Automatic commutations of AAI/DDD mode in the presence of paroxystic AVB in an active implantable medical device, in particular a cardiac pacemaker

• US 20050143780A1
• Filed: 12/22/2004
• Published: 06/30/2005
• Est. Priority Date: 12/29/2003
• Status: Active Grant

• Current Assignee: Ela Medical S.A. (LivaNova Plc)
• Original Assignee: Ela Medical S.A. (LivaNova Plc)
• Inventors: Amblard, Amel, Henry, Christine, Limousin, Marcel
• Granted Patent: US 7,366,566 B2
• Time in Patent Office: Days
• US Class Current: 607/9
• CPC Class Codes: A61N 1/365 controlled by a physiological parameter, e.g. heart potential evoked response A61N1/371
• CPC Class Codes: A61N 1/368 comprising more than one electrode co-operating with different heart regions A61N1/3622, A61N1/3627 take precedence

Abstract

A device including circuits able to control the switching of a AAI mode in a DDD mode, and conversely the return of DDD mode to AAI mode, according to predetermined criteria of detection of atrio-ventricular block (AVB) of the first, second, or third degree and of ventricular pause. The device includes moreover circuits for detecting state, able to diagnose at least a specific temporary state of the patient, in particular a state of effort or sleep, and the circuits for mode switching operate in response to these circuits for detecting state to modify selectively, for the length of time when the aforementioned state is diagnosed, the criteria of switching from AAI mode towards DDD mode and/or the criteria of return to AAI mode, and/or the criteria of final commutation in DDD mode.

Claims

1. An active implantable medical device comprising:

means for detecting spontaneous atrial and ventricular events;

means for ventricular and atrial stimulation;

means able to operate the device in AAI mode with ventricular detection;

means able to operate the device in DDD mode; and

means for mode switching, able to control according to predetermined criteria the switching from AAI mode in DDD mode, and conversely the return from DDD mode to AAI mode;

the aforementioned predetermined criteria comprising;

criteria of switching from AAI mode towards DDD mode; and

criteria of return to AAI mode after switching towards DDD mode;

the aforementioned device being characterized in that it comprises;

state detecting means for diagnosing a temporary specific state of the patient carrying the device, including at least a phase of effort and/or a phase of sleep of the patient; and

said mode switching means is operating in response to the state detecting means, to modify the criteria of switching from AAI mode towards DDD mode for the length of time when said temporary specific state is diagnosed.

2. The device of claim 1, wherein the criteria of switching from AAI mode towards DDD mode are criteria able to control the switching when at least one of following conditions is fulfilled:

a) the number of atrial events followed by a ventricular detection occurring after a delay longer than a first reference duration exceeds a first predetermined number;

b) the number of atrial events not followed by a ventricular detection exceeds a second predetermined number among a third given number of consecutive atrial events;

c) the number of consecutive atrial events not followed by a ventricular detection exceeds a fourth predetermined number; and

d) the interval separating two ventricular events exceeds a second reference duration.

3. The device of claim 1, wherein the state detecting means are means able to diagnose a phase of cardiac decompensation of the patient.

4. The device of claim 1, wherein the state detecting means is able to diagnose moreover a phase of arrhythmia of the patient.

5. The device of claim 4, wherein the state detecting means are means able to diagnose a phase of suspicion of disorder of the atrial rate of the patient.

6. The device of claim 2, wherein the mode switching means is able to suspend, for a length of time at least equal to a duration of the phase of suspicion of disorder of the atrial rate of the patient, the checking of the conditions a) to c) of the criteria of switching from AAI mode towards the DDD mode, while maintaining the checking of the condition d).

7. The device of claim 2, wherein the mode switching means include a grid of counters assigned respectively to the conditions a) to d) of the criteria of switching from AAI mode towards DDD mode and to the types of states likely to be diagnosed, the corresponding counter being incremented when the respective condition is fulfilled and when the type of respective state is detected.

8. The device of claim 7, wherein the mode switching means further comprises a grid of thresholds homologous with the grid of counters, each threshold being programmable, and are able to force the switching from AAI mode towards DDD mode when one at least of the thresholds is reached by the corresponding counter.

9. The device of claim 1, wherein the means for mode switching are means operating in response to the state detecting means to modify the criteria of return to AAI mode after switching towards DDD mode during the time when a phase of effort or sleep is diagnosed.

10. The device of claim 9, wherein the mode switching means is operating in response to the means for detecting state to temporarily suspend any return to AAI mode after switching towards DDD mode during the time when a phase of effort or sleep is diagnosed.

