WO2013080038A2

WO2013080038A2 - Implantable medical device communications

Info

Publication number: WO2013080038A2
Application number: PCT/IB2012/002771
Authority: WO
Inventors: Dan Gelvan; Arieh Meitav
Original assignee: Sirius Implantable Systems Ltd.
Priority date: 2011-11-28
Filing date: 2012-11-28
Publication date: 2013-06-06
Also published as: WO2013080038A3

Abstract

In one aspect, the invention relates to the combination of a plug-in communication adaptor and a leadless implanted device and how they communicate wirelessly with each other within the body of a patient and how the adaptor plugs into a conventional master device (such as an implanted pacemaker or any type of implanted electrical stimulator). In another aspect, the invention relates to wireless communication between an implanted device and an external device via a coupling device that can be implanted into the patient's body or located external on or near a surface of the patient's body.

Description

IMPLANTABLE MEDICAL DEVICE COMMUNICATIONS

Cross-Reference

This application claims priority to and the benefit of Provisional U.S. Patent Application Serial No. 61/563,930, filed on November 28, 2011, the entire contents of which are

incorporated herein by reference.

Technical Field

The invention generally relates to communications with and between implantable medical devices.

Background Information

A wide variety of implantable medical systems are known and available for monitoring physiological conditions and/or delivering therapies. Such systems may include sensors for monitoring physiological signals for diagnostic purposes, monitoring disease progression, or controlling and optimizing therapy delivery. Examples of implantable monitoring systems include hemodynamic monitors, ECG monitors, and glucose monitors. Examples of therapy delivery systems include devices enabled to deliver electrical stimulation pulses such as cardiac pacemakers, implantable cardioverter-defibrillators (ICDs), neurostimulators, neuromuscular stimulators, brain stimulators, gastrointestinal system stimulators, diaphragm stimulators, and lung stimulators. Implantable therapy delivery devices also include drug delivery devices such as insulin pumps and morphine pumps. Implantable therapy delivery systems also are referred to as active implantable medical systems. Electrical devices, characterized by the need for a power source, are typically implanted under the skin and have one or more leads (electrically conducting wires) that connect the device with the site of stimulation and/or the site where the information is collected. Thus, for example, deep brain stimulators are implanted subcutaneously in the upper pectoral region and have leads that connect them to the region of the brain where stimulation is performed. Similarly, gastric stimulators are implanted subcutaneously in the abdominal region and have leads connecting them to the stomach.

In recent years, new leadless devices have been developed to serve a variety of needs. These include among others miniature hemodynamic monitors and leadless electrodes. Leadless devices, often implanted deep inside the body, have their own power sources, whether a primary battery or a means to utilize and/or store energy obtained from outside the device (energy harvesting or energy transfer). Such devices are typically designed to be extremely energy efficient. Consequently, conventional radio wave (RF) communication with other implanted devices or with external (outside the body) devices, such as programmers, cell phones or web links, is often replaced by more energy-efficient communication modes, such as acoustic waves, that propagate well within the largely aqueous environment inside the body. In contrast to the RF norm, communication between an external device and an implanted leadless device that communicates by acoustic waves requires that the external device is in direct contact with the patient's skin.

A cardiac stimulation device (such as a cardiac pacemaker, an ICD, and a CRT device, where CRT stands for cardiac resynchronization therapy) is one kind of active implantable medical system. Any cardiac stimulation device can be referred to as a pacing device or a pulse generator (PG). When leads and electrodes are included with a pacing device, the combination generally is referred to as a pacing system. The leads of a pacing system are used to span the distance between the implant site and the site of action. For example, if a cardiac pacemaker is implanted subcutaneously in the pectoral region of a human patient, electricity-transmitting leads connected to the pacemaker are typically run through the patient's veins to the target site in the patient's heart to provide electrical stimulation pulses from the pacemaker to the target site. Each of the leads will have at least one electrode, typically mounted at or near the distal end of the lead, and it is the electrode that is placed at the target site in the heart that provides the electrical stimulation pulses to the target site in the heart. The electrode also can be used to pick up the heart's electrical signals from the target site, and those received heart signals are transmitted back to the pacemaker via the lead. A lead generally speaking is an electrical conductor covered by an insulator, such as a copper or silver or metal alloy wire with a silicone or polyurethane coating or jacket on it. A lead sometimes is referred to as a pacing lead.

A pacing lead typically is connected to a pacemaker by a standard physical connection such as what is known as an IS- 1 connection. IS- 1 refers to a current standard for a particular type, size, and shape of a female receiving port on a pacemaker and a matching male connector on one end of the lead (which is the proximal end of the lead). Prior to the IS- 1 standard connection coming into widespread use, other connections were used to couple a lead to a pacemaker such as the 3.2 millimeter low-profile connection.

Wireless pacing systems have been developed to address perceived shortcomings of conventional pacing systems that use leads. Leads can physically fail by, for example, breaking of the conductive wire, insulation break or erosion, or dislodgement. And transvenous leads can be difficult to place into certain locations such as the left ventricle of the heart of a human patient.

One kind of wireless pacing system uses one or more so-called leadless electrodes and also a controlling pulse generator device. A leadless electrode is a small wireless device designed to be attached directly to the heart (such as the left ventricle), and it delivers pacing pulses to the heart under the wireless control of a cardiac pacemaker, ICD, CRT device, or other pulse generator that is located elsewhere in the body. The pulse generator of this leadless pacing system sends signals wirelessly to the leadless electrode that is attached to the heart.

Leadless pacing also can be achieved with a leadless pacemaker which is a very small autonomous pacing device that is attached directly to the heart and that both generates and delivers pacing pulses to the heart. A leadless pacemaker essentially is a miniature pacemaker without any leads. The leadless pacemaker is mounted directly in or on the heart. Whereas a system with leadless electrodes has a parent device to which the leadless electrodes are subordinate, a leadless pacemaker is designed to be an independent device with independent logical and technical capacity like that of a conventional pacemaker. Medtronic, Inc. introduced a leadless pacemaker at the annual meeting of the Heart Rhythm Society (HRS) in 2010. Without a wired connection to a parent device, a leadless electrode and a leadless pacemaker (which can be referred to generally and collectively as leadless pacing devices) must get power in some manner other than through one or more wires or other lines connected to the leadless pacing device. The power for a leadless pacing device can come from an implanted parent device that wirelessly transfers energy to the leadless electrode. Such systems for energy transmission by ultrasound or by magnetic induction are described in K.L. Lee's "In the wireless era: leadless pacing" that was published in Expert Rev. Cardiovasc. Ther. 8(2), 171-174 (2010) and also in H. Wieneke's "Leadless Pacing of the Heart Using Induction Technology: A

Feasibility Study" that was published in PACE 32: 177-183 (2009). Or a leadless pacing device may contain an on-board energy source such as a battery or a generator that harvests energy within the body.

Pacing systems are typically monitored by an external (that is, outside of the body of the patient) monitoring and/or programming device or station which is used in conjunction with an implanted pacing device to receive signals and information from the implanted pacing device and/or to set and send down to the implanted pacing device operational parameters and instructions. The sent parameters/instructions could determine the type of pacing done to the patient's heart by the implanted pacing device or set functional parameters such as, for example, output parameters, pacing mode, coordination times between distinct heart chambers, etc. The received signals may provide real time EGM and upload information on device status, system- organ interface and pathological events as well as other relevant data.

