Configurable switching mechanism for leadless pacemaker systems.

Abstract

The present invention relates to a system and method for replacing an implanted medical device (10; 20) with an implantable medical replacement device (30), in which a programming device (1) sends a command signal (S1) to the medical device (10; 20) to change the address of the medical device (10; 20) to a new address different from the address of the replacement device (30), allowing the programming device (1) to communicate independently with both the medical device (10; 20) and the replacement device (30).

Description

[Technical Field]

[0001] The present invention relates to programming devices, medical systems and methods. [Background technology]

[0002] When an ERI of a cardiac implant, such as a leadless cardiac pacemaker, is declared (where ERI represents the elective replacement interval, i.e., when the implant's battery is approaching a depleted state), the cardiac implant should be replaced immediately.

[0003] In particular, for pacemaker-dependent patients, the existing device (e.g., an implantable leadless pacemaker) must continue to function until a replacement device is activated.

[0004] In known lead-equipped pacemakers, replacement is accomplished by opening the pocket in which the pacemaker is located, quickly transferring the lead from the existing implant to the new implant, and then closing the pocket after removing the old implant. Because the endocardial ends of the leads remain unchanged, it can be assumed that if the new implant is programmed the same as the old implant, therapy should continue without interruption.

[0005] With leadless implants, there is no lead moving from one implant to another. The new implant must be implanted in an inactive state in the heart to avoid conflict with the old device. Unlike an unchanged lead, the electrode-tissue interface associated with the new leadless implant is untested at this point and may prove insufficient to deliver therapy. Testing of the new electrode placement must be coordinated with the old implant so that therapy is interrupted for a minimal amount of time if placement is insufficient. Once the new placement passes, the old implant must be deactivated in sync with activation of the new implant.

[0006] In particular, European Patent Application Publication No. 3082953 discloses an implantable medical device including a power manager configured to detect an end-of-life state of a power source and at least partially disable an operation circuit of the implantable medical device that can be embedded in a stop element in response to the detection of the end-of-life state.

[0007] Furthermore, U.S. Patent Application Publication No. 2012 / 0197332 discloses a first implantable medical device coupled to a first plurality of electrodes, the first implantable medical device configured to deliver therapeutic electrical stimulation to a patient via the first plurality of electrodes, and a second medical device coupled to a second plurality of electrodes, the second medical device configured to deliver therapeutic electrical stimulation to the patient via the second plurality of electrodes to suppress the delivery of therapeutic electrical stimulation by the first implantable medical device, adjust the therapeutic electrical stimulation delivered by the second implantable medical device according to a predetermined pattern, and provide an inactivation command to the first implantable medical device, wherein the first implantable medical device is inactivated in response to receiving the inactivation command.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Patent Document 2

Summary of the Invention

[0009] Based on the above, an object of the present invention is to provide a programming device, a medical system, and a method that enable safe and systematic replacement of an implantable medical device, particularly an implantable leadless cardiac pacemaker.

[0010] This object is solved by a system having the features of claim 1 and a method having the features of claim 13. Preferred embodiments of each aspect of the invention are described in the corresponding dependent claims and are described below.

[0011] According to claim 1, a programming device for replacing an implanted medical device with an implantable medical exchange device is disclosed. The programming device is configured to transmit a command signal wirelessly to the implanted medical device in order to change the address of the medical device to a new address different from the address of the exchange device, enabling independent communication of the programming device with both the medical device and the exchange device. In particular, the programming device can be a portable device (e.g., a handheld device), such as a smartphone or a dedicated remote control.

[0012] According to one embodiment, the programming device reversely transmits a command signal to the exchange device to change the address of the exchange device to one different from that related to the medical device. The additional broadcast command or a series of broadcasts and device-specific commands can advance the relay of the command signal to obtain address-specifying information from all medical devices (exchange or otherwise) accessible (directly or indirectly) by the programming device.

[0013] In particular, the implanted medical device includes a battery that discharges below a specific threshold, and thus needs to be replaced by the exchange device to ensure proper delivery of treatment to the patient.

[0014] In particular, according to one embodiment of the programming device, a communication protocol that enables configuring the address of the implanted medical device is implemented in the programming device. In particular, the command signal is responded to by the medical device (or the exchange device or other medical devices of the system) only when each command signal explicitly targets each medical device (i.e., each address).

[0015] Furthermore, according to one embodiment of the present invention, the address is an integer value stored in a medical device. When receiving a message, the medical device determines whether the address is known by comparing the stored integer value with the value in the address field of the received message. As a result, the medical device can determine whether to respond to the message.

[0016] In one embodiment, the address value commonly used for this address (distributed by the factory and used by active devices by convention) is known to the programming device. The programming device can send a command to the medical device to use this address to change its address so that multiple medical devices within a communication session can each have a session-specific address. The active implant in this scheme should end the session using the commonly used address stored as its device address.

[0017] In a preferred embodiment, the programming device polls the devices in its communication proximity to find the unique factory-assigned address of each device (which may be the serial number of the device). The programming device polls all devices using a broadcast address and uses some mechanism such as a time slot or a random delay to enable each device to return its unique identifier to the programming device. The programming device can then assign a unique session address to each medical device using commands that target each medical device based on its unique identifier. This session address then enables the programming device to send commands that identify the session address associated with the device to which the message is intended.

