Request channel wakeup in implantable medical device

Abstract

The present disclosure includes example medical device systems and techniques for communicating between medical devices. An example medical device includes a memory configured to store parameters for therapy delivery of a patient; communication circuitry; an electrical signal generation circuitry; and processing circuitry. The processing circuitry is configured to control the electrical signal generation circuitry to deliver a first electrical signal to an anatomy of the patient. The processing circuitry is configured to control the communication circuitry to communicate with another medical device based on the electrical signal generation circuitry delivering the first electrical signal.

Description

[0001] This application claims the benefit of U.S. Provisional Patent Application Serial No. 63 / 365,307, filed May 25, 2022, the entire contents of which are incorporated herein by reference. Technical Field

[0002] The present disclosure relates to medical devices, and more particularly to medical device systems configured to sense physiological parameters of a patient and / or deliver therapy to the patient. Background Art

[0003] Various medical devices for delivering therapy or monitoring a patient's physiological condition have been used clinically or proposed for clinical use in patients. Examples include implantable medical devices (IMDs) that deliver therapy to the heart, muscles, nerves, brain, stomach, or other tissues and / or monitor conditions associated with the heart, muscles, nerves, brain, stomach, or other tissues. Some therapies include delivering electrical stimulation to such tissues. Some IMDs may use electrodes to deliver therapy electrical signals to these organs or tissues, use electrodes to sense physiological electrical signals inherent in the patient's body (which may be propagated by such organs or tissues), and / or use other sensors to sense the patient's physiological signals. Other medical devices may be attached to the patient or otherwise contact the patient.

[0004] In some cases, a patient may have more than one medical device implanted. For example, when the patient's heart's natural pacemaker and / or conduction system fails to provide synchronized atrial and ventricular contractions at a rate and interval sufficient to maintain the patient's healthy function, an implantable cardioverter-defibrillator (ICD) and an implantable artificial pacemaker may be implanted to provide cardiac pacing therapy to the heart. This anti-bradycardia pacing can provide symptom relief or even life support for the patient. Cardiac pacing can also provide electrical overdrive stimulation (e.g., anti-tachycardia pacing (ATP) therapy) to inhibit or convert rapid arrhythmias, thereby again providing symptom relief and preventing or terminating arrhythmias that may cause sudden cardiac death. Additionally, an ICD may deliver an anti-tachycardia shock in response to detecting a ventricular tachyarrhythmia (e.g., ventricular tachycardia (VT) or ventricular fibrillation (VF)) that is not terminated by ATP (or may not be terminated by ATP).

[0005] Communication between two or more devices associated with a person (e.g., implanted in the person and / or attached to the person or otherwise in contact with the person) may be desirable in many applications, such as for monitoring or managing a patient's health. Communication between these devices can, for example, enable information exchange, coordinated monitoring of health conditions, and / or coordinated therapy to treat health conditions. Summary of the Invention

[0006] Implantable medical devices (IMDs) such as ICDs, cardiac resynchronization therapy (CRT) systems, implantable pulse generators (IPGs), temporary ambulatory pacemakers (TAPs), and external devices such as external computing devices can monitor patient parameters and / or deliver therapies such as ATP therapy or an electric shock to the patient's heart. Such therapies can be delivered to cause the heart to develop a refractory period, thereby terminating a tachyarrhythmia or treating a myocardial infarction.

[0007] Such IMDs may sometimes communicate with each other, for example, to provide information collected by the first IMD to a second IMD or to provide instructions to the second IMD, such as instructions for starting to deliver therapy, instructions for stopping to deliver therapy, and / or instructions for configuring the operation of the second IMD (such as reprogramming the second IMD). In order to communicate with each other, each IMD may typically monitor a communication channel for a communication wake-up signal from another IMD or from an external device. Typically, the amount of data to be transmitted between IMDs is very low, so actually opening the communication channel and transmitting / receiving data does not consume much power. However, monitoring the communication channel for a wake-up signal may be relatively power-consuming because the IMDs may use a relatively large current draw to monitor for the wake-up signal. Because some IMDs typically have a very limited amount of power, it may be desirable to limit, reduce, or completely eliminate monitoring of the communication channel for a communication wake-up signal from at least one of the IMDs. This can reduce the power consumption of the IMDs, thereby extending battery life and / or the time between recharges. When the IMD is implanted in the body, extending battery life can reduce the need for replacement surgery.

