Implantable device for diagnosing and distinguishing supraventricular and ventricular tachycardias

• US 6,611,713 B2
• Filed: 11/30/2000
• Issued: 08/26/2003
• Est. Priority Date: 11/30/1999
• Status: Expired due to Term

• Current Assignee: Patrick Schauerte
• Original Assignee: Patrick Schauerte
• Inventors: Schauerte, Patrick
• Primary Examiner(s): Jastrzab, Jeffrey R.
• Application Number:
  US09/726,500
• Publication Number:
  US 20020035335A1
• Time in Patent Office: 999 Days
• Field of Search: 607/5, 607/14, 600/518
• US Class Current: 607/14
• CPC Class Codes: A61B 5/363 Detecting tachycardia or bradycardia
• CPC Class Codes: A61N 1/3622 comprising two or more electrodes co-operating with different heart regions
• CPC Class Codes: A61N 1/39622 Pacing therapy

Abstract

An implantable device for diagnosing and distinguishing supraventricular and ventricular tachycardias includes electrodes for stimulating parasympathetic nerves of the atrioventricular and/or sinus node; electrodes for stimulating the atria and ventricles and/or for ventricular cardioversion/defibrillation; a device for producing electrical parasympathetic stimulation pulses passed to the electrodes; a device for detecting the atrial and/or ventricular rate, by ascertaining a time interval between atrial and/or ventricular depolarization; a device for programming a frequency limit above which a rate of the ventricles is recognized as tachycardia; a comparison device for comparing the measured heart rate during parasympathetic stimulation to the heart rate prior to or without parasympathetic stimulation and/or to the frequency limit, which delivers an output signal when with parasympathetic stimulation the heart rate falls below the comparison value by more than a predetermined amount; and an inhibition unit which responds to the output signal to inhibit ventricular myocardial over-stimulation therapy.

Claims

1. An implantable device for diagnosing and distinguishing supraventricular and ventricular tachycardias, comprising:

electrodes for the electrical stimulation of parasympathetic nerves which innervate the atrioventricular and/or sinus node;

electrodes for the electrical stimulation of the atria and ventricles and/or for ventricular cardioversion/defibrillation;

a device for producing electrical parasympathetic stimulation pulses which are passed to the electrodes;

a detector for detecting the atrial and/or ventricular rate, by ascertaining a time interval between atrial and/or ventricular depolarization;

a device for programming a frequency limit above which a rate of the ventricles is recognized as tachycardia;

a device to start parasympathetic stimulation by sending a stimulation signal to the parasympathetic pulse producing device as long as the detector detects a ventricular rate above the tachycardia frequency limit;

a comparison device, activated in the presence of a stimulation signal, for comparing a heart rate measured by the detector during parasympathetic stimulation to the heart rate prior to or without parasympathetic stimulation and/or to the frequency limit, the comparison device delivering an output signal of a first type when the heart rate does not fall below a comparison value by more than a predetermined amount and delivering an output signal of a second type when the heart rate falls below the comparison value by more than the predetermined amount, and

an inhibition unit that responds to the output signal from the comparison device by initiating ventricular myocardial over-stimulation therapy and/or cardioversion/defibrillation therapy when the output signal of the first type is present and inhibiting ventricular myocardial over-stimulation therapy and/or cardioversion/defibrillation therepy when the output signal of the second type is present.

2. The device of claim 1 wherein the parasympathetic stimulation pulses are delivered over a defined period of time continuously.

3. The device of claim 1, further comprising:

a stimulation unit for atrial and/or ventricular electrical myocardial stimulation.

4. The device of claim 3, wherein the parasympathetic stimulation occurs at a frequency of about 20 Hz with a pulse duration between 0.1 and 4 ms.

5. The device of claim 4, wherein the parasympathetic stimulation occurs in steps which increase in a stage-wise manner.

6. The device of claim 1, wherein the parasympathetic stimulation occurs at a frequency of about 20 Hz with a pulse duration of between 0.1 and 4 ms.

7. The device of claim 6, wherein the parasympathetic stimulation occurs in steps which increase in a stage-wise manner.

8. The device of claim 1, wherein the parasympathetic stimulation occurs in steps which increase in a stage-wise manner.

9. The device as set forth in claim 1 wherein the parasympathetic stimulation pulses are delivered over a defined period of time in short pulse trains.

10. The device of claim 9, wherein the parasympathetic stimulation pulse trains are delivered in synchronized relationship with atrial or ventricular depolarization.

11. The device of claim 10, wherein the parasympathetic stimulation pulse trains are synchronized by a different time delay relative to a measured atrial/ventricular heart contraction.

12. The device of claim 11, further comprising a stimulation unit for atrial and/or ventricular electrical myocardial stimulation.

13. The device of claim 12, wherein the parasympathetic stimulation occurs at a frequency of about 20 Hz with a pulse duration of between 0.1 and 4 ms.

14. The device of claim 13, wherein the parasympathetic stimulation occurs in steps which increase in a stage-wise manner.

15. The device of claim 8, wherein the parasympathetic stimulation pulse trains are delivered asynchronously.

16. The device of claim 15, further comprising a stimulation unit for atrial and/or ventricular electrical myocardial stimulation.

17. The device of claim 16, wherein the parasympathetic stimulation occurs at a frequency of about 20 Hz with a pulse duration of between 0.1 and 4 ms.

18. The device of claim 17, wherein the parasympathetic stimulation occurs in steps which increase in a stage-wise manner.

19. The device of claim 1, further comprising a stimulation unit for cardioversion/defibrillation.