System and method for determining cause of irregularity within physiologic data

• US 8,996,110 B2
• Filed: 06/29/2012
• Issued: 03/31/2015
• Est. Priority Date: 06/29/2012
• Status: Active Grant

• Current Assignee: Pacesetter Incorporated (Abbott Laboratories)
• Original Assignee: Pacesetter Incorporated (Abbott Laboratories)
• Inventors: Sison, Shiloh, Mouchawar, Gabriel A.
• Primary Examiner(s): Layno, Carl H
• Assistant Examiner(s): Wu, Eugene
• Application Number:
  US13/537,714
• Publication Number:
  US 20140005496A1
• Time in Patent Office: 1,005 Days
• Field of Search: 607/6, 607/19, 607/27, 600/483, 600/513
• US Class Current: 607/27
• CPC Class Codes: A61B 2560/0223 of calibration, e.g. protocols for calibrating sensors
• CPC Class Codes: A61B 2562/0219 Inertial sensors, e.g. accelerometers, gyroscopes, tilt switches
• CPC Class Codes: A61B 5/0006 ECG or EEG signals
• CPC Class Codes: A61B 5/1116 Determining posture transitions
• CPC Class Codes: A61B 5/283 Invasive
• CPC Class Codes: A61B 5/318 Heart-related electrical modalities, e.g. electrocardiography [ECG]
• CPC Class Codes: A61B 5/686 Permanently implanted devices, e.g. pacemakers, other stimulators, biochips A61B5/6861 takes precedence
• CPC Class Codes: A61B 5/721 using a separate sensor to detect motion or using motion information derived from signals other than the physiological signal to be measured
• CPC Class Codes: A61B 5/7246 using correlation, e.g. template matching or determination of similarity
• CPC Class Codes: A61N 1/365 controlled by a physiological parameter, e.g. heart potential evoked response A61N1/371
• CPC Class Codes: A61N 1/36535 controlled by body position or posture
• CPC Class Codes: A61N 1/36542 controlled by body motion, e.g. acceleration
• CPC Class Codes: A61N 1/3702 Physiological parameters A61N1/365 takes precedence; evoked response A61N1/371

Abstract

A method for determining the cause of an irregularity in physiologic data collected by a medical device may include monitoring a collected physiologic characteristic of a patient through the physiologic data, detecting an irregularity in the physiologic data, monitoring position data of the patient, correlating the physiologic data with the position data, and determining the cause of the irregularity in the physiologic data based on correlation of the physiologic data with the position data.

Claims

1. A method for determining a cause of an irregularity in physiologic data collected by an implanted medical device (IMD), the method comprising:

monitoring and storing a collected physiologic characteristic of a patient through the physiologic data in memory of the IMD, the physiologic data collected by the IMD;

detecting an irregularity in the physiologic data, wherein the irregularity is due to a non-motion cause that is unrelated to the physiologic characteristic being monitored;

monitoring and storing position data of the patient in the memory of the IMD, the position data collected by a position detector in the IMD;

automatically correlating the physiologic data with the position data; and

determining that electromagnetic interference is the non-motion cause of the irregularity in the physiologic data when the position data does not include an aberration correlated in time with the irregularity in the physiologic data.

2. The method of claim 1, wherein the detecting operation includes automatically reviewing the physiologic data by a controller of the IMD for a deviation from a standard baseline, waveform, steady state, or pattern as the irregularity.

3. The method of claim 1, wherein the correlating operation comprises synchronizing the physiologic data with the position data over a common time frame.

4. The method of claim 1, further comprising storing in the memory of the IMD, a flagged event from the position data, the flagged event representative of a patient posture, wherein the correlating operation comprises comparing the irregularity in the physiologic data with the flagged event from the position data.

5. The method of claim 1, wherein the determining operation comprises:

detecting that the position data that correlates with the irregularity is steady; and

determining that electromagnetic interference is the non-motion cause of the irregularity based on the steady position data.

6. The method of claim 1, wherein the determining operation comprises:

detecting that the position data that correlates with the irregularity is associated with known position data readings related to patient movement; and

determining that patient movement is a motion related cause of the irregularity based on the known position data readings.

7. The method of claim 1, further comprising continually storing the physiologic data and the position data in a memory of the IMD.

8. The method of claim 1, further comprising continually storing the physiologic data and the position data in a buffer within a memory of the IMD.

9. The method of claim 1, further comprising in response to detection of the irregularity, triggering recordation of the physiologic data and the position data in the memory of the IMD.

10. The method of claim 1, wherein the correlating operation is triggered in response to the detecting of the irregularity.

11. An implantable medical device comprising:

a main housing configured to be implanted within a patient;

a position detector, in the main housing, configured to provide position data of the patient; and

a controller contained within the main housing, the controller being configured to control operation of the IMD in order to extract physiologic data from a patient, wherein the controller comprises;

inputs to collect position data and physiologic data;

a monitoring module configured to receive the position and physiologic data from the inputs and monitor a physiologic characteristic of the patient;

an irregularity-detection module configured to detect an irregularity in the physiologic data, wherein the irregularity is due to a non-motion cause that is unrelated to the physiologic characteristic being monitored;

a correlation module configured to correlate the physiologic data with the position data; and

a cause-determination module configured to determine that electromagnetic interference is the non-motion cause of the irregularity when the position data does not include an aberration correlated in time with the irregularity in the physiologic data.

12. The medical device of claim 11, wherein the position detector comprises a 3-axis accelerometer.

13. The medical device of claim 11, wherein the irregularity-detection module is configured to detect the irregularity by detecting whether an aberration occurs in the position data.

14. The medical device of claim 11, wherein the cause-determination module is configured to determine that electromagnetic interference is the non-motion cause of the irregularity when the position data that correlates with the irregularity is steady without the aberration.

15. The medical device of claim 11, wherein the cause-determination module is configured to determine that patient movement is a motion related cause of the irregularity when the position data that correlates with the irregularity is associated with known position data readings related to patient movement.

16. The medical device of claim 11, further comprising a memory within the main housing configured to store the physiologic data and the position data.

17. The medical device of claim 16, wherein the controller is configured to continually store the physiologic data and the position data in the memory.

18. The medical device of claim 16, wherein the controller is configured to continually store the physiologic data and the position data in a buffer within a memory of the IMD.

19. The medical device of claim 16, wherein the controller is configured to store the physiologic data and the position data in the memory when the irregularity is detected.