IMPLANTABLE MEDICAL DEVICE FIXATION

• US 20120172892A1
• Filed: 04/28/2011
• Published: 07/05/2012
• Est. Priority Date: 12/29/2010
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Grubac, Vladimir, Bonner, Matthew D., Usher, Raymond W., Anderson, Thomas A., Alfoqaha, Arshad A.
• Granted Patent: US 9,775,982 B2
• Time in Patent Office: Days
• US Class Current: 606/129
• 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 1/0573 chacterised by means penetrating the heart tissue, e.g. helix needle or hook
• CPC Class Codes: A61N 1/37518 Anchoring of the implants, e.g. fixation
• CPC Class Codes: A61N 1/3756 Casings with electrodes thereon, e.g. leadless stimulators

Abstract

Various fixation techniques for implantable medical device (IMDs) are described. In one example, an assembly comprises an IMD; and a set of active fixation tines attached to the IMD. The active fixation tines in the set are deployable from a spring-loaded position in which distal ends of the active fixation tines point away from the IMD to a hooked position in which the active fixation tines bend back towards the IMD. The active fixation tines are configured to secure the IMD to a patient tissue when deployed while the distal ends of the active fixation tines are positioned adjacent to the patient tissue.

Claims

1. An assembly comprising:

an implantable medical device; and

a set of active fixation tines attached to the implantable medical device,

wherein the active fixation tines in the set are deployable from a spring-loaded position in which distal ends of the active fixation tines point away from the implantable medical device to a hooked position in which the active fixation tines bend back towards the implantable medical device,

wherein the active fixation tines are configured to secure the implantable medical device to a patient tissue when deployed while the distal ends of the active fixation tines are positioned adjacent to the patient tissue.

2. The assembly of claim 1, wherein deploying the active fixation tines from the spring-loaded position to the hooked position comprises releasing the active fixation tines in unison from the spring loaded position and allowing the active fixation tines to assume the hooked position.

3. The assembly of claim 1, wherein the active fixation tines are positioned substantially equidistant from each other in a circular arrangement.

4. The assembly of claim 1,

wherein the active fixation tines are in a circular arrangement,

wherein the active fixation tines are oriented outwardly relative to the circular arrangement.

5. The assembly of claim 3, wherein the active fixation tines are configured to create opposing radial forces when deployed in unison such that the active fixation tines pull the implantable medical device towards the patient tissue when the active fixation tines are deployed while the distal ends of the active fixation tines are positioned adjacent to the patient tissue.

6. The assembly of claim 1,

wherein the active fixation tines in the set are positioned in a circular arrangement,

wherein the implantable medical device includes an electrode for at least one of sensing a physiological condition of the patient and delivering a therapy to the patient,

wherein the electrode located within the circular arrangement, wherein the implantable medical device is configured such that the electrode contacts the patient tissue when the implantable medical device is secured to the patient tissue by the set of active fixation tines.

7. The assembly of claim 6, wherein the active fixation tines provide a forward pressure of the electrode on the patient tissue to assure good electrode-tissue contact.

8. The assembly of claim 6, wherein the implantable medical device comprises a leadless pacemaker.

9. The assembly of claim 1, wherein the implantable medical device comprises a medical lead and the set of active fixation tines are attached to the distal end of the medical lead.

10. The assembly of claim 1, wherein at least one of the active fixation tines functions as an electrode of the implantable medical device for at least one of sensing a physiological condition of the patient and delivering a therapy to the patient.

11. The assembly of claim 1, wherein the implantable medical device includes a sensor selected from a group consisting of:

a pressure sensor;

an electrocardiogram sensor;

an oxygen sensor;

an accelerometer;

a glucose sensor;

a potassium sensor; and

a thermometer.

12. The assembly of claim 1,

wherein the set of the active fixation tines is remotely deployable to facilitate securing the implantable medical device to the tissue during an implantation procedure,

wherein, after the set of the active fixation tines is deployed to secure the implantable medical device to a patient tissue, the assembly is configured to facilitate releasing the implantable medical device from the tissue without tearing the tissue by pulling the implantable medical device away from the tissue.

13. The assembly of claim 12, wherein releasing the implantable medical device from the tissue without tearing the tissue by pulling the implantable medical device away from the tissue includes:

first, pulling on the implantable medical device to stretch the tissue until the tissue stiffness matches the tine straightening force;

second, further pulling on the implantable medical device until the tines straighten without tearing the tissue; and

third, continue pulling on the implantable medical device once the tines have straightened sufficiently to remove the tines from the tissue without tearing the tissue.

14. The assembly of claim 12, wherein the assembly is further configured to facilitate the redeployment of the set of the active fixation tines after releasing the implantable medical device from the tissue by pulling the implantable medical device away from the tissue and back into the delivery system.

15. The assembly of claim 1, wherein the active fixation tines include a coating selected from a group consisting of:

a radiopaque coating;

a tissue growth promoter; and

a tissue growth inhibitor.

16. The assembly of claim 1, wherein the set of active fixation tines consists of four active fixation tines.

17. The assembly of claim 1, wherein the set of active fixation tines are formed from a shape memory alloy material.

18. The assembly of claim 17, wherein the shape memory alloy material is Nitinol.

21. The kit of claim 18,

wherein, after the set of the active fixation tines is deployed to secure the implantable medical device to the patient tissue, the active fixation tines are configured to facilitate releasing the implantable medical device from the tissue without tearing the tissue by pulling the implantable medical device away from the tissue using the tether.

