Heart treatment equipment and method for preventing fatal arrhythmia

• US 20040215289A1
• Filed: 12/03/2003
• Published: 10/28/2004
• Est. Priority Date: 12/04/2002
• Status: Active Grant

• Current Assignee: Terumo Kabushiki Kaisha (Terumo Corporation)
• Original Assignee: Terumo Kabushiki Kaisha (Terumo Corporation)
• Inventors: Fukui, Yoshihito
• Granted Patent: US 7,142,917 B2
• Time in Patent Office: Days
• US Class Current: 607/48
• CPC Class Codes: A61B 5/7282 Event detection, e.g. detecting unique waveforms indicative of a medical condition A61B5/4094, A61B5/4818, A61B5/349, A61B5/0823 take precedence
• CPC Class Codes: A61N 1/36114 Cardiac control, e.g. by vagal stimulation stimulating the heart A61N1/362
• CPC Class Codes: A61N 1/365 controlled by a physiological parameter, e.g. heart potential evoked response A61N1/371

Abstract

In order to avoid a sudden cardiac death by a fatal arrhythmia, various living body information for generating a signal which shows a level of an autonomic tone is detected by a sensor or a VT/VF risk event is detected so as to control the stimulation of the vagus nerve or the nerve stimulation waveform. For this purpose, the parameter of the nerve stimulation signal is controlled according to a detection of the living body information represented by a QT interval which is measured by intracardiac information of the heart or a detection of a VT/VF risk event represented by a ventricular premature contraction which is picked up from spontaneous cardiac events.

Claims

1. A heart treatment equipment for treating a patient comprising:

a nerve stimulator for generating a nerve stimulating signal for stimulating a vagus nerve;

a sensor for sensing living body information of the patient; and

a controller connected to said nerve stimulator and said sensor,

wherein said controller controls said nerve stimulator in response to an output of said sensor.

2. A heart treatment equipment according to claim 1, wherein said controller includes a memory for storing a plurality of stimulation parameters of said nerve stimulating signal and selects at least one of said parameters from said memory in response to an output of said sensor.

3. A heart treatment equipment according to claim 2, wherein said parameters stored in said memory are a plurality of stored values with respect to at least one of a period between pulses, a pulse width, a number of pulses, a pulse current, a pulse voltage, a delay time, a rest time and a repetitive number or with respect to a multiple combination chosen from these.

4. A heart treatment equipment according to claim 1, wherein said sensor detects a ventricle contractility.

5. A heart treatment equipment according to claim 4, wherein the ventricle contractility is related to one of a QT interval, an intracardiac electrogram area, a pre-ejection period, a stroke volume and a ventricle pressure.

6. A heart treatment equipment according to claim 4, wherein said controller controls said nerve stimulator so as to stop the generation of said nerve stimulating signal when the ventricle contractility is out of a predetermined range.

7. A heart treatment equipment according to claim 1, wherein said sensor senses an activity.

8. A heart treatment equipment according to claim 1, wherein said sensor senses a respiration.

9. A heart treatment equipment according to claim 1, wherein said sensor senses a blood.

10. A heart treatment equipment according to claim 1, further comprising a heart stimulator for generating a heart stimulating pulse for stimulating the heart, wherein when the heart rate decreases below a predetermined rate, said heart stimulator stimulates the heart at said predetermined rate.

11. A heart treatment equipment comprising:

a nerve stimulator for generating a nerve stimulating signal for stimulating a vagus nerve;

a heart abnormal detector for detecting an abnormal condition of the heart; and

a controller for connecting said nerve stimulator and said heart stimulator,

wherein said controller controls said nerve stimulator in response to an output of said heart abnormal detector.

12. A heart treatment equipment according to claim 11, wherein said controller includes a memory for storing a plurality of stimulation parameters of said nerve stimulating signal and selects at least one of said parameters from said memory in response to an output of said heart abnormal detector.

13. A heart treatment equipment according to claim 11, further comprising a heart event detector for detecting a heart event, wherein said heart abnormal detector is a risk event detector connected to said heart risk event detector for detecting a tachycardia risk event.

14. A heart treatment equipment according to claim 12, wherein said parameters are a plurality of stored values with respect to at least one of a period between pulses, a pulse width, a number of pulses, a pulse current, a pulse voltage, a delay time, a rest time and a repetitive number or with respect to a multiple combination chosen from these.

15. A heart treatment equipment according to claim 13, wherein said risk event includes an increase of the heart rate.

16. A heart treatment equipment according to claim 13, wherein said risk event includes a premature contraction.

17. A heart treatment equipment according to claim 13, wherein said risk event includes an early afterdepolarization.

18. A heart treatment equipment according to claim 13, wherein said tachycardia risk event includes a delayed afterdepolarization.

19. A heart treatment equipment according to claim 13, further comprising a heart stimulator for generating a heart stimulating pulse for stimulating the heart, wherein when the heart rate decreases below a predetermined rate, said heart stimulator stimulates the heart at said predetermined rate.

20. A heart treating method comprising:

process for sensing living body information; and

process for stimulating a vagus nerve in accordance with a variable parameter suitable for said living body information in response to the sensed living body information.

21. A heart treating method according to claim 20, wherein said living body information is sensed information of a heart.

22. A heart treating method according to claim 20, wherein said living body information is sensed information of a signal relied upon an autonomic nerve activity.

23. A heart treating method according to claim 20, wherein said parameter is at least one of a period between pulses, a pulse width, a number of pulses, a pulse current, a pulse voltage, a delay time, a rest time and a repetitive number or is a multiple combination chosen from these.