Systems and methods for infarct detection

• US 10,226,631 B2
• Filed: 08/23/2016
• Issued: 03/12/2019
• Est. Priority Date: 08/28/2015
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Kane, Michael J., Shuros, Allan Charles, Schmidt, Brian L., Maile, Keith R., Haasl, Benjamin J.
• Primary Examiner(s): Stice, Paula J
• Application Number:
  US15/244,740
• Publication Number:
  US 20170056667A1
• Time in Patent Office: 931 Days
• CPC Class Codes: A61B 2562/0219 Inertial sensors, e.g. accelerometers, gyroscopes, tilt switches
• CPC Class Codes: A61B 5/0004 characterised by the type of physiological signal transmitted
• CPC Class Codes: A61B 5/0022 Monitoring a patient using a global network, e.g. telephone networks, internet
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/02405 Determining heart rate variability
• CPC Class Codes: A61B 5/02455 provided with high/low alarm devices
• CPC Class Codes: A61B 5/1104 induced by stimuli or drugs; A61B5/1102 takes precedence; investigating medicinal preparations G01N33/15
• CPC Class Codes: A61B 5/1107 Measuring contraction of parts of the body, e.g. organ, muscle apparatus for measuring work or force in general G01L
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/4836 Diagnosis combined with treatment in closed-loop systems or methods A61B5/0036 takes precedence
• 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 5/7246 using correlation, e.g. template matching or determination of similarity
• CPC Class Codes: A61B 5/742 using visual displays A61B5/339 takes precedence
• 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 1/36578 controlled by mechanical motion of the heart wall, e.g. measured by an accelerometer or microphone
• CPC Class Codes: G16H 40/67 for remote operation

Abstract

Systems, devices, and methods for determining occurrences of myocardial infarctions are disclosed. In one embodiment, a method of sensing for an occurrence of a myocardial infarction may include sensing a baseline accelerometer signal during a baseline, determining a baseline template based on one or more characteristics of the baseline accelerometer signal, and storing the baseline template in a memory. The method may further include sensing an accelerometer signal during a test period subsequent to the baseline, determining a test template based on one or more characteristics of the accelerometer signal during the test period, and comparing the baseline template with the test template, and based on the comparison, determining if a myocardial infarction occurred in the patient'"'"'s heart. If it is determined that a myocardial infarction occurred in the patient'"'"'s heart, the method may further include displaying an indication on a display that a myocardial infarction occurred.

Claims

1. A method of sensing for an occurrence of a myocardial infarction in a patient'"'"'s heart using a leadless cardiac pacemaker that is affixed to the patient'"'"'s heart, the method comprising:

sensing, by the leadless cardiac pacemaker, a baseline first sensor signal generated via a first sensor of the leadless cardiac pacemaker during a baseline period, the first sensor comprising one or more of a cardiac electrical signal sensor, a heart sound sensor, and an isovolumic contraction period sensor;

sensing, by the leadless cardiac pacemaker, a baseline accelerometer signal generated via an accelerometer of the leadless cardiac pacemaker during the baseline period that reflects movement of the patient'"'"'s heart during the baseline period;

determining a baseline template based on one or more characteristics of the baseline first sensor signal and the baseline accelerometer signal;

storing the baseline template in a memory;

sensing, by the leadless cardiac pacemaker, the baseline first sensor signal generated via the first sensor during a first test period subsequent to the baseline period;

determining a first test template based on one or more characteristics of the first sensor signal during the test period;

comparing the first test template with the baseline template, and based on the comparison, determining if a myocardial infarction may have occurred in the patient'"'"'s heart;

when it is determined that a myocardial infarction may have occurred in the patient'"'"'s heart, then;

sensing, by the leadless cardiac pacemaker, the accelerometer signal generated via the accelerometer during a second test period subsequent to the first test period that reflects movement of the patient'"'"'s heart during the second test period;

determining a second test template based on one or more characteristics of the accelerometer signal during the second test period;

comparing the second test template with the baseline template, and based on the comparison, determining if a myocardial infarction occurred in the patient'"'"'s heart;

communicating information from the leadless cardiac pacemaker to an external device; and

when it is determined that a myocardial infarction occurred in the patient'"'"'s heart based on the comparison of the second test template with the baseline template, displaying an indication on a display of the external device that a myocardial infarction occurred in the patient'"'"'s heart.

2. The method of claim 1, further comprising:

transmitting an output signal for reception by the external device that is located external to the patient indicating that a myocardial infarction occurred in the patient'"'"'s heart.

3. The method of claim 2, wherein the external device is a device programmer.

4. The method of claim 2, wherein the external device is a cellular telephone.

5. The method of claim 1, wherein the memory is part of the leadless cardiac pacemaker.

6. The method of claim 1, wherein the baseline template and the first test template are compared by the leadless cardiac pacemaker.

7. The method of claim 1, wherein the leadless cardiac pacemaker determines if a myocardial infarction occurred in the patient'"'"'s heart.

8. The method of claim 1, wherein the memory is part of the external device that is located external to the patient.

9. The method of claim 1, wherein the baseline template and the first test template are compared by the external device that is located external to the patient.

10. The method of claim 1, wherein the external device is located external to the patient and determines if a myocardial infarction occurred in the patient'"'"'s heart.

11. A method of sensing for an occurrence of a myocardial infarction in a patient'"'"'s heart using a leadless cardiac pacemaker that is affixed to the patient'"'"'s heart, the method comprising:

determining when one or more baseline conditions exist;

when the one or more baseline conditions exist, then;

sampling, by the leadless cardiac pacemaker, a baseline accelerometer signal generated via an accelerometer of the leadless cardiac pacemaker during a baseline period that reflects movement of the patient'"'"'s heart during the baseline period;

storing in a memory one or more characteristics of the baseline accelerometer signal sensed during the baseline period;

after storing in the memory the one or more characteristics of the baseline accelerometer signal sensed during the baseline period, determining when the one or more baseline conditions again exist;

when the one or more baseline conditions again exist;

sampling, by the leadless cardiac pacemaker, an accelerometer signal generated via the accelerometer that reflects movement of the patients'"'"' heart during a test period;

comparing one or more characteristics of the accelerometer signal sampled during the test period with the one or more characteristics of the baseline accelerometer signal sampled during the baseline period, and based on the comparison, determining if a myocardial infarction occurred in the patients'"'"' heart;

communicating information from the leadless cardiac pacemaker to an external device; and

when it is determined that a myocardial infarction occurred in the patient'"'"'s heart, displaying an indication on a display of the external device that a myocardial infarction occurred in the patient'"'"'s heart.

12. The method of claim 11, wherein the memory is part of the leadless cardiac pacemaker.

13. The method of claim 11, wherein the one or more characteristics of the accelerometer signal sampled during the test period and the one or more characteristics of the baseline accelerometer signal sampled during the baseline period are compared by the leadless cardiac pacemaker.

14. The method of claim 11, wherein the leadless cardiac pacemaker determines if a myocardial infarction occurred in the patient'"'"'s heart.

15. The method of claim 11, wherein the external device is located external to the patient and determines if a myocardial infarction occurred in the patient'"'"'s heart.

16. The method of claim 11, wherein the one or more baseline conditions comprises one or more of a baseline activity level condition, a baseline heart rate condition, and a baseline posture condition.