Automatic setting of cardiac operating parameters based upon capture threshold level

• US 6,925,329 B1
• Filed: 08/13/2001
• Issued: 08/02/2005
• Est. Priority Date: 08/13/2001
• Status: Expired due to Term

• Current Assignee: Pacesetter Incorporated (Abbott Laboratories)
• Original Assignee: Pacesetter Incorporated (Abbott Laboratories)
• Inventors: Sloman, Laurence S.
• Primary Examiner(s): Jastrzab, Jeffrey R.
• Assistant Examiner(s): Oropeza, Frances P.
• Application Number:
  US09/929,681
• Time in Patent Office: 1,450 Days
• Field of Search: 600/509, 600/510, 607/4, 607/5, 607/7, 607/9, 607/11, 607/27, 607/28
• US Class Current: 607/9
• CPC Class Codes: A61N 1/3712 Auto-capture, i.e. automatic adjustment of the stimulation threshold

Abstract

An apparatus and method for operating an implantable stimulation device are disclosed. The implantable stimulation device is configured to dynamically modify pacing pulse energies based upon a patient'"'"'s varying capture threshold. In at least certain situations where the implantable stimulation device modifies the pacing pulse energy, a stored value for an operating parameter, such as a ventricular blanking period or a maximum sensor rate, is automatically adjusted based upon the new pacing pulse energy. Additionally, the stored value may also be adjusted by additional variables in combination with the new pacing pulse energy.

Claims

1. A method for operating an implantable cardiac stimulation device, the method comprising:

dynamically modifying a pacing pulse energy;

determining whether one or more operating parameters, other than pacing pulse width and pacing pulse amplitude, require adjustment in response to a change in the pacing pulse energy; and

adjusting a value for an operating parameter to a new value if the operating parameter requires adjustment, wherein the new value is based upon the pacing pulse energy;

wherein the one or more operating parameters comprise at least one of a blanking period, a safety standby, a maximum sensor rate, a refractory period, a lead supervision, a fast recharge, and a block overlap.

2. The method of claim 1, wherein the pacing pulse energy comprises one of an atrial pacing pulse amplitude and a ventricular pacing pulse amplitude.

3. The method of claim 1, wherein automatically adjusting a value comprises:

determining a characteristic of the pacing pulse energy being changed;

determining one or more corresponding operating parameters based on the characteristic of the pacing pulse energy being changed;

determining one or more new values for the one or more operating parameters; and

storing the one or more new values in an appropriate memory location.

4. The method of claim 1, wherein the change in the pacing pulse energy comprises an atrial or a ventricular pacing pulse energy.

5. The method of claim 3, wherein determining one or more new values for the one or more operating parameters comprises determining the one or more new values based on the magnitude of the pacing pulse energy.

6. The method of claim 1, wherein the dynamically modifying a pacing pulse energy is performed during a capture threshold test.

7. The method of claim 1, wherein the dynamically modifying a pacing pulse energy is performed during autocapture.

8. A method for operating an implantable cardiac stimulation device, the method comprising:

dynamically modifying a pacing pulse energy;

determining an operating parameter to adjust based upon a characteristic of the pacing pulse energy that is changed, the operating parameter being other than pacing pulse amplitude and pacing pulse width;

determining a new value for the operating parameter based upon the new pacing pulse energy; and

storing the new value in a memory location associated with the operating parameter;

wherein the operating parameter comprise at least one of a blanking period, a safety standby, a maximum sensor rate, a refractory period, a lead supervision, a fast recharge, and a block overlap.

9. The method of claim 8, wherein determining a new value comprises:

accessing an operating parameter table and determining a corresponding value for the operating parameter based on the pacing pulse energy level.

10. The method of claim 8, wherein determining a new value comprises calculating the new value using a function associated with the operating parameter.

11. The method of claim 8, wherein the dynamically modifying a pacing pulse energy is performed during a capture threshold test.

12. An implantable stimulation device comprising:

a pulse generator that generates stimulation pulses;

cardiac sensing circuitry that generates sense signals; and

a control unit coupled with the pulse generator and the cardiac sensing circuitry, the control unit being configured to;

determine a capture threshold based on one or more signals from the sensing circuitry;

adjust a pacing pulse output energy in response to a change in capture threshold; and

modify a value for one or more operating parameters when the pacing pulse output energy has been changed, wherein the one or more operating parameters are other than pacing pulse width and pacing pulse amplitude, wherein a new value is based upon a new pacing pulse energy; and

wherein the one or more operating parameters comprise at least one of a blanking period, a safety standby, a maximum sensor rate, a refractory period, a lead supervision, a fast recharge, and a block overlap.

13. The implantable stimulation device of claim 12, wherein the control unit comprises a microcontroller and a control program, and wherein the implantable stimulation device further comprises a memory.

14. The implantable stimulation device of claim 13, wherein the control program causes the microcontroller to perform the modifying operation by:

checking the memory to determine whether auto-adjustment of the operating parameter is enabled;

determining the new value for the operating parameter if auto-adjustment of the operating parameter is enabled; and

storing the new value in a memory location in the memory that is associated with the operating parameter.

15. The implantable stimulation device of claim 13, wherein the control program causes the microcontroller to determine the new value by:

converting the new pacing pulse energy into an array index; and

using the array index to identify an element of an array containing the new value, wherein the array is associated with the operating parameter.

16. The implantable stimulation device of claim 15, wherein the elements of the array are programmable.

17. The implantable stimulation device of claim 13, wherein the control program causes the microcontroller to determine the new value by calculating the new value using a function associated with the operating parameter.

18. The implantable stimulation device of claim 17, wherein the function associated with the operating parameter is programmable.

19. The implantable stimulation device of claim 12, wherein the pacing pulse energy comprises an atrial pacing pulse amplitude.

20. An implantable stimulation device comprising:

means for generating a stimulation pulse having a pulse energy level;

means for sensing cardiac activity;

means for modifying the pulse energy level; and

means for adjusting a value for an operating parameter when the pulse energy level has been modified, wherein the operating parameter is other than pacing pulse width and pacing pulse amplitude, wherein the adjusted value is based upon the modified pulse energy level; and

wherein the operating parameter comprises at least one of a blanking period, a safety standby, a maximum sensor rate, a refractory period, a lead supervision, a fast recharge, and a block overlap.

21. The implantable stimulation device of claim 20, wherein the means for modifying the pulse energy level is performed during a capture threshold test.

22. The implantable stimulation device of claim 20, wherein the means for modifying the pulse energy level is performed during autocapture.