CARDIAC PACING/SENSING LEAD PROVIDING FAR-FIELD SIGNAL REJECTION

• US 20080046060A1
• Filed: 10/23/2007
• Published: 02/21/2008
• Est. Priority Date: 04/21/2005
• Status: Abandoned Application

• Current Assignee: Pacesetter Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Pacesetter Incorporated (Abbott Laboratories Incorporated)
• Inventors: Kroll, Mark, Helland, John
• Application Number:
  US11/877,082
• Publication Number:
  US 20080046060A1
• Time in Patent Office: Days
• US Class Current: 607/122
• CPC Class Codes: A61N 1/056 Transvascular endocardial electrode systems
• CPC Class Codes: A61N 1/0573 chacterised by means penetrating the heart tissue, e.g. helix needle or hook
• CPC Class Codes: A61N 1/3702 Physiological parameters A61N1/365 takes precedence; evoked response A61N1/371
• CPC Class Codes: A61N 1/3704 Circuits specially adapted therefor, e.g. for sensitivity control

Abstract

A proximal end of a lead body carries a connector assembly. A first electrical conductor within the lead body electrically connects a tip electrode to a first electrical contact on the connector assembly. A collar electrode is carried by a distal end portion of the lead body. A second electrical conductor within the lead body electrically connects the collar electrode to a second electrical contact on the connector assembly. A ring electrode, carried by the distal end portion of the lead body, is disposed proximally of the collar electrode in spaced-apart relationship thereto and is connected through a switching device to a node point along the second conductor. The switching device has a first state permitting an electrical current to be conducted between the ring electrode and the node point and a second state in which the ring electrode is electrically isolated from the node point. Preferably, the switching device comprises a diode.

Claims

1. A cardiac lead for transmitting electrical pacing and sensing signals between an electrical medical device and selected cardiac tissue, the lead comprising:

a lead body having a proximal end, a distal tip and a distal end portion extending proximally from the distal tip, the proximal end of the lead body carrying a connector assembly electrically connectable to the electrical medical device;

a helical screw-in pacing/sensing electrode extendable and retractable relative to the distal tip of the lead body;

a first electrical conductor within the lead body electrically connecting the helical screw-in pacing/sensing electrode to a first electrical contact on the connector assembly;

a collar pacing/sensing electrode carried by the distal end portion of the lead body at the distal tip thereof;

a second electrical conductor within the lead body electrically connecting the collar pacing/sensing electrode to a second electrical contact on the connector assembly;

a ring pacing/sensing electrode carried by the distal end portion of the lead body, the ring pacing/sensing electrode being disposed proximally of the collar pacing/sensing electrode in spaced-apart relationship thereto, the ring pacing/sensing electrode being connected through a switching device to a node point along the second electrical conductor to electrically separate a pacing dipole from a sensing dipole; and

a resistor connected between the node point and the collar pacing/sensing electrode;

wherein pacing is performed between the helical pacing/sensing electrode and the ring pacing/sensing electrode, wherein a pacing signal is applied to the first electrical conductor and hence to the helical pacing/sensing electrode and a return pacing signal flows through the switching device from the ring pacing/sensing electrode and to the second conductor, and wherein the resistor assures that no significant return pacing current is drawn through the collar pacing/sensing electrode; and

wherein sensing is performed between the helical pacing/sensing electrode and the collar pacing/sensing electrode, wherein during sensing the sensing signal passes the resistor from the collar pacing/sensing electrode and to the second electrical conductor, and wherein during sensing the switching device blocks the sensing signal from the ring pacing/sensing electrode.

2. The lead of claim 1 in which:

the helical screw-in pacing/sensing electrode and the collar pacing/sensing electrode comprise a sensing dipole.

3. The lead of claim 1 in which:

the helical screw-in pacing/sensing electrode and the ring pacing/sensing electrode comprise a pacing dipole.

4. The lead of claim 1 in which:

the switching device comprises a diode.

5. The lead of claim 4 in which:

the diode is a small form factor, low forward voltage drop diode.

6. The lead of claim 4 in which:

the diode comprises an anode electrically connected to the node point and a cathode electrically connected to the ring pacing/sensing electrode.

