Leadless cardiac pacemaker system with conductive communication

• US 20070088397A1
• Filed: 10/13/2006
• Published: 04/19/2007
• Est. Priority Date: 10/14/2005
• Status: Active Grant

• Current Assignee: Pacesetter Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Pacesetter Incorporated (Abbott Laboratories Incorporated)
• Inventors: Jacobson, Peter
• Granted Patent: US 9,216,298 B2
• Time in Patent Office: Days
• US Class Current: 607/9
• CPC Class Codes: A61M 25/0662 Guide tubes
• CPC Class Codes: A61N 1/056 Transvascular endocardial electrode systems
• CPC Class Codes: A61N 1/0573 chacterised by means penetrating the heart tissue, e.g. helix needle or hook
• CPC Class Codes: A61N 1/0587 Epicardial electrode systems; Endocardial electrodes piercing the pericardium
• CPC Class Codes: A61N 1/059 Anchoring means
• CPC Class Codes: A61N 1/3621 for treating or preventing abnormally high heart rate
• CPC Class Codes: A61N 1/3627 for treating a mechanical deficiency of the heart, e.g. congestive heart failure or cardiomyopathy
• CPC Class Codes: A61N 1/36514 controlled by a physiological quantity other than heart potential, e.g. blood pressure controlled by two or more physical parameters A61N1/36585
• CPC Class Codes: A61N 1/36542 controlled by body motion, e.g. acceleration
• CPC Class Codes: A61N 1/368 comprising more than one electrode co-operating with different heart regions A61N1/3622, A61N1/3627 take precedence
• CPC Class Codes: A61N 1/3684 for stimulating the heart at multiple sites of the ventricle or the atrium
• CPC Class Codes: A61N 1/36842 Multi-site stimulation in the same chamber
• CPC Class Codes: A61N 1/3704 Circuits specially adapted therefor, e.g. for sensitivity control
• CPC Class Codes: A61N 1/3706 Pacemaker parameters stimulation threshold A61N1/371
• CPC Class Codes: A61N 1/3708 for power depletion
• CPC Class Codes: A61N 1/372 Arrangements in connection with the implantation of stimulators
• CPC Class Codes: A61N 1/37205 Microstimulators, e.g. implantable through a cannula
• CPC Class Codes: A61N 1/37217 characterised by the communication link, e.g. acoustic or tactile
• CPC Class Codes: A61N 1/37252 Details of algorithms or data aspects of communication system, e.g. handshaking, transmitting specific data or segmenting data
• CPC Class Codes: A61N 1/3727 characterised by the modulation technique
• CPC Class Codes: A61N 1/37288 : Communication to several implantable medical devices within one patient
• CPC Class Codes: A61N 1/37512 : Pacemakers
• CPC Class Codes: A61N 1/37518 : Anchoring of the implants, e.g. fixation
• CPC Class Codes: A61N 1/3756 : Casings with electrodes thereon, e.g. leadless stimulators
• CPC Class Codes: A61N 1/3925 : Monitoring; Protecting
• CPC Class Codes: A61N 1/3956 : Implantable devices for applying electric shocks to the heart, e.g. for cardioversion
• CPC Class Codes: A61N 1/39622 : Pacing therapy
• CPC Class Codes: A61N 2001/058 : Fixing tools
• CPC Class Codes: H04B 13/005 : Transmission systems in which the medium consists of the human body

Abstract

A cardiac pacing system comprises multiple leadless cardiac pacemakers configured for implantation in electrical contact with a cardiac chamber and configured for multi-chamber cardiac pacing. The individual leadless cardiac pacemakers comprise at least two leadless electrodes configured for delivering cardiac pacing pulses, sensing evoked and/or natural cardiac electrical signals, and communicating bidirectionally among the leadless cardiac pacemaker plurality.

