Within-patient algorithm to predict heart failure decompensation

• US 8,031,076 B2
• Filed: 11/05/2009
• Issued: 10/04/2011
• Est. Priority Date: 12/27/2006
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Stalsberg, Kevin J., Sachanandani, Haresh G., Sweeney, Robert J., Cazares, Shelley M., Peterson, Jon
• Primary Examiner(s): HOFSASS, JEFFERY A
• Application Number:
  US12/613,007
• Publication Number:
  US 20100045467A1
• Time in Patent Office: 698 Days
• Field of Search: 340/573.1, 340/540, 600/481, 600/483, 600/484, 600/485, 600/508
• US Class Current: 340/573.1
• CPC Class Codes: A61B 2560/0242 adapted to measure environmental factors, e.g. temperature, pollution
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/0205 Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition
• CPC Class Codes: A61B 5/02455 provided with high/low alarm devices
• 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 5/0816 Measuring devices for examining respiratory frequency measuring frequency of electric signals G01R23/00
• 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 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/318 Heart-related electrical modalities, e.g. electrocardiography [ECG]
• CPC Class Codes: A61B 5/7275 Determining trends in physiological measurement data; Predicting development of a medical condition based on physiological measurements, e.g. determining a risk factor
• CPC Class Codes: A61B 5/746 Alarms related to a physiological condition, e.g. details of setting alarm thresholds or avoiding false alarms alarms per se G08B
• CPC Class Codes: A61N 1/3627 for treating a mechanical deficiency of the heart, e.g. congestive heart failure or cardiomyopathy
• CPC Class Codes: A61N 1/37252 Details of algorithms or data aspects of communication system, e.g. handshaking, transmitting specific data or segmenting data
• CPC Class Codes: G16H 40/67 for remote operation
• CPC Class Codes: G16H 50/30 for calculating health indices; for individual health risk assessment

Abstract

This document discusses, among other things, systems and methods for predicting heart failure decompensation using within-patient diagnostics. A method comprises detecting an alert status of each of one or more sensors; calculating an alert score by combining the detected alerts; and calculating a composite alert score, the composite alert score being indicative of a physiological condition and comprising a combination of two or more alert scores.

Claims

1. A method comprising:

detecting an alert status of one or more detectors, the alert status being indicative of a first event occurring in a first timeframe;

calculating an alert score at by combining the alert status of the one or more detectors;

calculating a composite alert score, the composite alert score being indicative of a likelihood of an onset of a physiological condition and comprising a combination of two or more alert scores;

comparing the composite alert score to a composite alert score threshold; and

providing an indication of the likelihood of the onset of the physiological condition when the composite alert score violates the composite alert score threshold.

2. The method of claim 1, wherein detecting the alert status of the one or more detectors includes:

detecting a parameter of one or more sensors coupled to the one or more detectors;

comparing the parameter to one or more threshold values to obtain a result; and

using the result to detect the alert status.

3. The method of claim 2, wherein the parameter includes one of sensed physiological data, sensed environmental data, or a data collected from a patient in response to a query or request.

4. The method of claim 3, wherein the sensed physiological data includes cardiac indications, physical activity, or indications of patient compliance.

5. The method of claim 2, wherein the one or more sensors include an implantable medical device.

6. The method of claim 2, comprising:

choosing an initial value for the one or more threshold values; and

dynamically adjusting the one or more threshold values to improve one or more performance measures related to false positives or false negatives for a patient.

7. The method of claim 6, wherein choosing the initial value includes using a value determined during a learning period.

8. The method of claim 1, wherein the alert status is indicative of a heart failure decompensation condition.

9. The method of claim 1, wherein the composite alert score is indicative of a likelihood of a heart failure decompensation condition, a likelihood of death, or a likelihood of a change in quality of life, in a second timeframe.

10. The method of claim 1, wherein the likelihood of the onset of the physiological condition indicates a likelihood of the physiological condition presently occurring.

11. The method of claim 1, wherein the likelihood of the onset of the physiological condition indicates a likelihood of the physiological condition occurring in the future.

12. A system comprising:

a patient device comprising;

a communication module adapted to detect an alert status of one or more detectors, the alert status being indicative of a first event occurring in a first timeframe; and

an analysis module adapted to;

calculate an alert score by combining the detected alerts;

calculate a composite alert score, the composite alert score being indicative of a likelihood an onset of a physiological condition and comprising a combination of two or more alert scores; and

compare the composite alert score to a composite alert score threshold to obtain a result;

wherein the communication module is adapted to provide an indication of the likelihood of the onset of a physiological condition when the result indicates that the composite alert score violates the composite alert score threshold.

13. The system of claim 12, comprising:

one or more sensors coupled to the one or more detectors;

wherein the one or more detectors are adapted to;

detect a parameter from the one or more sensors;

compare the parameter to one or more threshold values to obtain a result; and

use the result to obtain the alert status.

14. The system of claim 13, wherein the one or more sensors include an electrocardiogram, an accelerometer, a pressure sensor, a cardiac output detector, a heart rate monitor, an interrogatory device, a weight scale, or a microphone.

15. The system of claim 13, wherein the one or more sensors include an implantable medical device.

16. The system of claim 13, wherein the parameter includes one of sensed physiological data, sensed environmental data, or a data collected from a patient in response to a query or request.

17. The system of claim 13, wherein the one or more detectors are adapted to:

choose an initial value for the one or more threshold values; and

dynamically adjust the one or more threshold values to improve one or more performance measures related to false positives or false negatives for a patient.

18. The system of claim 17, wherein the one or more detectors are adapted to choose the initial value using a value determined during a learning period.

19. A machine-readable medium including instructions, which when executed on a machine, cause the machine to:

detect an alert status of one or more detectors, the alert status being indicative of a first event occurring in a first timeframe;

calculate an alert score at by combining the alert status of the one or more detectors;

calculate a composite alert score, the composite alert score being indicative of a likelihood of an onset of a physiological condition and comprising a combination of two or more alert scores;

compare the composite alert score to a composite alert score threshold; and

provide an indication of the likelihood of the onset of the physiological condition when the composite alert score violates the composite alert score threshold.

20. An apparatus comprising:

means for detecting an alert status of one or more detectors, the alert status being indicative of a first event occurring in a first timeframe;

means for calculating an alert score at by combining the alert status of the one or more detectors;

means for calculating a composite alert score, the composite alert score being indicative of a likelihood of an onset of a physiological condition and comprising a combination of two or more alert scores;

means for comparing the composite alert score to a composite alert score threshold; and

means for providing an indication of the likelihood of the onset of the physiological condition when the composite alert score violates the composite alert score threshold.