Pacemaker retrieval systems and methods

1. A catheter system, comprising:

a catheter shaft extending along a longitudinal axis to a distal end;

a docking cap having an interior configured to receive a medical device;

a bearing between the distal end of the catheter shaft and the docking cap to allow the docking cap to rotate relative to the catheter shaft, wherein the bearing includes a plurality of balls between the docking cap and the catheter shaft; and

a torque shaft disposed within the catheter shaft and coupled to the docking cap, wherein the torque shaft is rotatable about the longitudinal axis to apply rotational torque to the docking cap such that the docking cap rotates on the bearing relative to the catheter shaft.

2. The catheter system of claim 1 further comprising a handle coupled to the catheter shaft and the torque shaft, wherein the handle is operably configured to move the torque shaft along the longitudinal axis relative to the catheter shaft to connect the torque shaft to the docking cap, and wherein the handle is operably configured to rotate the torque shaft relative to the catheter shaft to apply the rotational torque to the docking cap when the torque shaft is connected to the docking cap.

3. The catheter system of claim 1 , wherein the torque shaft extends through the docking cap into the interior.

4. The catheter system of claim 3 further comprising a slot in the docking cap and a key on the torque shaft, the slot configured to engage the key, wherein rotation of the torque shaft about the longitudinal axis when the key is engaged with the slot transmits rotational torque from the key to the slot.

5. The catheter system of claim 1 further comprising a snare disposed within the catheter shaft and extendable distally beyond the distal end of the catheter shaft, wherein the snare includes one or more loops offset from the longitudinal axis of the catheter shaft when the snare is advanced distally beyond the distal end of the catheter shaft.

6. The catheter system of claim 5 , wherein the one or more loops include a plurality of loops.

7. A leadless cardiac pacemaker system, comprising:

a leadless cardiac pacemaker including a retrieval feature; and

a catheter system comprising:

a catheter shaft extending along a longitudinal axis to a distal end,

a docking cap having an interior configured to receive the retrieval feature of the leadless cardiac pacemaker,

a bearing between the distal end of the catheter shaft and the docking cap to allow the docking cap to rotate relative to the catheter shaft, wherein the bearing includes a plurality of balls between the docking cap and the catheter shaft, and

a torque shaft disposed within the catheter shaft and coupled to the docking cap, wherein the torque shaft is rotatable about the longitudinal axis to apply rotational torque to the docking cap such that the docking cap rotates on the bearing relative to the catheter shaft.

8. The leadless cardiac pacemaker system of claim 7 further comprising a handle coupled to the catheter shaft and the torque shaft, wherein the handle is operably configured to move the torque shaft along the longitudinal axis relative to the catheter shaft to connect the torque shaft to the docking cap, and wherein the handle is operably configured to rotate the torque shaft relative to the catheter shaft to apply the rotational torque to the docking cap when the torque shaft is connected to the docking cap.

9. The leadless cardiac pacemaker system of claim 7 , wherein the torque shaft extends through the docking cap into the interior.

10. The leadless cardiac pacemaker system of claim 9 further comprising a slot in the docking cap and a key on the torque shaft, the slot configured to engage the key, wherein rotation of the torque shaft about the longitudinal axis when the key is engaged with the slot transmits rotational torque from the key to the slot.

11. The leadless cardiac pacemaker system of claim 7 further comprising a snare disposed within the catheter shaft and extendable distally beyond the distal end of the catheter shaft, wherein the snare includes one or more loops offset from the longitudinal axis of the catheter shaft when the snare is advanced distally beyond the distal end of the catheter shaft.

12. The leadless cardiac pacemaker system of claim 11 , wherein the one or more loops include a plurality of loops.

13. A method of retrieving a medical device from a patient, comprising:

grasping a retrieval feature of a medical device with a snare;

pulling the snare to position the retrieval feature of the medical device inside an interior of a docking cap, wherein the docking cap is rotatably coupled to a catheter shaft by a bearing, and wherein the bearing includes a plurality of balls between the docking cap and the catheter shaft; and

rotating, about a longitudinal axis of the catheter shaft, a torque shaft coupled to the docking cap to apply a rotational torque to the docking cap such that the docking cap rotates on the bearing relative to the catheter shaft.

14. The method of claim 13 , wherein the medical device comprises a leadless cardiac pacemaker.

15. The method of claim 13 further comprising moving the torque shaft along the longitudinal axis of the catheter shaft to connect the torque shaft to the docking cap, wherein moving the torque shaft along the longitudinal axis includes pulling the torque shaft to engage a key of the torque shaft with a slot of the docking cap.

16. The method of claim 13 , wherein grasping the retrieval feature includes grasping the retrieval feature with one or more loops of the snare.

17. The method of claim 16 further comprising advancing a snare sleeve distally over the snare to collapse the one or more loops of the snare on the retrieval feature.

18. The method of claim 13 further comprising

covering the medical device with a protective sheath; and

removing the device from a patient.