Claims

1. A cardiac pacing system comprising:

a plurality of leadless cardiac pacemakers individually configured for implantation in electrical contact with a cardiac chamber and configured in combination for multi-chamber cardiac pacing, the leadless cardiac pacemaker plurality individually comprising at least two leadless electrodes configured for delivering cardiac pacing pulses, sensing evoked and/or natural cardiac electrical signals, and bidirectionally communicating among the leadless cardiac pacemaker plurality.

2. The system according to claim 1 further comprising:

individual pacemakers of the leadless cardiac pacemaker plurality configured to intercommunicate and to communicate with a non-implanted programmer via the at least two electrodes that are also used for delivering pacing pulses, the individual pacemakers configured for antenna-less and telemetry coil-less communication.

3. The system according to claim 1 further comprising:

individual pacemakers of the leadless cardiac pacemaker plurality configured to intercommunicate with one or more other leadless cardiac pacemakers and optionally a non-implanted programmer via communication that has transmitting communication power requirements essentially met by power consumed in cardiac pacing.

4. A system according to claim 1 further comprising:

individual pacemakers of the leadless cardiac pacemaker plurality comprising;

a hermetic housing configured for placement on or attachment to the inside or outside of a cardiac chamber; and

the at least two leadless electrodes proximal to the housing configured for bidirectional communication with at least one other device within or outside the body.

5. The system according to claim 1 further comprising:

the at least two leadless electrodes configured to communicate bidirectionally among the leadless cardiac pacemaker plurality to coordinate pacing pulse delivery using messages that identify an event at an individual pacemaker originating the message and pacemakers receiving the message react as directed by the message depending on the message origin.

6. The system according to claim 1 further comprising:

the at least two leadless electrodes configured to communicate bidirectionally among the leadless cardiac pacemaker plurality and transmit data including designated codes for events detected or created by an individual pacemaker, the individual pacemakers configured to issue a unique code corresponding to an event type and a location of the individual pacemaker.

7. The system according to claim 1 further comprising:

individual pacemakers of the leadless cardiac pacemaker plurality configured to deliver a coded pacing pulse with a code assigned according to pacemaker location and configured to transmit a message to at least one pacemaker of the leadless cardiac pacemaker plurality via the coded pacing pulse wherein the code identifies the individual pacemaker originating an event, the at least one pacemaker receiving the message being adapted to respond to the message in a predetermined manner depending on type and location of the event.

8. The system according to claim 1 further comprising:

individual pacemakers of the leadless cardiac pacemaker plurality configured to communicate to at least one pacemaker of the leadless cardiac pacemaker plurality occurrence of a sensed heartbeat at the individual pacemaker location via generation of a coded pacing pulse triggered by the sensed heartbeat in a natural refractory period following the sensed heartbeat.

9. The system according to claim 1 further comprising:

the plurality of leadless cardiac pacemakers configured for co-implantation in a single patient and multiple-chamber pacing, the bidirectional communication among the leadless cardiac pacemaker plurality adapted to communicate notification of a sensed heartbeat or delivered pacing pulse event and encoding type and location of the event to at least one pacemaker of the leadless cardiac pacemaker plurality, the at least one pacemaker that receives the communication adapted to decode the information and respond depending on location of the receiving pacemaker and predetermined system functionality.

10. The system according to claim 1 further comprising:

the leadless cardiac pacemaker plurality comprising an atrial leadless cardiac pacemaker implanted in electrical contact to an atrial cardiac chamber, the atrial leadless cardiac pacemaker configured to;

wait for an earliest occurring event of a plurality of events comprising a sensed atrial heartbeat, a communication of an event sensed on the at least two leadless electrodes encoding a pacing pulse marking a heartbeat at a ventricular leadless cardiac pacemaker, or timeout of an escape interval;

respond to the sensed atrial heartbeat by generating an atrial pacing pulse that signals to at least one pacemaker of the leadless cardiac pacemaker plurality that an atrial heartbeat has occurred and that encodes the atrial pacing pulse with a code signifying an atrial location and a sensed event type;

time a predetermined atrial-to-atrial (AA) escape interval; and

respond to timeout of an escape interval by delivering an atrial pacing pulse, causing an atrial heartbeat, the atrial pacing pulse encoding paced type and atrial location of an atrial heartbeat event.

