Reducing false positives in detection of potential cardiac pauses

• US 10,194,816 B2
• Filed: 03/03/2017
• Issued: 02/05/2019
• Est. Priority Date: 03/04/2016
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Perschbacher, David L., Mahajan, Deepa, Siejko, Krzysztof Z., Thakur, Pramodsingh H., Maile, Keith R., An, Qi
• Primary Examiner(s): GETZOW, SCOTT M
• Application Number:
  US15/449,890
• Publication Number:
  US 20170251940A1
• Time in Patent Office: 704 Days
• CPC Class Codes: A61B 5/0022 Monitoring a patient using a global network, e.g. telephone networks, internet
• 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 5/024 Detecting, measuring or recording pulse rate or heart rate A61B5/0205, A61B5/021 take precedence
• CPC Class Codes: A61B 5/0245 by using sensing means generating electric signals, i.e. ECG signals
• CPC Class Codes: A61B 5/0809 by impedance pneumography
• CPC Class Codes: A61B 5/0816 Measuring devices for examining respiratory frequency measuring frequency of electric signals G01R23/00
• CPC Class Codes: A61B 5/165 Evaluating the state of mind, e.g. depression, anxiety
• CPC Class Codes: A61B 5/318 Heart-related electrical modalities, e.g. electrocardiography [ECG]
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/364 Detecting abnormal ECG interval, e.g. extrasystoles, ectopic heartbeats
• CPC Class Codes: A61B 5/686 Permanently implanted devices, e.g. pacemakers, other stimulators, biochips A61B5/6861 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: A61B 7/005 Detecting noise caused by implants, e.g. cardiac valves
• CPC Class Codes: A61B 7/04 Electric stethoscopes microphones, acoustic transducers therefor H04R
• CPC Class Codes: A61N 1/36 for stimulation
• CPC Class Codes: A61N 1/36521 the parameter being derived from measurement of an electrical impedance
• CPC Class Codes: A61N 1/36535 controlled by body position or posture
• 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: A61N 1/3702 Physiological parameters A61N1/365 takes precedence; evoked response A61N1/371
• CPC Class Codes: A61N 1/3925 Monitoring; Protecting
• CPC Class Codes: A61N 1/3943 : for threshold determination
• CPC Class Codes: A61N 1/3962 : in combination with another heart therapy

Abstract

Embodiments of the disclosure include systems and methods for reducing false positives in detection of pauses. For example, embodiments include a sensing component configured to obtain values of a first physiological parameter and determine a cardiac pause based on the values of the first physiological parameter. Furthermore, embodiments include performing a validation check of the determined cardiac pause using at least one of: the values of the first physiological parameter or values of a second physiological parameter.

Claims

1. A system comprising:

a sensing component configured to be operatively coupled to a patient and to obtain values of a first physiological parameter; and

at least one processor configured to;

determine a potential cardiac pause of the patient using the values of the first physiological parameter and at least one episode criterion;

perform a validation check of the potential cardiac pause using at least one validation criterion and at least one of;

the values of the first physiological parameter or values of a second physiological parameter; and

adapt, in response to the validation check, at least one of the at least one episode criterion and the at least one validation criterion.

2. The system of claim 1, wherein the values of the first physiological parameter are values of an electrogram.

3. The system of claim 2, wherein the potential cardiac pause is determined when at least one of the following occurs:

(1) a first R-R interval of the electrogram is greater than a time threshold, wherein the first R-R interval is identified using a first electric potential, or (2) a subsequent R wave does not occur within a specified period of time after an R wave is identified, wherein the R wave is identified using the first electric potential threshold.

4. The system of claim 3, wherein the at least one processor performs the validation check by calculating a second R-R interval and wherein an R wave of the second R-R interval is identified using a second electric potential threshold, the second electric potential threshold being less than the first electric potential threshold.

