Method and apparatus for preventing clotting during a trial fibrillation

• US 6,230,056 B1
• Filed: 09/08/1999
• Issued: 05/08/2001
• Est. Priority Date: 05/31/1994
• Status: Expired due to Fees

• Current Assignee: Galvani, Ltd.
• Original Assignee: Galvani, Ltd.
• Inventors: Kroll, Kai
• Primary Examiner(s): Kamm, William E.
• Application Number:
  US09/393,443
• Time in Patent Office: 608 Days
• Field of Search: 607/4, 607/5, 607/6, 607/14
• US Class Current: 607/9
• CPC Class Codes: A61N 1/306 Arrangements where at least part of the apparatus is introduced into the body
• CPC Class Codes: A61N 1/3621 for treating or preventing abnormally high heart rate
• CPC Class Codes: A61N 1/3624 occurring in the atrium, i.e. atrial tachycardia
• CPC Class Codes: A61N 1/3625 External stimulators
• CPC Class Codes: A61N 1/3918 characterised by shock pathway, e.g. by electrode configuration
• CPC Class Codes: A61N 1/3925 Monitoring; Protecting
• CPC Class Codes: A61N 1/395 for treating atrial fibrillation
• CPC Class Codes: A61N 1/3956 Implantable devices for applying electric shocks to the heart, e.g. for cardioversion

Abstract

A device for preventing clotting during atrial fibrillation includes optional electrical cardiac output forcing (ECOF) or ICD/AED back up. The device includes a power supply for operating the device and for providing the necessary output forcing signals. The power supply is located in a housing which may be implantable into a human patient. In one embodiment, the housing acts as an electrode. At least one additional electrode is connected to the housing and may be inserted into the human heart. A ventricular lead is mounted to the electrode along with an atrial lead. The housing also contains an electrical cardiac stimulator. When a certain cardiac event, such as atrial fibrillation, is detected, anti-clotting pulses are applied to the heart via the atrial lead. If and when ventricular fibrillation is detected, further pulses of a different voltage level are applied to the heart via the ventricular lead. In one embodiment, the anti-clotting pulses are synchronized to the R-wave sensed by the ventricular lead.

Claims

1. An implantable device for preventing clotting during atrial fibrillation comprising:

an implantable housing;

at least one electrode connected to the housing;

an atrial lead mounted to the at least one electrode; and

a cardiac stimulator in the housing electrically connected to the atrial lead through the at least one electrode wherein the atrial lead applies anti-clotting pulses upon the occurrence of atrial fibrillation.

2. The device of claim 1 further comprising a ventricular lead mounted to the at least one electrode.

3. The device of claim 2 in which said cardiac stimulator is connected to both the atrial lead and the ventricular lead.

4. The device of claim 1 in which the housing forms an electrode.

5. The device of claim 3 in which the atrial lead and ventricular lead further comprise at least one ECG sensor.

6. The device of claim 1, further comprising a control circuit in the housing electrically connected to the at least one electrode, wherein the control circuit applies the anti-clotting pulses in synchronization with a sensed R-wave of the patient'"'"'s heart.

7. The device of claim 1 in which the anti-clotting pulses are between 10 and 100 Volts.

8. The device of claim 1 in which ECOF pulses are applied to the ventricular lead upon the occurrence of ventricular fibrillation.

9. The device of claim 1 in which at least one ICD shock pulse is applied to the ventricular lead upon the occurrence of ventricular fibrillation.

10. A device for preventing thrombogenic cardiac events in a human and for simultaneously protecting against life threatening effects of possible ventricular rhythm abnormalities, comprising:

an ECG detector for detecting both atrial and ventricular fibrillation; and

an electrical cardiac stimulator connected to the ECG detector and configured for producing anti-clotting pulses deliverable to the atrium upon the occurrence of at least one potentially thrombogenic cardiac event and for producing cardiac output forcing signals upon the occurrence of ventricular fibrillation.

11. The device of claim 10 in which the ECG detector detects R-waves of the patient'"'"'s heart.

12. The device of claim 10 in which the anti-clotting pulses and the cardiac output forcing signals are greater than about 10 volts and less than a normal ICD shock voltage.

13. The device of claim 10 in which the cardiac output forcing signals are at a voltage level of a normal ICD shock.

14. The device of claim 10 in which the anti-clotting pulses are configured for delivery to the atrium of the patient'"'"'s heart in synchronization with a detected portion of an electrocardiogram.

15. A device for preventing clotting during atrial fibrillation comprising:

power supply means;

detection means connected to the power supply means;

output control means connected to the detection means and to the power supply means for delivering anti-clotting pulses to the atrium of the patient'"'"'s heart upon the detection of atrial fibrillation and for delivering cardiac therapy signals to a ventricle of the patient'"'"'s heart upon the detection of ventricular fibrillation.

16. The device of claim 15 in which the detection means comprises an ECG sensor.

17. The device of claim 15 further comprising electrode means for delivering said pulses and signals to the atrium and the ventricle.

18. The device of claim 15 in which the anti-clotting pulses and the cardiac therapy signals are greater than about 10 volts and less than a normal ICD shock voltage.

19. The device of claim 15 in which the cardiac therapy signals are at a voltage level of a normal ICD shock.

20. A method of preventing clotting during atrial fibrillation comprising the steps of:

a) monitoring the cardiac rhythm of a patient'"'"'s heart; and

b) applying anti-clotting electrical pulses to an atrium of the patient'"'"'s heart upon the detection of a first predetermined cardiac event.

21. The method of claim 20 further comprising the step of applying a cardiac therapy signal to the heart upon the detection of a second predetermined cardiac event.

22. The method of claim 20 in which the first predetermined cardiac event is atrial fibrillation.

23. The method of claim 20 in which the first predetermined cardiac event is the occurrence of at least one potentially thrombogenic cardiac event.

24. The method of claim 21 in which the second predetermined cardiac event is ventricular fibrillation.

25. The method of claim 21, further comprising the step of synchronizing the anti-clotting pulses to the R-wave of the QRS complex of the patient'"'"'s heart.

26. The method of claim 21 in which the duration of the anti-clotting pulses is determined according to the cardiac needs of each user of the method.

27. The method of claim 21 in which the anti-clotting pulses are applied for a duration of between about 5 seconds and about 60 seconds.

28. The method of claim 21 in which a time period between a plurality of successive anti-clotting pulses is selected between about 1 hour and about 72 hours for users of the method having chronic atrial fibrillation.

29. A method for preventing cardiac thrombogenesis resulting from atrial disrhythmia, comprising the steps of:

a) monitoring the atrial rate of a patient'"'"'s heart;

b) comparing the atrial rate to a threshold value to detect atrial fibrillation;

c) delivering anti-clotting electrical pulses to an atrium of the patient'"'"'s heart when the threshold atrial rate is exceeded.

30. The method of claim 29, further comprising the step of monitoring the atrial rate after delivery of the anti-clotting electrical pulses, and if the atrial rate continues to exceed the threshold value then to re-apply the anti-clotting electrical pulses.

31. The method of claim 29, further comprising the step of monitoring the ventricular rate of the patient'"'"'s heart, and comparing the monitored rate to a threshold rate to determine whether the threshold rate is exceeded by the monitored rate, and if the threshold rate is exceeded then delivering a cardiac therapy electrical signal to the heart.

32. The method of claim 29 in which the step including delivery of cardiac therapy comprises delivery of at least one signal having a voltage greater than a normal pacing voltage so that the ventricular rate is modified to be less than the initial monitored rate after delivery of the cardiac therapy electrical signal.