7. The lead of claim 1 in which:

the lead body carries a shocking electrode positioned proximally of the ring pacing/sensing electrode, the shocking electrode being adapted to be electrically connected to a separate contact on the connector assembly.

8. A cardiac lead for transmitting electrical pacing and sensing signals between an electrical medical device and selected cardiac tissue, the lead comprising:

a lead body having a proximal end, a distal tip and a distal end portion extending proximally from the distal tip, the proximal end of the lead body carrying a connector assembly electrically connectable to the electrical medical device;

a helical screw-in pacing/sensing electrode extendable and retractable relative to the distal tip of the lead body;

a first electrical conductor within the lead body electrically connecting the helical screw-in pacing/sensing electrode to a first electrical contact on the connector assembly;

a collar pacing/sensing electrode carried by the distal end portion of the lead body at the distal tip thereof;

a second electrical conductor within the lead body electrically connecting the collar pacing/sensing electrode to a second electrical contact on the connector assembly;

a ring pacing/sensing electrode carried by the distal end portion of the lead body, the ring pacing/sensing electrode being disposed proximally of the collar pacing/sensing electrode in spaced-apart relationship thereto, the ring pacing/sensing electrode being connected through a switching device to a node point along the second conductor, the switching device having a first state permitting an electrical current to be conducted between the ring pacing/sensing electrode and the node point and a second state in which the ring pacing/sensing electrode is electrically isolated from the node point; and

an electrical resistor disposed between the collar pacing/sensing electrode and the node point.

9. The lead of claim 8 in which:

the helical screw-in pacing/sensing electrode and the collar pacing/sensing electrode comprise a sensing dipole.

10. The lead of claim 8 in which:

the helical screw-in pacing/sensing electrode and the ring pacing/sensing electrode comprise a pacing dipole.

11. The lead of claim 8 in which:

the switching device comprises a diode.

12. The lead of claim 11 in which:

the diode is a small form factor, low forward voltage drop diode.

13. A cardiac lead for transmitting electrical pacing and sensing signals between an electrical medical device and selected cardiac tissue, the lead comprising:

a lead body having a proximal end, a distal tip and a distal end portion extending proximally from the distal tip, the proximal end of the lead body carrying a connector assembly electrically connectable to the electrical medical device;

a first pacing/sensing electrode at the distal tip of the lead body;

a first electrical conductor within the lead body electrically connecting the first pacing/sensing electrode to a first electrical contact on the connector assembly;

a second pacing/sensing electrode carried by the distal end portion of the lead body at the distal tip thereof;

a second electrical conductor within the lead body electrically connecting the second electrode to a second electrical contact on the connector assembly;

a third pacing/sensing electrode carried by the distal end portion of the lead body, the third pacing/sensing electrode being disposed proximally of the second electrode in spaced-apart relationship thereto, and a switching device connecting the third electrode to a node point along the second conductor, the switching device having a first state permitting an electrical current to be conducted between the third electrode and the node point and a second state in which the third electrode is electrically isolated from the node point; and

an electrical resistor disposed between the collar electrode and the node point.

14. The lead of claim 13 in which:

the switching device comprises a diode.

15. The lead of claim 13 in which:

the diode comprises an anode electrically connected to the node point and a cathode electrically connected to the third pacing/sensing electrode.

16. The lead of claim 13 in which:

the lead body carries a shocking electrode positioned proximally of the third pacing/sensing electrode, the shocking electrode being adapted to be electrically connected to a separate contact on the connector assembly.

17. The lead of claim 13 in which:

the first sensing/pacing electrode and the second pacing/sensing electrode comprise a sensing dipole.

18. The lead of claim 13 in which:

the first pacing/sensing electrode and the third pacing/sensing electrode comprise a pacing dipole.

19. The lead of claim 13 in which:

the interelectrode spacing between a distal extremity of the third pacing/sensing electrode and a proximal extremity of the second pacing/sensing electrode ranges from 5 to 30 mm.

20. The lead of claim 13 in which:

the first pacing/sensing electrode is a helical screw-in electrode, the second pacing/sensing electrode is a collar electrode, and the third pacing/sensing electrode is a ring electrode.