Porous electrode with enhanced reactive surface

Claim 2

An electrode implantable inside a patient, comprising: an electrode body constructed of an electrically conductive filament structure including a plurality of elongate fiber elements with diameters of at least five microns, said fiber elements bundled in close proximity with one another and forming multiple passages throughout the electrode body and open to the exterior of the body, whereby an exposed surface of the electrode body includes an exterior surface portion, and an interior surface portion along and defining said passages, with the volume occupied by the passages comprising more than one half of the total volume occupied by the electrode body; and a surface texture comprising multiple surface irregularities formed over substantially the entire exposed surface of the electrode body, thereby to substantially increase the surface area of said exposed surface as compared to an equivalent smooth surface of an identically sized electrode body.

Claim 3

The implantable electrode of claim 1 wherein: at least some of the passages have diameters in the range of from ten to fifty microns, and the surface area of said exposed surface is greater than an equivalent smooth surface of an equally sized electrode body, by a factor of at least ten.

Claim 4

The implantable electrode of claim 2 wherein: said filament structure includes at least one strand of a metallic wire packed into a compress.

Claim 5

The implantable electrode of claim 3 wherein: said filament structure is a single strand of said metallic wire, said fiber elements comprising portions of the single strand.

Claim 6

The electrode of claim 3 wherein: said irregularities are formed as a metallic texturizing layer applied to said metallic wire.

Claim 7

The electrode of claim 5 wherein: said metallic texturizing layer consists essentially of aluminum.

Claim 8

The electrode of claim 5 wherein: said metallic texturizing layer consists essentially of platinum.

Claim 9

The electrode of claim 5 wherein: said metallic texturizing layer consists essentially of titanium.

Claim 10

The electrode of claim 5 wherein: said texturizing layer is applied by vapor deposition following the formation of said compress.

Claim 11

The electrode of claim 5 further including: an adhesion enhancing underlayer between said metallic wire and said texturizing layer.

Claim 12

The electrode of claim 10 wherein: said underlayer consists essentially of titanium.

Claim 13

The electrode of claim 5 further including: an inert metallic cover layer over said metallic texturizing layer.

Claim 14

The electrode of claim 12 wherein: said cover layer is formed of a catalytic material having a low activation energy.

Claim 15

The electrode of claim 13 wherein: said catalytic material consists essentially of one of the following constituents: platinum, titanium, and a platinum-iridium alloy.

Claim 16

The electrode of claim 14 wherein: said catalytic material consists essentially of platinum.

Claim 17

The electrode of claim 15 further including: a carbon layer vapor deposited over said platinum layer.

Claim 18

The electrode of claim 3 wherein: said irregularities include multiple nodules having average diameters of less than about four microns.

Claim 19

The electrode of claim 17 wherein: the average diameter of said nodules is from one to two microns.

Claim 20

The electrode of claim 18 wherein: said irregularities further include depressions having an average diameter of about one to two microns.

Claim 21

The electrode of claim 1 wherein: said passages have average diameters in the range of from about ten microns to about one hundred fifty microns.

Claim 22

The electrode of claim 20 wherein: said passages have average diameters in the range of from ten to fifty microns.

Claim 23

An intravascular cardiac pacing lead implantable inside a patient, including: an electrode body constructed of an electrically conductive filament structure including a plurality of elongate fiber elements with diameters of at least five microns, said fiber elements being bundled in close proximity with one another and forming multiple passages throughout the electrode body and open to the exterior of the body, whereby an exposed body and open to the exterior of the body, whereby an exposed surface of the electrode body includes an exterior surface portion, and an interior surface portion disposed along and defining the passages, at least some of the passages having diameters in the range of ten to fifty microns, with the volume occupied by the passages comprising more than one half of the total volume occupied by the electrode body; a surface texturing comprising multiple surface irregularities formed over substantially the entire exposed surface of the electrode body, in sufficient size and density to provide an enlarged surface area of said exposed surface, as compared to an equivalent smooth surface of an identically sized electrode body, by a factor of at least five; a flexible electrical conductor and a flexible, biocompatible, dielectric sheath surrounding said conductor along substantially the entire length thereof; and a coupling means for electrically and mechanically joining the electrode body with respect to a distal end of the conductor, said electrode body being joined to and substantially covering a distal end of the coupling means.