[0018] Furthermore, according to one embodiment of the programming device, the programming device includes a communication protocol implemented in the programming device, and the communication protocol includes a predefined broadcast address independent of their assigned addresses to which at least the medical device and the exchange device will respond. In particular, all devices of the system under consideration (e.g., embedded medical devices, exchange devices, especially further embedded medical devices) respond to command signals sent to the broadcast address by the programming device.

[0019] In particular, such broadcast commands can be used to trigger simultaneous actions in some of the plurality of devices. In particular, an embedded medical device can form part of a medical system that includes at least one further embedded medical device.

[0020] In particular, the medical device and the further medical device can each be formed by an implantable leadless cardiac pacemaker, one pacemaker can be implanted in the ventricle of the patient's heart, and the other pacemaker can be implanted in the atrium of the heart (see below). In particular, each implantable leadless cardiac pacemaker is understood to be a cardiac pacemaker that includes pacing electrodes disposed in the pacemaker housing, and the housing is configured to be fixed to the heart wall (e.g., in the atrium or ventricle). In particular, the housing surrounds the battery of the leadless cardiac pacemaker. Thus, in particular, the leadless cardiac pacemaker does not include an elongated electrode lead.

[0021] In particular, each leadless cardiac pacemaker can be configured to operate in an idle state in which each leadless cardiac pacemaker is configured to detect cardiac events but is prevented from applying pacing pulses to the heart.

[0022] Furthermore, in one embodiment, the programming device is configured to send a start command signal to the switching device to start the switching device to take the idle state. In particular, additional commands can be used to confirm that the detection is functioning properly. The additional commands can be sent by the programming device. According to one embodiment, the programming device is configured to send a command signal to the switching device to configure the switching device to the idle state.

[0023] Furthermore, according to one embodiment of the programming device, after starting the switching device to take the idle state, the programming device is configured to send an additional command signal to the switching device to apply a pacing pulse of a specific rate to the patient's heart to the implanted switching device during either 1.) a predetermined number of cardiac cycles (supporting a pacing capture test routine) or 2.) a fixed on state in which treatment is delivered until an active communication link failure or a system-configurable timeout occurs (preventing permanent programming of the switching device). The intention of these configurations is to evaluate the electrical interaction of the device / patient associated with the switching device, but to stabilize the output from the switching device only in a temporary form until it is known that such engagement is stable and reliable. Until such a state is known, the expiration of the pacing output from the switching device provides a fail-safe that depends on the output from the device intended to avoid the administration of permanent treatment from the switching device and to be replaced as a means for improving bradycardia (at least in the treatment modality).

[0024] Furthermore, in one embodiment, after transmitting the further command signal to the switching device, the programming device transmits a command to the device intended to be switched (i.e., the one with the newly assigned address), thereby effectively programming it into an out-of-the-way state. This out-of-the-way state uses a reduced therapeutic pacing rate (escape rhythm condition, i.e., almost unchanged from 40 ppm) to provide basic pacing assistance and is enhanced with the ability to stop the output from the device to be switched when detecting pacing output activity from the switching device. During active communication (e.g., a programming event), except for the receipt of an explicit command input (from the programming device) that would otherwise be done, (or before the expiration of any associated system-level timeout), the implant to be switched remains in this out-of-the-way state to provide therapeutic bradycardia management support. In contrast to the temporary output administered by the switching device, the device to be switched simply continues to pump blood to the patient's heart only as a backup and does not provide output in the presence of the output from the switching device. In response to the aforementioned fail-safe approach, the device to be switched experiences a link failure or an associated system-level timeout and restores its permanent programmed therapeutic output, forcing the system to return to the last known good pre-switch support state that is substantially harmless and uncontaminated.

[0025] Once a reliable executable pacing capture threshold is determined for the switching device, the system facilitates the cessation of the permanent therapeutic output from the switching device while also coordinating the permanent cessation of the device being switched. The recommended sequence for such a change favors the use of a permanent program write to the switching device (when the clinician has the opportunity to adjust the intended therapy before transmitting it to the implant), followed by a subsequent separate permanent program write to the device being switched that permanently deactivates it (rendering the device incommunicable). The system provides an appropriate clinician warning prior to this permanent deactivation step to represent an irreversible process. The net result of the procedure outlined above is to effect a permanent program therapy output from the switching device and a "bricking" of the device originally being switched for replacement such that it is precluded from any meaningful means of electrically interfering with the therapy output of the new switching device. (Note: In this description, executable detection and impedance conditions are also prioritized and assumed to have been determined for the switching device. This is not specified in the description as an intentional means of clarifying an important advantage of the invention.)

[0026] According to one embodiment of the proposed system, the programming device is configured to transmit a command signal to a new address of an implantable medical device after transmitting the command signal. The command signal can configure the implantable medical device to use a reduced therapy pacing rate and an ability to suppress the output from the device being switched when pacing output activity from the switching device is detected. The implantable medical device can maintain the state during active communication (or before the expiration of any associated system-level timeout), and avoid receiving an explicit command input (from the programming device) otherwise (to provide remedial temporary bradycardia management support).