19. A kit for implanting an implantable medical device within a patient, the kit comprising:

the implantable medical device;

a set of active fixation tines attached to the implantable medical device,

wherein the active fixation tines in the set are deployable from a spring-loaded position in which distal ends of the active fixation tines point away from the implantable medical device to a hooked position in which the active fixation tines bend back towards the implantable medical device,

wherein the active fixation tines are configured to secure the implantable medical device to a patient tissue when deployed while the distal ends of the active fixation tines are positioned adjacent to the patient tissue;

a catheter forming a lumen sized to receive the implantable medical device and hold the active fixation tines in the spring-loaded position, wherein the lumen includes an aperture that is adjacent to the distal end of the catheter; and

a deployment element configured to initiate deployment of the active fixation tines while the implantable medical device is positioned within the lumen of the catheter,

wherein deployment of the active fixation tines while the implantable medical device is positioned within the lumen of the catheter causes the active fixation tines to pull the implantable medical device out of the lumen via the aperture that is adjacent to the distal end of the catheter.

20. The kit of claim 19, further comprising a tether attached to the implantable medical device, the tether being configured to facilitate pulling the implantable medical device back into the lumen from the proximal end of the catheter after the active fixation tines pull the implantable medical device out of the lumen, wherein pulling the implantable medical device back into the lumen with the tether returns the active fixation tines to the spring-loaded position from the hooked position such that the active fixation tines can be redeployed with the deployment element.

22. The kit of claim 19, wherein the deployment element is configured to be remotely activated by a clinician from a proximal end of the catheter.

23. The kit of claim 19, wherein initiating deployment of the active fixation tines with the deployment element comprises pushing the implantable medical device towards the distal end of the catheter until the distal ends of the active fixation tines extend out of the aperture.

24. The kit of claim 19, wherein the active fixation tines are positioned substantially equidistant from each other in a circular arrangement.

25. The kit of claim 19,

wherein the active fixation tines are in a circular arrangement,

wherein the active fixation tines are oriented outwardly relative to the circular arrangement.

26. The kit of claim 19,

wherein the active fixation tines in the set are positioned in a circular arrangement,

wherein the implantable medical device includes an electrode for at least one of sensing a physiological condition of the patient and delivering a therapy to the patient,

wherein the electrode located within the circular arrangement, wherein the implantable medical device is configured such that the electrode contacts the patient tissue when the implantable medical device is secured to the patient tissue by the set of active fixation tines.

27. The kit of claim 19, wherein the implantable medical device is a leadless pacemaker.

28. The kit of claim 19, wherein the implantable medical device is a medical lead and the set of active fixation tines are attached to the distal end of the medical lead, the kit further comprising an electrical stimulation generator configured to attach to the proximal end of the medical lead.

29. The kit of claim 19, wherein at least one of the active fixation tines functions as an electrode of the implantable medical device for at least one of sensing a physiological condition of the patient and delivering a therapy to the patient.

30. The kit of claim 19, wherein the set of active fixation tines are formed from a shape memory alloy material.

31. A method comprising:

obtaining an assembly comprising an implantable medical device and a set of active fixation tines attached to the implantable medical device;

positioning the distal ends of the active fixation tines adjacent a patient tissue; and

deploying the active fixation tines from a spring-loaded position in which distal ends of the active fixation tines point away from the implantable medical device to a hooked position in which the active fixation tines bend back towards the implantable medical device to secure the implantable medical device to the patient tissue.

32. The method of claim 31, further comprising;

obtaining a catheter forming a lumen sized to receive the implantable medical device and hold the active fixation tines in the spring-loaded position, wherein the lumen includes an aperture that is adjacent to the distal end of the catheter,

wherein the assembly is within the lumen during the positioning of the distal ends of the active fixation tines adjacent the patient tissue; and

obtaining a deployment element configured to initiate deployment of the active fixation tines while the implantable medical device is positioned within the lumen of the catheter,

wherein deploying the active fixation tines from the spring-loaded position comprises remotely activating the deployment element to initiate deployment of the active fixation tines while the implantable medical device is positioned within the lumen of the catheter,

wherein initiating deployment the active fixation tines to pull the implantable medical device out of the lumen via the aperture that is adjacent to the distal end of the catheter and secure the implantable medical device to the patient tissue.

33. The method of claim 32, wherein a clinician operates the deployment element from a position adjacent the proximal end of the catheter to initiate the deployment of the active fixation tines.

34. The method of claim 32, further comprising pulling a tether attached to the implantable medical device to pull the implantable medical device back into the lumen after the active fixation tines have pulled the implantable medical device out of the lumen, wherein pulling the implantable medical device back into the lumen with the tether returns the active fixation tines to the spring-loaded position from the hooked position.

35. The method of claim 34, further comprising, after pulling the tether to pull the implantable medical device back into the lumen, using the deployment element to initiate redeployment of the active fixation tines to again secure the implantable medical device to the patient tissue.

36. The method of claim 35,

wherein the active fixation tines in the set are positioned in a circular arrangement,

wherein the implantable medical device includes an electrode for at least one of sensing a physiological condition of the patient and delivering a therapy to the patient,

wherein the electrode located within the circular arrangement, wherein the implantable medical device is configured such that the electrode contacts the patient tissue when the implantable medical device is secured to the patient tissue by the set of active fixation tines,

the method further comprising, after securing the implantable medical device to the patient tissue and before pulling the tether to pull the implantable medical device back into the lumen, evaluating a performance characteristic of the electrode while the implantable medical device is secured to the patient tissue.

37. The method of claim 34, wherein a clinician operates the tether from a position adjacent the proximal end of the catheter to pull the implantable medical device back into the lumen.

38. The method of claim 31,

wherein the active fixation tines are positioned in a circular arrangement,

wherein the active fixation tines are oriented outwardly relative to the circular arrangement.