Cardiac monitoring system

• US 9,955,913 B2
• Filed: 03/28/2017
• Issued: 05/01/2018
• Est. Priority Date: 09/30/2004
• Status: Active Grant

• Current Assignee: Zoll Medical Corporation (Asahi Kasei Corporation)
• Original Assignee: Zoll Medical Corporation (Asahi Kasei Corporation)
• Inventors: Freeman, Gary A, Totman, Mark
• Primary Examiner(s): CAREY, MICHAEL JAMES
• Application Number:
  US15/470,945
• Publication Number:
  US 20170196769A1
• Time in Patent Office: 399 Days
• Field of Search: 600508, 600509, 600516, 600518, 600521, 607 9, 607 17, 607 25
• CPC Class Codes: A61B 5/02438 with portable devices, e.g. worn by the patient
• CPC Class Codes: A61B 5/0245 by using sensing means generating electric signals, i.e. ECG signals
• CPC Class Codes: A61B 5/1116 Determining posture transitions
• CPC Class Codes: A61B 5/1118 Determining activity level
• CPC Class Codes: A61B 5/14551 for measuring blood gases
• CPC Class Codes: A61B 5/346 Analysis of electrocardiograms
• CPC Class Codes: A61B 5/4836 Diagnosis combined with treatment in closed-loop systems or methods A61B5/0036 takes precedence
• CPC Class Codes: A61B 5/7282 Event detection, e.g. detecting unique waveforms indicative of a medical condition A61B5/4094, A61B5/4818, A61B5/349, A61B5/0823 take precedence
• CPC Class Codes: A61B 7/02 Stethoscopes acoustic details thereof G10K11/00
• CPC Class Codes: A61H 2031/002 fixed on the chest by adhesives
• CPC Class Codes: A61H 2201/5007 computer controlled
• CPC Class Codes: A61H 2201/5043 Displays
• CPC Class Codes: A61H 2201/5048 Audio interfaces, e.g. voice or music controlled
• CPC Class Codes: A61H 2201/5061 Force sensors
• CPC Class Codes: A61H 2201/5084 Acceleration sensors
• CPC Class Codes: A61H 2201/5097 wireless
• CPC Class Codes: A61H 2230/04 Heartbeat characteristics, e.g. E.G.C., blood pressure modulation
• CPC Class Codes: A61H 2230/207 partial O2-value
• CPC Class Codes: A61H 31/005 with feedback for the user
• CPC Class Codes: A61H 31/007 Manual driven
• CPC Class Codes: A61N 1/046 : Specially adapted for shock therapy, e.g. defibrillation
• CPC Class Codes: A61N 1/0472 : Structure-related aspects
• CPC Class Codes: A61N 1/0492 : Patch electrodes A61N1/0412, A61N1/0428 take precedence
• CPC Class Codes: A61N 1/3625 : External stimulators
• CPC Class Codes: A61N 1/37288 : Communication to several implantable medical devices within one patient
• CPC Class Codes: A61N 1/39044 : in combination with cardiopulmonary resuscitation [CPR] therapy
• CPC Class Codes: A61N 1/39046 : User protection from shock
• CPC Class Codes: A61N 1/3968 : Constructional arrangements, e.g. casings A61N1/375 takes precedence
• CPC Class Codes: A61N 1/3987 : characterised by the timing or triggering of the shock
• CPC Class Codes: A61N 1/3993 : User interfaces for automatic external defibrillators

Abstract

A cardiac monitoring system including a long term ECG monitoring unit configured to be supported by the patient for long periods of time, including a power source, one or more electrodes electrically attached to the long term ECG monitoring unit and configured to be worn by the patient for extended periods of time, circuitry for receiving an ECG signal of the patient via the electrodes, and at least one processor operatively coupled to the circuitry for monitoring the ECG signal of the patient.

Claims

1. A cardiac monitoring system for monitoring a cardiac condition of a patient, comprising:

a long term ECG monitoring unit configured to be supported by the patient for up to 30 days comprising;

a power source;

one or more electrodes electrically attached to the long term ECG monitoring unit and configured to be worn by the patient for up to 30 days;

circuitry for receiving an ECG signal of the patient via the one or more electrodes; and

at least one processor operatively coupled to the circuitry for monitoring the ECG signal of the patient, the at least one processor configured to;

analyze the ECG signal of the patient, wherein the analyzing comprises

determining one or more intervals between adjacent R waves of QRS complexes in the ECG signal of the patient;

analyzing the ECG signal for additional one or more cardiac parameters separate from the adjacent R waves of QRS complexes in the ECG signal; and

calculating a heart rate variability based on the determined one or more intervals between adjacent R waves of the QRS complexes in the ECG of the patient; and

determine a risk probability of an impending cardiac event in the patient occurring within 24 hours based at least in part on the heart rate variability and the additional one or more cardiac parameters,

wherein if the risk probability exceeds a threshold value indicative of the impending cardiac event in the patient occurring within 24 hours, at least one of issue a prompt to the patient and communicate with a remote medical response system concerning an early warning of a heightened risk of the impending cardiac event in the patient within 24 hours.

2. The cardiac monitoring system of claim 1, further comprising a defibrillator unit configured to be electrically connected by a detachable cable to the long term ECG monitoring unit.

3. The cardiac monitoring system of claim 2, further comprising at least two defibrillator electrodes electrically coupled to the defibrillator unit.

4. The cardiac monitoring system of claim 3, further comprising a conductive adhesive disposed on one or more surfaces of the at least two defibrillation electrodes.

5. The cardiac monitoring system of claim 1, wherein the one or more electrodes are connected by at least one cable to the long term ECG monitoring unit.

6. The cardiac monitoring system of claim 1, wherein the long term ECG monitoring unit comprises a first unit that is operatively coupled to a second unit.

