Core body temperature monitoring in heart failure patients

• US 7,037,273 B2
• Filed: 05/22/2002
• Issued: 05/02/2006
• Est. Priority Date: 05/22/2002
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Zhu, Qingsheng, Spinelli, Julio
• Primary Examiner(s): NASSER, ROBERT L
• Application Number:
  US10/154,142
• Publication Number:
  US 20030220582A1
• Time in Patent Office: 1,441 Days
• Field of Search: 607 17- 23, 600/549, 600/482, 600/483
• US Class Current: 600/549
• CPC Class Codes: A61B 5/0008 Temperature signals
• CPC Class Codes: A61B 5/024 Detecting, measuring or recording pulse rate or heart rate A61B5/0205, A61B5/021 take precedence
• CPC Class Codes: A61B 5/076 Permanent implantations telemetry using implanted circuitry A61B5/0031; implanted stimulators for therapy A61N1/3605, A61N1/362, A61N1/372
• CPC Class Codes: A61B 5/145 Measuring characteristics of blood in vivo, e.g. gas concentration, pH value; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid, cerebral tissuemeasuring of blood pressure or blood flow A61B5/02; non-radiation detecting or locating of foreign bodies in blood A61B5/06
• CPC Class Codes: A61B 5/14539 for measuring pH

Abstract

An implanted heart monitor includes sensors that measure various aspects of the heart failure patient'"'"'s heart. A remote heart monitoring system connects the implanted heart monitor to a care provider, such as a physician. The data provided by the implanted heart monitor permits the care provider to obtain valuable data on the heart in order to make health care decisions affecting the heart failure patient'"'"'s treatment. In many cases, the measurement of core body temperature and other patient data will enable the care provider to alter the patient'"'"'s treatment to address the patient'"'"'s condition. The implanted heart monitor can communicate over a wireless communication link with an external monitor. The implanted heart monitor may be implemented as part of a pacing device (i.e., pace maker) or may be a separate unit devoted to monitoring functions. The external monitor communicates with a monitoring station over a communication link. The monitoring station can operate as a centralized data collection unit, collecting data from multiple external monitors and multiple implanted heart monitors. Various other aspects of a heart failure patient'"'"'s heart and/or body can be monitored, such as heart rate, blood pH levels, blood CO₂ levels, and any other indications of the heart failure patient'"'"'s activity. Various predetermined thresholds may be set to trigger alarms and/or data reports.

Claims

1. A heart monitoring system, comprising:

a temperature sensor for determining a core body temperature of a patient;

a bodily activity sensor for determining a bodily activity level of the patient; and

a heart monitor operatively connected to the temperature sensor and bodily activity sensor and configured to receive data representative of the core body temperature and the bodily activity level;

the heart monitor further being configured to generate an alarm message upon determination that a relationship between the core body temperature and the bodily activity level is outside of a predefined range.

2. The heart monitoring system of claim 1, wherein the temperature sensor is of a configuration that allows the temperature sensor to be implanted in the patient'"'"'s body.

3. The heart monitoring system of claim 1, wherein the bodily activity sensor is of a configuration that allows the bodily activity sensor to be implanted in the patient'"'"'s body.

4. The heart monitoring system of claim 1, wherein the heart monitor is of a configuration that allows the external monitor to be implanted in the patient'"'"'s body.

5. The heart monitoring system of claim 1, wherein the heart monitor is of a configuration that allows the heart monitor to be outside the patient'"'"'s body and wherein the heart monitoring system includes a wireless communication link that allows wireless communications between the temperature sensor, bodily activity sensor and heart monitor.

6. The heart monitoring system of claim 1, wherein the heart is operative to determine a relationship between the core body temperature and the bodily activity level.

7. The heart monitoring system of claim 6, wherein the heart monitor is further operative to determine the slope of a two-dimensional representation of the relationship between the core body temperature and the bodily activity level.

8. The heart monitoring system of claim 6, wherein the heart monitor is further operative to generate an alarm when the relationship between the core body temperature and the bodily activity level is outside of a predetermined acceptable range.

9. The heart monitoring system of claim 6, wherein the heart monitor is further operative to transmit an alarm to a remote monitoring station, when the relationship between the core body temperature and the bodily activity level is outside of a predetermined acceptable range.

10. The heart monitoring system of claim 1, wherein the heart monitor is further operative transmit the core body temperature and the bodily activity level to a remote monitoring station.

