Implantable medical device for atrial deployment

1. A leadless cardiac pacemaker (LCP), the LCP comprising:

a power source;

circuitry operatively coupled to the power source, the circuitry configured to pace a patient's heart and/or sense electrical activity of the patient's heart;

a housing at least partially enclosing the circuitry and configured to be positioned within an atrium of the patient's heart;

an anode electrode operatively coupled to the circuitry;

a cathode electrode operatively coupled to the circuitry, the cathode electrode spaced from the anode electrode; and

an expandable anchoring member secured relative to the housing, the expandable anchoring member having a plurality of struts connected to a central hub at a first end and extend out to an open second end and having a collapsed configuration for delivery and an expanded configuration for securing the expandable anchoring member and the housing within the atrium of the patient's heart, with the cathode electrode in engagement with an atrium wall of the patient's heart; and

a mesh contacting two or more of the plurality of struts of the expandable anchoring member and extending from the first end toward the second end, wherein the mesh is configured to encourage endotheliazation over at least part of the expandable anchoring member.

2. The LCP of claim 1 , wherein the expandable anchoring member is configured to engage an atrial appendage of the patient's heart in the expanded configuration.

3. The LCP of claim 1 , wherein the housing is secured to the central hub.

4. The LCP of claim 1 , wherein in the collapsed configuration the plurality of struts of the expandable anchoring member extend substantially parallel to a central axis from the first end to the second end, and wherein in the expanded configuration the plurality of struts extend toward the central axis to the central hub at the first end and out further from the central axis at the second end.

5. The LCP of claim 4 , wherein the plurality of struts are biased to expand away from the central axis at the second end when transitioning from the collapsed configuration to the expanded configuration.

6. The LCP of claim 4 , further comprising a plurality of fixation features extending from one or more of the plurality of struts facing away from the central axis for engaging the patient's heart and to help secure the expandable anchoring member and the housing to the patient's heart.

7. The LCP of claim 6 , wherein the plurality of fixation features are configured to engage an atrial appendage of the patient's heart as the plurality of struts radially expand from the central axis at the second end of the expandable anchoring member.

8. The LCP of claim 7 , wherein the plurality of struts are biased to keep the plurality of fixation features engaged with the patient's heart when the expandable anchoring member is in the expanded configuration.

9. The LCP of claim 1 , wherein the housing is removably secured to the expandable anchoring member.

10. The LCP of claim 1 , wherein the power source is removably coupled relative to the housing, and is removable relative to the housing while the housing remains secured to the expandable anchoring member.

11. The LCP of claim 1 , wherein the expandable anchoring member comprises the cathode electrode and further comprises an interconnect for providing a connection to the cathode electrode, and wherein the circuitry is operatively coupled to the interconnect and thus the cathode electrode.

12. The LCP of claim 11 , wherein the cathode electrode is part of or supported by at least one of the plurality of struts.

13. The LCP of claim 1 , wherein the expandable anchoring member comprises a plurality of circumferentially spaced electrodes configured to engage the atrium of the patient's heart, wherein the plurality of circumferentially spaced electrodes are operatively coupled to the circuitry.

14. The LCP of claim 13 , wherein the circuitry is configured to utilize one or more of the circumferentially spaced electrodes for sensing electrical signals of the patient's heart and/or to utilize one or more of the circumferentially spaced electrodes for pacing the patient's heart.

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

a power source;

circuitry operatively coupled to the power source, the circuitry configured to pace a patient's heart and/or sense electrical activity of the patient's heart;

a housing at least partially enclosing the circuitry and configured to be positioned within an atrium of the patient's heart;

an anode electrode operatively coupled to the circuitry;

a cathode electrode operatively coupled to the circuitry, the cathode electrode spaced from the anode electrode;

an expandable anchoring member secured relative to the housing, the expandable anchoring member having a collapsed configuration for delivery and an expanded configuration for engaging an atrial wall of the patient's heart to secure the housing within the atrium of the patient's heart;

wherein the expandable anchoring member extends from a first end to an open second end, wherein the open second end is configured to face the atrial wall, the expandable anchoring member further includes a plurality of struts connected to a central hub at the first end and extend out to the open second end; and

a mesh contacting two or more of the plurality of struts of the expandable anchoring member and extending from the first end toward the second end, wherein the mesh is configured to encourage endotheliazation over at least part of the expandable anchoring member.

16. The IMD of claim 15 , wherein the housing is secured to the central hub.

17. The IMD of claim 16 , wherein at least part of the housing is releasably fixed to the expandable anchoring member.

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

a housing configured to be positioned within an atrium of a patient's heart;

an anode electrode fixed relative to the housing;

a cathode electrode fixed relative to the housing, the cathode electrode spaced from the anode electrode;

an expandable anchoring member secured relative to the housing, the expandable anchoring member having a collapsed configuration for delivery and an expanded configuration for securing the expandable anchoring member and the housing within the atrium of the patient's heart;

the expandable anchoring member comprises four or more struts that, in the expanded configuration, assume an open ended cup shape; and

a mesh contacting a plurality of the four or more struts of the expandable anchoring member and extending from the first end toward the second end, wherein the mesh is configured to encourage endotheliazation over at least part of the expandable anchoring member.