[0027] For example, an implantable cardiac pacemaker can be programmed to monitor a unique detection signal over a period of time in each cardiac cycle. If sensing is not detected, the pacemaker applies a pacing stimulus. If an old implantable device exists, it is programmed to wait longer (before a pacing stimulus is applied) to detect sensing than a new implantable device does. If the old implantable device detects sensing, pacing is inhibited.

[0028] Preferably, according to one embodiment, the therapy is applied by an exchange device, while the therapy is disabled in the previous implantable device during active communication.

[0029] The implanted medical device can form part of a single-chamber therapy system from the device being exchanged to the exchange device, and the end result is that a single heart chamber is stimulated before the exchange and then the same heart chamber is stimulated, but using only the exchange device.

[0030] In particular, the programming device is configured to communicate with the medical device being exchanged (single implant) using an inductive coupling telemetry path. Further, the medical device is configured to detect when a command signal is directed by comparing the destination address in the command signal (or message) with an internally stored address, and the programming device is configured to transmit the command signal, which is interpreted by the medical device to change the address to a new address, to the medical device. In particular, the exchange device (e.g., an implantable leadless cardiac pacemaker) is implanted in the patient's heart. In particular, the programming device is configured to distinguish which of the two implants the destination address is addressed to using the destination address and communicate with both implants. The exchange device (new implant) has an address at factory shipment.

[0031] In particular, in a single implant system, the medical device can be an implantable leadless cardiac pacemaker, such as a VDD pacemaker implantable in the ventricle. This can be programmed by a programming device.

[0032] Furthermore, according to an alternative embodiment, the medical device forms part of a two-implant dual chamber therapy system, the two-implant system includes a further medical device, the medical device forms a master device, the further medical device forms a slave device, and the programming device is configured to transmit command signals to the slave device via the master device (e.g., the master device is configured to pass command signals from the programming device to the slave device).

[0033] Alternatively, the medical device can form part of a two-implant dual chamber therapy system, the two-implant dual chamber therapy system includes a further medical device, where the medical device forms a slave device, the further medical device forms a master device, and the programming device is configured to transmit respective command signals to the slave device via the master device (e.g., the master device is configured to pass command signals from the programming device to the slave device).

[0034] According to a further aspect of the invention, a medical system including a programming device according to the invention is disclosed, the system further including an implantable medical device to be replaced and / or an implantable medical exchange device for replacing the medical device.

[0035] In particular, according to one embodiment of the system, the programming device includes a communication protocol implemented in the programming device, the communication protocol including a predefined broadcast address independent of their assigned addresses to which at least the medical device and the exchange device will respond.

[0036] According to one embodiment of the present invention, the communication protocol is implemented in all devices within a system configured to communicate with at least one other device.

[0037] In particular, all devices of the system under consideration (e.g., implantable medical devices, exchange devices, in particular further implantable medical devices, see below) are configured to respond to a command signal transmitted to a broadcast address by a programming device.

[0038] According to one embodiment of the present system, the medical device is an implantable leadless cardiac pacemaker that can be implanted in a patient's heart, and the exchange device is also an implantable leadless cardiac pacemaker. The exchange device is configured to detect cardiac events but is configured to operate in an idle state where it is prevented from applying pacing pulses to the heart.

[0039] Furthermore, according to one embodiment of the system, the programming device is configured to send a start command signal to the exchange device, and the exchange device is configured to be started to take the idle state upon receiving the start command signal. As described above, additional commands can be used to confirm that the detection is functioning properly.

[0040] Furthermore, according to one embodiment of the system, after activating the exchange device to take the idle state, the programming device is configured to send a further command signal to the exchange device, and the implanted exchange device is configured to apply pacing pulses at a specific rate to the patient's heart for a predetermined number of cardiac cycles when it receives the further command signal.

[0041] Further, according to one embodiment of the system, after transmitting the additional command signal, the programming device is configured to transmit a command signal to the new address of the implanted medical device, and the implanted medical device is configured to suppress the application of pacing pulses of the implanted medical device to the patient's heart when detecting heart activity at a rate corresponding to or higher than the rate of the switching device for a predetermined number of cardiac cycles when receiving the interruption command signal.

[0042] According to one embodiment of the proposed system, the programming device transmits a permanent stop command signal to the new address of the implanted medical device when the user approves and / or confirms the feasible capture of the patient's heart from the switching device. In one embodiment, the permanent stop affects the implanted medical device such that it no longer provides detection, communication, or pacing output in order to avoid electrical interference with the treatment output from the switching device.

[0043] According to one embodiment, the programming device is configured to transmit a permanent stop command signal to the new address of the implanted medical device when the capture of the patient's heart is approved or confirmed by the switching device.

[0044] Further, according to one embodiment of the system, the programming device is configured to transmit a stop command signal to the new address of the implanted medical device when the capture of the patient's heart with respect to the pacing pulses applied by the switching device is detected by the implanted switching device, and the implanted medical device is configured to be stopped when receiving the stop command signal, particularly when active communication ends.

