System and method for determining a reference baseline for use in heart failure assessment

• US 20070293741A1
• Filed: 08/20/2007
• Published: 12/20/2007
• Est. Priority Date: 07/26/1999
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Bardy, Gust
• Granted Patent: US 8,888,698 B2
• Time in Patent Office: Days
• US Class Current: 600/301
• CPC Class Codes: A61B 5/0002 Remote monitoring of patients using telemetry, e.g. transmission of vital signals via a communication network A61B5/07 takes precedence; transmission systems for measured values G08C; transmission H04B; transmission of digital information H04L; wireless communication networks H04W
• CPC Class Codes: A61B 5/4884 inducing physiological or psychological stress, e.g. applications for stress testing
• CPC Class Codes: A61B 5/7278 Artificial waveform generation or derivation, e.g. synthesising signals from measured signals A61B5/327 takes precedence
• CPC Class Codes: A61B 5/7282 Event detection, e.g. detecting unique waveforms indicative of a medical condition A61B5/4094, A61B5/4818, A61B5/349, A61B5/0823 take precedence
• CPC Class Codes: G16H 10/60 for patient-specific data, e.g. for electronic patient records
• CPC Class Codes: G16H 40/67 for remote operation
• CPC Class Codes: G16H 50/30 for calculating health indices; for individual health risk assessment
• CPC Class Codes: G16H 70/00 ICT specially adapted for the handling or processing of medical references

Abstract

A system and method for determining a stressor-based reference baseline for use in heart failure assessment is presented. A patient is monitored during an observation time period while the patient performs prescribed physical stressors and by applying pacing stimulus stressors to a medical device. Physiological measures are stored from the observation period, including at least one of direct measures regularly recorded on a substantially continuous basis by the medical device and measures derived therefrom. The measures that originate from the observation time period as a reference baseline for the patient are identified. The reference baseline and those measures originating subsequent to the observation period are evaluated. The measures are analyzed to detect any trends, including one of a status quo and a change in cardiac performance of the patient. Each trend is compared to parameters corresponding to worsening heart failure indications to generate a notification of parameter violations.

Claims

1. A system for determining a reference baseline for use in heart failure assessment, comprising:

a data module to assemble physiological measures, which were directly recorded as data on a substantially continuous basis by an implantable medical device for a patient or indirectly derived from the data;

a reference baseline module to identify those of the physiological measures that originate from an observation time period as a reference baseline for the patient; and

an evaluation module to evaluate the physiological measures, comprising;

an analysis module to determine patient wellness comprising one of a status quo and a change in cardiac performance relative to the reference baseline; and

a comparison module to compare the patient wellness to worsening heart failure indications.

2. A system according to claim 1, further comprising:

a quality of life module to associate quality of life measures contemporaneously chronicled by the patient over the observation time period.

3. A system according to claim 1, wherein the change in cardiac performance is selected from the group comprising an onset, progression, and regression of a cardiac performance parameter.

4. A system according to claim 1, wherein the worsening heart failure indications are selected from the group comprising pulmonary artery pressure, left atrial pressure, dyspnea, orthopnea, pulmonary edema, peripheral edema, and fatigue.

5. A system according to claim 1, further comprising:

a sensor to measure one or more of pulmonary artery pressure, heart rate, heart sounds, intrathoracic impedance, respiration, posture, lung fluid, activity, weight, and physiological response to activity.

6. A system according to claim 1, wherein the patient is monitored while performing prescribed physical stressors and experiencing pacing stimulus stressors during the observation time period.

7. A system according to claim 1, further comprising:

a reprogramming module to reprogram a medical device based on evaluation of the physiological measures.

8. A system according to claim 7, wherein the worsening heart failure indications are factored into the reprogramming.

9. A system according to claim 1, wherein respiration rate is tracked through the medical device, further comprising:

a notification module to generate a notification triggered by a parameter assigned to the respiration rate.

10. A system according to claim 9, wherein the parameter comprises one or more of an upper limit parameter applied over a short term and a counter parameter applied over a long term.

11. A system according to claim 1, wherein the medical device comprises one of an implantable medical device and an external medical device.