Claim 24

An intravascular cardiac pacing lead implantable inside a patient, including: an electrode body constructed of an electrically conductive filament structure including a plurality of elongate fiber elements with diameters of at least five microns, said fiber elements being bundled in close proximity with one another and forming multiple passages throughout the electrode body and open to the exterior of the body, whereby an exposed body and open to the exterior of the body, whereby an exposed surface of the electrode body includes an exterior surface portion, and an interior surface portion disposed along and defining the passages, at least some of the passages having diameters in the range of ten to fifty microns, with the volume occupied by the passages comprising more than one half of the total volume occupied by the electrode body; a surface texturing comprising multiple surface irregularities formed over substantially the entire exposed surface of the electrode body, in sufficient size and density to provide an enlarged surface area of said exposed surface, as compared to an equivalent smooth surface of an identically sized electrode body, by a factor of at least five; a flexible electrical conductor and a flexible, biocompatible, dielectric sheath surrounding said conductor along substantially the entire length thereof; and a coupling means for electrically and mechanically joining the electrode body with respect to a distal end of the conductor, said electrode body being joined to and substantially covering a distal end of the coupling means.

Claim 25

A defibrillation patch electrode comprising: a first layer of interwoven, mutually perpendicular strands formed of a biocompatible, electrically conductive material; a second layer comprised of an electrically conductive filament structure contained against said first layer, said filament structure including a plurality of elongate fiber elements with diameters of at least five microns, bundled in close proximity to one another and forming multiple passages open to said first layer, an exposed surface of the filament structure including an exterior surface portion, and an interior surface portion along and defining the passages, with the volume occupied by the passages comprising more than one half of the total volume occupied by the second layer; and a surface texture comprising multiple surface irregularities formed over substantially the entire exposed surface of said filament structure, said irregularities being of sufficient size and density to provide an enhanced surface area of said exposed surface, as compared to the area of an equivalent smooth surface of an identically sized filament structure, by a factor of at least five.

Claim 26

A defibrillation patch electrode comprising: a first layer of interwoven, mutually perpendicular strands formed of a biocompatible, electrically conductive material; a second layer comprised of an electrically conductive filament structure contained against said first layer, said filament structure including a plurality of elongate fiber elements with diameters of at least five microns, bundled in close proximity to one another and forming multiple passages open to said first layer, an exposed surface of the filament structure including an exterior surface portion, and an interior surface portion along and defining the passages, with the volume occupied by the passages comprising more than one half of the total volume occupied by the second layer; and a surface texture comprising multiple surface irregularities formed over substantially the entire exposed surface of said filament structure, said irregularities being of sufficient size and density to provide an enhanced surface area of said exposed surface, as compared to the area of an equivalent smooth surface of an identically sized filament structure, by a factor of at least five.

Claim 27

The defibrillation patch electrode of claim 23 further including: a third layer of interwoven, mutually perpendicular strands formed of a biocompatible, electrically conductive material disposed opposite said first layer, with said second layer contained between the first and third layers.

Claim 28

The defibrillation patch electrode of claim 24 wherein: at least some of the passages have diameters in the range of from ten to one hundred and fifty microns.

Claim 29

An implantable device for sensing electrical activity in body tissue, including: an electrode body positionable at a select area of body tissue, said electrode body constructed of an electrically conductive filament structure including multiple elongate fiber elements having diameters of at least five microns and bundled in close proximity with one another to form multiple passages throughout the electrode body and open to the exterior of the electrode body, whereby an exposed surface of the filament structure includes an exterior surface portion and an interior surface portion along and defining said passages, with the volume occupied by the passages comprising more than one half of the total volume occupied by the filament structure; a surface texture comprising multiple surface irregularities formed over substantially the entire exposed surface of the filament structure, in sufficient size and density to provide an enhanced surface area of said exposed surface, as compared to the surface of an equivalent smooth surface of an equally sized filament structure, by a factor of at least five; and a conductor electrically associated with said electrode body for transmitting electrical pulses from said selected area of body tissue to a sensing location remote from the selected area.

Claim 30

An implantable device for sensing electrical activity in body tissue, including: an electrode body positionable at a select area of body tissue, said electrode body constructed of an electrically conductive filament structure including multiple elongate fiber elements having diameters of at least five microns and bundled in close proximity with one another to form multiple passages throughout the electrode body and open to the exterior of the electrode body, whereby an exposed surface of the filament structure includes an exterior surface portion and an interior surface portion along and defining said passages, with the volume occupied by the passages comprising more than one half of the total volume occupied by the filament structure; a surface texture comprising multiple surface irregularities formed over substantially the entire exposed surface of the filament structure, in sufficient size and density to provide an enhanced surface area of said exposed surface, as compared to the surface of an equivalent smooth surface of an equally sized filament structure, by a factor of at least five; and a conductor electrically associated with said electrode body for transmitting electrical pulses from said selected area of body tissue to a sensing location remote from the selected area.

Claim 31

The implantable device of claim 26, wherein: at least some of the passages have diameters in the range from ten to one hundred and fifty microns.