11. The device of claim 9, wherein the mode switching means is operating in response to the means for detecting state to temporarily modify in a restrictive direction the criteria of return to AAI mode after switching towards DDD mode during the time when the phase of effort or sleep is diagnosed.

12. The device of claim 11, wherein the mode switching means is operating in response to the means for detecting state to control without delay the return to AAI mode after switching towards DDD mode after the end of the phase of effort or sleep.

13. The device of claim 11, wherein the mode switching means is operating in response to the means for detecting state to temporarily modify in an extensive direction the criteria of return to AAI mode after switching towards DDD mode after the end of the phase of effort or sleep.

14. The device of claim 1, wherein the predetermined criteria also comprise:

criteria of durable commutation to DDD mode; and

the mode switching means further comprises means of durable commutation, able to inhibit the return of DDD mode to AAI mode and to force the operating mode to DDD mode in function of the aforesaid criteria of durable commutation.

15. The device of claim 2, wherein means of durable commutation comprise counters incremented selectively according to the conditions a) to d) of the criteria of switching from AAI mode towards DDD mode when the respective condition is fulfilled, and the means to inhibit the return of DDD mode to AAI mode and to force the operating mode to DDD mode when the counters reach a predetermined configuration of counting.

16. The device of claim 15, wherein the means of durable commutation are able to inhibit the incrementing of the counters when one of the conditions a) to c) is fulfilled while authorizing the incrementing when the condition d) is fulfilled, in the event of commutation consecutive to a diagnosis of phase of effort or sleep.

17. The device of claim 15, wherein the means of durable commutation are able to inhibit the incrementing of the counters in the event of the occurrence of a commutation separated from the preceding commutation by a number of cycles in AAI mode lower than a fifth predetermined number.

18. The device of claim 14, wherein the means of durable commutation are able to inhibit the return of DDD mode to AAI mode and to force the operating mode to DDD mode when the number of commutations of AAI mode towards DDD mode is higher than a sixth number predetermined over a first predetermined temporal period.

19. The device of claim 14, wherein the means of durable commutation are able to inhibit the return of DDD mode to AAI mode and to force the operating mode to DDD mode when the percentage of ventricular events stimulated over a second predetermined temporal period is higher than a first predetermined threshold.

20. The device of claim 14, wherein the means of durable commutation further comprises means for controlling the return to the operating mode in AAI mode at the end of each phase of sleep.

21. The device of claim 15, wherein the means of durable commutation further comprises means for reinitialing the counters at the end of each phase of sleep.

22. The device of claim 14, wherein the predetermined criteria further comprise:

criteria of final commutation in DDD mode; and

the mode switching means further comprises means for final commutation, able to prohibit the return from DDD mode to AAI mode and to impose an operating DDD mode until reprogramming of the device, as a function of the criteria of final commutation.

23. The device of claim 22, wherein the means for final commutation are able to prohibit the return from DDD mode to AAI mode and to impose an operating DDD mode until reprogramming of the device when the number of durable commutations of AAI mode towards DDD mode is higher than a seventh predetermined number over a third predetermined temporal period.

24. The device of claim 22, wherein the means for final commutation are able to prohibit the return of DDD mode to AAI mode and to impose an operating DDD mode until reprogramming of the device when the percentage of ventricular events stimulated over a fourth predetermined temporal period is greater than a second predetermined threshold.

25. The device of claim 2, wherein the mode switching means reduces the first duration of reference during the time when a phase of effort is diagnosed.

26. The device of claim 25, wherein the mode switching means reduces the first duration of reference to a value which is an inverse function of the frequency of stimulation.

27. The device of claim 26, wherein the inverse function is a decreasing monotonic function from the base frequency of stimulation until the maximum frequency of stimulation.

28. The device of claim 26, wherein the inverse function is a decreasing monotonic function from a low frequency, higher than the base frequency of stimulation, to a high frequency, higher than the maximum frequency of stimulation, and a constant function below the base frequency of stimulation and above the maximum frequency of stimulation.

29. The device of claim 1, further comprising means for differentiated recording of cardiac data, able to memorize specifically predetermined certain data during time when the specific, temporary, state is diagnosed.

30. The device of claim 29, wherein the predetermined data memorized by the means of differentiated recording include the values of the durations of atrio-ventricular conduction.

31. The device of claim 29, wherein the predetermined data memorized by the means of differentiated recording include the duration of episodes during which commutations follow one another separated from each other by a number of cycles in AAI mode lower than a fifth predetermined number.