[0008] The systems, IMDs, and techniques disclosed herein provide communication between IMDs within a patient without requiring at least one of the IMDs to monitor a communication channel for a communication wake-up signal. For example, a first IMD can deliver a first electrical signal to an anatomical structure (e.g., the heart) of the patient, rather than sending a communication wake-up signal. The anatomical structure may already be monitored by one or more sensors of a second IMD and / or the sensing circuitry of the second IMD, and therefore generally does not increase current consumption. In some examples, the first electrical signal can be configured to generate a physiological response in the anatomical structure, which can be sensed by one or more sensors of the second IMD and / or the sensing circuitry of the second IMD. In other examples, the first electrical signal can be configured to be directly sensed by one or more sensors of the second IMD and / or the sensing circuitry of the second IMD, which can be actively sensed as part of the operation of other IMDs. The first electrical signal can be a signal that would not otherwise be delivered by the first IMD (e.g., the purpose of the first electrical signal is not necessarily to provide therapy or monitor a patient parameter, such as a signal sent to determine the impedance of a target tissue, but rather to cause the second IMD to initiate communication with the first IMD or take some other action). The second IMD can be configured to communicate with the first IMD when the first electrical signal is sensed to be delivered to the anatomical structure. Therefore, the first IMD and the second IMD can use non-channel-based signaling to request communication between them. In this way, the second IMD does not need to use the communication channel to monitor for the communication wake-up signal, thereby saving power. These techniques may be particularly useful in situations where the second IMD is an extremely low-power device. For example, the second IMD can be a lower-power device than the first IMD. While the technology of the present disclosure is generally discussed with respect to two IMDs, any number of two or more IMDs can implement the techniques discussed herein.

[0009] In one example, the present disclosure relates to a medical device comprising: a memory configured to store parameters of a first electrical signal for a patient; a communication circuit system; an electrical signal generating circuit system; and a processing circuit system communicatively coupled to the memory, the communication circuit system, and the electrical signal generating circuit system, the processing circuit system being configured to: control the electrical signal generating circuit system to deliver the first electrical signal to the patient's anatomical structure; and control the communication circuit system to communicate with another medical device based on the electrical signal generating circuit system delivering the first electrical signal.

[0010] In another example, the present disclosure relates to a medical device comprising: a memory configured to store parameters indicating delivery of a first electrical signal to an anatomical structure of a patient; a communication circuit system; at least one of a sensor or a sensing circuit system; and a processing circuit system communicatively coupled to the memory, the communication circuit system, and at least one of the sensor or the sensing circuit system, the processing circuit system being configured to: receive a signal from at least one of the sensor or the sensing circuit system; determine that the signal indicates delivery of the first electrical signal to the anatomical structure of the patient by another medical device; and control the communication circuit system to initiate communication with at least one of the other medical device or a third medical device based on receipt of the signal indicating delivery of the first electrical signal.

[0011] In another example, the present disclosure relates to a method comprising: controlling an electrical signal generating circuit system to deliver a first electrical signal to an anatomical structure of a patient through a processing circuit system; and controlling a communication circuit system to communicate with another medical device through the processing circuit system and based on the electrical signal generating circuit system delivering the first electrical signal.

[0012] In another example, the present disclosure relates to a method comprising: receiving, by a processing circuit system of a medical device, a signal from at least one of a sensor or a sensing circuit system; determining that the signal indicates delivery of a first electrical signal to an anatomical structure of a patient by another medical device; and controlling, by the processing circuit system and based on receiving the signal indicating delivery of the first electrical signal, a communication circuit system to initiate communication with at least one of the other medical device or a third medical device.

[0013] In another example, the present disclosure relates to a method comprising: controlling an electrical signal generating circuit system of a first medical device to deliver a first electrical signal to an anatomical structure of a patient through a first processing circuit system of a first medical device; receiving a signal indicating that the first electrical signal was delivered from the first medical device through a second processing circuit system of a second medical device and from at least one of a sensor or a sensing circuit system; and controlling a second communication circuit system to initiate communication with at least one of the first medical device or a third medical device through the second processing circuit system and based on receiving the signal indicating the delivery of the first electrical signal.

[0014] In another example, the present disclosure relates to a non-transitory computer-readable storage medium having instructions stored thereon that, when executed, cause a processing circuit system to: control an electrical signal generating circuit system to deliver a first electrical signal; and communicate with another medical device via a communication circuit system based on the electrical signal generating circuit system delivering the first electrical signal.

