Cardiac stimulation device including sleep apnea prevention and treatment

• US 20030153956A1
• Filed: 09/18/2002
• Published: 08/14/2003
• Est. Priority Date: 02/14/2002
• Status: Active Grant

• Current Assignee: Euljoon Park, Gene A. Bornzin, Steve Koh
• Original Assignee: Euljoon Park, Gene A. Bornzin, Steve Koh
• Inventors: Koh, Steve, Bornzin, Gene A., Park, Euljoon
• Granted Patent: US 7,212,862 B2
• Time in Patent Office: Days
• US Class Current: 607/17
• CPC Class Codes: A61N 1/3601 of respiratory organs
• CPC Class Codes: A61N 1/36542 controlled by body motion, e.g. acceleration
• CPC Class Codes: A61N 1/36557 controlled by chemical substances in blood
• CPC Class Codes: A61N 1/36585 controlled by two or more physical parameters

Abstract

An implantable cardiac stimulation device comprises a physiologic sensor and one or more pulse generators. The physiologic sensor is capable of sensing a physiologic parameter. The pulse generators can generate cardiac pacing pulses with a timing based on the physiologic parameter. The timed cardiac pacing pulses can prevent a sleep apnea condition. In one example, a cardiac stimulation device has a physiologic sensor and can be configured to pace a patient'"'"'s heart according to a rest mode of operation. The cardiac stimulation device uses measurements from the physiologic sensor to prevent and treat sleep apnea using a revised rest mode of operation. The revised rest mode operates under a presumption that sleep apnea is primary to a reduced heart rate, rather than secondary, so that pacing at a rate higher than the natural cardiac rate during sleep will prevent sleep apnea.

Claims

1. An implantable cardiac stimulation device for stimulating a heart of a patient, the device comprising:

at least one physiologic sensor that is capable of sensing at least one physiologic parameter and generating corresponding signals;

one or more pulse generators that are capable of generating cardiac pacing pulses; and

circuitry connected to the at least one sensor and that is operative to detect a rest condition of the patient based on the signals and to control the one or more pulse generators to pace the heart at a rest rate, wherein the rest rate is initially set to a first value, wherein the circuitry is further operative to determine if the patient experiences a predetermined number of sleep apnea episodes based on the signals from the at least one physiologic sensor, and wherein the circuitry is responsive to the detection of the predetermined number of sleep apnea episodes to adjust the rest rate to a sleep apnea prevention value, wherein the sleep apnea prevention value is higher than the first value.

2. An implantable cardiac stimulation device according to claim 1 further comprising:

a controller coupled to the one or more pulse generators and to the one or more physiologic sensors, the controller comprising an executable control logic that distinguishes between a sleeping condition and a waking condition of a patient.

3. An implantable cardiac stimulation device according to claim 1 further comprising:

a physiologic sensor that measures physical motion for derivation of an activity parameter and an activity variance parameter, and activates sleep apnea preventive pacing when the activity and activity variance signals indicate a sleeping condition.

4. An implantable cardiac stimulation device according to claim 1 further comprising:

a physiologic sensor that measures QT interval, and wherein the circuitry adjusts the rest rate to the sleep apnea prevention value when the QT interval exceeds a threshold value.

5. An implantable cardiac stimulation device according to claim 1 further comprising:

a physiologic sensor that measures cardiac conductivity, and wherein the circuitry adjusts the rest rate to the sleep apnea prevention value when cardiac conductivity is depressed during sleep.

6. An implantable cardiac stimulation device according to claim 1 further comprising:

a physiologic sensor that measures cardiac contractility, and wherein the circuitry adjusts the rest rate to the sleep apnea prevention value when cardiac contractility is reduced during sleep.

7. An implantable cardiac stimulation device according to claim 1 further comprising:

a physiologic sensor that measures evoked response amplitude and evoked response duration, and wherein the circuitry adjusts the rest rate to the sleep apnea prevention value when evoked response amplitude is decreased and evoked response duration is increased during sleep.

8. An implantable cardiac stimulation device according to claim 7 further comprising:

a physiologic sensor that measures paced depolarization integral (PDI), and wherein the circuitry adjusts the rest rate to the sleep apnea prevention value when PDI is depressed during sleep.

9. An implantable cardiac stimulation device according to claim 1 further comprising:

a physiologic sensor that measures stroke volume, and wherein the circuitry adjusts the rest rate to the sleep apnea prevention value when stroke volume increases when a patient is in a supine position.

10. An implantable cardiac stimulation device according to claim 1 further comprising:

a physiologic sensor that measures blood oxygen concentration, and wherein the circuitry adjusts the rest rate to the sleep apnea prevention value when blood oxygen concentration is depressed during sleep.

11. An implantable cardiac stimulation device according to claim 1 further comprising:

a physiologic sensor that measures blood carbon dioxide concentration, and wherein the circuitry adjusts the rest rate to the sleep apnea prevention value when blood carbon dioxide concentration is elevated during sleep.

12. The implantable cardiac stimulation device of claim 1 wherein the predetermined number of sleep apnea episodes is at least one.

13. An implantable cardiac stimulation device comprising:

means for setting a rest rate to a first value for a patient;

means for determining if the patient experiences a predetermined number of sleep apnea episodes; and

means for adjusting the rest rate to a sleep apnea prevention value when the means for determining determines that the patient experiences a predetermined number of sleep apnea episodes, wherein the sleep apnea prevention value is higher than the first value.

14. An implantable cardiac stimulation device according to claim 13 further comprising:

means for distinguishing between a sleeping condition and a waking condition of a patient.

15. An implantable cardiac stimulation device according to claim 13 wherein the means for determining comprises at least one of:

a physiologic sensor that measures physical motion for derivation of an activity parameter and an activity variance parameter;

a physiologic sensor that measures QT interval;

a physiologic sensor that measures cardiac conductivity;

a physiologic sensor that measures cardiac contractility;

a physiologic sensor that measures evoked response integral amplitude and evoked response duration;

a physiologic sensor that measures stroke volume;

a physiologic sensor that measures paced depolarization integral (PDI); and

a physiologic sensor that measures blood oxygen concentration.

16. A method of operating an implantable cardiac stimulation device, the method comprising:

setting a rest rate to a first value for a patient;

monitoring the patient for a predetermined number of sleep apnea episodes; and

adjusting the rest rate to a sleep apnea prevention value when a predetermined number of sleep apnea episodes are detected, where the sleep apnea prevention value is higher than the first value.

17. The method of claim 16, further comprising:

distinguishing between a sleeping condition and a waking condition of a patient;

timing generation of the cardiac pacing pulses; and

controlling the timed cardiac pacing pulses at a sleep apnea prevention rate.

18. A method according to claim 16 further comprising:

distinguishing between a sleeping condition and a waking condition of a patient; and

timing cardiac pacing pulse generation to pace at a rate greater than the resting rate in response to detection of a sleeping condition.

19. The method of claim 16, wherein adjusting comprises adjusting the rest rate when at least one sleep apnea episode is detected.

20. The method of claim 16, wherein adjusting comprises adjusting the rest rate when a plurality of sleep apnea episodes are detected.