Implantable device for the effective elimination of cardiac arrhythmogenic sites

• US 5,551,427 A
• Filed: 02/13/1995
• Issued: 09/03/1996
• Est. Priority Date: 02/13/1995
• Status: Expired due to Term

• Current Assignee: BioCardia, Inc
• Original Assignee: Peter A. Altman
• Inventors: Altman, Peter A.
• Primary Examiner(s): Sykes, Angela D.
• Assistant Examiner(s): Huang, Stephen D.
• Application Number:
  US08/387,257
• Time in Patent Office: 568 Days
• Field of Search: 128/642, 607/120-127, 607/119, 607/131, 607/37, 607/60, 607/1, 607/2
• US Class Current: 600/374
• CPC Class Codes: A61F 2/00 Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents as cosmetic articles, see the relevant subclasses, e.g. wigs, hair pieces, A41G3/00, A41G5/00; artificial nails A45D31/00; dental prostheses A61C13/00; materials for prostheses A61L27/00; artificial hearts A61M60/00; artificial kidneys A61M1/14
• CPC Class Codes: A61N 1/056 Transvascular endocardial electrode systems
• CPC Class Codes: A61N 1/0573 chacterised by means penetrating the heart tissue, e.g. helix needle or hook

Abstract

An implantable devices for the effective elimination of an arrhythmogenic site from the myocardium is presented. By inserting small biocompatible conductors and/or insulators into the heart tissue at the arrhythmogenic site, it is possible to effectively eliminate a portion of the tissue from the electric field and current paths within the heart. The device would act as an alternative to the standard techniques for the removal of tissue from the effective contribution to the hearts electrical action which require the destruction of tissue via energy transfer (RF, microwave, cryogenic, etc.). This device is a significant improvement in the state of the art in that it does not require tissue necrosis.

In one preferred embodiment the device is a non conductive helix that is permanently implanted into the heart wall around the arrhythmogenic site. In variations on the embodiment, the structure is wholly or partially conductive, the structure is used as an implantable substrate for anti arrhythmic, inflammatory, or angiogenic pharmacological agents, and the structure is deliverable by a catheter with a disengaging stylet. In other preferred embodiments that may incorporate the same variations, the device is a straight or curved stake, or a group of such stakes that are inserted simultaneously.

Claims

1. A medical device implantable in a heart, for treating arrhythmogenic sites in the heart, the device comprising:

a electrically inactive structure having an exposed surface and biocompatible at least over the exposed surface, said structure adapted to be chronically implanted into cardiac tissue within a region substantially adjacent to an arrhythmogenic site in a heart, and, when so implanted, altering conduction properties of the cardiac tissue within said region; and

wherein the structure incorporates a coupling means for releasably coupling the structure to a delivery device operable to deliver the structure to the region and implant the structure into the cardiac tissue, said coupling means operable to enable disengagement and removal of the delivery device after the structure is implanted.

2. The device of claim 1 wherein:

said structure is selected from a group consisting of helical bodies, stakes, and cages.

3. The device of claim 1 wherein:

said structure is formed of biocompatible materials selected from the group consisting of polytetrafluoroethylene, expanded polytetrafluoroethylene, polyester, polyurethane, silicon, platinum, iridium, titanium, and MP35N.

4. The device of claim 1 wherein:

said structure, at least over an outermost portion thereof that includes said exposed surface, is constructed of a biocompatible material selected from the group consisting of platinum black, titanium nitride, sintered platinum, roughened platinum, roughened MP35N, and roughened titanium, whereby the effective surface area of the structure is enhanced to augment electrical coupling of the structure and the cardiac tissue.

5. The device of claim 1 further including:

a delivery catheter releasably coupled at a distal end thereof to said structure by said coupling means, adapted for intravascularly delivering the structure into the heart and to said region, and further operable at a proximal end thereof to at least partially embed the structure within said cardiac tissue at said region.

6. The device of claim 1 wherein:

said structure includes means for delivering a predetermined pharmacological agent to said cardiac tissue at said region, for further altering conduction properties of said tissue within said region.

7. The device of claim 6 wherein:

said structure includes a substrate coated with a non-conductive controlled release matrix less rigid than the substrate, with the controlled release matrix being at least partially embedded within said tissue when the structure is so implanted.

8. The device of claim 6 wherein:

said predetermined pharmacological agent is selected from a group consisting of anti-arrhythmic agents, angiogenic growth factors, anti-inflammatory agents, and their combinations.

9. The device of claim 6 wherein:

said structure includes a rigid core material forming a proximal head and a distal tip, and an insulative controlled release matrix covering the rigid core material between the head and the tip, to facilitate use of the structure for electrical mapping of said tissue when the structure is at least partially embedded into the tissue.

