Cardiac vein lead with flexible anode and method for forming same

A cardiac pacing lead, comprising:

• an elongated lead body extending from a proximal end to a distal end, the lead body having an outer insulative sheath;
• a first electrode positioned at the distal end of the lead body;
• and
• a second electrode spaced proximally from the first electrode and positioned within the outer insulative sheath, wherein the second electrode includes a plurality of filars having corresponding distal ends, each of the distal ends being fixed to a corresponding adjacent filar of the plurality of filars, wherein the plurality of filars includes a first filar having a first filar distal end, a second filar having a second filar distal end, a third filar having a third filar distal end, and a fourth filar having a fourth filar distal end, and wherein the first filar distal end is trimmed and fixedly engaged with the second filar to be positioned proximal from the second distal end, the second filar distal end is trimmed and fixedly engaged with the third filar to be positioned proximal from the third distal end, the third filar distal end is trimmed and fixedly engaged with the fourth filar to be positioned proximal from the fourth distal end.

A cardiac pacing lead, comprising:

• an elongated lead body extending from a proximal end to a distal end, the lead body having an outer insulative sheath;
• a first electrode positioned at the distal end of the lead body;
• and
• a second electrode spaced proximally from the first electrode and positioned within the outer insulative sheath, wherein the second electrode includes a plurality of filars having corresponding distal ends, each of the distal ends being fixed to a corresponding adjacent filar of the plurality of filars, wherein the second electrode has a first surface area of approximately 30 to 40 square millimeters and the first electrode has a second surface area of approximately 5 to 6 square millimeters.

A cardiac pacing lead, comprising:

• an elongated lead body extending from a proximal end to a distal end, the lead body having an outer insulative sheath;
• a first electrode positioned at the distal end of the lead body;
• and
• a second electrode spaced proximally from the first electrode and positioned within the outer insulative sheath, wherein the second electrode includes a plurality of filars having corresponding distal ends, each of the distal ends being fixed to a corresponding adjacent filar of the plurality of filars and positioned proximal to a distal end of the adjacent filar, wherein the second electrode is formed from a bifilar platinum iridium coil.

A method of forming a cardiac lead having an elongated lead body extending from a proximal end to a distal end, the lead body having an outer insulative sheath, comprising the steps of:

• positioning a first electrode along the distal end of the lead body;
• positioning a second electrode within the outer insulative sheath to be spaced proximally from the first electrode;
• advancing the second electrode along a mandrel so that a distal end portion of the second electrode is engaged against a handle of the mandrel to form fixedly engaged compressed filars;
• and
• fixedly coupling corresponding distal ends of a plurality of filars corresponding to the compressed filars to a corresponding adjacent filar of the plurality of filars.