DETECTION/STIMULATION IMPLANTABLE MICROLEAD INCORPORATING AN ANTI-INFLAMMATORY AGENT

• US 20140364793A1
• Filed: 06/09/2014
• Published: 12/11/2014
• Est. Priority Date: 06/11/2013
• Status: Active Grant

• Current Assignee: Sorin CRM SAS (MicroPort Scientific Corp.)
• Original Assignee: Sorin CRM SAS (MicroPort Scientific Corp.)
• Inventors: D'HIVER, Philippe
• Granted Patent: US 9,827,354 B2
• Time in Patent Office: Days
• US Class Current: 604/20
• CPC Class Codes: A61L 31/16 Biologically active materials, e.g. therapeutic substances A61L31/047 takes precedence
• CPC Class Codes: A61N 1/05 for implantation or insertion into the body, e.g. heart electrode A61N1/06 takes precedence
• CPC Class Codes: A61N 1/0568 with drug delivery
• CPC Class Codes: A61N 2001/0585 Coronary sinus electrodes

Abstract

A microlead includes a conductive cable formed by a strand of microcables, each microcable being formed of a strand of individual metallic wires. The microlead also includes an insulation layer sheathing the cable. The microlead further includes at least one exposed area formed in the insulation layer so as to form a corresponding electrode of the microlead. The microlead further includes a pharmacologically active agent (e.g., an anti-inflammatory agent) configured to gradually be released into the environment of the microlead after implantation of the microlead. The pharmacologically active agent may be a soluble material. An interstitial space, delimited by the inner wall of the insulation layer and existing in the remainder between the wires of each microcable, is filled with the pharmacologically active agent.

Claims

1. A detection/stimulation microlead for implantation in venous, arterial or lymphatic networks and having an active distal portion devoid of central lumen, the microcable comprising:

an electrically conductive cable formed by a strand of microcables, each microcable being formed of a strand of individual metallic wires;

an insulation layer of an electrically insulating material, sheathing the cable;

at least one exposed area formed in the insulation layer so as to form a corresponding electrode of the microlead;

an interstitial space defined by an internal wall of the insulation layer and in the remainder between the wires of each microcable; and

a pharmacologically active agent present in the interstitial space and configured to be gradually released into the environment of the microlead after implantation thereof, the agent released at the at least one exposed area formed in the insulation material.

2. The microlead of claim 1, wherein the pharmacologically active agent is soluble.

3. The microlead of claim 2, wherein the pharmacologically active agent is an anti-inflammatory agent.

4. The microlead of claim 3 wherein the anti-inflammatory agent is a glucocorticoid provided by dexamethasone sodium phosphate.

5. The microlead of claim 2, wherein the anti-inflammatory agent is a non-steroidal anti-inflammatory agent.

6. The microlead of claim 1, wherein the distal end of the microlead comprises an extension of the insulation layer beyond the termination of said cable, said extension defining a cavity forming an additional reservoir for the pharmacologically active agent, the reservoir being closed at its distal end by an atraumatic element.

7. The microlead of claim 1, wherein the diameter of the distal end of the microlead is less than 0.5 mm.

8. The microlead of claim 1, wherein the insulation layer comprises an ethylene tetrafluoroethylene layer.

9. The microlead of claim 1, wherein the insulation layer is less than 40 μ

m.

10. The microlead of claim 1, wherein the interstitial space is approximately 50% of the volume delimited by the inner wall of the insulation layer.

11. A method for the manufacture of a microlead for implantation in venous, arterial or lymphatic networks, the method comprising:

a) obtaining a microlead, the microlead comprising;

an active distal portion formed by an electrically conductive cable formed by a strand of microcables, each microcable formed of a strand of individual metallic wires;

an insulation layer of an electrically insulating material sheathing the cable;

at least one exposed area formed in the insulation layer so as to form a corresponding electrode of the microlead; and

an interstitial space defined by the internal wall of the insulation layer and between the wires of each microcable;

b) immersing the microlead in a bath of a solution of a pharmacologically active agent;

c) placing the microlead and the bath in a sealed chamber and providing a vacuum of the enclosure, so as to evacuate the remaining air in the interstitial space;

d) recovering the pressure, or establishment of an overpressure in the enclosure, so as to induce penetration of the pharmacologically active agent in the interstitial space; and

e) extracting the microlead from the bath and drying the microlead, so as to extract the liquid phase of the solution contained in the interstitial space.

12. The method of claim 11, wherein steps c) and d) are repeated in sequence a plurality of times.

13. The method of claim 11, further comprising a final step of:

f) sterilizing the microlead obtained after step e) by passing through an enclosure filled with ethylene oxide.

14. The method of claim 11, wherein the pharmacologically active agent is dexamethasone sodium phosphate, and the solution is an aqueous solution at a concentration between 0.3 and 5.0 g of dexamethasone per 100 ml of deionized water.

15. A method for providing a pharmacologically active agent to a stimulation area in the venous, arterial or lymphatic network, the method comprising:

providing a microlead, the microlead comprising;

an active distal portion formed by an electrically conductive cable formed by a strand of microcables, each microcable formed of a strand of individual metallic wires;

an insulation layer of an electrically insulating material sheathing the cable;

at least one exposed area formed in the insulation layer so as to form a corresponding electrode of the microlead; and

an interstitial space defined by the internal wall of the insulation layer and between the wires of each microcable;

introducing a pharmacologically active agent to the interstitial space;

implanting the microlead in the venous, arterial, or lymphatic network; and

allowing the pharmacologically active agent to diffuse through the at least one exposed area into the tissue surrounding the exposed area at the stimulation area.

16. The method of claim 15, wherein the pharmacologically active agent is an anti-inflammatory agent.

17. The method of claim 16, wherein the anti-inflammatory agent is a glucocorticoid.

18. The method of claim 17, wherein the glucocorticoid is dexamethasone sodium phosphate.

19. The method of claim 16, wherein the anti-inflammatory agent is a non-steroidal anti-inflammatory agent.

20. The method of claim 16, wherein the introducing comprises:

introducing the pharmacologically active agent in an aqueous solution into the intestinal space; and

allowing the solution to dry so as to allow recrystallization of the pharmacologically active agent into a solid form.