Summary of the Invention

It has been discovered that a wired implantable medical system can be made to operate wirelessly, regardless of its type (monitoring or therapy delivery), its particular manufacturer (Medtronic, Inc. or Boston Scientific Corporation to name just two possibilities), and the proprietary nature of the communication protocol it uses. A specific example within the broader class of electrical stimulation and monitoring systems involves a cardiac pacemaker. One of the leads of a two-lead cardiac pacemaker can be removed and in the port from which the lead was removed a small communication adaptor can be inserted. The adaptor is designed to work and communicate wirelessly with a separate leadless electrode, and together the wireless adaptor and the leadless electrode take the place of the hard- wired lead that was removed from one of the two ports of the pacemaker. The invention relates to the combination of the adaptor and leadless electrode and to how they communicate with each other and with the pacemaker without requiring any modifications to the pacemaker and without any knowledge of the proprietary communication protocol used by the pacemaker. As far as the pacemaker is concerned, the described mode of communication is indistinguishable from communication with a hard- wired lead in both of its ports. That is, the pacemaker does not need to be altered in any way, physically or operationally, and it is the communication adaptor that has in it all of the necessary electronics and capabilities to be able to relay signals and information wirelessly between the pacemaker and the implanted leadless electrode. The wireless communication adaptor is a self- powered unit, and it preferably derives its power from the pacing pulses emitted by the pacemaker. The leadless electrode also is independently powered, and it contains electronics and capabilities needed to deliver stimulation to the heart tissue to which it is attached and to communicate wirelessly with the communication adaptor.

Thus, in one aspect, the invention relates to replacing one or more leads of a conventional electrical stimulation system with wireless components. An apparatus for replacing a lead of the stimulation system can include an implantable leadless component and a communication adaptor. The leadless component is configured to be attached to an area or location within the body of a patient (such as the left ventricle of the patient's heart) and to deliver one or more electrical pulses to that area or location within the patient' s body under the control of a conventional master or parent device (such as a conventional pacing device like a pacemaker) that is disposed elsewhere within the patient' s body. The communication adaptor is configured to be inserted into a standard port of the master device and for allowing the master device to wirelessly control and communicate with the leadless component. Embodiments according to this aspect of the invention can include various features. For example, the implanted master device can be a cardiac pacing device or any electrical stimulator, and the implanted leadless component can be a leadless electrode. Examples of cardiac pacing devices include a cardiac pacemaker, an implantable cardioverter defibrillator (ICD), and a cardiac resynchronization therapy (CRT) device. Examples of electrical stimulators include a deep brain stimulator (which gets implanted subcutaneously in the upper pectoral region of a patient and which has leads that connect the implanted stimulator to the region of the brain where stimulation is desired) and a gastric stimulator (which gets implanted subcutaneously in the abdominal region of a patient and which has leads connecting it to the stomach where stimulation is desired). The leadless electrode can be configured to be attached to or within the left ventricle of the heart or some other area of the heart, for example. The communication adaptor can include an energy source to power the communication adaptor, and the energy source can be rechargeable. The communication adaptor also can include a micro-electronic circuit for controlling at least some of the functionality of the communication adaptor, and it also can include wireless transmission/reception capabilities for communicating with the leadless electrode. The adaptor can communicate wirelessly with the leadless electrode using acoustic signals. The leadless electrode can include its own wireless transmission/reception capabilities for wirelessly communicating with the communication adaptor, and those communications with the adaptor can use acoustic signals. Various other embodiments according to this aspect of the invention are possible.

It also has been discovered that any active implantable medical system or device can be made to communicate wirelessly with an external monitoring and/or programming device or station, where external means outside of the body of a human or other mammal, via an innovative communication coupling device that transforms inside-the-body signals (such as acoustic) into electromagnetic signals (such as radio-frequency, RF) that can be picked up by the external device/station or by an external wireless link. The communication coupling device also transforms the electromagnetic signals from the external device/station or link into inside-the- body signals. For example, an implanted leadless pacing device can communicate wirelessly with an external device via a communication coupling device that converts acoustic signals (such as ultrasound) coming from an implanted leadless pacing device into RF signals that are sent to the external device and that also converts RF signals coming from the external device into acoustic signals that are transmitted to the implanted leadless pacing device. The communication coupling device thus effectively serves as a relay device between the implanted leadless pacing device and the external device. The communication coupling device can be made to be attachable to the exterior skin surface of the patient, and could be in the form of a patch to allow such attachment. Or the communication coupling device can be configured to be implanted subcutaneously, and could be in the form of a pod to allow such subcutaneous implantation. The implantable leadless pacing device could be a leadless pacemaker or a leadless electrode, for example.

Thus, in another aspect, the invention relates to a communication coupling device that is used in a medical system, and the communication coupling device can be configured for implantation below the skin of a patient or else configured to be disposed external to the patient such as on or near the exterior skin surface of the patient. The communication coupling device comprises first and second receivers and also first and second transmitters. The first receiver wirelessly receives signals of a first type (such as acoustic) from a first device implanted within the body of a patient, and the second receiver wirelessly receives signals of a second type (such as radio frequency, RF) from a second device located external to the body of the patient. The first transmitter wirelessly transmits first- type signals to the first device, where at least some of the transmitted first-type signals are based on at least some of the second-type received signals. The second transmitter wirelessly transmits second- type signals to the second device, where at least some of the transmitted second-type signals are based on at least some of the first-type received signals. Embodiments according to this aspect of the invention can include various features such as the following. The second receiver and the second transmitter together can constitute an RF transceiver of the coupling device. The implanted first device can be a leadless electrode attached to an area of the patient's heart such as the left ventricle, or the implanted first device can be a communication adaptor that is inserted into a standard port of a pacemaker that is implanted within the body of the patient. The implanted first device can be a leadless pacemaker attached to an area of the patient's heart such as the left ventricle. The second device can be an external programmer. Various other embodiments according to this aspect of the invention are possible.

These and other aspects, features, advantages, and objects of the invention(s) will become clearer with reference to the drawings and the description that follows.

Brief Description of the Drawings Fig. 1A is a block diagram showing the components of a communication adaptor according to the invention.

Fig. IB is a sketch of a possible physical embodiment of the communication adaptor of Fig. 1A.

Fig. 1C is a block diagram showing the components of a self -powered leadless electrode according to the invention.

Fig. ID is a sketch of a possible physical embodiment of the self-powered leadless electrode of Fig. 1C.

Fig. 2A shows one possible configuration of a pacing system, where the pacing system includes a single-chamber pulse generator (PG) and one leadless electrode (LE).

Fig. 2B shows another possible configuration of a pacing system, where the pacing system includes a dual-chamber PG, one LE, and one hard- wired lead/electrode.

Fig. 2C shows yet another possible configuration of a pacing system, where the pacing system includes a dual-chamber PG and two LEs.

Fig. 3A shows one possible configuration of a pacing system, where the pacing system includes one leadless electrode (LE), two hard-wired leads/electrodes, and a triple-chamber pulse generator (PG) such as a triple-chamber cardiac resynchronization therapy (CRT) device.

Fig. 3B shows another possible configuration of a pacing system, where the pacing system includes two LEs, one hard-wired lead/electrode, and a triple-chamber PG.

Fig. 3C shows a variation of the configuration of the pacing system of Fig. 3B.

Fig. 3D shows yet another possible configuration of a pacing system, where the pacing system includes three LEs and a triple-chamber PG.

