Implantable extravascular electrical stimulation lead having improved sensing and pacing capability

An implantable medical electrical lead comprising:

• an elongated lead body having a distal portion and a proximal end;
• a connector at the proximal end of the lead body;
• a defibrillation electrode located along the distal portion of the lead body, wherein the defibrillation electrode includes a first electrode segment and a second electrode segment spaced proximal to the first electrode segment by approximately 1-3 centimeters (cm);
• and
• at least one pace/sense electrode located between the first electrode segment and the second electrode segment of the defibrillation electrode.

An extravascular implantable cardioverter-defibrillator system comprising:

• an implantable cardioverter-device (ICD) that includes a therapy module configured to generate and deliver electrical stimulation therapy;
• and
• an extravascular implantable medical electrical lead electrically coupled to the therapy module, wherein the lead comprises:
• an elongated lead body having a distal portion and a proximal end;
• a connector at the proximal end of the lead body;
• a defibrillation electrode located along the distal portion of the lead body, wherein the defibrillation electrode includes a first electrode segment and a second electrode segment spaced proximal to the first electrode segment by a distance;
• and
• at least one pace/sense electrode located between the first electrode segment and the second electrode segment of the defibrillation electrode.

An extravascular implantable cardioverter-defibrillator (ICD) system comprising:

• an extravascular implantable medical electrical lead that includes:
• an elongated lead body having a distal portion and a proximal end;
• a connector at the proximal end of the lead body;
• a plurality of defibrillation electrode segments located along the distal portion of the lead body, wherein the plurality of defibrillation electrode segments includes at least a first defibrillation electrode segment and a second defibrillation electrode segment spaced proximal to the first defibrillation electrode segment by a distance;
• a first pace/sense electrode located distal to the first defibrillation electrode segment;
• a second pace/sense electrode located proximal to the second defibrillation electrode segment;
• and
• a plurality of conductors extending within the elongated body from the connector to the distal portion, wherein each of the first defibrillation electrode segment, the second defibrillation electrode segment, the first pace/sense electrode, and the second pace/sense electrode are coupled to a different one of the plurality of conductors within the lead body;
• and
• an ICD coupled to the extravascular lead, the ICD including:
• a therapy module configured to generate and deliver electrical stimulation therapy;
• and
• a switch module configured to selectively couple the therapy module to an electrode vector in which both the first and second defibrillation electrode segments simultaneously function as a cathode for delivery of defibrillation therapy.