11. The system according to claim 10 further comprising:

the atrial leadless cardiac pacemaker configured to time an atrial-to-atrial (AA) escape interval after generating an atrial pacing pulse whether triggered by atrial sensing or delivered in response to timeout of an escape interval.

12. The system according to claim 10 further comprising:

the atrial leadless cardiac pacemaker configured to;

detect a signal originating from a co-implanted ventricular leadless cardiac pacemaker;

examine an elapsed amount of the atrial-to-atrial (AA) escape interval since a most recent atrial heartbeat;

determine whether the signal originating from the co-implanted ventricular leadless cardiac pacemaker is premature;

in absence of a premature signal, wait for an event with no effect on atrial pacing;

in presence of a premature signal, restart a ventricle-to-atrial (VA) escape interval that is shorter than the atrial-to-atrial (AA) escape interval and representative of a typical time from a ventricular beat to a next atrial beat in sinus rhythm; and

respond to timeout of the VA escape interval or the AA escape interval by delivering an atrial pacing pulse, causing an atrial heartbeat, the atrial pacing pulse encoding paced type and atrial location of an atrial heartbeat event, and starting an AA escape interval and returning to a wait state.

13. The system according to claim 12 further comprising:

the atrial leadless cardiac pacemaker further configured to;

time a prolonged post-ventricular atrial refractory period (PVARP) after recycling in presence of the premature signal whereby pacemaker-mediated tachycardia is prevented.

14. The system according to claim 1 further comprising:

the leadless cardiac pacemaker plurality comprising a right-ventricular leadless cardiac pacemaker implanted in electrical contact to a right-ventricular cardiac chamber, the right-ventricular leadless cardiac pacemaker configured to;

wait for an earliest occurring event of a plurality of events comprising a sensed right-ventricular heartbeat, a sensed communication of a pacing pulse marking a heartbeat at an atrial leadless cardiac pacemaker, and timeout of an escape interval;

respond to the sensed right-ventricular heartbeat by generating a right-ventricular pacing pulse that signals to at least one pacemaker of the leadless cardiac pacemaker plurality that a right-ventricular heartbeat has occurred and that encodes the right-ventricular pacing pulse with a code signifying a right-ventricular location and a sensed event type;

restart a predetermined right ventricular-to-right ventricular (VV) escape interval after delivering a ventricular pacing pulse after either an atrial ventricular (AV) delay, a ventricular to ventricular (VV) delay, or a ventricular sensed event; and

respond to timeout of an escape interval by delivering a right ventricular pacing pulse, causing a right ventricular heartbeat, the right ventricular pacing pulse encoding paced type and right-ventricular location of a right ventricular heartbeat event.

15. The system according to claim 14 further comprising:

the right-ventricular leadless cardiac pacemaker configured to;

detect a signal originating from a co-implanted atrial leadless cardiac pacemaker;

examine an elapsed amount of the ventricular-to-ventricular (VV) escape interval since a most recent right-ventricular heartbeat;

determine whether the signal originating from the co-implanted atrial leadless cardiac pacemaker is premature;

in presence of a premature signal, wait for an event with no effect on ventricular pacing;

in absence of a premature signal, start a right atrium to right ventricular (AV) escape interval that is representative of a typical time from an atrial beat to a right-ventricular beat in sinus rhythm; and

respond to timeout of the VV escape interval or the AV escape interval by delivering a right ventricular pacing pulse, causing a right ventricular heartbeat, the right ventricular pacing pulse encoding paced type and right-ventricular location of a right ventricular heartbeat event, and starting a ventricular-to-ventricular (VV) escape interval and returning to a wait state.

16. The system according to claim 14 further comprising:

the right-ventricular leadless cardiac pacemaker configured to;

set the ventricular-to-ventricular (VV) escape interval longer than a predetermined atrial-to-atrial (AA) escape interval to enable backup ventricular pacing at a low rate corresponding to the VV escape interval in case of failure of a triggered signal from a co-implanted atrial leadless cardiac pacemaker.