[0015] In another example, the present disclosure relates to a non-transitory computer-readable storage medium having instructions stored thereon that, when executed, cause a processing circuit system to: receive a signal from at least one of a sensor or a sensing circuit system; determine that the signal indicates that a first electrical signal is delivered from another medical device to an anatomical structure of a patient; and based on receiving the signal indicating the delivery of the first electrical signal, control the communication circuit system to initiate communication with at least one of the other medical device or a third medical device.

[0016] This summary is intended to provide an overview of the subject matter described in this disclosure. It is not intended to provide an exclusive or exhaustive explanation of the devices and methods described in detail in the following figures and description. Details of one or more aspects of the present disclosure are set forth in the following figures and description. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1A is a front view of a patient implanted with an example implantable medical device system.

[0018] Figure 1B Is implanted Figure 1A Side view of a patient with an implantable medical device system.

[0019] Figure 1C Is implanted Figure 1A and Figure 1B Lateral view of a patient with an implantable medical device system.

[0020] Figure 2 It shows Figures 1A to 1C Conceptual diagram of an example configuration of an intracardiac pacing device (IPD) of an implantable medical device system.

[0021] Figure 3 It shows Figures 1A to 1C and Figure 2 Functional block diagram of an example configuration of an IPD.

[0022] Figure 4 It shows Figures 1A to 1C A functional block diagram of an example configuration of an implantable medical device system ICD.

[0023] Figure 5 It shows Figures 1A to 1C A functional block diagram of an example configuration of an external device.

[0024] Figure 6 is a flow chart illustrating an example communication technique for a first IMD in accordance with one or more aspects of the present disclosure.

[0025] Figure 7is a flow chart illustrating an example communication technique for a second IMD in accordance with one or more aspects of the present disclosure.

[0026] Figure 8 is a flow chart of an example communication technique for a first IMD and a second IMD according to one or more aspects of the present disclosure. DETAILED DESCRIPTION

[0027] Figures 1A to 1C is a conceptual diagram showing various views of an example implantable medical device system 8. System 8 includes an extracardiovascular ICD system 6 including an ICD 9 connected to medical electrical leads 10 and an IPD 16 configured according to the principles of the present application. Figure 1A is a front view of a patient 14 having a medical device system 8 implanted therein. Figure 1B is a side view of a patient 14 having a medical device system 8 implanted therein. Figure 1C is a lateral view of a patient 14 having the medical device system 8 implanted therein.

[0028] ICD 9 may include a housing that forms an airtight seal that protects the components of ICD 9. The housing of ICD 9 may be formed of a conductive material, such as titanium or a titanium alloy, that may serve as a housing electrode (sometimes referred to as a can electrode). In other examples, ICD 9 may be formed to have or may include one or more electrodes located on an outermost portion of the housing. ICD 9 may also include a connector assembly (also known as a connector block or header) that includes electrical feedthroughs through which electrical connections are made between conductors of leads 10 and electronic components included within the housing of ICD 9. As will be described in further detail herein, the housing may house one or more processors, memory, transmitters, receivers, sensors, sensing circuitry, electrical signal generating circuitry, a power supply, and other appropriate components. The housing is configured to be implanted in a patient, such as patient 14.

[0029] The ICD 9 is implanted outside the left thoracic cavity of the patient 14, for example, subcutaneously and outside the rib cage (subcutaneously or submuscularly). In some cases, the ICD 9 may be implanted between the left posterior axillary line and the left anterior axillary line of the patient 14. However, the ICD 9 may also be implanted in other extrathoracic locations of the patient 14, as described below.

[0030] For example, the lead 10 may include an elongated lead body 12 sized to be implanted in an extracardiac location proximal to the heart, such as within the chest cavity (e.g., Figures 1A to 1C), subcutaneously, or intercostally. In the example shown, the lead body 12 extends upward within the thoracic cavity below the sternum in a direction substantially parallel to the sternum. In one example, the distal portion 24 of the lead 10 can reside in a substernal position such that the distal portion 24 of the lead 10 extends upward substantially within the anterior mediastinum 36 along the posterior side of the sternum. The anterior mediastinum 36 can be considered to be bounded laterally by the pleura 39, posteriorly by the pericardium 38, and anteriorly by the sternum 22. In some cases, the anterior wall of the anterior mediastinum 36 can also be formed by the transverse thoracic muscle and one or more costal cartilages. The anterior mediastinum 36 includes a certain amount of loose connective tissue (such as cellulite), adipose tissue, some lymphatic vessels, lymph glands, substernal muscle tissue (e.g., the transverse thoracic muscle), the thymus gland, branches of the internal thoracic artery, and the internal thoracic vein. The lead 10 can be implanted in other locations, such as above the sternum, offset to the right of the sternum, angled laterally from the proximal or distal end of the sternum, etc. In other examples, the distal portion of lead 10 can reside within a blood vessel in a substernal location, such as, for example, the internal thoracic artery, internal thoracic vein, intercostal vein, superior epigastric vein, or the azygos, hemiazygos, or accessory hemiazygos veins. In this manner, lead 10 remains residing in an extracardiac location outside the heart.