Fig. 4A shows one possible configuration of a pacing system that involves one single- chamber leadless pacemaker.

Fig. 4B shows another possible configuration of a pacing system that involves two leadless pacing devices.

Fig. 4C shows yet another possible configuration of a pacing system that involves three leadless pacing devices.

Fig. 5 is a block diagram showing the components of a leadless pacemaker. Fig. 6 is a schematic of a system that includes a patient, a leadless pacing device implanted with the patient's body, and devices located external to the patient's body.

Fig. 7, similar to Fig. 6, shows a system in which wireless acoustic communication occurs directly between an implanted leadless device (such as a leadless electrode or a leadless pacemaker) within the body of a patient and an external device outside of the patient's body, where the external device is in contact with the patient's body surface.

Fig. 8 A shows an embodiment in which wireless communication between the implanted device and the external device is routed through an intermediate communication coupling device which could be attached to the external skin surface of the patient or which could be implanted just under the patient's skin.

Fig. 8B is a block diagram showing the components of the communication coupling device shown in Fig. 8 A.

Description

As will be understood better with reference to the two sections that follow, embodiments according to the invention that involve leadless subordinate devices (e.g., leadless electrodes) are at least somewhat different than embodiments according to the invention that involve autonomous leadless devices (e.g., leadless pacemakers). Communication between an implanted leadless device and an implanted parent device is described in the first of the two sections that follow. The communications between an implanted leadless device and an implanted parent device happen entirely within the body of a patient (whether a human or other mammal), and thus in a continuous aqueous medium. Communication with an external (that is, outside the patient's body) device is described in the second of the two sections that follow. The communications between an implanted device and an external device involve a change in medium between the implanted device (which is within the patient's body) and the external device (which is outside of the patient's body). (I) Wireless communication between an implanted leadless device and an implanted parent device:

In one aspect, the invention relates to devices and methods for wireless communication between a subordinate device (such as a leadless electrode) and its parent or master device (such as a cardiac pacemaker or other electrical stimulator) regardless of the brand or manufacturer of the parent device, without requiring prior compatibility of the parent device with the leadless subordinate device or vice versa, and regardless of whether the parent device has been equipped with a means of intra-device communication.

The mode of wireless communication between a leadless device and a parent device may be acoustic, radiofrequency (RF), or by any other method or frequency band that is in use today or later developed.

In accordance with this aspect of the invention, a communicator adaptor is provided to facilitate wireless communication between a leadless device and any of a variety of different brands of parent devices. The adaptor will physically connect to the parent device and will facilitate and allow wireless communication between the implanted parent device and the implanted leadless device. The adaptor can be configured as a "plug" type device that fits into the standard connector block of the parent device. For example, the known IS- 1 connection standard can be used for the adaptor to allow the adaptor to fit into a standard port on any of a variety of known electrical stimulators regardless of the manufacturer. Other connector standards are possible and can be used. The parent device can be a stimulator such as a cardiac pacemaker, an ICD, a CRT device, a deep brain stimulator, or a gastric stimulator, as just some examples. The parent device can instead be some type of monitoring device. The

communication adaptor contains the entire mechanism(s) required to facilitate wireless communications between the parent pacing device and the leadless device. And the leadless device contains the entire mechanism(s) required to communicate wirelessly with the

communication adaptor.

Various types of data are able to be communicated wirelessly between the parent device and the subordinate leadless device via the communication adaptor, in accordance with the invention. For example, the adaptor can allow wireless communication of the following from the parent device to the subordinate device: timing signals for coordination of a subordinate leadless electrode to the rest of a pacing system; output parameters including but not limited to output voltage and pulse duration; stimulation intervals; and instructions such as the performance of a threshold test, sensing test, and other automatic or on-demand functions. And the adaptor can allow wireless communication of various types of data from the subordinate device to the parent device including, for example, endocardiac or epicardiac electrogram (EGM), stimulation threshold, sensing voltage, and other types of data. Other types of data also can be wirelessly communicated between the parent device and the subordinate leadless device via the

communication adapter including, for example, pacing statistics and information about the functioning of the parent device and/or the subordinate device.

Certain functions can be handled solely by the subordinate device alone or solely by the parent device. Other functions can be handled by the two devices collaborating. For example, the leadless device can contain sufficient electronics and/or other components to solely perform inhibition of pacing based on intrinsic electrical activity in the heart that is detected by the leadless device. As another example, it is noted that the parent device can solely determine atrioventricular (AV) delay intervals. And complex functions such as threshold tests, output adjustment and classification of arrhythmia from EGM may be performed by the subordinate device alone, by the parent device alone, or jointly by both devices. The decision about whether the subordinate device, the parent device, or both will perform specific computations may be preprogrammed or may be included as a programmable parameter and will depend on the ability of the parent device to accept and process certain types of data.

The invention can be employed and operated in a variety of scenarios. Some of the pacing system configurations served by the invention are shown in Figs. 2A, 2B, 2C, 3A, 3B, 3C, and 3D.

A pacing system may have a single-chamber pacing device and a single leadless electrode (LE), as shown in Fig. 2A. The pacing device is identified as a pulse generator (PG). A dual-chamber PG may have one LE and one conventional lead which is hard- wired to the PG, as shown in Fig. 2B. The dual-chamber PG may have two LEs, as shown in Fig. 2C. In each of the different configurations shown in Figs. 2A, 2B, and 2C, the PG can be an off-the-shelf and unaltered cardiac pacemaker (or other type of cardiac stimulation device) by any manufacturer and that is designed to be used with hard- wire leads/electrodes. A communication adaptor according to the invention is plugged into at least one of the conventional pacemaker' s standard ports (e.g., IS-1) where the hard- wire lead would normally be inserted, and a LE according to the invention is placed into or onto the heart at a particular desired location. The inventive LE could be placed for example in or on the heart's left ventricle (LV), and the conventional hard- wire lead/electrode could be placed for example in or on the heart's right atrium (RA), as shown in Fig. 2B. Still referring to Fig. 2B, it is noted that the dual-port PG has a hard-wire lead inserted into one of its two ports and an inventive communication adaptor (not shown) inserted into the other one of its two ports. It is that inserted communication adaptor that allows the dual-port PG to communicate wirelessly with the inventive LE that is disposed in or on the heart's LV. The dual-port PG simultaneously is communicating with the electrode in the RA via the hard- wire lead that is inserted into one of the PG's two ports.

It is noted at this point that the LE or any leadless device according to the invention can be located in or on a chamber of a patient' s heart or in or on any location within the body of the patient.