[0045] Furthermore, according to one embodiment of the system, the programming device is configured to send an activation command signal to the embedded switching device, particularly when the active communication has ended, and the switching device is configured to be activated when it receives the activation command signal. In particular, if any device (i.e., the medical device to be exchanged or the switching device) cannot confirm the stop / activation command, the programming device can be configured to retransmit each command signal before the communication ends.

[0046] According to one embodiment of the system, an (embedded) medical device (e.g., an implantable wireless cardiac pacemaker, see also above) forms the only implant of the system. In particular, in one embodiment of the system, the programming device is configured to communicate with the (single) medical device using an inductive coupling telemetry path. Furthermore, the medical device is configured to detect when a command signal is indicated by comparing the destination address in the command signal (or message) with an internally stored address, and the programming device is configured to send the command signal, which is interpreted by the medical device to change the address to a new address, to the medical device.

[0047] Furthermore, according to one embodiment of the system, the system includes additional implantable medical devices. Preferably, each of the medical devices is an implantable wireless cardiac pacemaker. In particular, in one embodiment, the system includes a wireless pacemaker in the right atrium and a wireless pacemaker in the right ventricle. Together, they can form a DDI or DDD pacemaker system. If the system includes two or more implantable medical devices, the programming device is configured to communicate directly only with one of them, a master device. The master device is configured to communicate with the other implantable medical devices, slave devices, to configure it. In a preferred embodiment, the programming device communicates with the master device using inductive communication.

[0048] Furthermore, according to one embodiment, the master device and the slave device are configured to communicate with each other using an independent communication system such as an impedance-based or ultrasonic-based physical network layer. In particular, in one embodiment of the system, each medical device can include a communication unit configured to generate messages in the form of ultrasonic signals. This means that the telemetry head (e.g., wand) of the programming device only needs to be placed in an optimal position to communicate with the master device and is not placed in a compromised position that would require both medical devices to be moved within range at the same time.

[0049] Furthermore, according to one embodiment of the system, one medical device forms the master device, another medical device forms the slave device, the programming device is configured to send command signals to the slave device via the master device, and the master device is configured to pass the command signals from the programming device to the slave device. In this embodiment, the master device is replaced by an exchange device.

[0050] According to an alternative embodiment of the system, the slave device will be replaced by an exchange device, i.e., one medical device forms the slave device, a further medical device forms the master device, the programming device is configured to send respective command signals to the slave device via the master device, and the master device is configured to pass the command signals from the programming device to the slave device.

[0051] Furthermore, according to yet another aspect of the present invention, a method for replacing an implanted medical device with an implantable medical exchange device is disclosed, in which a command signal is transmitted wirelessly using a programming device to the implanted medical device to change the address of the medical device to a new address different from the address of the exchange device in order to enable independent communication of the programming device with both the medical device and the exchange device. The exchange device is configured to detect cardiac events but is prevented from applying pacing pulses to the heart. To activate the exchange device to take an idle state, an activation command signal is transmitted by the programming device to the exchange device. After activating the exchange device to take the idle state, either 1.) a predetermined number of cardiac cycles (supporting a pacing capture test routine) or 2.) a fixed on-state condition of providing treatment until an active communication link failure or a system-configurable timeout occurs (preventing permanent programming of the exchange device). To cause the implanted exchange device to apply pacing pulses to the patient's heart, a further command signal is transmitted by the programming device to the exchange device. To drive in a temporary out-of-the-way state, a command signal is transmitted by the programming device to the new address of the implanted medical device. The implanted medical device performs a low-rate pacing (or a faster intrinsic rate) that is suppressed by the detection of pacing pulses related to the exchange device. When the clinician confirms that an executable pacing capture threshold is achieved at the implant site of the exchange device, an activation command signal is transmitted by the programming device to the implanted exchange medical device to activate the exchange device to start applying the configured permanent program treatment support, and a permanent stop command signal is transmitted by the programming device to the new address of the medical device.

[0052] The intention of this method is to evaluate the electrical interaction of the device / patient related to the replacement device, but to stabilize the output from the replacement device only in a temporary form until it is known that such engagement is stable and reliable. Until such a state is known, the expiration of the pacing output from the replacement device provides a fail-safe that depends on the output from a device intended to avoid the administration of permanent treatment from the replacement device and to be substituted (at least in the treatment modality) as a means for improving bradycardia. When firm capture is confirmed at the replacement device implantation site, the method stops the permanent treatment from the replacement device and permanently disables the device originally intended for replacement. Thus, this method transfers the treatment output to the replacement device when it is known to provide a means for viable support, and then "bricks" the device originally intended for replacement that could electrically interfere with the treatment output from the new device.

[0053] According to one embodiment of the method, the medical device is an implantable leadless cardiac pacemaker that can be implanted in a patient's heart, and the replacement device is also an implantable leadless cardiac pacemaker, and the replacement device is configured to operate in an idle state in which it is configured to detect cardiac events but is prevented from applying pacing pulses to the heart.

