Electrode lead
Implantable electrode lead for stimulation in or on the heart, comprising a body having an insulating and sealing outer surface, at least one electrical connection between an outwardly electrically active region having a connecting unit for the electrical connection to a cardiac pacemaker, cardioverter/defibrillator or other suitable electrically active implantable device, and an active or passive fixation. To reduce the electrical resistance while, at the same time, providing for a long life, the outwardly electrically active regions are manufactured with a component of high bioresistance, biocompatibility and non-toxicity, and a component with low electrical resistance.
1. An implantable electrode lead ( 1 ) for stimulation in or on the heart,
comprising:
a long stretched-out electrode body ( 3 ) having a distal and a proximal end,
at least one connecting unit ( 4 a , 4 b , 4 c ) for the electrical connection to an electrically active implantable device at the proximal end,
a fixation device ( 6 b ) at the distal end,
a largely electrically insulating and sealing outer surface ( 17 ) situated between the distal and proximal end,
at least one electrically conductive connection ( 16 ) between the proximal and distal end, and
at least one outwardly electrically active region ( 5 a , 5 b ) in the distal region of the long stretched-out electrode body ( 3 ) that is electrically connected to one of the electrically conductive connections ( 16 )
wherein:
the at least one outwardly electrically active region is composed of at least one element of “Drawn Filled Tube” (DFT) comprising an element of a helically wound DFT ribbon ( 13 a ), said element comprising:
an enveloping component ( 30 ) of high bioresistance, biocompatibility and non-toxicity, and
a core component ( 31 ) with low electrical resistance, said core component ( 31 ) being a core of said element and said core component being enveloped by said enveloping component ( 30 );
the DFT ribbon ( 13 a ) of the at least one electrically active region ( 5 a , 5 b ) has in the distal region a radially outwardly oriented semi-circular surface ( 32 ); and
the semi-circular surface ( 32 ) has a radius significantly larger than half the diameter of the electrode body ( 3 ).
2. An implantable electrode lead according to claim 1 , wherein the enveloping component ( 30 ) of high bioresistance, biocompatibility and non-toxicity is platinum, iridium, or an alloy of the two materials.
3. An implantable electrode lead according to claim 1 , wherein the core component ( 31 ) of low electrical resistance consists of an element from the vanadium group (5 th subgroup of the classification of elements) or copper group (11 th subgroup of the classification of elements).
4. An implantable electrode lead according to claim 3 , wherein the core component ( 31 ) of low electrical resistance is tantalum, niobium or gold.
5. An implantable electrode lead according to claim 1 , wherein the thickness ratio between the bioresistant, biocompatible and non-toxic enveloping component ( 30 ) and the core component ( 31 ) of low electrical resistance is 1:3 to 1:40.
6. An implantable electrode lead according to claim 1 , wherein the thickness ratio in an axial direction of the electrode ( 1 ) between the bioresistant, biocompatible and non-toxic enveloping component ( 30 ) and the core component ( 31 ) of low electrical resistance is between 1:20 and 1:40, preferably between 1:25 and 1:30, most preferably between 1:27 and 1:29.
7. An implantable electrode lead according to claim 1 , wherein the ratio in a radial direction of the electrode ( 1 ) between the bioresistant, biocompatible and non-toxic enveloping component ( 30 ) and the core component ( 31 ) of low electrical resistance is between 1:2 and 1:10, and preferably between 1:3 and 1:8.
8. An implantable electrode lead according to claim 1 , wherein the electrically active implantable device is one of a pacemaker and cardioverter/defibrillator.
9. An implantable electrode lead according to claim 1 , wherein the electrically active regions ( 5 a , 5 b ) in the distal region deliver one of a stimulation pulse, cardioversion pulse and defibrillation pulse.
10. An implantable electrode lead according to claim 1 , wherein the fixation device ( 6 b ) in the distal region is one of a passive anchoring and an active anchoring.
11. An implantable electrode lead according to claim 10 , wherein the active anchoring ( 6 b ) is an electrically active region.
12. An implantable electrode lead according to claim 1 , wherein the electrically conductive connection ( 16 ) between the proximal connecting unit ( 4 a , 4 b , 4 c ) and the at least one electrically active region is selected from a round wire, a DFT wire, an electrically conductive ribbon, an electrically conductive DFT ribbon, an electrically conductive cable, and an electrically conductive DFT cable.
13. An implantable electrode lead according to claim 1 , wherein the electrode body ( 3 ) consists of an inner ( 18 ) and an outer layer ( 17 ) of biostable synthetic material.
14. An implantable electrode lead according to claim 13 , wherein the outer layer ( 17 ) is a silicone rubber.
15. An implantable electrode lead according to claim 13 , wherein the inner layer ( 18 ) is composed of polyurethane.
16. An implantable electrode lead according to claim 1 , wherein the electrically active regions ( 5 a , 5 b ) in the distal region are embedded in the outer surface.