Multi-sensor strategy for heart failure patient management

• US 9,161,698 B2
• Filed: 04/09/2014
• Issued: 10/20/2015
• Est. Priority Date: 10/10/2008
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Zhang, Yi, Stahmann, Jeffrey E., Siejko, Krzysztof Z., Thompson, Julie A., Hatlestad, John D., Beck, Kenneth C., Wariar, Ramesh
• Primary Examiner(s): MALAMUD, DEBORAH LESLIE
• Application Number:
  US14/248,949
• Publication Number:
  US 20140221786A1
• Time in Patent Office: 559 Days
• Field of Search: 600/301, 600508-509, 600/515, 607 1- 2, 607115-116, 607/119
• US Class Current: 1/1
• CPC Class Codes: A61B 5/0008 Temperature signals
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/01 Measuring temperature of body parts ; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue clinical contact thermometers G01K13/20
• CPC Class Codes: A61B 5/02028 Determining haemodynamic parameters not otherwise provided for, e.g. cardiac contractility or left ventricular ejection fraction
• 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 5/02055 Simultaneously evaluating both cardiovascular condition and temperature
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61B 5/026 Measuring blood flow A61B3/1233, A61B3/1241 take precedence
• CPC Class Codes: A61B 5/029 Measuring or recording blood output from the heart, e.g. minute volume A61B8/065 takes precedence
• CPC Class Codes: A61B 5/0531 Measuring skin impedance
• CPC Class Codes: A61B 5/0538 invasively, e.g. using a catheter
• CPC Class Codes: A61B 5/0816 Measuring devices for examining respiratory frequency measuring frequency of electric signals G01R23/00
• CPC Class Codes: A61B 5/085 Measuring impedance of respiratory organs or lung elasticity
• CPC Class Codes: A61B 5/1118 Determining activity level
• CPC Class Codes: A61B 5/121 evaluating hearing capacity
• CPC Class Codes: A61B 5/14542 for measuring blood gases A61B5/14551 takes precedence
• CPC Class Codes: A61B 5/283 Invasive
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/686 Permanently implanted devices, e.g. pacemakers, other stimulators, biochips A61B5/6861 takes precedence
• CPC Class Codes: A61B 5/6869 Heart
• 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 7/00 : Instruments for auscultation
• CPC Class Codes: A61B 7/04 : Electric stethoscopes microphones, acoustic transducers therefor H04R
• CPC Class Codes: A61N 1/36585 : controlled by two or more physical parameters
• CPC Class Codes: G16H 50/20 : for computer-aided diagnosis, e.g. based on medical expert systems

Abstract

An apparatus comprises plurality of sensors and a processor. Each sensor provides a sensor signal that includes physiological information and at least one sensor is implantable. The processor includes a physiological change event detection module that detects a physiological change event from a sensor signal and produces an indication of occurrence of one or more detected physiological change events, and a heart failure (HF) detection module. The HF detection module determines, using a first rule, whether the detected physiological change event is indicative of a change in HF status of a subject, determines whether to override the first rule HF determination using a second rules, and declares whether the change in HF status occurred according to the first and second rules.

Claims

1. A system comprising:

a plurality of sensors, each sensor configured to provide a sensor signal, wherein the sensor signal includes physiological information;

an implantable device comprising;

at least one of the sensors;

a sampling circuit, communicatively coupled to the implantable sensors, configured to provide a sampled sensor signal; and

a first communication circuit, communicatively coupled to the sampling circuit, configured to communicate the sampled sensor signal to a second device; and

an external device comprising;

a second communication circuit configured to communicate with the implantable device; and

a processor, communicatively coupled to the second communication circuit, wherein the processor includes;

a physiological change event detection module configured to;

detect a physiological change event from a sensor signal including at least one sampled sensor signal communicated from the implantable device; and

produce an indication of occurrence of one or more physiological change events; and

a heart failure (HF) detection module configured to;

determine whether the detected physiological change events are indicative of a change in HF status using a first rule;

determine whether to override the first rule HF determination using a second rule; and

generate an indication of whether the change in HF status occurred according to the first and second rules.

2. The system of claim 1, wherein the first rule includes indicating a change in HF status when a majority of a set of detectable physiological change events is detected.

3. The system of claim 2, wherein the second rule includes:

overriding a negative first rule HF determination according to a specificity of a detected physiological change event; and

overriding a positive first rule HF determination according to a negative predictive value of a physiological change event.

4. The system of claim 1, wherein the first rule includes indicating the change in HF status when a majority of a set of detectable physiological change events is detected.

5. The system of claim 1, wherein the second rule includes overriding a negative first rule HF determination when a condition for an S3 heart sound is met in a heart sound signal.

6. The system of claim 1, wherein the second rule includes overriding a positive first rule HF determination when a condition in a physiologic response to patient activity is met.

7. The system of claim 1, wherein the HF detection module weights the second rule HF determination greater than the first rule HF determination.

8. The system of claim 1,

wherein the physiological change event detection module is configured to weight the detected physiological change event according to the sensor signal, and

wherein the HF detection module is configured to:

determine a likelihood that the change in HF status occurred using the weight of the physiological change event; and

provide an alert based on the declared HF event, wherein the alert includes an indication of the likelihood that the change in HF status occurred.

9. The system of claim 8, wherein the HF detection module is configured to determine a level of urgency of the alert according to the first and second rules.

10. The system of claim 8, wherein the HF detection module is configured to generate an indication of one of a plurality of levels of urgency of the alert according to the first and second rules.

11. The system of claim 1, wherein the plurality of sensors includes at least one of:

an implantable impedance sensor, an implantable respiration sensor, and an implantable intra-thoracic total impedance (ITTI) sensor.

12. The system of claim 1, wherein the plurality of sensors includes at least one of an implantable activity sensor and an implantable electrocardiogram sensor.

13. The system of claim 1, wherein the plurality of sensors includes an implantable heart sound sensor.

14. The system of claim 1, wherein the plurality of sensors includes at least one of:

an implantable blood pressure sensor;

an implantable oxygen saturation sensor;

an implantable blood flow sensor; and

an implantable temperature sensor.

15. The system of claim 1, wherein the physiologic change detector is configured to detect a physiological change event related to total work of the lett ventricle using a sensor signal including at least one sampled sensor signal communicated from the implantable device.

16. The system of claim 1,

wherein the physiological change event detection module is configured to:

compare a sensor signal from a sensor of the plurality of sensors to a specified threshold; and

assign one indication of a plurality of indications of occurrence of a physiological change event to the sensor signal according to the comparison;

wherein the HF detection module is configured to;

accumulate indications assigned to the sensors signals provided by plurality of sensors; and

determine whether the detected physiological change events are indicative of a change in HF status using the accumulated indications.

17. The system of claim 16, wherein the detection module is configured to assign a weight to the indication of a change in HF status using the accumulated indications assigned to the sensor signals.

18. The system of claim 16, wherein the physiological change event detection module is configured to assign one of three or more indications of a physiological change event to the sensor signal according to a comparison to a plurality of specified thresholds.

19. The system of claim 16, wherein the HF detection module is configured to override indications assigned to a first set of sensor signals according to an indication assigned to a sensor signal different from the first set of sensor signals.

20. The system of claim 16, wherein an indication assigned to a sensor signal is reflective of a strength of the indication of the occurrence of a physiological change event, and wherein the HF detection module is configured to assign the weight to the indication of a change in HF status using the accumulated strength indications assigned to the sensor signals.