A biventricular triple-chamber pacing device that can be referred to as a CRT (cardiac resynchronization therapy) device is described as an example of multiple chamber pacing or ICD devices. As shown in Figs. 3A, 3B, 3C, and 3D, and in accordance with the invention, a CRT device (which is identified as a PG) can have one, two, or three inventive leadless electrodes (LEs), and thus can have respectively two, one, or no conventional leads. In Fig. 3A, the three- chamber PG has a single LE in or on the left ventricle (LV) two conventional hard-wire leads with electrodes in the heart's right atrium (RA) and its right ventricle (RV). The triple-chamber PG may instead have one conventional lead/electrode which is hard- wired to the PG and two LEs, as shown in Fig. 3B. Fig. 3C shows a variation of what is shown in Fig. 3B, in that the hard- wired electrode is in or on the heart's RV in Fig. 3B but in or on the heart's RA in Fig. 3C, and the second LE is in or on the RA in Fig. 3B but in or on the RV in Fig. 3C. The triple- chamber PG may have three LEs, as shown in Fig. 3D. In each of the different configurations shown in Figs. 3A, 3B, 3C, and 3D, the PG is an off-the-shelf and unaltered triple-chamber CRT device (or other type of cardiac stimulation device) by any manufacturer and that is designed to be used with hard- wire leads/electrodes. A communication adaptor according to the invention is plugged into at least one of the conventional CRT device's standard ports (e.g., IS-1) where the hard- wire lead would normally be inserted, and each of the LEs according to the invention is placed into or onto the heart at a particular desired location. Two inventive LEs could be placed for example in the heart' s LV and its RV, and a single conventional hard- wire lead/electrode could be placed for example in the heart's RA, as shown in Fig. 3C. Still referring to Fig. 3C, it is noted that the triple-chamber PG has a hard- wire lead inserted into one of its three ports and an inventive communication adaptor (not shown) inserted into each of its two other ports. It is those two inserted communication adaptors that allow the triple-chamber PG to communicate wirelessly with the two inventive LEs that are disposed in the heart's LV and RV. The triple- chamber PG simultaneously is communicating with the electrode in the RA via the hard- wire lead that is inserted into one of the PG's three ports.

It is noted with references to Figs. 2A, 2B, 2C, 3A, 3B, 3C, and 3D that, when more than one inventive LE is implanted, each of the LEs preferably will use a unique identifier that may be preprogrammed into the LE or may be programmable as required. The identifier will prevent cross talk between each of the multiple LEs and their respective wireless communication channels.

In Figs. 2A, 2B, 2C, 3A, 3B, 3C, and 3D, the heart is shown and LEs and a PG are used, but it should be noted that these are just examples. Another organ, area, or location within the body of the patient could be used instead of the heart. And, the LEs could instead be any type of leadless device, whether active like an LE or passive such as a monitor of some type. The PG could instead be any kind of electrical stimulation parent device or another type of implantable parent device.

Described hereinbelow are some aspects of the wireless communications scheme according to the invention, whereby instructions and functional information are wirelessly communicated from an implanted parent device to one or more implanted subordinate devices via one or more of the communication adaptors that are physically inserted into one or more of the standard ports of the parent device. Wireless communications according to the invention is accomplished by certain algorithms that encode data and instructions to be compatible with the standard input-output functions of a conventional implantable parent device such as an implantable cardiac pacemaker manufactured by Medtronic, Inc. or by any other company. A communication adaptor according to the invention is configured to be plugged into a standard port of a conventional parent device. Once plugged into the parent device, the adaptor will sense and convert a variety of parameters that come from the parent device via that port. The parameters can be, for example, pacing parameters (duration, output, timing, etc.) of the stimulation pulse originating from the parent device. The adaptor converts the sensed/received parameters into operating instructions that can be understood and used by the leadless device once sent wirelessly from the adaptor to the leadless device. The adaptor contains all of the necessary electronics and other components required for it to perform all of its functions including sensing of output parameters (e.g., pulse amplitude and duration and the timing of the pulse) from whatever parent device it is plugged into, converting those sensed/received parameters into digital encoded signals, and wirelessly transmitting those signals to an inventive leadless device.

In order for the battery in the implantable parent device to last as long as possible, the communication adaptor and/or the implantable leadless device may have the ability (whether fixed or programmable) to multiply the output parameters, such that a low output (including but not limited to voltage, current, or pulse duration) at the parent device (e.g., 0.5 Volts) could be programmed to be multiplied (e.g., four times) and result in instructions for a higher output (e.g., 2.0 Volts) being delivered wirelessly from the adaptor to the leadless device, which in turn will deliver the instructed output voltage to the cardiac tissue or other intra-body tissue of the patient where the implanted leadless device is located. Additionally, the communication adaptor may be set to high impedance (for example, up to 3000 Ohms which is the upper limit of the adequate range in most conventional pacemakers) to save current drain. Alternatively, the impedance may be set to match the actual pacing impedance calculated by a leadless electrode, in order to make the impedance reading available to the parent device.

The implanted leadless device (such as a leadless electrode) will send information wirelessly back to the plugged-in communication adaptor, for the adaptor to then convey that information to the implanted parent device into which it is plugged. The primary and most important form of this information is the EGM, when the leadless device is a leadless electrode. The EGM may be transmitted wirelessly from the leadless electrode to the adaptor in its basic unmodified format, or it may be reduced to a compressed format by the leadless electrode (e.g., by reducing repetitive data, transmitting differential patterns, subtracting signals from consecutive cycles, etc.) prior to wireless transmission from the leadless electrode to the adaptor. If compressed, the receiving adaptor could then process the compressed information to decompress it and return it to its full EGM before passing it on to the parent device.

Additional information, including but not limited to the function of the leadless device itself (e.g. charge level, charging efficiency, utilization of energy storage capacity, utilization and status of back-up battery, etc.), which the parent device is not equipped to receive and display, may be imbedded into the EGM or other signal by special algorithms in a format that will be recorded by the parent device, and may be retrieved and decoded by an external programmer or other monitoring device. In one embodiment of such embedding of data into EGM signals, the information will be included as square pulses or other distinct patterns, such as but not limited to repetitive peaks in the signal where the interval and magnitude convey the embedded

information, and superimposed upon the EGM signal in such a way that the parent device will recognize the EGM as abnormal and relegate it to storage for later retrieval during a follow up session or by transmission on a data link. The superimposed pulses will be decodable by an external programmer, a dedicated decoding device, or by a manual scheme for decoding provided to a human operator. In a different embodiment, data will be embedded as digital information within the EGM and include a distinct distortion pattern for the EGM which is recognized as abnormal and stored by the parent device, and may be decoded by transmission or downloading to an external programmer or a decoding device. Given that known external programmers are sealed FDA-approved devices that can only be changed by the manufacturer, the decoding device can be capable of receiving its information from the programmer and then decoding specific messages and codes that are unique to the innovative system described herein and that have been embedded into common signals like EGM.

Household data, including but not limited to pacing impedance, may be transmitted wirelessly from the leadless device to the communication adaptor and used to set or simulate certain parameters, such as the impedance of the communication adaptor as discussed above.

It should be noted that the inventive communication adaptor could be made to

communicate wirelessly with one or more devices or stations that are external to the body of the patient, in addition to being able to communicate wirelessly with an inventive leadless device, when the adaptor is plugged into a parent device. While the wireless communication between the implanted adaptor and the implanted leadless device might be by acoustic signals (such as ultrasonic signals), for example, the wireless communication between the adaptor and an external device could use a different technique or frequency such as, for example, RF.

Having described some of the aspects of the wireless communications scheme according to the invention and some of the basic functionality of the inventive communication adaptor and the inventive leadless device, Figs. 1A, IB, 1C, and ID are now referenced and described. Fig. 1A is a block diagram showing the components of a communication adaptor according to the invention, Fig. IB is a sketch of a possible physical embodiment of the communication adaptor of Fig. 1 A. Fig. 1C is a block diagram showing the components of a self-powered leadless electrode according to the invention, and Fig. ID is a sketch of a possible physical embodiment of the self-powered leadless electrode of Fig. 1C.