[0054] According to a further embodiment of the method, the implanted medical device can form part of a single implant treatment system when utilizing the concepts detailed within the present invention to transfer treatment from the device intended for replacement to the replacement device, and the end result is that a single cardiac chamber is stimulated prior to replacement and then the same cardiac chamber is stimulated, but simply using the replacement device. Preferably, the implant may be present in the patient, ventricle, atrium, or potentially other locations.

[0055] According to one aspect of the present invention, a system and method for automatically transferring a stimulation function from an implanted medical device to an implantable medical exchange device are proposed, and the transfer is assisted by a programming device. The present invention relates to the case where an exchange of an implanted medical device for an exchange device is necessary. The proposed system and method are particularly useful for patients who are pacemaker-dependent.

[0056] The proposed system and method include programming the implanted medical device and the exchange device, and the stimulation function is automatically switched from the implanted medical device to the implantable medical exchange device.

[0057] According to one example, both the implanted medical device and the implantable medical exchange device are implantable leadless pacemakers (hereinafter referred to as "implanted leadless pacemaker" and "exchange leadless pacemaker").

[0058] The procedure for replacing an old leadless pacemaker with a new one is completely different from the procedure for replacing a pacemaker with conventional leads. In the case of a conventional pacemaker, the intracardiac lead remains inside the patient, and only the device housing is replaced, whereby the old lead is reconnected to the new device housing. Once a leadless pacemaker needs to be replaced, a completely new leadless pacemaker is implanted while the old device remains inside the patient's body. In particular, in the case of a patient who is pacemaker-dependent, the treatment function needs to be guaranteed during the replacement procedure.

[0059] A solution to this problem is proposed in the form of an appropriate programming sequence controlled by a programming device for an implanted medical device ("implanted device") and an implantable medical exchange device ("exchange device").

[0060] One embodiment of the present invention is developed to query the implanted device and the replacement device after implantation of the replacement device while the implanted device is still active. The replacement device is first programmed to a temporary configuration suitable for the patient. Then, the programming configuration of the implanted device is adapted by the replacement device in the transfer procedure. In the case of the transfer procedure, the replacement device is first triggered to perform overdrive pacing to the tissue (for example, the stimulation rate of the replacement device is 5-10 bpm faster than the basic rate determined by the implanted device), and the implanted device is switched to suppress stimulation.

[0061] If successful, i.e., after performing the transfer procedure, the replacement device effectively stimulates the tissue, the temporary configuration of the replacement device is permanently set, the replacement device is configured to stimulate at the basic interval, and the stimulation of the implanted device is switched off.

[0062] According to one embodiment, for implantation of the replacement device before the stimulation configuration is performed by the programming device, the replacement device is set to a special mode in which the device is ready for use but the stimulation function and automatic implant detection are disabled.

[0063] Preferably, according to an aspect of the present invention, the programming device must be able to process two valid session keys (one from the implanted device and one from the replacement device simultaneously) in this procedure.

[0064] According to an embodiment, the procedure can be as follows. The programming device continuously queries both implants in an uninterrupted sequence. 1. Query command for the implanted device a. The replacement device does not respond to this command in special mode b. The programming device saves the complete program from the implanted device 2. A special query command for the replacement device ignored by the implanted device follows.

[0065] The programming device maintains communication connections to two implants.

[0066] According to one embodiment, when the stimulation function of the implanted device is suppressed, the programming device configures the implanted device into a temporary program. In the temporary program, the implanted device applies a stimulation pace at a rate 5 - 10 bpm faster than the basic interval until safe pacing is achieved. The frequency corresponding to the shortened interval is an appropriate overdrive pacing interval (ODSI) that enables the switching device to be programmed thereafter.

[0067] The programming device terminates the temporary overdrive pacing for the implanted device by incrementally extending the baseline interval until the implanted device is safely suppressed again.

[0068] When the implanted device is not suppressed, the ODSI is calculated as follows: the programmed basic rate of the implanted device + 10 bpm.

[0069] The programming device then starts an R-wave synchronized temporary program in the switching device (for the implanted device) using all the programming parameters of the implanted device, with the following exceptions. The basic rate is increased by the ODSI (compared to the basic interval of the implanted device) and thus functions as safe overdrive stimulation.

[0070] Thereby, the implanted device is immediately suppressed (if not already present), and the switching device takes over the stimulation. The programming device can start an automatic threshold test via the switching device, set the stimulation threshold, and complete the implant detection.

[0071] If no valid threshold is found, the programming device repeats the search. If the threshold test still fails, the programming device ends the temporary program in the switching device and returns the switching device to the special mode. The embedded device is either restarted or suppressed.

[0072] A corresponding user message is displayed on the screen, prompting the operator, for example, to relocate the switching device.

[0073] If a valid threshold is found, the programming device initially defines the temporary program as a permanent program for the switching device, initially with overdrive pacing. Thereby, the embedded device remains suppressed.

[0074] Subsequently (and only after the switching device has verified the permanent program), the embedded device is permanently stopped by the programming device using a special command.