12. A method for determining a reference baseline for use in heart failure assessment, comprising:

assembling physiological measures, which were directly recorded as data on a substantially continuous basis by an implantable medical device for a patient or indirectly derived from the data;

identifying those of the physiological measures that originate from an observation time period as a reference baseline for the patient; and

evaluating the physiological measures by determining patient wellness comprising one of a status quo and a change in cardiac performance relative to the reference baseline and comparing the patient wellness to worsening heart failure indications.

13. A method according to claim 12, further comprising:

associating quality of life measures contemporaneously chronicled by the patient over the observation time period.

14. A method according to claim 12, wherein the change in cardiac performance is selected from the group comprising an onset, progression, and regression of a cardiac performance parameter.

15. A method according to claim 12, wherein the worsening heart failure indications are selected from the group comprising pulmonary artery pressure, left atrial pressure, dyspnea, orthopnea, pulmonary edema, peripheral edema, and fatigue.

16. A method according to claim 12, further comprising:

measuring one or more of pulmonary artery pressure, heart rate, heart sounds, intrathoracic impedance, respiration, posture, lung fluid, activity, weight, and physiological response to activity.

17. A method according to claim 12, further comprising:

monitoring the patient while performing prescribed physical stressors and experiencing pacing stimulus stressors during the observation time period.

18. A method according to claim 12, further comprising:

reprogramming a medical device based on evaluation of the physiological measures.

19. A method according to claim 18, further comprising:

factoring the worsening heart failure indications into the reprogramming.

20. A method according to claim 12, further comprising:

tracking respiration rate through the medical device; and

generating a notification triggered by a parameter assigned to the respiration rate.

21. A method according to claim 20, wherein the parameter comprises one or more of an upper limit parameter applied over a short term and a counter parameter applied over a long term.

22. A method according to claim 12, wherein the medical device comprises one of an implantable medical device and an external medical device.

23. A system for determining a stressor-based reference baseline for use in heart failure assessment, comprising:

a programmer to receive monitoring of a patient that was performed during an observation time period while the patient performed prescribed physical stressors and while pacing stimulus stressors were applied to a medical device of the patient;

a storage module to store physiological measures from the observation period comprising at least one of direct measures regularly recorded on a substantially continuous basis by the medical device and measures derived therefrom;

a reference baseline module to identify those of the physiological measures that originate from the observation time period as a reference baseline for the patient; and

an evaluation module to evaluate the reference baseline and those physiological measures originating subsequent to the observation period, comprising;

an analyzer module to analyze the direct measures and the derived measures to detect any trends comprising one of a status quo and a change in cardiac performance of the patient; and

a comparison module to compare each such trend to parameters corresponding to worsening heart failure indications to generate a notification of parameter violations.

24. A system according to claim 23, further comprising:

a reprogramming module to reprogram a medical device based on extended evaluation of the direct measures and the derived measures.

25. A system according to claim 23, further comprising:

a tracking module to track respiration rate of the patient on a regular basis through the medical device; and

a notification module to generate a notification triggered by one or more of an upper limit parameter applied over a short term and a counter parameter applied over a long term.

26. A method for determining a stressor-based reference baseline for use in heart failure assessment, comprising:

monitoring a patient during an observation time period while the patient performs prescribed physical stressors and by applying pacing stimulus stressors to a medical device of the patient;

storing from the observation period physiological measures comprising at least one of direct measures regularly recorded on a substantially continuous basis by the medical device and measures derived therefrom;

identifying those of the physiological measures that originate from the observation time period as a reference baseline for the patient; and

evaluating the reference baseline and those physiological measures originating subsequent to the observation period, comprising;

analyzing the direct measures and the derived measures to detect any trends comprising one of a status quo and a change in cardiac performance of the patient; and

comparing each such trend to parameters corresponding to worsening heart failure indications to generate a notification of parameter violations.

27. A method according to claim 26, further comprising:

reprogramming a medical device based on extended evaluation of the direct measures and the derived measures.

28. A method according to claim 26, further comprising:

tracking respiration rate of the patient on a regular basis through the medical device; and

generating a notification triggered by one or more of an upper limit parameter applied over a short term and a counter parameter applied over a long term.