Referring to Fig. IB, a communication adaptor 100 according to the invention can be constructed such that it has a proximal portion 102 that is a connector designed to fit into a standard connector block of a conventional pacing device and connect electrically to the electrical terminals. At present, the IS-1 standard is almost universally used for pacing lead connectors, and it is the preferred configuration of the communication adaptor's connector, but the connector type may be changed to conform to another type of connection such as another current connector standard or a future standard adopted in the industry. Other types of parent devices may use different connection standards other than IS-1. For example, an implantable defibrillator may use one or more DF-1 connectors for the high- voltage lead. DF-4 is an emerging standard. Other connector types or standards are possible and can depend on the type of parent device. The adaptor 100 also can have a distal portion 106 that contains its

communications module. All of the rest of the electronics and other components also are contained within the housing configuration of the adaptor 100. The adaptor 100 could be a silicone encased plug, for example. Other types of housing configurations for the adaptor 100 are possible. The distal portion 106 can be bulb-shaped, spherical, shaped as an oblong tube, or shaped in any other way deemed appropriate or desirable to contain the necessary parts and to perform the required functions. When plugged into a port of a parent pacing device, the adaptor 100 could be configured such that the end of its distal portion 106 extends out a few centimeters (such as, for example, 0.5 cm to 5 cm) from the pacing device. In general, the distal portion 106 and the adaptor 100 overall are shaped not to interfere with the normal operation of the parent device and not to interfere with one or more other adaptors 100 and/or one or more leads that are plugged into the parent device.

As seen in Fig 1A, the adaptor 100 contains a number of components including an energy source 110, a micro-electronic circuit 112, a transducer 114, an amplifier 116, and the connector 102.

The energy source 110 can be a rechargeable mechanism such as one or more

rechargeable batteries or else one or more capacitors. These batteries or capacitors can store the energy of the pacing pulses emitted by the parent pacing device into which the adaptor 100 is plugged, and it is noted that each of these pulses typically is in the range of 0.5 Volts to 8 Volts and typically has a duration of 0.05 milliseconds to 1.5 milliseconds. The energy source 110 provides all of the power needed by the adaptor 100 to perform all of its functions and operations. It is possible to use a small conventional primary battery as the power source instead of a rechargeable mechanism for the energy source 110, but such a battery is not preferred.

The micro-electronic circuit 112 can be or can include a microprocessor. The circuit 112 handles all adaptor functions described herein including, but not limited to, the following functions: signal processing (e.g., EGM), detection and reporting of output parameters, adjustment of output impedance, transfer of timing signals and other orders and instructions, decoding, decompressing, repetition or generation or mock signals. The circuit 112 converts the details (for example, timing, output, and duration) of each of the received (from the plugged-into pacing device) pulses into instructions for the leadless electrode. The circuit 112 also adapts wirelessly received input (from the leadless electrode) into a format that is readable by the parent pacing device into which the adaptor 100 is plugged. The circuit 112 also accomplishes on its own or else in conjunction with one or more other components of the adaptor 100 the

functionality of the adaptor 100 described herein. The circuit 112 can be constructed from miniature individual components such as resistors, capacitors, and inductors, but the circuit 112 preferably includes one or more specially designed integrated circuit (IC) chips, programmable gate arrays, microcontrollers, microprocessors, or other type of electronics. The circuit 112 can be a miniature electronic computer system that includes a processing unit, data and/or software storage, and input/output capabilities.

The transducer 114 of the adaptor 100 performs the wireless transmission and wireless reception functions communicated to it by the circuit 112 via the amplifier 116. It can be an acoustic (e.g., ultrasound) transducer, but other types of communication are possible such as radio-frequency (RF). Acoustic communication is preferred for the adaptor 100 because it requires much less power than RF, but the communication adaptor 100 can work with a communication mode other than acoustic. The transducer 114 could allow acoustic wireless communication to/from the implanted leadless device, and it also could allow acoustic or some other mode of communication (such as RF) with one or more devices or stations external to the body of a human (or other mammal) patient into which the adaptor 100 is implanted when in use with an implanted parent device.

The amplifier 116 amplifies the incoming signals to allow them to be handled properly by the circuit 112, and the amplifier 116 amplifies the outgoing signals to a level adequate for transmitting data to the leadless pacing device 200 according to the acoustic path between the adaptor 100 and the device 200.

In its simplest form of operation, the communication adaptor 100 receives a pulse from the pacing device into which the adaptor 100 is plugged and then relays a timing signal wirelessly to the leadless electrode in order to synchronize the pulse delivered to the heart by the leadless electrode with one or more other pulses that are being delivered to one or more other areas of the heart by the pacing device through conventional hard- wire leads.

The wireless communication between the leadless electrode and the communication adaptor is preferably protected and coded to prevent interference from non-specific background noise. If more than one leadless device is being used with a single adaptor, the adaptor 100 must be configured to be able to communicate separately with each of the separate leadless devices. Each of the separate leadless devices could have assigned to it or associated with it, for example, some sort of unique identifier such as a unique ID code, a separate frequency or frequency band, a different way of encoding information, or some other way to keep channels from cross-talking.

If a single adaptor 100 is to be used and is to communicate with more than one leadless device, the adaptor 100 is capable of wirelessly sending specific information to each of the leadless devices or, alternatively, a unified parameter signal to all leadless devices and a specific timing signal to each of the leadless devices. These modes of operation require that the parent device (such as some type of pulse generator including, for example, a cardiac pacemaker, a CRT device, or an ICD) provides specific information to its plugged-in communication adaptor 100, which is subsequently transmitted wirelessly from the adaptor 100 to the different leadless devices as required.

The reverse wireless communication, from leadless devices back to the adaptor 100 and then to the pulse generator or other implanted parent device, will be performed in a similar manner, with the leadless device(s) wirelessly transmitting data such as EGM back to the parent device via the adaptor 100. The communication adaptor 100 relays the transmission data (e.g., EGM) to the parent device by translating the communicated signal back to electrical/electronic data, which will, for all practical purposes be indistinguishable from an EGM signal that the pulse generator would otherwise collect through a plugged-in conventional lead. Amplification of the signal received wirelessly by the communication adaptor 100 may be performed by the amplifier 116 as needed to satisfy the input requirements of the pulse generator or other parent device.

Additional data, including but not limited to statistical data, pacing impedance, energy source status, and pacing capture may be wirelessly transmitted back from the leadless electrode through the communication adaptor 100 to the pulse generator.

The registration and utilization by the pulse generator of such data, which it is not at present equipped to accept, will either require a modification of its data acquisition system, or, alternatively, will be resolved at the level of the leadless electrode or the communication adaptor 100.

The leadless electrode may be equipped to relay all EGM, whether delayed or in real time, which will then be analyzed by the pulse generator as would any native EGM, and used to make performance decisions (e.g., activation of mode switch and other arrhythmia related adaptations) and to create statistical arrhythmia reports. Alternatively, in order to save energy, the leadless electrode may be equipped to perform a diagnostic analysis of the EGM, analogous to the analysis performed by the pulse generator, and relay only unusual or pathological parts of the EGM to the pulse generator, which will generate its own statistical reports. Performance decisions may be made at either site, if the prerequisite information is available. Thus, as a non-limiting example, mode switch activation, which requires an atrial signal, will typically be performed by the pulse generator, whereas certain output decisions, such as changes in voltage or pulse duration, which is based on capture detection, may be made locally at the level of the leadless electrode.

