Leadless cardiac pacemaker with delivery and/or retrieval features

1. An implantable leadless cardiac pacing device comprising:

a housing having a proximal end and a distal end;

an electrode positioned proximate the distal end of the housing configured to be positioned adjacent cardiac tissue; and

a docking member extending from the proximal end of the housing along a central longitudinal axis of the housing, the docking member configured to facilitate retrieval of the implantable leadless cardiac pacing device;

the docking member including a head portion centered on the central longitudinal axis and a neck portion centered on the central longitudinal axis, the neck portion extending between the housing and the head portion;

the head portion having a radial dimension measured from the central longitudinal axis to an outer peripheral surface of the head portion and the neck portion having a radial dimension measured from the central longitudinal axis to an outer peripheral surface of the neck portion,

wherein the radial dimension of the neck portion is less than the radial dimension of the head portion;

the head portion including a recess extending into the head portion from a proximal surface of the head portion to a proximally-facing surface formed within the head portion;

wherein the recess opens out to the peripheral surface of the head portion and the proximal surface of the head portion.

2. The implantable leadless cardiac pacing device of claim 1 , further comprising a member extending across the recess.

3. The implantable leadless cardiac pacing device of claim 2 , wherein the member extends generally perpendicular to the recess.

4. The implantable leadless cardiac pacing device of claim 3 , wherein each of the member and the recess extend generally perpendicular to the central longitudinal axis of the housing.

5. The implantable leadless cardiac pacing device of claim 2 , wherein the member divides the recess into a first portion on a first side of the member and a second portion on a second side of the member.

6. The implantable leadless cardiac pacing device of claim 5 , wherein the first portion of the recess opens out to the outer peripheral surface of the head portion on a first side of the head portion and the second portion of the recess opens out to the outer peripheral surface of the head portion on a second side of the head portion opposite the first side of the head portion.

7. The implantable leadless cardiac pacing device of claim 2 , further comprising a tether attached to the member.

8. The implantable leadless cardiac pacing device of claim 1 , wherein the recess extends across the head portion from a first side of the head portion to a second side of the head portion.

9. The implantable leadless cardiac pacing device of claim 1 , wherein the head portion is a knob having a first diameter and the neck portion has a second diameter less than the first diameter.

10. The implantable leadless cardiac pacing device of claim 1 , wherein the head portion has a distal surface opposite the proximal surface from which the neck portion extends from, wherein the recess does not extend to the distal surface.

11. An implantable leadless cardiac pacing device comprising:

a housing having a proximal end and a distal end;

an electrode positioned proximate the distal end of the housing configured to be positioned adjacent cardiac tissue; and

a docking member extending from the proximal end of the housing along a longitudinal axis of the housing, the docking member configured to facilitate retrieval of the implantable leadless cardiac pacing device;

the docking member including a head portion and a reduced diameter neck portion extending between the housing and the head portion;

the head portion having a proximal surface and an outer circumferential surface;

the head portion including a recess extending laterally across the head portion from a first location on the outer circumferential surface on a first side of the head portion to a second location on the outer circumferential surface on a second side of the head portion opposite the first side of the head portion relative to the longitudinal axis;

wherein the recess is at least partially defined by a proximally-facing surface formed within the head portion.

12. The implantable leadless cardiac pacing device of claim 11 , further comprising a member extending across the recess.

13. The implantable leadless cardiac pacing device of claim 12 , wherein the member divides the recess into a first portion on a first side of the member and a second portion on a second side of the member.

14. The implantable leadless cardiac pacing device of claim 13 , wherein the head portion includes an aperture below the member, the aperture connecting the first and second portions of the recess.

15. The implantable leadless cardiac pacing device of claim 14 , further comprising a tether attached to the member.

16. The implantable leadless cardiac pacing device of claim 15 , wherein the tether passes through the aperture.

17. The implantable leadless cardiac pacing device of claim 12 , wherein the member is formed as a unitary portion of the docking member.

18. The implantable leadless cardiac pacing device of claim 11 , wherein the member is a pin disposed in a bore of the docking member.

19. The implantable leadless cardiac pacing device of claim 11 , wherein the recess extends into the head portion from the proximal surface.

20. The implantable leadless cardiac pacing device of claim 19 , wherein the head portion has a distal surface opposite the proximal surface from which the neck portion extends from, wherein the recess does not extend to the distal surface.