11. A method for diagnosing a performance level of a heart in a patient, comprising the steps of:

determining a core body temperature;

determining a bodily activity level;

determining a relationship between the core body temperature and the bodily activity level; and

generating a first alarm message, in response to determining that the relationship between the core body temperature and the bodily activity level is outside of a predetermined acceptable relationship range.

12. The method of claim 11, further comprising the steps of:

determining whether the core body temperature is within a predetermined acceptable temperature range; and

generating a second alarm message, in response to determining that the core body temperature is outside of a predetermined acceptable temperature range.

13. The method of claim 12, further comprising the step of altering a patient treatment regimen, in response to determining that the core body temperature is outside of a predetermined acceptable temperature range.

14. The method of claim 11, further comprising the steps of:

determining whether the bodily activity level is within a predetermined acceptable activity level range; and

generating a third alarm message, in response to determining that the core body temperature is outside of a predetermined acceptable activity level range.

15. The method of claim 14, further comprising the step of altering a patient treatment regimen, in response to determining that the core body temperature is outside of a predetermined acceptable activity level range.

16. The method of claim 11, wherein the step of determining the bodily activity level comprises determining a patient blood pH level.

17. The method of claim 11, wherein the step of determining the bodily activity level comprises determining a patient ventilation rate.

18. The method of claim 11, wherein the step of determining the bodily activity level comprises determining a patient acceleration level.

19. The method of claim 11, further comprising the step of altering a patient treatment regimen, in response to a determination that the relationship between the core body temperature and the bodily activity level is outside of the predetermined acceptable relationship range.

20. An implantable heart monitor, comprising:

a core body temperature sensor for determining a core body temperature of a patient;

a bodily activity sensor for determining a bodily activity level of a patient;

a transmission unit for transmitting the core body temperature and the bodily activity level to an external monitor; and

a processing unit for calculating a relationship between the core body temperature and the bodily activity level and for generating an alarm message in response to a determination that the relationship is outside of a predefined acceptable range;

wherein the transmission unit is further operative to transmit the alarm message to the external monitor.

21. The implantable heart monitor of claim 20, further comprising a pacing unit for pacing one or more of the patient'"'"'s heart chambers.

22. The implantable heart monitor of claim 20, wherein the core body temperature sensor determines the core body temperature by sensing a myocardial muscle temperature and by correlating the myocardial muscle temperature to the core body temperature.

23. The implantable heart monitor of claim 20, wherein the core body temperature sensor determines the core body temperature by sensing a skeletal muscle temperature and by correlating the skeletal muscle temperature to the core body temperature.

24. The implantable heart monitor of claim 20, wherein the core body temperature sensor determines the core body temperature by sensing a skin temperature and by correlating the skin temperature to the core body temperature.

25. The implantable heart monitor of claim 20, wherein the core body temperature sensor determines the core body temperature by sensing a blood pH level and by correlating the blood pH level to the core body temperature.

26. The implantable heart monitor of claim 20, wherein the bodily activity sensor determines the bodily activity level by sensing a blood pH level and by correlating the blood pH level to the bodily activity level.

27. The implantable heart monitor of claim 20, wherein the bodily activity sensor determines the bodily activity level by sensing a blood CO₂ level and by correlating the blood CO₂ level to the bodily activity level.

28. The implantable heart monitor of claim 20, wherein the bodily activity sensor determines the bodily activity level by sensing a patient ventilation rate and by correlating the patient ventilation rate to the bodily activity level.

29. The implantable heart monitor of claim 20, wherein the bodily activity sensor determines the bodily activity level by sensing an oxygen consumption level and by correlating the oxygen consumption level to the bodily activity level.

30. A heart monitoring system, comprising:

an implanted heart monitor having;

a temperature sensor for determining a core body temperature of a patient;

a bodily activity sensor for determining a bodily activity level of the patient; and

a communication link for transmitting the core body temperature and the bodily activity level to an external monitor; and

the external monitor operative to transmit the core body temperature and the bodily activity level to a care provider;

wherein the implanted heart monitor is operative to send an alarm message to the external monitor in response to a determination that a relationship between the core body temperature and the bodily activity level is outside of a predefined acceptable range.

31. An implantable heart monitor, comprising:

a core temperature level means for determining a core body temperature of a patient;

an activity level means for determining a bodily activity level of a patient;

a transmission means for transmitting the core body temperature and the bodily activity level to an external monitor; and

a processing means for calculating a relationship between the core body temperature and the bodily activity level and for generating an alarm message in response to a determination that the relationship is outside of a predefined acceptable range;

wherein the transmission means is further operative to transmit the alarm message to the external monitor.