The method whereby only pathological or otherwise remarkable EGM segments are transmitted from the leadless electrode to the pulse generator may require that a mock EGM signal is supplied to satisfy the pulse generator's need for continuous EGM input. The mock signal may be supplied by the communication adaptor 100, either as a synthesized EGM- mimicking signal or by repeating a sequence of one or more beats recorded from the last EGM transmission from the leadless electrode. The mock EGM would be replaced by a new sequence when a new transmission from the leadless electrode is made. A mock EGM may be coordinated to timing signals corresponding to the actual timing of cardiac activity as sensed by the leadless electrode and communicated to the communication adaptor 100 which will use the timing signals to correctly time the intervals between the cycles of mock EGM transmitted to the parent device.

Performance data including, but not limited to, charging status, back-up battery utilization, lead impedance, and/or sensing amplitude may be encoded by the leadless electrode and superimposed on the EGM transmitted to the parent device. In different embodiments, decoding may take place either in the communication adaptor 100, the parent pacing device, an external programmer, or an add-on module to standard programmers specifically equipped to handle the signals originating from the leadless devices or by a combination of any two or more of these processing sites.

Other types of data, such as device performance data, may be transmitted wirelessly by the leadless electrode to the communication adaptor 100, which would convert the data to a format that the pulse generator is equipped to accept. As an example, pacing impedance, which is measured directly by the leadless electrode, may be transmitted wirelessly by the leadless electrode to the communication adaptor 100, which in turn adapts its own impedance (applied to the pulse generator's output pulses) accordingly. The pulse generator will thus "sense" the correct impedance and collect accurate and reliable statistical data and perform all decision and warning functions appropriately. Turning now to Figs. 1C and ID, one possible embodiment of a leadless device according to the invention is a leadless electrode 200. The leadless electrode 200 preferably is self- powered.

Referring to Fig. ID, the leadless electrode 200 can be constructed as a small button-like device with prongs that insert into the myocardium to allow the leadless electrode 200 to stay on the heart as shown. For more about prongs and other attachment configurations for the leadless electrode 200, refer to co-pending and co-owned Provisional U.S. Patent Application Serial No. 61/581,685, filed on December 30, 2011, and also the nonprovisional patent application filed with priority thereto on or before December 30, 2012, the entirety of both of which being incorporated herein by reference. As seen in Fig 1C, the leadless electrode 200 contains a number of components including an energy source 210, a micro-electronic circuit 212, a transducer 214, and one or more electrode 230.

The energy source 210 can be a high efficiency piezoelectric micro -generator and energy storage system as described in US Patent Application Publication No. US 2011/0304240 Al, the entirety of which is incorporated herein by reference.

The electrode(s) 230 provide the electrical pulse(s) to the heart or other location at or on which the leadless electrode 200 is placed. If the leadless electrode 200 was instead a passive device or other type of active device, it would not have the electrode(s) 230.

The transducer 214 performs the wireless transmission and wireless reception functions communicated to it by the circuit 212 via the communication unit 224. It can be an acoustic (e.g., ultrasound) transducer, but other types of communication are possible such as radio- frequency (RF). Acoustic communication is preferred for the leadless device because it requires much less power than RF, but the leadless device can work with a communication mode other than acoustic. The transducer 214 could allow acoustic wireless communication to/from the plugged- in adaptor 100, and it also could allow acoustic or some other mode of communication (such as RF) with one or more devices or stations external to the body of the patient.

The circuit 212 also accomplishes on its own or else in conjunction with one or more other components of the leadless electrode 200 the functionality of the leadless electrode 200 described herein. The circuit 212 can be constructed from miniature individual components such as resistors, capacitors, and inductors, but the circuit 212 preferably includes one or more specially designed integrated circuit (IC) chips, programmable gate arrays, microcontrollers, microprocessors, or other type of electronics. The circuit 212 can be a miniature electronic computer system that includes a processing unit, data and/or software storage, and input/output capabilities. The micro-electronic circuit 212 can include a number of components such as, for example, a communication unit 224, a power control 216, a processor 240, a therapy unit 220, memory 222, and a sensing unit 218. The function and purpose of these components will now be described.

The communication unit 224 will control and direct all communication between the leadless pacing device 200 and one or more other devices such as a communication adaptor 100, a leadless pacemaker 500, another leadless electrode 200, and/or a communication coupling device 800. The communication unit 224 will format the signals received from the processor 240 and superimpose them upon the carrier wave transmitted to the transducer 214. Incoming communication is processed to isolate the superimposed signal from the carrier wave prior to passing the signals on to the processor 240.

The power control 216 controls the flow of power between the generator or other source of energy and the storage means of the power source and between the energy storage means and the electrode(s) 230 according to the output set by the processor 240 as described in detail in U.S. Patent Application Publication No. US 2011/0304240 Al, the entirety of which is incorporated herein by reference.

The processor 240 handles all logical functions using input from any of the subunits and does the computing, calculations, and decisions according to the imbedded algorhithms.

The memory 222 stores data which is acquired by the pacing device 200 and assigned to storage by the processor 240, such as statistical data, specific sequences of EGM, performance data, and more.

The therapy unit 220 includes the timing circuit and logic for delivery of therapy, including special functions such as timing intervals between distinct chambers of the heart, special therapeutic sequences such as pacing overdrive, and other therapeutic decisions in conjunction with the processor 240.

The sensing unit 218 detects spontaneous activity of a chamber of the heart, determining when a real heartbeat has occurred and inhibits the delivery of a pacing pulse. The sensing unit 218 will also initiate complex patterns of refractory periods and other functions upon sensing intrinsic cardiac activity.

(II) Wireless communication between an implanted leadless device and an external programmer:

The communication between an implanted leadless device and an implanted parent device described in the previous section (which is section I) is performed within the body of the patient and between two implanted devices, and thus in a continuous aqueous medium (which is the patient's body). In addition to its wireless communication channel with the implanted parent device via the plugged-in communication adaptor, as described in the previous section, the implanted leadless device and/or the adaptor may have the capacity to communicate

independently and wirelessly with an external programmer as shall be described in this section (which is section II). In addition to the leadless device which is subordinate to a master or parent pacing device, another type of leadless device that is independent of any parent device, such as that indicated in Figs. 4A, 4B, and 4C, can communicate wirelessly with an external

programmer, as shall also be described in this section II. A leadless pacemaker is a type of autonomous leadless device that is independent of a parent device. Medtronic, Inc. announced a leadless pacemaker in 2010 at the annual meeting of the Heart Rhythm Society (HRS).

A single-chamber leadless pacemaker is designated in Fig. 4A as LP, and it is shown in Fig. 4A as located in or on the left ventricle (LV) of the heart of the human (or other mammal) patient. Fig. 4B shows a leadless electrode (LE) used in conjunction with the LP, with the LP located one located in the LV of the heart and the LE located in the heart's right atrium (RA). The LP has the capacity to function independently and make all required therapeutic and diagnostic decisions according to its embedded logic. Additionally, the LP may have control over all functions of the overall pacing system whereas the LE may be subordinate to the LP. The implanted LP is able to communicate with one or more implanted LEs (and/or one or more other implanted LPs) to transfer for example timing signals, instructions, and data between them. Furthermore, the LP has wireless communication capabilities for communicating with an external programming device that is located outside of the patient's body. Fig. 4C shows an LP and two LEs, with the LP again located in or on the LV and the two LEs located in or on the RA and the heart's right ventricle (RV). Figs. 4A, 4B, and 4C show some of the LP-based pacing system configurations in which the invention can be employed and operated.