17. The system according to claim 1 further comprising:

the leadless cardiac pacemaker plurality comprising a left-ventricular leadless cardiac pacemaker implanted in electrical contact to a left-ventricular cardiac chamber, the left-ventricular leadless cardiac pacemaker configured to;

wait at the left-ventricular leadless cardiac pacemaker for an earliest occurring event of a plurality of events comprising a sensed communication of a pacing pulse marking a heartbeat at an atrial leadless cardiac pacemaker, and timeout of a left ventricular escape interval; and

respond to timeout of the left ventricular escape interval by delivering a left ventricular pacing pulse, causing a left ventricular heartbeat, the left ventricular pacing pulse encoding type and location of a left ventricular heartbeat event.

18. The system according to claim 17 further comprising:

the left-ventricular leadless cardiac pacemaker configured to;

detect a signal originating from a co-implanted atrial leadless cardiac pacemaker;

examine an elapsed amount of the left ventricular escape interval since a most recent left-ventricular heartbeat;

determine whether the signal originating from the co-implanted atrial leadless cardiac pacemaker is premature;

in presence of a premature signal, wait for an event with no effect on ventricular pacing;

in absence of a premature signal, start a left atrium to left ventricular (AV) escape interval that is representative of a typical time from an atrial beat to a left ventricular beat in sinus rhythm; and

respond to timeout of the AV escape interval by delivering a left ventricular pacing pulse, causing a left ventricular heartbeat, the left ventricular pacing pulse encoding paced type and left ventricular location of a left ventricular heartbeat event, and starting a ventricular-to-ventricular (VV) escape interval and returning to a wait state.

19. The system according to claim 1 further comprising:

a controller coupled to the at least two electrodes adapted to examine output pulse duration from the at least one pacemaker of the leadless cardiac pacemaker plurality for usage as a signature for determining triggering information validity and, for a signature arriving within predetermined limits, activating delivery of a pacing pulse following a predetermined delay of zero or more milliseconds, the predetermined delay being determined from a method in a group consisting of preset at manufacture, programmed via an external programmer, and adaptively monitoring and conforming to duration of a triggering signal.

20. The system according to claim 1 further comprising:

a controller coupled to the at least two electrodes adapted to examine output pulse waveform from the at least one pacemaker of the leadless cardiac pacemaker plurality for usage as a signature for determining triggering information validity and, for a signature arriving within predetermined limits, activating delivery of a pacing pulse following a predetermined delay of zero or more milliseconds.

21. The system according to claim 1 further comprising:

individual pacemakers of the leadless cardiac pacemaker plurality configured for operation in a particular location and a particular functionality at manufacture and/or at programming by an external programmer.

22. The system according to claim 1 further comprising:

the leadless cardiac pacemaker plurality comprising a right ventricular leadless cardiac pacemaker and a left ventricular leadless cardiac pacemaker configured to operate with atrio-ventricular (AV) delays whereby a left ventricular pacing pulse can be delivered before, after, or substantially simultaneously with a right ventricular pacing pulse.

23. The system according to claim 1 further comprising:

the leadless cardiac pacemaker plurality configured for multi-site pacing that synchronizes depolarization for tachyarrhythmia prevention.

24. The system according to claim 1 further comprising:

the at least two leadless electrodes configured to communicate bidirectionally among the leadless cardiac pacemaker plurality and transmit data including designated codes for events detected or created by an individual pacemaker, the codes encoding information using pacing pulse width.

25. The system according to claim 1 further comprising:

the at least two leadless electrodes configured to communicate bidirectionally among the leadless cardiac pacemaker plurality and transmit data including designated codes for events detected or created by an individual pacemaker, the codes encoding information using binary-coded notches in a pacing pulse.

26. The system according to claim 1 further comprising:

a receiving amplifier/filter adapted for multiple controllable gain settings; and

a processor configured to control gain setting for the receiving amplifier/filter, invoking a low-gain setting for normal operation and detecting presence of a cardiac pacing pulse, and invoking a high-gain setting for detecting and decoding information encoded in the detected cardiac pacing pulse.