[0075] In the described system and method, the stimulation configuration of the embedded device can be transmitted to the switching device. An interruption in communication between the programming device and the switching device and / or the embedded device leads to the end of the temporary program in the switching device (return to the special mode), and the embedded device is readjusted or suppressed again at the fundamental frequency.

[0076] Another command sequence from the programming device to the switching device stops the overdrive pacing in the switching device by gradually returning the rate to the basic rate. Subsequently, the switching device stimulates or is suppressed at the base rate.

[0077] All programming provides appropriate iterations to be sufficiently robust against interference.

[0078] According to a further alternative embodiment of the present method, the medical device forms part of a two-implant dual-chamber therapy system, the two-implant system includes a further medical device, the medical device forms a slave device, and the further medical device forms a master device. In particular, each master device passes its respective command signal from the programming device to the slave device.

[0079] In the following embodiments, the features and advantages of the present invention will be described with reference to the drawings.

Brief Description of the Drawings

[0080]

Figure 1

Figure 2

Figure 3

Mode for Carrying Out the Invention

[0081] FIG. 1 shows an embodiment of a programming device 1 according to the present invention for replacing an implanted medical device 10 with an implantable medical exchange device 30. The programming device 1 transmits a command signal S1 to the medical device 10 to be replaced, changes the address of the medical device 10 to a new address different from the address of the exchange device 30, and enables independent communication between both the medical device 10 and the exchange device 30 and the programming device 1.

[0082] As shown in FIG. 1, the present invention can constitute a single implant system and can be used, for example, to replace a leadless pacemaker 10 implanted in the ventricle 2b of a patient's heart 2. Alternatively, as shown in FIGS. 2 and 3, the present invention can also be used, for example, to replace one of two medical devices 10, 20 of a 2-implant system. Here, one of the medical devices 10, 20 can be a leadless pacemaker 10 implanted in the ventricle 2b, and the other medical device 20 can be a leadless pacemaker 20 implanted in the atrium 2a. In particular, the pacemaker 10 implanted in the ventricle 2b constitutes a master device, and the other pacemaker 20 constitutes a slave device.

[0083] In particular, according to one embodiment, the present invention is based on the idea of using a logic-based communication protocol and a command processor that includes a configurable receiver address. In particular, a command signal is only responded to if the command signal explicitly targets that device 10, 20, 30. Preferably, all implants 10, 20, 30 for a particular heart chamber 2a, 2b are shipped with a factory default address and are automatically used until changed. (For example, when the battery 12, 22 of the device 10 or 20 in question is depleted) A command signal S1 is supported that changes the address of the device 10 or 20 to be replaced to an alternative address shown as the new address. When an exchange device 30 is implanted, the addresses of the depleted devices 10, 20 are first changed to the new address. The programming device 1 can then communicate independently with both the depleted device 10 or 20 and the exchange device 30. This enables a command signal to be directed to each of the devices 10 or 20, 30 to support the role of that device in operation. The communication protocol includes one or more predefined broadcast addresses independent of their assigned addresses to which all devices 10, 20, 30 will respond. Such broadcast commands can be used to trigger simultaneous actions in a portion of multiple devices.

[0084] According to one embodiment, the programming device 1 reversely transmits a command signal S1 to the switching device 30 to change the address of the switching device to something different from that related to the medical devices 10, 20, and the additional broadcast command or a series of broadcasts and device-specific commands (not explicitly shown in any of the figures, S0) proceeds with relaying S1 to obtain addressing information from all medical devices (switched or otherwise) accessible (directly or indirectly) by the programming device 1.

[0085] Fresh devices at factory shipment are preferably always shipped in the stop mode. As shown in FIG. 1, the switching device 30 is first activated by a command signal S2 from the programming device 1 in an idle state where the treatment is interrupted but the detection is active. Additional command signals can be used to confirm that the detection is functioning properly. Next, a command signal S4 is issued to the device 10 in which it is embedded to configure it in an out-of-the-way state that delivers treatment at a low basic rate and is suppressed by the detected activity from the heart or the switching device. Next, a command signal S3 is issued to the switching device to start pacing for a predetermined number of cardiac cycles (capture threshold test mode) or to switch to an on-state pacing output that remains active according to either active communication conditions and / or related timeouts. If capture is detected when the switching device 30 is pacing, the clinician uses the programming device to configure an appropriate permanent pacing therapy for the switching device and subsequently issues a command signal S6 instructing the switching device 30 to pace with the new settings. The clinician is then given the opportunity to permanently deactivate the implant that was originally targeted for replacement, and for this purpose, command S5 is used.

[0086] As described above in connection with FIG. 1, the present invention can be used to replace a single medical device 10 of a single implant system (which is shown in the ventricle of FIG. 1 but may be present in the atrium in other possible embodiments). Alternatively, the replacement of a master device 10 (shown in the ventricle in FIGS. 2 and 3 but may be present in the atrium or other locations in other possible embodiments) or a companion slave device 20 (arranged in the atrium in FIGS. 2 and 3 but may be present in the ventricle or other locations in other possible embodiments) can be achieved with a 2-implant system using the present invention described below with reference to FIGS. 2 and 3.

