment located closer to the proximal end than to the distal end of the elongated member, wherein the conductive proximal segment is electrically coupled to the conductive distal segment and is configured for sampling electrical values therefrom with a programmer; wherein the mapping guidelet further comprises a conductive coil electrically coupled to and surrounding at least a portion of the distal segment of the elongated member, wherein the insulative material further surrounds at least a first portion of the coil such that the first portion of the coil is disposed between the insulative material and the elongated conductive member, and further wherein at least a second portion of the coil is uninsulated so as to be operable for use in measuring electrical values of body tissue; and wherein the mapping guidelet when inserted in the lumen of the medical electrical lead is locatable therein such that at least a portion of the coil is located beyond a distal end of the medical electrical lead.