Method of operating implantable medical devices to prolong battery life

• US 20040098060A1
• Filed: 11/15/2002
• Published: 05/20/2004
• Est. Priority Date: 11/15/2002
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Ternes, David J.
• Granted Patent: US 7,016,730 B2
• Time in Patent Office: Days
• US Class Current: 607/17
• CPC Class Codes: A61N 1/3708 for power depletion

Abstract

A method of conserving power and extending the life of a battery in an implantable rate-responsive cardiac rhythm management device. In accordance with the preferred embodiment, a first physiologic sensor is used to enable a power consuming feature only when the first sensor produces an output falling within a predetermined range and subsequently disables the power consuming feature when the output of the first sensor falls back outside the predetermined range. The first sensor may measure heart rate, physical movement, posture or other parameters and the power consuming feature may comprise further physiologic sensors, a different mode of pacing or a combination thereof

Claims

1. A method for extending the battery life of an implantable cardiac rhythm management device, comprising the steps of:

a) providing a cardiac rhythm management device having a stimulation pulse generator, a microprocessor-based controller adapted to receive input signals relating to depolarization of at least one cardiac chamber and for providing control signals to the stimulation pulse generator, at least one additional power consuming feature, and a battery power supply coupled to provide electrical energy to the stimulation pulse generator, the microprocessor-based controller and selectively to the additional power consuming feature;

b) implanting the cardiac rhythm management device in a patient;

c) sensing a first physiologic parameter that varies in relation to the level of a patient'"'"'s physical activity with a first physiologic sensor;

d) determining whether the sensed physiologic parameter is within a predetermined range; and

e) enabling the at least one additional power consuming feature only if the sensed parameter is within said predetermined range.

2. The method as in claim 1 and further including the step of disabling the at least one additional power consuming device following the enabling thereof when the sensed parameter falls outside of said predetermined range.

3. The method as in claim 1 and further including the step of disabling the at least one additional power consuming device following the enabling thereof a predetermined time after a time when the sensed parameter falls outside of said predetermined range.

4. The method as in claim 1 wherein the additional power consuming feature comprises a second physiologic sensor.

5. The method of claim 4 wherein the first physiologic sensor senses movement of the patient and the second physiologic sensor measures the patient'"'"'s minute ventilation.

6. The method as in claim 5 wherein the first physiologic sensor comprises an accelerometer.

7. The method as in claim 1 wherein the first physiologic parameter comprises the patient'"'"'s intrinsic heart rate and the predetermined range is below a point where the intrinsic heart rate exhibits chronotropic incompetence.

8. The method as in claim 7 wherein the predetermined range is below the point where the intrinsic heart rate exhibits chronotropic incompetence by a predetermined safety margin.

9. The method as in claim 1 wherein the first physiologic sensor is an activity sensor and the additional power consuming feature is a rate response pacing algorithm.

10. The method as in claim 1 wherein the first physiologic sensor is a patient posture sensor and the additional power consuming feature is a rate response pacing algorithm.

11. The method as in claim 10 wherein the rate response pacing algorithm is a blended sensor rate response pacing algorithm.

12. The method as in claim 1 wherein the one additional power consuming feature is delivery of bi-ventricular pacing pulses by the stimulation pulse generator.

16. The method of claim 1 wherein the first physiologic sensor senses body motion and the at least one power consuming feature is a sleep apnea therapy device.

13. A method for extending the battery life of an implantable cardiac rhythm management device, comprising the steps of:

a) providing a cardiac rhythm management device having a stimulation pulse generator, a microprocessor-based controller adapted to receive input signals relating to depolarization of at least one cardiac chamber and for providing control signals to the stimulation pulse generator, at least one additional power consuming feature, and a battery power supply coupled to provide electrical energy to the stimulation pulse generator, the microprocessor-based controller and selectively to the additional power consuming feature;

b) implanting the cardiac rhythm management device in a patient;

c) sensing the patient'"'"'s heart rate;

d) determining when the sensed heart rate ceases to increase sufficiently to accommodate further increase in activity level;

e) initiating execution of a programmed rate response algorithm by the microprocessor-based controller.

14. The method of claim 13 and further including the step of:

switching back to execution of a non-rate response algorithm by the microprocessor-based controller when a patient'"'"'s sensed heart rate is sufficient to accommodate a current level of activity.

15. The method of claim 14 wherein the step of determining when the sensed heart rate ceases to increase sufficiently to accommodate further increase in activity level involves averaging the heart rate values where pacing initiates over a predetermined time interval during which patient activity level repeatedly varies between an at rest state and a moderately active state.