10. The device of claim 1 wherein:

said structure includes a hollow core and a plurality of apertures from the hollow core open to the outer surface of the structure, a proximally located head in fluid communication with the hollow core, and a tube coupled to the head for supplying a pharmacological agent to the hollow core via the head.

11. The device of claim 10 wherein:

said structure further includes a non-conductive controlled release matrix forming a coating over said apertures, for delivering said predetermined pharmacological agent to an innermost surface of said controlled release matrix.

12. A method of locally altering electrical activity in cardiac tissue at a selected site in the region of the heart, including:

measuring electrical activity in cardiac tissue, to identify a potential implantation site;

introducing a first electrically inactive and biocompatible implantable device into the region of the heart, and at least partially embedding said first implantable device into cardiac tissue at the site to effect an implantation.

13. The method of claim 12 further including:

after said implantation, performing a plurality of electrical measurements in cardiac tissue proximate the site and, based on results of said electrical measurements, performing at least one of the following sub-steps;

(i) determining that the implantation has successfully altered conduction properties as intended;

(ii) based on a determination that the implantation has not successfully altered conduction properties as intended, removing and repositioning the first implantable device; and

(iii) responsive to determining that the implantation has not successfully altered conduction properties as intended, embedding a second electrically inactive and biocompatible implantable device proximate the first implantable device and proximate said site.

14. The method of claim 13 further including:

after said performing the plurality of electrical measurements and before performing said at least one substep, supplying a pharmacological agent via the first implantable device to cardiac tissue proximate the first implantable device.

15. The method of claim 13 further including:

after said implantation and before said performing the plurality of electrical measurements, supplying a pharmacological agent via the first implantable device to cardiac tissue proximate the first implantable device.

16. The method of claim 12 further including:

after said implantation of the first implantable device, supplying a pharmacological agent via the first implantable device to cardiac tissue proximate the first implantable device.

17. The method of claim 16 wherein:

said supplying of a pharmacological agent comprises delivering the pharmacological agent from a source to the implantable device via a tube coupled to the implantable device.

18. The method of claim 12 wherein:

said introducing the first implantable device comprises releasably attaching the first implantable device to a distal end of a catheter, using the catheter to intravascularly deliver the device to the implantation site, manipulating the catheter at a proximal end thereof to achieve said implantation, decoupling the catheter from the first implantable device and withdrawing the catheter after said implantation.

19. An apparatus for locally modifying electrical action within a heart, comprising:

an implantable electrically inactive device including tissue penetration means and a coupling means; and

a delivery device having a proximal end and a distal end adapted for forming a releasable coupling to said implantable device via the coupling means, adapted for delivering the implantable device to a designated site in a heart and manipulable at said proximal end to implant the implantable device by causing said tissue penetration means to enter tissue; and

further adapted for a decoupling from the implantable device and removal after the implantation, whereby the implantable device remains at the site and modifies electrical action at and proximate the site.

20. The apparatus of claim 19 wherein:

said implantable device comprises a means to deliver pharmacological agents to cardiac tissue at and proximate the site.

21. An apparatus for locally modifying electrical action within a heart, comprising:

a biocompatible, electrically inactive, implantable device including a means for penetrating cardiac tissue to effect an implantation of the implantable device at a designated site in a heart, to modify electrical action in the cardiac tissue at and proximate the site.

22. The apparatus of claim 21 wherein:

the implantable device includes a non-conductive controlled release matrix for supplying a predetermined pharmacological agent to the cardiac tissue.

23. The apparatus of claim 21 wherein:

the implantable device, at least over an outermost portion thereof that includes an exposed surface, is constructed of a biocompatible material selected from the group consisting of platinum black, titanium nitride, sintered platinum, roughened platinum, roughened MP35N and roughened titanium, to enhance the effective surface area of the exposed surface and thereby augment electrical coupling of the implantable device and the cardiac tissue.

24. The apparatus of claim 21 further including:

a drug delivery catheter coupled to the implantable device for delivering a pharmacological agent to the implantable device, and wherein the implantable device includes a hollow core in fluid communication with the drug delivery catheter and open to an exterior of the implantable device to supply the pharmacological agent from the delivery catheter to the cardiac tissue.

25. The apparatus of claim 21 further including:

a delivery catheter including a catheter distal end region coupled to the implantable device, said delivery catheter operable at a proximal end thereof to effect said implantation; and

an electrode means at the catheter distal end for sensing electrical action in the cardiac tissue before said implantation, to facilitate locating the site.

26. The apparatus of claim 25 wherein:

the catheter is releasably coupled to the implantable device to allow a decoupling and withdrawal of the delivery catheter after said implantation.