System having a surrogate defibrillation electrode for testing implantable cardioverter-defibrillators during implant

• US 5,772,690 A
• Filed: 10/24/1996
• Issued: 06/30/1998
• Est. Priority Date: 10/24/1996
• Status: Expired due to Fees

• Current Assignee: Pacesetter Incorporated (Abbott Laboratories)
• Original Assignee: Pacesetter Incorporated (Abbott Laboratories)
• Inventors: Kroll, Mark W.
• Primary Examiner(s): Getzow, Scott M.
• Application Number:
  US08/738,953
• Time in Patent Office: 614 Days
• Field of Search: 607/5, 607/7, 607/8, 607/4, 607/142
• US Class Current: 607/7
• CPC Class Codes: A61N 1/3918 characterised by shock pathway, e.g. by electrode configuration
• CPC Class Codes: A61N 1/3943 for threshold determination

Abstract

An external surrogate defibrillation electrode is provided that increases the safety of performing implantation testing of implantable cardioverter-defibrillators. The surrogate electrode has an electrode pad that is attached to the patient'"'"'s skin. If the implantable cardioverter-defibrillator is not capable of providing a sufficiently high-energy defibrillation shock during the implantation procedure, the surrogate electrode attached to the patient'"'"'s skin can be electrically connected to the implantable cardioverter-defibrillator, thereby allowing the implantable cardioverter-defibrillator to effectively apply a rescue shock to the patient.

Claims

1. A system for testing implantable cardioverter-defibrillators during implant, the system having an implantable cardioverter-defibrillator means for applying rescue cardioversion-defibrillation shocks to the heart of a patient in conjunction with implantation of the implantable cardioverter-defibrillator means, the system comprising:

first electrode means for implant in the heart;

second electrode means for positioning adjacent said heart;

the cardioverter-defibrillator means including;

circuitry means connected to the first electrode means and the second electrode means, the circuitry means for applying cardioversion-defibrillation shocks to the heart between the first electrode means and the second electrode means for determining the defibrillation threshold of the heart during implantation of the implantable cardioverter-defibrillator means;

removable external surrogate electrode means for temporary attachment to the skin of the patient and for detachable connection to the implantable cardioverter-defibrillator means in parallel with the second electrode means during implantation of the implantable cardioverter-defibrillator means; and

switch means for electrically connecting the external surrogate electrode means to the implantable cardioverter-defibrillator means for applying a rescue shock from the implantable cardioverter-defibrillator means between the external surrogate electrode means attached to the skin of the patient and the first electrode means during implantation of the implantable cardioverter-defibrillator means wherein the external surrogate electrode means and the switch means include means for detaching the external surrogate electrode means and the switch means from the implantable cardioverter-defibrillator means.

2. The system of claim 1, wherein the first electrode means is a coil electrode.

3. The system of claim 1, wherein the external surrogate electrode means comprises a conductive gel adhesive pad.

4. The system of claim 1, wherein the second electrode is an implantable cardiac device can and wherein the external surrogate electrode is connected to a pouch into which the implantable cardiac device can is placed to form an electrical connection with the external surrogate electrode.

5. The system of claim 1, wherein the external surrogate electrode means has an area in the range of 10 cm² to 1000 cm².

6. A method for applying rescue defibrillation shocks to the heart of a patient during implantation of an implantable cardiac device having cardioverter-defibrillator capabilities, the implantable cardiac device being connected to a first electrode that is inserted in the heart and a second electrode that is located adjacent the heart, the implantable cardiac device applying defibrillation shocks to the heart between the first electrode and the second electrode for determining the defibrillation threshold of the heart, the method comprising the steps of:

attaching an external surrogate electrode to the skin of the patient;

connecting the external surrogate electrode to the implantable cardiac device with a switch, so that the external surrogate electrode is in parallel with the second electrode; and

closing the switch to electrically connect the external surrogate electrode to the implantable cardiac device to allow the implantable cardiac device to apply a rescue shock between the external surrogate electrode attached to the skin of the patient and the first electrode.