[0087] In particular, the single implant system shown in FIG. 1 has a leadless implant 10, e.g., a VDD implant that enters the ventricle 2b, in a single heart chamber 2b (note that this is a dual chamber treatment implemented using a single implant system). This is programmed by an external programming device 1. Typical two-implant systems such as those shown in FIGS. 2 and 3 may have a leadless pacemaker 20 in the right atrium 2a and a leadless pacemaker (10) in the right ventricle 2b. Together, these can constitute a DDI or DDD pacemaker system. If there are two or more implants 10, 20 in system 2, the programming device 1 preferably communicates directly only with one of them, the master device 10. The master 10 communicates with the other implants 20, i.e., the slave devices 20, to configure it. In a preferred embodiment, the programming device 1 communicates with the master 10 using, for example, inductive communication, and the master and slave devices 10, 20 communicate with each other using an independent communication system such as an impedance-based or ultrasonic-based physical network layer. For this purpose, both devices 10, 20 may include corresponding communication units 11, 21. This means that the telemetry head (wand) of the programming device 1 only needs to be placed in an optimal position to communicate with the master 10 and is not placed in a compromised position necessary to bring both implants 10, 20 within range simultaneously.

[0088] In the case of a single implant system as shown in FIG. 1, the programming device 1 communicates with a single medical device 10 using, for example, an inductive coupling telemetry path. The logic within the medical device 10 detects when a message (e.g., a command signal) is directed to a destination by comparing the destination address in the message with the address stored therein. A command signal S1 is transmitted, which is interpreted by the hardware command processor of the implant 10 and changes its address to a new address. As shown by the arrow in FIG. 1, the switching device 30 is located within the heart 2. The programming device 1 communicates with both devices 10, 30 using the destination address to distinguish which one is being addressed. The switching device 30 has an address at factory shipment.

[0089] Regarding the replacement of the master device 10 in a two-implant system as shown in FIG. 2, the same procedure as described above for the single implant system can be followed. The master and slave states in a particular device for the purpose of passing communication from the programming device 1 can be pre-configured at the factory or can be configurable as part of the setup of the device 10. The master 10 can simply represent the ability to pass commands to another device 20 that will be made the device containing most of the replacement algorithm, or the master 10 can have the details of the replacement algorithm incorporated into commands whose command processor knows the processing method. The slave device 20 is not affected by the processing since it does not use an inductive telemetry system.

[0090] In the case of replacing the slave device 20 as shown in FIG. 3, the programming device 1 starts the replacement by transmitting commands (e.g., S1 to S6) to the master device 10 using an inductive telemetry system. The master 10 functions as a relay device between the programming device 1 and the slave device 20 by responding to the inductive commands that cause the intracardiac commands to be transmitted to the slave 20 (e.g., using the impedance, ultrasonic, or other non-inductive physical layer telemetry systems 11, 21). The master 10 transmits a command S1 to the slave device 20 instructing it to change to a new address. The new slave (replacement device 30) is implanted in the atrium 2a (see arrow) and is activated in an idle state by the command signal S2 of the programming device 1. This has the default address at factory shipment. Impedance, ultrasonic, or other non-inductive physical layer messages are received by both slave devices 20, 30, but each only responds to commands that match its address. The old slave 20 is set to a temporary "out of the way" state that only provides corrective backpacing using the transmission of S4 from the program device 1 to the master 10, and relays the messaging to the slave 20. The new replacement slave 30 is tested by transmitting a command signal S3 to the new slave 20 (again passing through the master 10) to pace it while the old slave 30 has its pacing suppressed by the presence of a higher rate output from 30. If the new slave 30 shows an executable tissue engagement and pacing capture state, the new slave is configured to a new permanent program state that delivers therapy from 30 using S6 (again passed from the program device via the master 10). Finally, in conjunction with appropriate clinical warnings, the old slave 20 is permanently stopped (by receiving a command signal S5 from the programming device via the master 10). Ideally, the management of the new permanent program within 30 and the permanent stop of 20 are performed as a smooth and coordinated process.

[0091] In particular, the present invention provides a programming system that combines information from multiple implanted devices into a single GUI, such that a user can adjust and consider parameters across replacement devices and devices to be replaced. Such support can take the form of presenting side-by-side the program parameter settings associated with the two devices to easily highlight differences, facilitate transfer, and enable user adjustment, a very preferred approach for embodiments that force a clinician to sequentially communicate myopically between each device to remember or document (outside the GUI) settings between each device to ensure the appropriate state of the other. (Note: Such user control configurations do not mean that the programming device is forced to send messages to two implants simultaneously. The same mechanism can be applied to other systems having multiple interacting implantable medical devices (IMDs).

[0092] Accordingly, the present invention enables a safe replacement procedure involving testing before starting a new device and stopping an old device. In particular, by using a master device to program a slave device via intracardiac communication, the programming device wand can be placed in the best location to communicate only with the master 10.

[0093] With simultaneous connection and addressable commands, the programming device 1 can adjust the configuration and operation of multiple devices 10, 20, 30 without the need to prevent communication from being received and actuated by unintended devices within the system.