5. The system of claim 1, wherein the values of the second physiological parameter are obtained from a heart sound sensor and wherein the at least one processor performs the validation check by determining whether the second physiological parameter includes values indicative of heart sounds following a fiducial of the first physiological parameter.

6. The system of claim 5, wherein the heart sounds include at least one of:

an S1 heart sound, an S2 heart sound, an S3 heart sound and an S4 heart sound.

7. The system of claim 1, wherein the at least one processor is configured to confirm the validation check by performing at least one of:

a morphological analysis of the electrogram and a frequency analysis of the electrogram.

8. The system of claim 1, wherein the values of the second physiological parameter are obtained from at least one of the following:

a second electrogram, an activity sensor, a posture sensor, a heart sound sensor and an impedance sensor.

9. The system of claim 1, wherein the at least one processor comprises:

a first processing circuit disposed in an implantable medical device (IMD), the first processing circuit configured to determine the potential cardiac pause of the patient; and

a second processing circuit disposed in the IMD, the second processing circuit configured to perform the validation check.

10. A system comprising:

a sensing component configured to be operatively coupled to a patient and to obtain values of a first physiological parameter, wherein the values of the first physiological parameter are values of an electrogram;

at first processing circuit configured to;

(1) identify a first R wave peak using a first electric potential threshold;

(2) identify a second R wave peak using the first electric potential threshold;

(3) determine, based on the first and second R wave peaks, a first R-R interval; and

(4) determine a potential cardiac pause of the patient by determining that the first R-R interval is greater than a time threshold; and

a second processing circuit configured to perform a validation check of the potential cardiac pause using at least one validation criterion and at least one of the values of the first physiological parameter or values of a second physiological parameter;

wherein at least one of the first processing circuit and the second processing circuit is configured to adapt, in response to the validation check, at least one of the first electric potential threshold, the time threshold, and the at least one validation criterion.

11. The system of claim 10, wherein the sensing component and at least one of the first processing circuit and second processing circuit are disposed in an implantable medical device (IMD).

12. The system of claim 11, wherein the sensing component and at least one of the first processing circuit and the second processing circuit are disposed in a wearable medical device.

13. The system of claim 10, wherein the sensing component and the first processing circuit are disposed in an implantable medical device (IMD), the system further comprising an external monitoring device (EMD) configured to be disposed outside the patient'"'"'s body, the EMD comprising the second processing circuit.

14. The system of claim 10, wherein the second processing circuit performs the validation check by (1) identifying, between the first and second R wave peaks, a third R wave peak using a second electric potential threshold;

(2) determining a second R-R interval, based on the third R wave peak; and

(3) determining whether the second R-R interval exceeds the time threshold.

15. The system of claim 10, wherein the second processing circuit is configured to confirm the validation check by performing at least one of a:

morphological analysis of the electrogram and a frequency analysis of the electrogram.

16. The system of claim 10, the second physiological parameter comprising at least one of activity, posture, heart sounds and impedance.

17. A method comprising:

obtaining values of a first physiological parameter of a patient;

determining, using the values of the first physiological parameter and at least one episode criterion, a potential cardiac pause of the patient;

performing a validation check of the potential cardiac pause using at least one validation criterion and at least one of the values of the first physiological parameter or values of a second physiological parameter; and

adapting, in response to the validation check, at least one of the at least one episode criterion and the at least one validation criterion.

18. The method of claim 17, wherein determining the potential cardiac pause includes determining when a first R-R interval is greater than a time threshold, wherein an R wave of the first R-R interval is identified using a first electric potential threshold, and wherein performing the validation check includes determining a second R-R interval of the electrogram during the potential cardiac pause, the second R-R interval comprising an additional R wave, wherein the additional R wave is identified using a second electric potential threshold.

19. The method of claim 18, wherein the first electric potential threshold is at least 33% greater than the second electric potential threshold.

20. The method of claim 18, wherein performing the validation check includes using values obtained from at least one of:

a second electrogram, an activity sensor, a posture sensor, a heart sound sensor and an impedance sensor.