7. The cardiac monitoring system of claim 6, wherein the long term ECG monitoring unit is in wireless communication with the second unit.

8. The cardiac monitoring system of claim 1, wherein the impending cardiac event comprises an impending sudden cardiac arrest.

9. The cardiac monitoring system of claim 1, wherein the long term ECG monitoring unit is configured to communicate with the remote medical response system upon detecting that a cardiac event is occurring in the patient.

10. The cardiac monitoring system of claim 1, wherein the long term ECG monitoring unit is configured to communicate with the remote medical response system via at least one of a Bluetooth®

connection and a cellular network connection.

11. The cardiac monitoring system of claim 1, wherein the heart rate variability is based on a running difference between adjacent R-R intervals.

12. The cardiac monitoring system of claim 1, wherein the heart rate variability can be analyzed in at least one of a frequency domain and wavelet domain.

13. The cardiac monitoring system of claim 1, further comprising an input device configured to receive an input from the patient.

14. The cardiac monitoring system of claim 1, further comprising an input device configured to allow the patient to indicate a symptom to the long term ECG monitoring unit.

15. The cardiac monitoring system of claim 1, further comprising a memory and wherein the at least one processor is configured to record ECG information of the patient and store the ECG information to the memory.

16. The cardiac monitoring system of claim 1, further comprising a speaker for issuing prompts to the patient.

17. The cardiac monitoring system of claim 1, further comprising a display panel for providing visual prompts to the patient.

18. The cardiac monitoring system of claim 1, wherein monitoring the cardiac condition of the patient comprises monitoring for at least one of a bradycardia, tachycardia, or a ventricular flutter in the ECG signal of the patient.

19. A cardiac monitoring system for monitoring a cardiac condition of a patient, comprising:

a first unit comprising a long term ECG monitoring unit configured to be supported by the patient for up to 30 days comprising;

a power source;

one or more electrodes electrically attached to the long term ECG monitoring unit and configured to be worn by the patient for up to 30 days;

circuitry for receiving an ECG signal of the patient via the one or more electrodes; and

at least one processor electrically coupled to the circuitry for monitoring the ECG signal of the patient, the at least one processor configured to;

analyze the ECG signal of the patient, wherein the analyzing comprises

determining one or more intervals between adjacent R waves of QRS complexes in the ECG signal of the patient;

analyzing the ECG signal for additional one or more cardiac parameters separate from the adjacent R waves of QRS complexes in the ECG signal;

calculating a heart rate variability based on the determined one or more intervals between adjacent R waves of the QRS complexes in the ECG of the patient; and

determining a risk probability of an impending cardiac event in the patient occurring within 24 hours based at least in part on the heart rate variability and the additional one or more cardiac parameters,

wherein if the risk probability exceeds a threshold value indicative of an impending cardiac event in the patient occurring within 24 hours, at least one of issue a prompt to the patient and communicate with a remote medical response system concerning an early warning of a heightened risk of the impending cardiac event in the patient within 24 hours; and

a second unit detachably and communicably coupled to the first unit, wherein the second unit is configured to be worn by the patient.

20. The cardiac monitoring system of claim 19, wherein the second unit comprising a defibrillator unit configured to be electrically connected by a detachable cable to the long term ECG monitoring unit.

21. The cardiac monitoring system of claim 20, further comprising at least two defibrillator electrodes electrically coupled to the defibrillator unit.

22. The cardiac monitoring system of claim 19, wherein the long term ECG monitoring unit is configured to communicate with the remote medical response system.

23. The cardiac monitoring system of claim 19, wherein monitoring the cardiac condition of the patient comprises monitoring for at least one of a bradycardia, tachycardia, or a ventricular flutter in the ECG signal of the patient.

24. A cardiac monitoring method for monitoring a cardiac condition of a patient by a long term ECG monitoring unit, comprising:

providing a long term ECG monitoring unit configured to be supported by the patient for up to 30 days;

receiving an ECG signal of the patient via one or more electrodes electrically attached to the long term ECG monitoring unit, wherein the one or more electrodes and the long term ECG monitoring unit are configured to be worn by the patient for up to 30 days;

determining one or more intervals between adjacent R waves of QRS complexes in the ECG signal of the patient;

analyzing the ECG signal for additional one or more cardiac parameters separate from the adjacent R waves of QRS complexes in the ECG signal;

calculating a heart rate variability based on the determined one or more intervals between adjacent R waves of the QRS complexes in the ECG of the patient; and

determining a risk probability of an impending cardiac event in the patient occurring within 24 hours based at least in part on the heart rate variability and the additional one or more cardiac parameters,

wherein if the risk probability exceeds a threshold value indicative of the impending cardiac event in the patient occurring with 24 hours, at least one of issue a prompt to the patient and communicate with a remote medical response system concerning an early warning of a heightened risk of the impending cardiac event in the patient within 24 hours.

25. The cardiac monitoring method of claim 24, further comprising

providing a defibrillator unit configured to be electrically connected by a detachable cable to the long term ECG monitoring unit;

analyzing the ECG signal of the patient to detect a cardiac event; and

providing a therapeutic shock via the defibrillator unit to the patient based on the analysis if the cardiac event comprises a shockable electrical rhythm in the patient.

26. The cardiac monitoring method of claim 24, further comprising

analyzing the ECG signal of the patient to determine whether a cardiac event is occurring in the patient;

and

causing the long term ECG monitoring unit to communicate with the remote medical response system upon detecting that the cardiac event is occurring in the patient.

27. The cardiac monitoring method of claim 24, wherein monitoring the cardiac condition of the patient comprises monitoring for at least one of a bradycardia, tachycardia, or a ventricular flutter in the ECG signal of the patient.