27. The system according to claim 1 further comprising:

the at least two leadless electrodes configured to communicate bidirectionally among the leadless cardiac pacemaker plurality and transmit data including designated codes for events detected or created by an individual pacemaker, the codes encoding information using modulation of off-time between pacing pulses.

28. The system according to claim 1 further comprising:

a tank capacitor coupled across a pair of the at least two leadless electrodes and adapted for charging and discharging wherein a pacing pulse is generated;

a charge pump circuit coupled to the tank capacitor and adapted for controlling charging of the tank capacitor; and

a processor configured to control recharging of the tank capacitor wherein recharging is discontinued when a battery terminal voltage falls below a predetermined value to ensure sufficient voltage for powering the leadless cardiac pacemaker.

29. A method for multi-chamber cardiac pacing comprising:

configuring a plurality of leadless cardiac pacemakers for implantation;

configuring an atrial leadless cardiac pacemaker of the leadless cardiac pacemaker plurality for implantation in electrical contact to an atrial cardiac chamber;

waiting for an earliest occurring event of a plurality of events comprising a sensed atrial heartbeat, a communication of an event sensed on the at least two leadless electrodes encoding a pacing pulse marking a heartbeat at a ventricular leadless cardiac pacemaker, or timeout of an atrial-to-atrial (AA) escape interval;

responding to the sensed atrial heartbeat by generating an atrial pacing pulse that signals to at least one pacemaker of the leadless cardiac pacemaker plurality that an atrial heartbeat has occurred and that encodes the atrial pacing pulse with a code signifying an atrial location and a sensed event type;

timing a predetermined length AA escape interval; and

responding to timeout of the AA escape interval by delivering an atrial pacing pulse, causing an atrial heartbeat, the atrial pacing pulse identifying paced type and/or atrial location of an atrial heartbeat event.

30. The method according to claim 29 further comprising:

encoding an atrial pacing pulse that identifies synchronous pacing triggered by an atrial sensed event with a first code; and

encoding an atrial pacing pulse that identifies atrial pacing following the AA escape interval with a second code distinct from the first code.

31. The method according to claim 29 further comprising:

delivering the atrial pacing pulse in absence of encoding whereby, for dual-chamber cardiac pacing, a pacing pulse that is not generated in a first cardiac pacemaker that senses the pacing pulse is necessarily generated in a second cardiac pacemaker.

32. The method according to claim 29 further comprising:

upon delivery of an atrial pacing pulse, timing an atrial-to-atrial (AA) escape interval.

33. The method according to claim 29 further comprising:

detecting at the atrial leadless cardiac pacemaker a signal originating from a co-implanted ventricular leadless cardiac pacemaker;

examining at the atrial leadless cardiac pacemaker an elapsed amount of the atrial-to-atrial (AA) escape interval since a most recent atrial heartbeat;

determining whether the signal originating from the co-implanted ventricular leadless cardiac pacemaker is premature;

in absence of a premature signal, wait for an event with no effect on atrial pacing;

in presence of a premature signal, restarting a ventricle-to-atrium (VA) escape interval that is shorter than the atrial-to-atrial (AA) escape interval and representative of a typical time from a ventricular beat to a next atrial beat in sinus rhythm; and

responding to timeout of the VA escape interval or the AA escape interval by delivering an atrial pacing pulse, causing an atrial heartbeat, the atrial pacing pulse encoding paced type and atrial location of an atrial heartbeat event, and restarting an atrial-to-atrial (AA) escape interval.