[0031] The lead body 12 can have a generally tubular or cylindrical shape and can define a diameter of approximately 3 French (Fr) to 9 Fr, however, lead bodies less than 3 Fr and greater than 9 Fr can also be utilized. In another configuration, the lead body 12 can have a flat, ribbon-like, or paddle-like shape, wherein at least a portion of the length of the lead body 12 has a solid, woven wire, or metal mesh structure. In such examples, the width across the lead body 12 can be between 1 mm and 3.5 mm. Other lead body designs can be used without departing from the scope of the present application.

[0032] The lead body 12 of lead 10 can be formed by the non-conductive material comprising silicone, polyurethane, fluoropolymer, their mixture and other appropriate materials and be shaped to form one or more lumens (not shown), but these technologies are not limited to this construction. Distal portion 24 can be manufactured to be biased with a desired configuration, or alternatively, can be manipulated into a desired configuration by a user. For example, distal portion 24 can be made of plastic material so that the user can manipulate distal portion 24 into a desired configuration, wherein the distal portion remains unchanged before being manipulated into different configurations. However, distal portion 24 can adopt different configurations, including a straight configuration, a circular configuration or the configuration of any number.

[0033] The lead body 12 may include a proximal end 4 configured to deliver electrical energy to the heart or sense electrical energy of the heart and a distal portion 24. The distal portion 24 can be anchored to a desired location in the patient's body, such as under the sternum or subcutaneously, by, for example, suturing the distal portion 24 to the patient's muscle tissue, tissue, or bone at the xiphoid process entry site. Alternatively, the distal portion 24 can be anchored to the patient or by using a rigid fork, fork, barb, clamp, screw, and / or other protruding element or flange, disc, flexible fork, flap, porous structure such as a mesh element, or a metallic or non-metallic scaffold that promotes tissue growth for bonding, a bioadhesive surface, and / or any other non-piercing element.

[0034] Distal portion 24 includes a defibrillation electrode 28 configured to deliver a cardioversion / defibrillation shock to the patient's heart. Defibrillation electrode 28 may include multiple portions or segments 28a and 28b spaced apart along the length of distal portion 24. Defibrillation electrode segments 28a and 28b may be disposed around or within lead body 12 of distal portion 24, or alternatively, may be embedded within the wall of lead body 12. In one configuration, defibrillation electrode segments 28a and 28b may each be a coil electrode formed from a conductor. The conductor may be formed from one or more conductive polymers, ceramics, metal-polymer composites, semiconductors, metals, or metal alloys, including, but not limited to, one or a combination of the following: platinum, tantalum, titanium, niobium, zirconium, ruthenium, indium, gold, palladium, iron, zinc, silver, nickel, aluminum, molybdenum, stainless steel, MP35N, carbon, copper, polyaniline, polypyrrole, and other polymers. In another configuration, each of the defibrillation electrode segments 28a and 28b may be a flat ribbon electrode, a paddle electrode, a braided or woven electrode, a mesh electrode, a directional electrode, a patch electrode, or another type of electrode configured to deliver a cardioversion / defibrillation shock to the patient's heart.