Fig. 5 is a block diagram showing a leadless pacemaker (LP) 500. The implanted leadless pacemaker 500 can communicate with a programmer that is located external to the patient's body, with an implanted communication coupling device 800 that then communicates with the external programmer or to a web-link that is located external to the patient's body (such as, for example, a cell phone or other type of portable electronic device), and/or with one or more implanted leadless devices (such as one or more LEs). Many of the components of the LP 500 that are shown in Fig. 5 are the same as, and have the same functionality as, the similarly- numbered components of the leadless device 200 of Fig. 1C. One component that the LP 500 has that the leadless device 200 does not have is one or more physiological sensors 524.

Each of the sensors 524 senses a level of physical activity of the patient and provides its input to the microprocessor 240, and the microprocessor 240 uses the sensor 524 output to adjust the leadless pacemaker's pacing rate accordingly. Examples of sensors that can be used are accelerometers and piezoelectric sensors that detect aspects of body motion, and sensors of physiological aspects of exertion such as respiratory activity (typically thoracic impedance).

Referring to Figs. 6 and 7, a leadless device 604 can be implanted within the body of a patient 602, and a programmer 606 can be located external to the patient's body. The leadless device 604 can be a leadless pacing device such as a leadless electrode. The leadless device 604 can wirelessly communicate with a head 610, 710 that is hard-wired to the programmer 606.

The head 710 can be in physical contact with the skin surface of the patient 602, as indicated in Fig. 7, and a bridging medium such as a gel can be used to enhance wireless acoustic communication between the head 710 and the implanted leadless device 604. If the head 610 is not in physical contact with the external skin surface of the patient 602, the implanted leadless device 604 could wirelessly communicate by radio-frequency (RF) with the head 610 of the programmer 606 and/or with one or more other devices that are external to the body of the patient 602 such as a cell phone 608. Any such other external device can, like the cell phone 608, have relay or transmission/reception capability such as a connection to the Internet which is referred to as a web link in Fig. 6, but an external device does not have to have such connectivity.

Unlike the embodiments depicted in Figs. 6 and 7, an aspect of the invention relates to wireless communication between the implanted device and the external device(s) via an intermediate communication coupling device which could be attached to or placed near the external skin surface of the patient or which could be implanted just under the patient's skin. Referring to Fig. 8A, communication between the implanted leadless device 604 and the external device (such as the programmer 606 and/or the cell phone 608) is through a coupling device 800 which may be attached to the skin surface (a "communication patch") or which may alternatively be implanted subcutaneously (a "communication pod"). The coupling device 800 amplifies the signal from the leadless device 604, or the coupling device 800 converts acoustic communication from the leadless device 604 into radio-frequency (RF) communication to the external device and vice versa. This mode of relayed communication that is depicted in Fig. 8 A will not require contact between the programmer head 610, 710 and the external skin surface of the patient 602 and will be compatible with remote monitoring.

The communication coupling device 800 shown in Fig. 8A thus facilitates

communication directly between one or more implanted leadless devices and one or more an external programmers and/or one or more remote links. In one embodiment, the coupling device 800 will be attached to the skin surface. And, in another embodiment, the coupling device 800 will be implanted in the body subcutaneously or at another location inside the body

commensurate with two-way communication with the implanted leadless device(s) on one hand and the external device and/or remote link on the other.

The coupling device 800 will communicate with the leadless device 604 preferably by acoustic communication, but communication modes other than acoustic can be used. The coupling device 800 will communicate with the external device preferably by RF, but communication modes other than RF can be used.

The coupling device 800 will effectively serve as a relay device, allowing the use of low- energy modes of communication (such as acoustic) inside the body in order to keep the energy drain on the implanted leadless device low, and utilizing more powerful RF communication out of the body to provide an efficient link with a programmer or another external device without the need for contact between the external device(s) and the skin.

The user interaction with a system equipped with a coupling device 800 will resemble that of conventional systems, in that interrogation, programming, uploading of diagnostic memories, and all other functions will be relayed through the coupling device 800 and will be unnoticeable to the external user.

The coupling device 800 may be configured to communicate with a specific dedicated programmer and remote monitoring system or, alternatively, the coupling device 800 may be configured to communicate with programmers and remote monitoring systems provided by Medtronic, St. Jude, Boston Scientific, or any other manufacturer. A further embodiment may contain two or more communication protocols to communicate externally with several different systems (e.g., both with a dedicated system and with the systems of distinct manufacturers). The coupling device 800 may be programmed to use the communication protocol of a specific brand of external system or, alternatively, detect the presence of a specific system automatically.

The coupling device 800 may also be applied to other technologies or used to facilitate communication between implanted devices operating with acoustic communication and external programmers, monitors, or links, such as but not limited to hemodynamic monitors or other leadless pacing devices with different communication modes.

The coupling device 800 may take on additional functions in the system. In its simplest form, it will relay information between the implanted leadless device and an external programmer or remote monitoring system when prompted. In addition, it may independently upload data from the implanted leadless device 604 from time to time and store it until required to transmit it to an external device, either by manual interrogation, by prompting from a remote monitoring system, by scheduling, or by its own initiative if it needs to alert about unusual events. The coupling device 800 may further be equipped to perform analysis and other computing functions on the data received from the implanted device 604.

The coupling device 800 may be used as the sole communication relay or may be used in conjunction with a communication adaptor 100 or leadless electrode 200, both of which are described in the previous section, which is section I. Fig. 8B is a block diagram showing the components of the communication coupling device 800 of Fig. 8A. Like the communication adaptor 100 shown in Fig. 1C, the coupling device 800 includes some of the same components such as the energy source 110, the microelectronic circuit 112, the transducer 114, and the amplifier 116. The coupling device 800 does not have a connector 102 as the adaptor 100 does. The coupling device 800 however does have an RF transceiver 808 which the adaptor 100 typically will not have.

The components of the coupling device 800 functionally provide the coupling device 800 with a first receiver for wirelessly receiving signals of a first type from one or more devices implanted within the patient's body patient and a second receiver for wirelessly receiving signals of a second type from one or more devices located external to the patient's body. The components of the coupling device 800 also functionally provide the coupling device 800 with a first transmitter for wirelessly transmitting first-type signals to the implanted device(s) and a second transmitter for wirelessly transmitting second-type signals to the external device(s), where at least some of the transmitted first-type signals are based on at least some of the second- type received signals and at least some of the transmitted second-type signals are based on at least some of the first- type received signals. If the first- type signals are acoustic and the second- type signals are radio-frequency (RF), this means that coupling device's first receiver and transmitter wirelessly receive and transmit acoustic signals from and to the implanted device(s), and that the coupling device's second receiver and transmitter wirelessly receive and transmit RF signals from and to the external device(s), with the transmitted acoustic signals being based on the received RF signals and the transmitted RF signals being based on the received acoustic signals.

All of the components of the communication coupling device 800 can be contained within a housing configured to be implanted below the skin of the patient or configured to be disposed on or near the exterior skin surface of the patient.

With reference to Figs. 8 A and 8B, it is noted that the communication coupling device 800 can take the form of an external communication patch. The patch contains all of the components of the coupling device 800 and also includes some way or mechanism to attach externally at some point on the surface of the patient's body. The attachment can be as a sticker, a band, a strap, or a harness. The components of the patch, including electronics, power source, and means of attachment, may be fully integrated or alternatively designed such that the durable electronic and the power parts may be attached to a disposable means for skin- attachment and then the durable electronic and power parts may be reused by transferring them to a new disposable attachment means when required. This patch configuration for the coupling device 800 can involve the use of a gel for improved contact efficiency to the exterior skin surface of the patient's body. And this patch configuration can be powered by a primary battery, a generator, or by energy transfer, including periodic charging or energy transfer at the time of interrogation. In a preferred embodiment, the patch will be powered by a small primary battery.