Claims

1. An implanted medical device (10; 20), an implantable medical exchange device (30), and a programming device (1) for exchanging the implanted medical device (10; 20) with the implantable medical exchange device (30) using the programming device (1), the system comprising: the programming device (1) is configured to transmit a first command signal (S1) to the implanted medical device (10; 20) to enable independent communication of the programming device (1) with both the implanted medical device (10; 20) and the implantable medical exchange device (30), and to change the address of the implanted medical device (10; 20) to a new address different from the address of the implantable medical exchange device (30).

2. The system according to claim 1, wherein the programming device (1) controls a communication protocol, and the communication protocol includes a predefined broadcast address independent of their assigned addresses to which at least the implanted medical device (10; 20) and the implantable medical exchange device (30) will respond.

3. The system according to claim 1, wherein the programming device (1) transmits the first command signal (S1) to the implantable medical exchange device (30) to change the address of the implantable medical exchange device (30) to an address different from the address of the implanted medical device (10, 20).

4. The system according to claim 1, 2 or 3, wherein the implanted medical device (10; 20) is a first implantable leadless cardiac pacemaker that can be implanted in a patient's heart (2), the implantable medical exchange device (30) is a second implantable leadless cardiac pacemaker, and the implantable medical exchange device (30) is configured to operate in an idle state where the implantable medical exchange device (30) is configured to detect cardiac events but is prevented from applying pacing pulses to the heart (2).

5. The system according to claim 4, wherein the programming device (1) is configured to transmit a second command signal (S2) to the implantable medical exchange device (30) to configure the implantable medical exchange device (30) to an idle state.

6. The system according to claim 5, wherein the programming device is configured to transmit a third command signal (S3) to the implantable medical exchange device (30), and the third command signal (S3) is configured to apply pacing pulses to the heart (2) of the patient by the implantable medical exchange device (30) for a predetermined number of cardiac cycles.

7. The system according to claim 5 or 6, wherein the programming device (1) is configured to transmit a fourth command signal (S4) to the new address of the implanted medical device (10; 20) after transmitting the second command signal (S2).

8. The system according to claim 7, wherein the programming device (1) is configured to transmit a sixth command signal (S6) to the implantable medical exchange device (30) to activate the implantable medical exchange device (30).

9. The system according to any one of claims 1 to 8, wherein the programming device (1) is configured to transmit a permanent stop command signal (S5) to the new address of the implanted medical device (10, 20) when capture of the patient's heart (2) is approved or confirmed by the implantable medical exchange device (30).

10. The system according to any one of claims 1 to 9, wherein the implanted medical device (10; 20) forms part of a single implant system, wherein the implanted medical device (10; 20) is the only implanted medical device (10; 20) of the system (2).

11. The implanted medical device (10) forms part of a two-implant system, the two-implant system includes a further implanted medical device (20), the implanted medical device (10) forms a master device, the further implanted medical device (20) forms a slave device, and the programming device (1) is configured to transmit any one of the first command signal (S1), the fourth command signal (S4), and the permanent stop command signal (S5) to the slave device (20) via the master device (10). The system according to claim 9, which cites claim 7.

12. A method of operating a programming device (1) for replacing an implanted medical device (10; 20) with an implantable medical exchange device (30), the method comprising: The programming device (1) transmits a first command signal (S1) to the implanted medical device (10; 20) to change the address of the implanted medical device (10; 20) to a new address different from the address of the implantable medical exchange device (30) to enable independent communication of the programming device (1) with both the implanted medical device (10; 20) and the implantable medical exchange device (30); The programming device (1) transmits an activation command signal (S2) to the implantable medical exchange device (30) to activate the implantable medical exchange device (30) so that the implantable medical exchange device (30) is configured to detect cardiac events of the patient's heart (2), but is in a passive state where applying a pacing pulse to the heart (2) is prevented; After activating the implantable medical exchange device (30) to be in the passive state, the programming device (1) transmits a third command signal (S3) to the implantable medical exchange device (30) to cause the implantable medical exchange device (30) to apply a pacing pulse to the heart (2) for a predetermined number of cardiac cycles. During a predetermined number of cardiac cycles, the programming device (1) transmits an interruption command signal (S4) to the new address of the implanted medical device (10; 20) so as to interrupt the application of the pacing pulses of the implanted medical device (10; 20) to the heart (2). When capture of the heart (2) is detected by the implantable medical exchange device (30) with respect to the pacing pulses applied by the implantable medical exchange device (30), the programming device (1) transmits a stop command signal (S5) to the new address of the implanted medical device (10; 20) so that the implanted medical device (10; 20) is stopped. A method comprising the step of the programming device (1) transmitting a start command signal (S6) to the implanted exchange device (30) to start the implantable medical exchange device (30) and apply pacing pulses to the heart (2).

13. The method according to claim 12, wherein the programming device (1) transmits the first command signal (S1) to the implantable medical exchange device (30) to change the address of the implantable medical exchange device (30) to an address different from the address of the implanted medical device (10, 20).

Images