SYSTEM AND METHODS FOR CHRONIC FIXATION OF MEDICAL DEVICES

• US 20150025612A1
• Filed: 07/21/2014
• Published: 01/22/2015
• Est. Priority Date: 07/22/2013
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Haasl, Benjamin J., Schmidt, Brian L., Foster, Arthur J.
• Granted Patent: US 9,333,342 B2
• Time in Patent Office: Days
• US Class Current: 607/127
• 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
• CPC Class Codes: A61N 1/059 Anchoring means

Abstract

Devices or methods such as for stimulating excitable tissue or sensing physiologic response or other signals that can use chronic fixation mechanism are described. An implantable apparatus can comprise an electrostimulation electrode assembly that can include a primary fixation member and a secondary fixation member. The primary fixation member can be actively engaged or affixed to a target tissue of a patient, and the second fixation member can be biased against the target tissue, collapsed or compressed against the target tissue when the primary fixation member is affixed to the target tissue. The electrostimulation electrode assembly can also include at least one electrode such as to contact heart or other excitable tissue such as to deliver chronic electrostimulation or sensing physiologic responses.

Claims

1. An implantable apparatus comprising:

an electrostimulation electrode assembly including;

a primary fixation member that is sized, shaped, or otherwise configured to be actively engaged or affixed to a target tissue of a patient;

a secondary fixation member that is sized, shaped, or otherwise configured to bias against the target tissue when the primary fixation member is engaged or affixed to the target tissue; and

an electrostimulation electrode body, including at least one electrode, that is sized, shaped, or otherwise configured to be attached to the primary fixation member and the secondary fixation member, and to deliver electrostimulation to a stimulation site of the patient via the at least one electrode.

2. The apparatus of claim 1, wherein the secondary fixation member is compressible and configured to be collapsed or compressed against the target tissue when the primary fixation member is engaged with or affixed to the target tissue.

3. The apparatus of claim 1, wherein:

the primary fixation member includes a first rotationally-oriented element;

the secondary fixation member includes a second rotationally-oriented element; and

the primary and secondary rotationally-oriented elements are coaxial.

4. The apparatus of claim 3, wherein the first rotationally-oriented element includes a screw-in helix first coil with at least one of a first handedness or a first pitch, and the second rotationally-oriented element includes a second coil with at least one of a second handedness or a second pitch, the at least one of the first handedness or the first pitch being non-identical to the respective the at least one of the second handedness or the second pitch.

5. The apparatus of claim 3, wherein the first rotationally-oriented element extends farther from the electrostimulation electrode body than the second rotationally-oriented element.

6. The apparatus of claim 1, wherein the primary fixation member is stiffer than the secondary fixation member.

7. The apparatus of claim 1, wherein at least a portion of the secondary fixation member is a polymer.

8. The apparatus of claim 1, wherein the secondary fixation member includes radiopaque material such that the secondary fixation member is capable of providing a radiopaque reading of a degree of fixation of the electrostimulation electrode assembly.

9. The apparatus of claim 1, wherein the electrostimulation electrode body comprises an elongated wire extending between a distal end and a proximal end, the proximal end being configured to be coupled to a separate electrostimulation generator configured to generate electrostimulation to be delivered to the stimulation site.

10. The apparatus of claim 1, wherein the electrostimulation electrode body comprises a housing that includes an electrostimulation generation circuit configured to generate and deliver electrostimulation to the stimulation site.

11. The apparatus of claim 10, wherein the electrostimulation generation circuit is configured to be electrically coupled to at least one of the primary fixation member or the secondary fixation member, the at least one of the primary fixation member or the secondary fixation member configured to provide an electrode for delivering chronic electrostimulation to the target tissue.

12. An implantable medical device (IMD), comprising:

a primary fixation member that is sized, shaped, or otherwise configured to be actively engaged or affixed to a heart;

a secondary fixation member that is sized, shaped, or otherwise configured to be collapsed and compressed to bias against, and without being actively engaged or affixed to, the heart when the primary fixation member is engaged or affixed to the heart; and

an electrostimulation unit that is sized, shaped, or otherwise configured to be attached to the primary fixation member and the secondary fixation member, and that includes at least one electrode to deliver electrostimulation to a stimulation site of the heart when at least one of the primary or the secondary fixation member is engaged with the heart.

13. The device of claim 12, wherein the electrostimulation unit comprises an elongated wire extending between a distal end and a proximal end, the proximal end configured to be coupled to an electrostimulation generator, and the distal end configured to be attached to the at least one of the primary and the secondary fixation members.

14. The device of claim 12, wherein the electrostimulation unit comprises a housing including a stimulation circuit configured to generate and deliver an electrostimulation to the stimulation site of the heart through the at least one of the primary or the secondary fixation member.

15. A method comprising:

providing an implantable medical device (IMD) configured to deliver an electrostimulation to a stimulation site of a patient;

providing the IMD to be engaged or affixed to a target tissue, including;

providing a primary fixation member configured to be actively engaged or affixed to the target tissue; and

providing a secondary fixation member configured to be collapsed or compressed against the tissue when the primary fixation member is engaged or affixed to the target tissue; and

delivering the electrostimulation to the target tissue via at least one electrode.

16. The method of claim 15, wherein providing the primary fixation member includes rotating the primary fixation member to engage a rotationally-oriented element to the target tissue.

17. The method of claim 15, wherein providing the IMD to be engaged or affixed to the target tissue includes determining a degree of fixation of the IMD when at least one of the primary or the secondary fixation member is engaged or affixed to the target tissue.

18. The method of claim 17, wherein determining the degree of fixation includes:

generating a first radiopaque reading of the secondary fixation member before being collapsed or compressed against the target tissue;

generating a second radiopaque reading of the secondary fixation member after being collapsed or compressed against the target tissue; and

determining a degree of deformation of the secondary fixation member using a comparison between the first radiopaque reading and the second radiopaque reading.

19. The method of claim 15, wherein:

providing the IMD includes providing an implantable lead to be engaged or affixed to the target tissue, the implantable lead including a proximal end configured to be coupled to an electrostimulator device and a distal end configured to be attached to the primary fixation member and the secondary fixation member, and

delivering the electrostimulation includes configuring the electrostimulator device for delivering electrostimulation via the implantable lead to an electrostimulation electrode secured using at least one of the primary or the secondary fixation member.

20. The method of claim 15, wherein:

providing the IMD includes providing an untethered electrostimulator device to be engaged or affixed to the target tissue, the untethered electrostimulator including a housing configured to be attached to the primary fixation member and the secondary fixation member, and

delivering the electrostimulation includes configuring the untethered electrostimulator for delivering an electrostimulation to an electrostimulation electrode secured using at least one of the primary or the secondary fixation member.