With continued reference to Figs. 8A and 8B, it also is noted that the communication coupling device 800 can take the form of an implantable communication pod. Like the patch, the pod facilitates communication between one or more implanted wireless devices (such as a leadless electrode 200 or leadless pacemaker 500) and one or more external devices. The communication pod will be implanted in the body through a small incision and may be located subcutaneously or at another location inside the body commensurate with two-way

communication with both the implanted wireless device and the external device. The

communication pod contains all of the components of the coupling device 800 and also includes some way or mechanism to attach to a subcutaneous or other location within the body of the patient. The attachment can be one or more anchors, one or more suture holes, or one or more struts, and the attachment mechanism allows the pod, once placed within the patient's body, to be secured within the patient's body to prevent migration of the implanted pod. The

communication pod may be powered by a primary battery, a generator, or by energy transfer, including periodic charging or energy transfer at the time of interrogation.

It is noted that, as another aspect of the invention, a leadless pacing device could be programmable. The leadless pacing device could be programmed before implantation into the body of the patient or while it is implanted within the patient's body, and the leadless pacing device could be programmed to function as either a leadless pacemaker or a leadless electrode. Leadless pacemakers and leadless electrodes are described herein. See, for example, Figs. 1C and 5. The programmable leadless pacing device has all of the capabilities of a leadless pacemaker 500, but by turning certain functions on or off in the embedded software of the device it could be programmed to behave as a leadless electrode 200. The programming can be done on an already- implanted device with the use of a programmer, or the programming can be done as part of the manufacturing of the device and prior to implantation into a patient. An example of a situation where programming an implanted device to change its functionality is when a leadless pacemaker is implanted and thereafter a new functional mode becomes available in new devices that may be valuable for a specific patient. For example, if a conventional pacemaker with new functions is implanted and the already-implanted leadless pacemaker is reprogrammed to become an implanted leadless electrode, the new conventional pacemaker will control the implanted leadless electrode, via a communication adaptor 100 inserted into a port of the new conventional pacemaker, to allow the new functions to be employed within the patient's body. The new functions will direct therapy, and the reprogrammed implanted device becomes a slave that performs basic local functions and carries out the therapeutic design of the new conventional pacemaker. Another situation where a change in function of an already-implanted device may be required is when the patient has a leadless pacemaker in or on an atrium of the heart and a leadless electrode in or on a ventricle of the heart. It normally makes sense to have the leadless pacemaker in the atrium to maintain a healthy sequence of contraction, but, if the patient develops atrial fibrillation, leadership may be lost since the leading implanted device will have a faulty physiological basis for decision making. Reprogramming the ventricular LE to become the LP and the atrial LP to become the LE will restore best therapy and just maintain atrial vigilance. In case the atria revert to sinus or other non-fibrillating rhythm, the ventricular LP will be informed and can incorporate the atrial electrode into the therapy.

If references and citations to other documents (such as patents, patent applications, patent publications, journals, books, papers, and web contents) have been made anywhere herein, all such documents are hereby incorporated herein by reference in their entirety for all purposes.

While the principles of communication, the communication protocols, the

communication adaptor and the coupling devices have been described herein in conjunction with implantable electrical stimulation devices and systems, they may be universally applied to all active or passive implantable devices with communication ability, including but not limited to implantable drug pumps and other drug eluting devices, neuro stimulation devices, brain stimulation devices, devices for stimulation of the gastrointestinal system, the diaphragm, or the lungs, for implantable monitors and for orthopedic devices, both between fully implanted devices and between implanted devices and external programming, monitoring, or other communicating systems.

Various modifications and combinations of what is described herein are considered to be included herein even if not specifically called out. The description is meant to be illustrative and not limiting.

Claims

1. Apparatus for replacing a lead of an electrical stimulation system, comprising:

a leadless device configured for attachment to an area within a body of a patient and for delivering one or more electrical pulses to that area within the patient's body under the control of a parent device disposed elsewhere within the patient's body, the electrical stimulation system including the parent device; and

a communication adaptor configured to be inserted into a standard port of the parent device and for allowing the parent device to wirelessly control and communicate with the leadless device.

2. The system of claim 1 wherein the parent device is a cardiac pacemaker, an implantable cardioverter defibrillator (ICD), a cardiac resynchronization therapy (CRT) device, a deep brain stimulator, a gastric stimulator, or other electrical stimulator.

3. The system of claim 1 wherein the leadless device is a leadless electrode configured to be attached to or within a chamber of the heart.

4. The system of claim 1 wherein the communication adaptor comprises an energy source to power the communication adaptor.

5. The system of claim 4 wherein the energy source is rechargeable.

6. The system of claim 5 wherein the energy source is recharged by pulses emitted by the parent device when the communication adaptor is inserted into the standard port of the parent device.

7. The system of claim 1 wherein the communication adaptor comprises a transducer for wirelessly communicating with the leadless device.

8. The system of claim 7 wherein the transducer wirelessly communicates with the leadless device using acoustic signals.

9. The system of claim 1 wherein the leadless device comprises a transducer for wirelessly communicating with the communication adaptor.

10. A communication coupling device for use in a medical system, the communication coupling device comprising:

a first receiver for wirelessly receiving signals of a first type from a first device implanted within the body of a patient;

a second receiver for wirelessly receiving signals of a second type from a second device located external to the body of the patient;

a first transmitter for wirelessly transmitting first- type signals to the first device, at least some of the transmitted first-type signals being based on at least some of the second-type received signals;

a second transmitter for wirelessly transmitting second- type signals to the second device, at least some of the transmitted second-type signals being based on at least some of the first-type received signals; and

a housing configured to be implanted below the skin of the patient and to contain the first receiver, the second receiver, the first transmitter, and the second transmitter.

11. The communication coupling device of claim 10 wherein the first- type signals are acoustic signals.

12. The communication coupling device of claim 10 wherein the second-type signals are electromagnetic signals.

13. The communication coupling device of claim 12 wherein the electromagnetic signals are radio-frequency (RF) signals.

14. The communication coupling device of claim 10 wherein the second receiver and the second transmitter together comprise a radio-frequency (RF) transceiver.

15. The communication coupling device of claim 10 wherein the first device comprises a leadless pacing device attached to an area of a heart of the patient.

16. The communication coupling device of claim 10 wherein the first device comprises a communication adaptor inserted into a standard port of a pacemaker that is implanted within the body of the patient.

17. The communication coupling device of claim 15 wherein the first device comprises a leadless pacemaker attached to an area of a heart of the patient.

18. The communication coupling device of claim 10 wherein the second device comprises an external programmer or a web link.

19. A communication coupling device for use in a medical system, the communication coupling device comprising:

a second transmitter for wirelessly transmitting second- type signals to the second device, at least some of the transmitted second-type signals being based on at least some of the first-type received signals; and a housing configured to be disposed on the exterior skin surface of the patient and to contain the first receiver, the second receiver, the first transmitter, and the second transmitter.

20. The communication coupling device of claim 19 wherein the first- type signals are acoustic signals, and wherein the second- type signals are radio-frequency (RF) signals.