Subcutaneous electrode with improved contact shape for transthorasic conduction

1. An implantable lead electrode assembly comprising:

an electrode having a first face and a second face;

a backing layer disposed over the first face of the electrode; and

a flexible fin disposed on the backing layer, the fin extending away from the first face of the electrode, the fin including a rigid head and flexible connector, the flexible connector attaching the rigid head to the backing layer, the flexible fin configured such that with the application of pressure against the fin, the fin moves between an extended position in which the fin has a first appendage height to a folded position in which the appendage height of the fin is reduced, the fin moving back to the extended position when the pressure is released; wherein the electrode, backing layer, and fin are adapted for implantation in a patient.

2. The implantable lead electrode assembly of claim 1 , wherein the flexible connector is adapted such that the fin moves, upon application of lateral pressure, from a first position in which the rigid head extends substantially perpendicular from the electrode to a second position in which the rigid head is substantially parallel to the electrode.

3. An implantable lead electrode assembly comprising:

an electrode having a first face and a second face;

a backing layer disposed over the first face of the electrode; and

an appendage disposed on the first face of the electrode and extending from the first face of the electrode through the backing layer, wherein the appendage does not extend beyond the second face of the electrode; wherein the electrode, backing layer, and appendage are adapted for implantation in a patient.

4. The lead electrode assembly of claim 3 , wherein the appendage includes a rod having first and second extensions and a loop therebetween, wherein the first and second extensions are attached to the first face of the electrode and are covered by the backing layer, and the loop extends through an opening in the backing layer.

5. The lead electrode assembly of claim 3 , wherein the appendage is made of platinum or titanium.

6. An implantable lead electrode assembly for use with an implantable cardioverter-defibrillator subcutaneously implanted outside a patient's ribcage between the third and twelfth ribs, wherein the lead electrode assembly comprises:

an electrode having a proximal end and a distal end, and top and bottom surfaces;

a backing layer positioned over the top of the electrode; and

a fin;

wherein the backing layer forms the fin and the fin projects from the backing layer, the backing layer including a first backing region having a first edge and a second backing region having a second edge; the first and second backing regions separated by an indented fin-forming region; the fin-forming region divided into first and second fin sides, wherein the backing layer is attached to the electrode such that the first and second edges of the first and second backing regions meet, and the fin-forming region folds to form the projecting fin; wherein the electrode, backing layer, and fin are adapted for implantation in a patient.

7. The lead electrode assembly of claim 6 , further comprising a reinforcing polymer between the first and second fin sides.

8. An implantable lead electrode assembly for use with an implantable cardioverter-defibrillator subcutaneously implanted outside a patient's ribcage between the third and twelfth ribs, wherein the lead electrode assembly comprises:

an electrode having a proximal end and a distal end, and top and bottom surfaces;

a backing layer positioned over the top of the electrode; and

a fin having first and second sides, and the first and second sides are connected at a bottom and top of the fin, such that the fin is substantially tubular;

wherein the backing layer forms the fin and the fin projects from the backing layer; wherein the electrode, backing layer, and fin are adapted for implantation in a patient.

9. The lead electrode assembly of claim 8 , wherein the fin has a proximal and a distal end, wherein the first and second sides of the fin are connected along a length of the proximal end such that the fin is closed at the proximal end and open at the distal end.

10. The lead electrode assembly of claim 9 , wherein the proximal end of the fin is sloped.

11. An implantable lead electrode assembly comprising:

an electrode having a discharging face and an opposing face, and proximal and distal ends;

a backing layer attached to the opposing face of the electrode, the backing layer having a base portion and an integral fin;

a cover attached to the backing layer, the cover enclosing the backing layer, fin, opposing face of the electrode, and at least a portion of the discharging face of the electrode; and

a reinforcing polymer disposed between the fin and cover;

wherein the fin extends beyond the base portion of the backing layer.

12. An implantable lead electrode assembly comprising:

an electrode having a first face and a second face;

a backing layer disposed over the first face of the electrode; and

an appendage disposed on the first face of the electrode and extending through the backing layer, the appendage including a rod having first and second extensions and a loop therebetween, wherein the first and second extensions are attached to the first face of the electrode and are covered by the backing layer, and the loop extends through an opening in the backing layer; wherein the electrode, backing layer, and appendage are adapted for implantation in a patient.