Patent ID: 7657324

Claim:
An implantable lead for implantation by a guidewire on or about the heart, the lead comprising: a lead body having distal and proximal ends, the lead body defining a lumen extending from a distal aperture in the distal end of the lead body toward the proximal end of the lead body; a conductor disposed within the lead body; an electrode disposed proximate the distal end of the lead body, the electrode electrically coupled to the conductor; and a seal at the distal end of the lead body, the seal having an open and a closed state, wherein when the seal is in the open state the seal receives the guidewire therethrough and when the seal is in the closed state the seal prevents fluid from entering the lumen of the lead body; wherein the seal is transitionable from the open state to the closed state and is coupled to a housing having a proximally located shoulder.