Pacemaker retrieval systems and methods
A catheter system for retrieving a leadless cardiac pacemaker from a patient is provided. The cardiac pacemaker can include a docking or retrieval feature configured to be grasped by the catheter system. In some embodiments, the retrieval catheter can include a snare configured to engage the retrieval feature of the pacemaker. The retrieval catheter can include a torque shaft selectively connectable to a docking cap and be configured to apply rotational torque to a pacemaker to be retrieved. Methods of delivering the leadless cardiac pacemaker with the delivery system are also provided.
1. A catheter for retrieving a medical device from a patient, comprising:
a catheter shaft;
a snare disposed within the catheter shaft and extendable distally beyond the catheter shaft;
a docking cap disposed on a distal portion of the catheter shaft, the docking cap being rotatable independent of the catheter shaft, wherein the docking cap includes an interior configured to receive the medical device;
a torque shaft disposed within the catheter shaft and extending through the docking cap into the interiors; and
a handle coupled to the catheter shaft and the torque shaft, wherein the handle is operably configured to move the torque shaft proximally 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 rotational torque to the docking cap when the torque shaft is connected to the docking cap.
2. The catheter of claim 1 further comprising an interference feature disposed on an interior surface of the docking cap, the interference feature configured to engage a corresponding interference feature on the medical device to be retrieved.
3. The catheter of claim 2 , wherein the interference feature disposed on the interior surface of the docking cap comprises a ridge.
4. The catheter of claim 1 further comprising a slot disposed inside the docking cap, the slot configured to engage a key on the torque shaft.
5. The catheter of claim 4 , wherein the torque shaft is configured to apply rotational torque to the docking cap when the docking cap slot is engaged with the key on the torque shaft.
6. The catheter of claim 5 , wherein a proximal portion of the torque shaft is coupled to a control knob on the handle.
7. The catheter of claim 6 , wherein longitudinal movement of the control knob along the handle causes the torque shaft to engage or disengage the slot in the docking cap.
8. The catheter of claim 6 , wherein rotation of the control knob causes the torque shaft and the docking cap to rotate when the key on the torque shaft is engaged with the docking cap slot.
9. The catheter of claim 6 , wherein longitudinal movement of the control knob along the handle moves the torque shaft and the snare longitudinally.
10. The catheter of claim 1 , wherein the snare comprises a plurality of loops.
11. The catheter of claim 1 , wherein the snare comprises a single loop.
12. The catheter of claim 11 , wherein the single loop comprises a loop perpendicular to the catheter shaft.
13. The catheter of claim 1 , wherein the snare is offset from a longitudinal axis of the catheter when the snare is advanced distally beyond the catheter shaft.
14. A leadless pacemaker and retrieval system, comprising:
a leadless cardiac pacemaker having a retrieval feature coupled to the pacemaker with at least one flexible stem; and
a delivery catheter comprising:
a catheter shaft,
a snare disposed within the catheter shaft and extendable distally beyond the catheter shaft,
a docking cap disposed on a distal portion of the catheter shaft, the docking cap being rotatable independent of the catheter shaft, wherein the docking cap includes an interior sized and configured to receive the retrieval feature of the leadless cardiac pacemaker,
a torque shaft disposed within the catheter shaft and extending through the docking cap into the interior, and
a handle coupled to the catheter shaft and the torque shaft, wherein the handle is operably configured to move the torque shaft proximally relative to the catheter shaft to connect the torque shaft to the docking cap, wherein the handle is operably configured to rotate the torque shaft relative to the catheter shaft to apply rotational torque to the docking cap and the leadless cardiac pacemaker when the torque shaft is connected to the docking cap and the retrieval feature is disposed in the interior.
15. The catheter of claim 14 further comprising an interference feature disposed on an interior surface of the docking cap, the interference feature configured to engage a corresponding interference feature on the pacemaker.
16. The catheter of claim 14 further comprising a slot disposed inside the docking cap, the slot configured to engage a key on the torque shaft.
17. The catheter of claim 16 , wherein the torque shaft is configured to apply rotational torque to the docking cap when the docking cap slot is engaged with the key on the torque shaft.
18. The catheter of claim 17 , wherein a proximal portion of the torque shaft is coupled to a control knob on the handle.
19. The catheter of claim 18 , wherein longitudinal movement of the control knob along the handle causes the torque shaft to engage or disengage the slot in the docking cap.
20. The catheter of claim 18 , wherein rotation of the control knob causes the torque shaft and the docking cap to rotate when the key on the torque shaft is engaged with the docking cap slot.
21. The catheter of claim 18 , wherein longitudinal movement of the control knob along the handle moves the torque shaft and the snare longitudinally.
22. The catheter of claim 14 , wherein the snare comprises a plurality of loops.
23. The catheter of claim 14 , wherein the snare comprises a single loop.
24. The catheter of claim 14 , wherein the snare is offset from a longitudinal axis of the catheter when the snare is advanced distally beyond the catheter shaft.
25. A method of retrieving a medical device from a patient, comprising:
positioning a snare of a catheter in proximity to a retrieval feature of the medical device and distal to a docking cap rotatably coupled to a catheter shaft of the catheter;
grasping the retrieval feature of the medical device with the snare;
pulling the snare proximally into the catheter to position the retrieval feature of the medical device inside an interior of the docking cap of the catheter;
pulling a torque shaft to connect the torque shaft to the docking cap, wherein the torque shaft is disposed within the catheter shaft and extends through the docking cap into the interior; and
rotating the torque shaft independently of the catheter shaft to apply a rotational torque to the docking cap, thereby applying rotational torque from the docking cap to the medical device to unscrew the medical device from tissue in the patient.
26. The method of claim 25 , wherein the medical device comprises a leadless cardiac pacemaker.
27. The method of claim 25 , wherein pulling the torque shaft comprises engaging a key feature on the torque shaft with a matching slot in the docking cap.
28. The method of claim 25 further comprising
covering the medical device with a protective sheath; and
removing the device from the patient.
29. The method of claim 25 , wherein grasping the retrieval feature comprises grasping the retrieval feature with a loop of the snare.
30. The method of claim 25 , wherein grasping the retrieval feature comprises advancing a snare sleeve distally over the snare to collapse the snare.