EVALUATING A PATIENT CONDITION USING AUTONOMIC BALANCE INFORMATION IN IMPLANTABLE CARDIAC DEVICES

• US 20110137367A1
• Filed: 02/15/2011
• Published: 06/09/2011
• Est. Priority Date: 06/28/2005
• Status: Abandoned Application

• Current Assignee: Bruce H. Kenknight, Gerrard Merrill Carlson, Qingsheng Zhu
• Original Assignee: Bruce H. Kenknight, Gerrard Merrill Carlson, Qingsheng Zhu
• Inventors: Zhu, Qingsheng, Carlson, Gerrard Merrill, Kenknight, Bruce H.
• Application Number:
  US13/027,978
• Publication Number:
  US 20110137367A1
• Time in Patent Office: Days
• US Class Current: 607/17
• 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 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/4809 Sleep detection, i.e. determining whether a subject is asleep or not
• CPC Class Codes: A61B 5/4812 Detecting sleep stages or cycles
• CPC Class Codes: A61M 16/0051 with alarm devices
• CPC Class Codes: A61M 16/024 including calculation means, e.g. using a processor
• CPC Class Codes: A61M 2230/04 Heartbeat characteristics, e.g. ECG, blood pressure modulation
• CPC Class Codes: A61M 2230/10 Electroencephalographic signals
• CPC Class Codes: A61M 2230/63 Motion, e.g. physical activity
• CPC Class Codes: A61M 2230/65 Impedance, e.g. conductivity, capacity
• CPC Class Codes: A61N 1/3622 comprising two or more electrodes co-operating with different heart regions
• CPC Class Codes: A61N 1/365 controlled by a physiological parameter, e.g. heart potential evoked response A61N1/371

Abstract

Systems and methods for evaluating a patient condition using autonomic balance information involve providing an implantable cardiac device that acquires a cardiac waveform from a patient. One or more characteristics associated with autonomic balance of the patient are detected and used to evaluate a patient condition, such as sleep onset, sleep stage, cardiac vulnerability over a predetermined duration, and sleep disordered breathing. Patient activity levels may be sensed and used to evaluate the patient'"'"'s condition, such as for determining a level of systemic stress. Characteristics associated with the autonomic balance include calculating an LF/HF ratio waveform and/or determining one or more morphological features of the LF/HF ratio waveform. Coordination with a patient-external device may facilitate transmission of information about one or more of the cardiac waveform, the one or more characteristics associated with the autonomic balance, and a marked cardiac waveform.

Claims

1. A method, comprising:

acquiring a cardiac waveform from a patient using an implantable cardiac device;

detecting one or more characteristics associated with autonomic balance of the patient; and

generating a marked waveform including the acquired cardiac waveform and one or more indicators representative of the one or more characteristics.

2. The method of claim 1, comprising displaying the marked waveform on a screen.

3. The method of claim 1, comprising printing the marked waveform.

4. The method of claim 1, wherein generating the marked waveform comprises generating symbols indicative of discrete portions of the cardiac waveform corresponding to the occurrence of the one or more characteristics.

5. The method of claim 1, wherein generating the marked waveform comprises generating symbols indicative of general conditions pertaining to a continuous portion of the cardiac waveform.

6. The method of claim 1, wherein detecting the one or more characteristics comprises determining an LF/HF ratio waveform from the cardiac waveform, the LF/HF ratio waveform being a measure of the hemodynamic balance determined by dividing a power of low frequency (LF) signals of the cardiac waveform by a power of high-frequency (HF) signals of the cardiac waveform.

7. The method of claim 6, wherein detecting the one or more characteristics comprises determining one or more morphological features of the LF/HF ratio waveform.

8. The method of claim 1, comprising:

acquiring a respiration waveform;

time-aligning the marked waveform with the respiration waveform; and

displaying the marked waveform and the respiration waveform.

9. The method of claim 8, comprising deriving respiration characteristics from the respiration waveform.

10. The method of claim 9, wherein deriving the respiration characteristics comprises deriving parameters of the respiration waveform morphology.

11. The method of claim 9, wherein deriving the respiration characteristics comprises deriving parameters characterizing respiration abnormalities.

12. The method of claim 9, wherein detecting the one or more characteristics comprises determining an LF/HF ratio waveform from the cardiac waveform, the LF/HF ratio waveform being a measure of the hemodynamic balance determined by dividing a power of low frequency (LF) signals of the cardiac waveform by a power of high-frequency (HF) signals of the cardiac waveform, and comprising detecting symptoms or physiological conditions from the LF/HF ratio waveform and the respiration waveform.

13. The method of claim 9, wherein generating the marked waveform including generating symbols indicating respiration abnormalities.

14. The method of claim 9, wherein generating the marked waveform including generating symbols indicating conditions affecting respiration.

15. A system configured to communicate with a patient-internal medical device implanted in a patient, the system comprising:

a patient-external medical device configured to be communicatively coupled to the patient-interval medical device and display a marked waveform including an electrogram waveform marked with indicators of one or more characteristics associated with autonomic balance of the patient.

16. The system of claim 15, wherein the patient-external device is configured to receive the marked waveform from the patient-internal medical device.

17. The system of claim 15, wherein the patient-external device is configured to receive the electrogram waveform and the one or more characteristics from the patient-internal medical device.

18. A cardiac system, comprising:

means for acquiring a cardiac waveform from a patient;

means for sensing autonomic balance of the patient; and

means for displaying a marked waveform including the acquired cardiac waveform marked with indicators of one or more characteristics associated with the autonomic balance of the patient.

19. The system of claim 18, wherein the means for sensing the autonomic balance of the patient comprises means for calculating an LF/HF ratio being a measure of the hemodynamic balance determined by dividing a power of low frequency (LF) signals of the cardiac waveform by a power of high-frequency (HF) signals of the cardiac waveform.

20. The system of claim 19, further comprising means for delivery cardiac pacing pulses to the patient.