DISCRIMINATION OF VENTRICULAR TACHYCARDIA FROM SUPRAVENTRICULAR TACHYCARDIA

• US 20090299205A1
• Filed: 06/02/2009
• Published: 12/03/2009
• Est. Priority Date: 06/02/2008
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Chow, Theodore
• Granted Patent: US 8,280,500 B2
• Time in Patent Office: Days
• US Class Current: 600/518
• CPC Class Codes: A61B 5/0006 ECG or EEG signals
• CPC Class Codes: A61B 5/02405 Determining heart rate variability
• CPC Class Codes: A61B 5/363 Detecting tachycardia or bradycardia
• CPC Class Codes: A61B 5/7264 Classification of physiological signals or data, e.g. using neural networks, statistical classifiers, expert systems or fuzzy systems neural networks per se G06N3/00; expert systems per se G06N5/00
• CPC Class Codes: A61N 1/365 controlled by a physiological parameter, e.g. heart potential evoked response A61N1/371
• CPC Class Codes: A61N 1/36585 controlled by two or more physical parameters
• CPC Class Codes: A61N 1/36592 controlled by the heart rate variability
• CPC Class Codes: G16H 50/20 for computer-aided diagnosis, e.g. based on medical expert systems

Abstract

This disclosure describes various techniques for discriminating supraventricular tachycardia (SVT) from ventricular tachycardia (VT). As one example, a method includes detecting a tachycardia rhythm, identifying a rate of change in heart rate corresponding to the tachycardia rhythm, identifying a rate of change in heart rate variability corresponding to the tachycardia rhythm, and classifying the tachycardia rhythm as at least one of supraventricular tachycardia or ventricular tachycardia based on the rate of change in heart rate and rate of change in heart rate variability.

Claims

1. A method comprising:

detecting a tachycardia rhythm;

identifying a rate of change in heart rate corresponding to the tachycardia rhythm;

identifying a rate of change in heart rate variability corresponding to the tachycardia rhythm; and

classifying the tachycardia rhythm as at least one of supraventricular tachycardia or ventricular tachycardia based on the rate of change in heart rate and rate of change in heart rate variability.

2. The method of claim 1, wherein classifying the tachycardia rhythm comprises:

classifying the tachycardia rhythm as ventricular tachycardia if the rate of change in heart rate variability exceeds both a first and second threshold; and

classifying the tachycardia rhythm as supraventricular tachycardia if the rate of change in heart rate variability does not exceed both the first and second threshold.

3. The method of claim 2, wherein classifying the tachycardia rhythm as supraventricular tachycardia comprises:

classifying the tachycardia rhythm as sinus tachycardia if the rate of change in heart rate variability does not exceed either of the first and second thresholds; and

classifying the tachycardia rhythm as atrial tachycardia if the rate of change in heart rate variability exceeds the first threshold but not the second threshold.

4. The method of claim 2, wherein values of the first and second thresholds are defined based on clinician input.

5. The method of claim 1, further comprising identifying a type of supraventricular tachycardia based on the rate of change in heart rate and rate of change in heart rate variability.

6. The method of claim 1, further comprising:

recording heart rate data for the patient over a period of time;

recording heart rate variability data for the patient over the period of time; and

identifying a relationship between heart rate and heart rate variability for the patient based on the recorded data,

wherein classifying the detected tachycardia rhythm comprises classifying the tachycardia rhythm as at least one of supraventricular tachycardia or ventricular tachycardia based on the rate of change in heart rate and rate of change in heart rate variability and the relationship.

7. A system comprising:

a sensor that senses activity of a heart of a patient; and

a processor that detects a tachycardia rhythm based on the sensed activity, identifies a rate of change in heart rate corresponding to the tachycardia rhythm, identifies a rate of change in heart rate variability corresponding to the tachycardia rhythm, and classifies the tachycardia rhythm as at least one of supraventricular tachycardia or ventricular tachycardia based on the rate of change in heart rate and rate of change in heart rate variability.

