LEADLESS PACEMAKER SYSTEM

• US 20140121719A1
• Filed: 10/31/2012
• Published: 05/01/2014
• Est. Priority Date: 10/31/2012
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Bonner, Matthew D., Greenhut, Saul E., Sheldon, Todd J., Demmer, Wade M.
• Granted Patent: US 8,923,963 B2
• Time in Patent Office: Days
• US Class Current: 607/18
• CPC Class Codes: A61N 1/0573 chacterised by means penetrating the heart tissue, e.g. helix needle or hook
• CPC Class Codes: A61N 1/36578 controlled by mechanical motion of the heart wall, e.g. measured by an accelerometer or microphone
• CPC Class Codes: A61N 1/3682 with a variable atrioventricular delay
• CPC Class Codes: A61N 1/3756 Casings with electrodes thereon, e.g. leadless stimulators
• CPC Class Codes: A61N 1/3987 characterised by the timing or triggering of the shock

Abstract

A device includes a signal generator module, a processing module, and a housing. The signal generator module is configured to deliver pacing pulses to an atrium. The processing module is configured to detect a ventricular activation event and determine a length of an interval between the ventricular activation event and a previous atrial event that preceded the ventricular activation event. The processing module is further configured to schedule a time at which to deliver a pacing pulse to the atrium based on the length of the interval and control the signal generator module to deliver the pacing pulse at the scheduled time. The housing is configured for implantation within the atrium. The housing encloses the stimulation generator and the processing module.

Claims

1. A device comprising:

a signal generator module configured to deliver pacing pulses to an atrium;

a processing module configured to;

detect a ventricular activation event;

determine a length of an interval between the ventricular activation event and a previous atrial event that preceded the ventricular activation event;

schedule a time at which to deliver a pacing pulse to the atrium based on the length of the interval; and

control the signal generator module to deliver the pacing pulse at the scheduled time; and

a housing configured for implantation within the atrium, wherein the housing encloses the stimulation generator and the processing module.

2. The device of claim 1, further comprising a sensing module configured to sense ventricular electrical activity, wherein the processing module is configured to detect the ventricular activation event by detecting the ventricular electrical activity.

3. The device of claim 2, wherein the ventricular electrical activity is a far-field R-wave.

4. The device of claim 3, wherein the processing module is configured to:

detect the ventricular activation event by detecting a far-field R-wave (FFRW);

determine the length of the interval between the ventricular activation event and the previous atrial event by determining a length of an interval between the detected FFRW and the previous atrial event; and

schedule the time at which to deliver the pacing pulse to the atrium based on the length of the interval between the detected FFRW and the previous atrial event.

5. The device of claim 1, further comprising a sensor that generates signals that indicate mechanical cardiac characteristics, wherein the processing module is configured to detect contraction of a ventricle based on the generated signals.

6. The device of claim 5, wherein the mechanical cardiac characteristics include heart sounds.

7. The device of claim 6, wherein the processing module is configured to:

detect the ventricular activation event by detecting an S1 heart sound;

determine the length of the interval between the ventricular activation event and the previous atrial event by determining a length of an interval between the detected S1 heart sound and the previous atrial event; and

schedule the time at which to deliver the pacing pulse to the atrium based on the length of the interval between the detected S1 heart sound and the previous atrial event.

8. The device of claim 1, further comprising a memory that stores a baseline atrioventricular (AV) value that is an expected value of the interval between the ventricular activation event and the previous atrial event during normal AV conduction of the heart.

9. The device of claim 8, wherein the processing module is configured to:

compare the determined length of the interval to the baseline AV value; and

schedule the time at which to deliver the pacing pulse to the atrium based on the comparison.

10. The device of claim 9, wherein the processing module is configured to:

identify the interval as having one of a normal duration, a short duration, or a long duration based on the comparison; and

schedule the time at which to deliver the pacing pulse to the atrium based on whether the interval is identified as having a normal duration, a short duration, or a long duration.

11. The device of claim 8, wherein the processing module is configured to:

compare the determined length of the interval to the baseline AV value;

identify the interval as having a normal duration when the determined length of the interval is approximately equal to the baseline AV value;

identify the interval as having a short duration when the determined length of the interval is less than the baseline AV value by a threshold amount; and

schedule the time at which to deliver the pacing pulse to the atrium based on whether the interval is identified as having the normal duration or the short duration.

12. The device of claim 8, wherein the processing module is configured to:

compare the determined length of the interval to the baseline AV value;

identify the interval as having a normal duration when the determined length of the interval is approximately equal to the baseline AV value;

identify the interval as having a long duration when the determined length of the interval is greater than the baseline AV value by a threshold amount; and

schedule the time at which to deliver the pacing pulse to the atrium based on whether the interval is identified as having the normal duration or the long duration.

13. The device of claim 1, wherein the processing module is configured to determine that the ventricular activation event went undetected, and wherein the processing module is configured to schedule a pacing pulse based on the determination that the ventricular activation event went undetected.

14. The device of claim 1, wherein the processing module is configured to determine when multiple ventricular activation events have occurred after the previous atrial event but before the scheduled time at which the pacing pulse is to be delivered, and wherein the processing module is configured to schedule a new time at which to deliver a pacing pulse to the atrium based on the determination that multiple ventricular activation events have occurred.

15. A method comprising:

detecting a ventricular activation event using an atrial pacing device configured for implantation within an atrium;

determining a length of an interval between the ventricular activation event and a previous atrial event that preceded the ventricular activation event;

scheduling a time at which to deliver a pacing pulse to the atrium based on the length of the interval; and

delivering the pacing pulse at the scheduled time.

16. The method of claim 15, further comprising:

sensing ventricular electrical activity; and

detecting the ventricular activation event by detecting the ventricular electrical activity.

17. A device comprising:

a signal generator module configured to deliver pacing pulses to an atrium;

a processing module configured to;

detect a first ventricular activation event;

detect a second ventricular activation event subsequent to the first ventricular activation event;

determine a length of an interval between the first and second ventricular activation events;

schedule a time at which to deliver a pacing pulse to the atrium based on the length of the interval; and

control the signal generator module to deliver the pacing pulse at the scheduled time; and

a housing configured for implantation within the atrium, wherein the housing encloses the stimulation generator and the processing module.

18. The device of claim 17, further comprising a memory that stores a baseline ventricular interval value that is an expected value of the interval between the first and second ventricular activation events during normal AV conduction of the heart.

19. The device of claim 18, wherein the processing module is configured to:

compare the determined length of the interval to the baseline ventricular interval value; and

schedule the time at which to deliver the pacing pulse to the atrium based on the comparison.

20. The device of claim 19, wherein the processing module is configured to:

identify the interval as having one of a normal duration, a short duration, or a long duration based on the comparison; and

schedule the time at which to deliver the pacing pulse to the atrium based on whether the interval is identified as having a normal duration, a short duration, or a long duration.