7. The method of claim 6, wherein the first electrode is a coil electrode.

8. The method of claim 6, wherein the external surrogate electrode comprises a conductive gel adhesive pad, a cable connected to the pad, and a DF-1 pin connected to the cable, the step of connecting the external surrogate electrode to the implantable cardiac device comprising the step of plugging the DF-1 pin into a DF-1 port on the implantable cardiac device.

9. The method of claim 6, wherein the second electrode is an implantable cardiac device can and wherein the external surrogate electrode further comprises a pouch, the step of connecting the external surrogate electrode to the implantable cardiac device comprising the step of inserting the implantable cardiac device can into the pouch.

10. The method of claim 6, wherein the external surrogate electrode has an area in the range of 10 cm² to 1000 cm².

11. A system for testing implantable cardioverter-defibrillators during implant comprising:

an implantable cardiac device having cardioverter-defibrillator capabilities and having an apparatus for applying rescue defibrillation shocks to the heart of a patient during implantation of the implantable cardiac device, the system further comprising;

a first electrode sized to be inserted in said heart;

a second electrode configured to be positioned adjacent said heart;

circuitry connected to the first and second electrodes, the circuitry capable of applying defibrillation shocks to the heart between the first and second electrodes for determining the defibrillation threshold of the heart during implantation of the implantable cardiac device;

an external surrogate electrode configured to be attached to the skin of the patient and to be connected to the implantable cardiac device in parallel with the second electrode during implantation of the implantable cardiac device; and

switch means for electrically connecting the external surrogate electrode to the implantable cardiac device to apply a rescue shock from the implantable cardiac device between the external surrogate electrode attached to the skin of the patient and the first electrode during implantation of the implantable cardiac device wherein the external surrogate electrode and the switch means include means for disconnecting said surrogate electrode and the switch means from the implantable cardiac device following implantation of the implanted cardiac device.

12. The system of claim 11, wherein the first electrode is a coil electrode.

13. The system of claim 11, wherein the external surrogate electrode comprises a conductive gel adhesive pad.

14. The system of claim 11, wherein the implantable cardiac device has a can and wherein the second electrode comprises said implantable cardiac device can and wherein the external surrogate electrode is connected to a pouch into which the implantable cardiac device can is placed to form an electrical connection between the implantable cardiac device can and the external surrogate electrode.

15. The system of claim 11, wherein the external surrogate electrode has an area in the range of 10 cm² to 1000 cm².

16. A system for testing implantable cardioverter-defibrillators during implant comprising:

an implantable cardiac device having cardioverter-defibrillator capabilities and having an apparatus for applying rescue defibrillation shocks to the heart of a patient during implantation, the system further comprising;

a first electrode sized to be inserted in the heart;

a second electrode configured to be positioned adjacent the heart;

circuitry connected to the first and second electrodes and capable of applying defibrillation shocks to the heart between the first and second electrodes for determining the defibrillation threshold of the heart during implantation;

a surrogate electrode pad attachable to the skin of the patient during implantation of the implantable cardiac device;

means for connecting the surrogate electrode pad in parallel with the second electrode when determining the defibrillation threshold of the heart by applying test shocks between the first electrode and the second electrode; and

means for disconnecting the surrogate electrode pad from the second electrode when the defibrillation threshold has been determined.

17. A method for applying rescue defibrillation shocks to the heart of a patient during implantation of an implantable cardiac device having cardioverter-defibrillator capabilities, the implantable cardiac device being connected to a first electrode that is inserted in the heart and a second electrode, the implantable cardiac device applying defibrillation shocks to the heart between the first electrode and the second electrode for determining the defibrillation threshold of the heart, the method comprising the steps of:

attaching a surrogate electrode pad to the skin of the patient;

connecting the surrogate electrode pad in parallel with the second electrode when determining the defibrillation threshold of the heart by applying test shocks between the first electrode and the second electrode, wherein the surrogate electrode pad reduces the effective defibrillation threshold of the heart; and

disconnecting the surrogate electrode pad from the second electrode when the defibrillation threshold has been determined.