8. The system of claim 7, wherein the processor classifies the tachycardia rhythm as ventricular tachycardia if the rate of change in heart rate variability exceeds both a first and second threshold and classifies the tachycardia rhythm as supraventricular tachycardia if the rate of change in heart rate variability does not exceed both the first and second threshold.

9. The system of claim 8, wherein the processor classifies the tachycardia rhythm as sinus tachycardia if the rate of change in heart rate variability does not exceed either of the first and second thresholds and classifies the tachycardia rhythm as atrial tachycardia if the rate of change in heart rate variability exceeds the first threshold but not the second threshold.

10. The system of claim 8, wherein values of the first and second thresholds are defined based on clinician input.

11. The system of claim 7, wherein the processor identifies a type of supraventricular tachycardia based on the rate of change in heart rate and rate of change in heart rate variability.

12. The system of claim 7, further comprising a medical device, wherein the medical device comprises at least one of the sensor or the processor.

13. The system of claim 12, wherein the medical device comprises an implantable medical device.

14. The system of claim 12, wherein the sensor comprises one or more electrodes coupled to the medical device via one or more leads.

15. The system of claim 7, wherein the processor records heart rate data for the patient over a period of time based on the sensed activity, records heart rate variability data for the patient over the period of time based on the sensed activity, identifies a relationship between heart rate and heart rate variability for the patient based on the recorded data, and classifies the tachycardia rhythm as at least one of supraventricular tachycardia or ventricular tachycardia based on both the rate of change in heart rate and rate of change in heart rate variability and the relationship.

16. A system comprising:

means for detecting a tachycardia rhythm;

means for identifying a rate of change in heart rate corresponding to the tachycardia rhythm;

means for identifying a rate of change in heart rate variability corresponding to the tachycardia rhythm; and

means for classifying the tachycardia rhythm as at least one of supraventricular tachycardia or ventricular tachycardia based on the rate of change in heart rate and rate of change in heart rate variability.

17. A method comprising:

recording heart rate data for a patient over a period of time;

recording heart rate variability data for the patient over the period of time;

identifying a relationship between heart rate and heart rate variability for the patient based on the recorded data;

subsequently detecting a tachycardia rhythm in the patient; and

classifying the tachycardia rhythm as at least one of supraventricular tachycardia or ventricular tachycardia based on the relationship.

18. The method of claim 17, wherein classifying the tachycardia rhythm comprises classifying the tachycardia rhythm as supraventricular tachycardia or ventricular tachycardia based on whether the heart rate and heart rate variability are within a tolerance value of the relationship.

19. A system comprising:

a sensor that senses activity of a heart of a patient; and

a processor that records heart rate data for the patient over a period of time based on the sensed activity, records heart rate variability data for the patient over the period of time based on the sensed activity, identifies a relationship between heart rate and heart rate variability for the patient based on the recorded data, subsequently detects a tachycardia rhythm in the patient based on the sensed activity, and classifies the tachycardia rhythm as at least one of supraventricular tachycardia or ventricular tachycardia based on the relationship.

20. The system of claim 19, wherein the processor wherein classifies the tachycardia rhythm based on whether the heart rate and heart rate variability are within a tolerance value of the relationship.

21. The system of claim 19, further comprising a medical device, wherein the medical device comprises at least one of the sensor or the processor.

22. The system of claim 21, wherein the medical device comprises an implantable medical device.

23. The system of claim 21, wherein the sensor comprises one or more electrodes coupled to the medical device via one or more leads.

24. A system comprising:

means for recording heart rate data for a patient over a period of time;

means for recording heart rate variability data for the patient over the period of time;

means for identifying a relationship between heart rate and heart rate variability for the patient based on the recorded data;

means for subsequently detecting a tachycardia rhythm in the patient; and

means for classifying the tachycardia rhythm as at least one of supraventricular tachycardia or ventricular tachycardia based on the relationship.