34. A method for multi-chamber cardiac pacing comprising:

configuring a plurality of leadless cardiac pacemakers for implantation;

configuring a right-ventricular leadless cardiac pacemaker of the leadless cardiac pacemaker plurality for implantation in electrical contact to a right-ventricular cardiac chamber;

waiting for an earliest occurring event of a plurality of events comprising a sensed right-ventricular heartbeat, a sensed communication of a pacing pulse marking a heartbeat at an atrial leadless cardiac pacemaker, and timeout of an escape interval;

responding to the sensed right-ventricular heartbeat by generating a right-ventricular pacing pulse that signals to at least one pacemaker of the leadless cardiac pacemaker plurality that a right-ventricular heartbeat has occurred and that encodes the right-ventricular pacing pulse with a code signifying a right-ventricular location and a sensed event type, restarting a predetermined ventricular-to-ventricular (VV) escape interval after ventricular pacing, and entering a wait state; and

responding to timeout of an escape interval by delivering a right ventricular pacing pulse, causing a right ventricular heartbeat, the right ventricular pacing pulse encoding paced type and right ventricular location of a right ventricular heartbeat event.

35. The method according to claim 34 further comprising:

encoding a right-ventricular pacing pulse that identifies synchronous pacing triggered by a right-ventricular sensed event with a first code; and

encoding a right-ventricular pacing pulse that identifies right-ventricular pacing following a ventricular-to-ventricular (VV) escape interval with a second code distinct from the first code.

36. The method according to claim 34 further comprising:

upon delivery of a right-ventricular pacing pulse, timing a ventricular-to-ventricular (VV) escape interval.

37. The method according to claim 34 further comprising:

detecting at the right-ventricular leadless cardiac pacemaker a signal originating from a co-implanted atrial leadless cardiac pacemaker;

examining at the right-ventricular leadless cardiac pacemaker an elapsed amount of the ventricular-to-ventricular (VV) escape interval since a most recent right-ventricular heartbeat;

determining whether the signal originating from the co-implanted atrial leadless cardiac pacemaker is premature;

in presence of a premature signal, waiting for an event with no effect on ventricular pacing;

for absence of a premature signal, starting a right atrium to right ventricular (AV) escape interval that is representative of a typical time from an atrial beat to a right-ventricular beat in sinus rhythm; and

responding to timeout of the AV escape interval or the VV escape interval by delivering a right ventricular pacing pulse, causing a right ventricular heartbeat, the right ventricular pacing pulse encoding paced type and right-ventricular location of a right ventricular heartbeat event.

38. A method for multi-chamber cardiac pacing comprising:

configuring a plurality of leadless cardiac pacemakers for implantation;

configuring a left-ventricular leadless cardiac pacemaker of the leadless cardiac pacemaker plurality for implantation in electrical contact to a left-ventricular cardiac chamber and for operation in cardiac resynchronization therapy (CRT-P);

waiting at the left-ventricular leadless cardiac pacemaker for an earliest occurring event of a plurality of events comprising a sensed communication of a pacing pulse marking a heartbeat at an atrial leadless cardiac pacemaker, and timeout of a left ventricular escape interval; and

responding to timeout of the left ventricular escape interval by delivering a left ventricular pacing pulse, causing a left ventricular heartbeat, the left ventricular pacing pulse encoding type and location of a left ventricular heartbeat event.

39. The method according to claim 38 further comprising:

detecting a signal originating from a co-implanted atrial leadless cardiac pacemaker;

examining an elapsed amount of the left ventricular escape interval since a most recent left-ventricular heartbeat;

determining whether the signal originating from the co-implanted atrial leadless cardiac pacemaker is premature;

in presence of a premature signal, waiting for an event with no effect on ventricular pacing;

in absence of a premature signal, starting a left atrium to left ventricular (AV) escape interval that is representative of a typical time from an atrial beat to a left ventricular beat in sinus rhythm; and

responding to timeout of the left ventricular escape interval or the AV escape interval by delivering a left ventricular pacing pulse, causing a left ventricular heartbeat, the left ventricular pacing pulse encoding paced type and left ventricular location of a left ventricular heartbeat event, and starting a ventricular-to-ventricular (VV) escape interval and returning to a wait state.

40. The method according to claim 38 further comprising:

configuring the left-ventricular leadless cardiac pacemaker for operation in cardiac resynchronization therapy (CRT-P).