Arrhythmia discrimination using electrocardiograms sensed from multiple implanted electrodes

• US 20060253044A1
• Filed: 05/09/2005
• Published: 11/09/2006
• Est. Priority Date: 05/09/2005
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Meyer, Scott A., Stahmann, Jeffrey E., Zhang, Yi, McCabe, Aaron R., Yu, Yinghong, Ricci, Carlos Alberto
• Granted Patent: US 7,917,196 B2
• Time in Patent Office: Days
• US Class Current: 600/512
• CPC Class Codes: A61B 5/341 Vectorcardiography [VCG]
• CPC Class Codes: A61B 5/7203 for noise prevention, reduction or removal

Abstract

Cardiac monitoring and/or stimulation methods and systems provide for monitoring, diagnosing, defibrillation and pacing therapies, or a combination of these capabilities, including cardiac systems incorporating or cooperating with neuro-stimulating devices, drug pumps, or other therapies. Embodiments of the present invention relate generally to implantable medical devices employing automated cardiac activation sequence monitoring and/or tracking for arrhythmia discrimination. Embodiments of the invention are directed to devices and methods involving sensing a plurality of composite cardiac signals using a plurality of implantable electrodes. A source separation is performed using the sensed plurality of composite cardiac signals and the separation produces one or more cardiac signal vectors associated with one or more cardiac activation sequences that is indicative of ischemia. A change of the one or more cardiac signal vectors is detected using the one or more cardiac signal vectors. Cardiac arrhythmias are discriminated using the one or more cardiac signal vectors.

Claims

1. A cardiac method, comprising:

sensing a plurality of composite cardiac signals using a plurality of implantable electrodes;

performing a source separation using the sensed plurality of composite cardiac signals;

producing one or more cardiac signal vectors associated with all or a portion of one or more cardiac activation sequences based on the source separation; and

discriminating cardiac arrhythmias using the one or more cardiac signal vectors.

2. The method of claim 1, wherein discriminating the cardiac arrhythmias comprises detecting a change in a characteristic of the one or more cardiac signal vectors relative to a baseline of the one or more cardiac signal vectors.

3. The method of claim 1, wherein discriminating the cardiac arrhythmias comprises discriminating between one or more of:

arrhythmia and non-arrhythmia;

supra-ventricular tachycardia and ventricular tachycardia;

polymorphic ventricular tachycardia and monomorphic ventricular tachycardia;

left-ventricular tachycardia and right-ventricular tachycardia; and

premature atrial contraction and premature ventricular contraction.

4. The method of claim 1, wherein discriminating the cardiac arrhythmias comprises determining the beat-to-beat variance of a characteristic of the one or more cardiac signal vectors.

5. The method of claim 1, wherein discriminating the cardiac arrhythmias comprises discriminating premature atrial contraction by detecting a positive phase of a dominant orientation of the one or more cardiac signal vectors.

6. The method of claim 1, wherein discriminating the cardiac arrhythmias comprises discriminating premature ventricular contraction by detecting a negative phase of a dominant orientation of one or more cardiac signal vectors.

7. The method of claim 1, wherein discriminating the cardiac arrhythmias comprises discriminating between one or more of:

supra-ventricular tachycardia and atrioventricular nodal supra-ventricular tachycardia;

left atrial supra-ventricular tachycardia and right atrial supra-ventricular tachycardia; and

ventricular tachycardia and ventricular fibrillation.

8. A cardiac method, comprising:

sensing a plurality of composite cardiac signals using a plurality of implantable electrodes;

performing a source separation using the detected plurality of composite cardiac signals, the source separation producing a plurality of vectors;

selecting one or more vectors from the plurality of vectors;

storing information associated with the selected one or more vectors; and

using the stored information to discriminate cardiac arrhythmias.

9. The method of claim 8, wherein performing the source separation comprises determining a cardiac activation sequence.

10. The method of claim 8, wherein the cardiac arrhythmias are discriminated by detecting a change in a cardiac activation sequence.

11. The method of claim 8, wherein a plurality of the subsequent source separations are performed on a beat-to-beat basis.

12. A cardiac system, comprising:

a plurality of implantable electrodes configured for sensing a composite signal, thereby providing a plurality of composite cardiac signals;

a housing configured for implantation in a patient;

a memory provided in the housing; and

a controller provided in the housing and coupled to the memory and the plurality of implantable electrodes, the controller configured to perform a source separation using the sensed plurality of composite cardiac signals, the source separation producing one or more cardiac signal vectors associated with all or a portion of one or more cardiac activation sequences, and to discriminate cardiac arrhythmias using the one or more cardiac signal vectors.

13. The system of claim 12, comprising therapy circuitry coupled to the controller and configured to deliver a cardiac therapy in response to the discriminated arrhythmia.

14. The system of claim 12, comprising a signal processor provided in a patient-external device or system, the signal processor and the controller coupled to respective communication devices to facilitate wireless communication between the signal processor and controller.

15. The system of claim 12, comprising a signal processor provided in a network server system, the signal processor and the controller coupled to respective communication devices to facilitate wireless communication between the signal processor and controller.

16. The system of claim 12, comprising a lead configured for subcutaneous non-intrathoracic placement in a patient and coupled to the controller, wherein at least one of the plurality of implantable electrodes is supported by the lead.

17. The system of claim 12, wherein the housing comprises a header configured for coupling a lead to the housing, and at least one of the plurality of implantable electrodes is provided on the header.

18. The system of claim 12, wherein at least one of the plurality of implantable electrodes is provided on the housing.

19. The system of claim 12, comprising a lead coupled to the controller, wherein at least two of the plurality of implantable electrodes are supported by the lead.

20. The system of claim 12, wherein the plurality of implantable electrodes comprise at least four electrodes, wherein one of the at least four electrodes does not lie in the same plane as the other of the at least four electrodes.

21. The system of claim 12, wherein the source separation algorithm comprises a blind source separation algorithm.