[0035] In one configuration, the defibrillation electrode segments 28a and 28b are spaced approximately 0.25 cm to 4.5 cm apart from one another, and in some cases, 1 cm to 3 cm apart. In another configuration, the defibrillation electrode segments 28a and 28b are spaced approximately 0.25 cm to 1.5 cm apart from one another. In another configuration, the defibrillation electrode segments 28a and 28b are spaced approximately 1.5 cm to 4.5 cm apart from one another. Figures 1A to 1CIn the illustrated configuration, the defibrillation electrode segments 28a and 28b span a substantial portion of the distal portion 24. Each of the defibrillation electrode segments 28a and 28b can be between approximately 1 cm and 10 cm in length, and more preferably between 2 cm and 6 cm in length, and even more preferably between 3 cm and 5 cm in length. However, lengths greater than 10 cm and less than 1 cm can be utilized without departing from the scope of the present disclosure. The overall length of the defibrillation electrode 28 (e.g., the combined length of the two segments 28a and 28b) can vary according to a number of variables. In one example, the defibrillation electrode 28 can have a total length of between approximately 5-10 cm. However, in other examples, the defibrillation electrode segments 28a and 28b can have a total length of less than 5 cm and greater than 10 cm. In some cases, the defibrillation segments 28a and 28b can be substantially the same length, or alternatively, different lengths.

[0036] The defibrillation electrode segments 28a and 28b can be electrically connected to one or more conductors that can be disposed in the body wall of the lead body 12 and / or can alternatively be disposed in one or more insulating lumens (not shown) defined by the lead body 12. In an example configuration, each of the defibrillation electrode segments 28a and 28b is connected to a common conductor so that voltage can be applied simultaneously to all of the defibrillation electrode segments 28a and 28b to deliver a defibrillation shock to the patient's heart. In other configurations, the defibrillation electrode segments 28a and 28b can be attached to separate conductors so that each defibrillation electrode segment 28a or 28b can have voltage applied to it independently of the other defibrillation electrode segments 28a or 28b. In such cases, the ICD 9 or lead 10 can include one or more switches or other mechanisms to electrically connect the defibrillation electrode segments together to function as a common polarity electrode, so that in addition to being able to apply voltage independently, voltage can also be applied to all of the defibrillation electrode segments 28a and 28b simultaneously.

[0037] In one example, the distance between the nearest defibrillation electrode segments 28a and 28b and the electrodes 32a and 32b is greater than or equal to 2 mm and less than or equal to 1.5 cm. In another example, the electrodes 32a and 32b may be spaced apart from the nearest one of the defibrillation electrode segments 28a and 28b by a distance greater than or equal to 5 mm and less than or equal to 1 cm. In yet another example, the electrodes 32a and 32b may be spaced apart from the nearest one of the defibrillation electrode segments 28a and 28b by a distance greater than or equal to 6 mm and less than or equal to 8 mm.

[0038] Electrodes 32a and 32b can be configured to deliver low-voltage electrical pulses to the heart and / or can sense cardiac electrical activity, such as depolarization and repolarization. Therefore, electrodes 32a and 32b may be referred to herein as pacing / sensing electrodes 32a and 32b. In one configuration, electrodes 32a and 32b are ring electrodes. However, in other configurations, electrodes 32a and 32b can be any of a variety of different electrode types, including ring electrodes, short coil electrodes, paddle electrodes, hemispherical electrodes, directional electrodes, and the like. Electrodes 32a and 32b can be of the same or different types. Electrodes 32a and 32b can be electrically isolated from adjacent defibrillation segments 28a and 28b by including a layer of electrically insulating material between electrodes 32a and 32b and adjacent defibrillation segments 28a and 28b. Each electrode 32a and 32b can have its own separate conductor, allowing voltage to be applied to each electrode independently of the other electrode 32a and 32b located in distal portion 24. In other configurations, each electrode 32a or 32b may be coupled to a common conductor such that a voltage may be applied to each electrode 32a or 32b simultaneously.

[0039] The proximal end 4 of the lead body 12 may include one or more connectors 34 to electrically couple the lead 10 to an ICD 9 implanted subcutaneously within the patient's body (e.g., under the patient's left axilla). The ICD 9 may include a housing that forms an airtight seal protecting the components of the ICD 9. The housing of the ICD 9 may be formed of a conductive material such as titanium or a titanium alloy that may serve as a housing electrode for a particular therapy vector between the housing and the distal portion 24. The ICD 9 may also include a connector assembly that includes electrical feedthroughs through which electrical connections are made between the one or more connectors 34 of the lead 10 and the electronic components included within the housing. The housing of the ICD 9 may house one or more processors, memories, transmitters, receivers, sensors, sensing circuitry, therapy circuitry, power supplies (capacitors and batteries), and / or other appropriate components. The components of the ICD 9 may generate and deliver electrical therapies, such as anti-tachyarrhythmia shocks and ATP or other cardiac pacing.

[0040] The inclusion of electrodes 32a and 32b adjacent to defibrillation electrode segments 28a and 28b provides multiple therapy vectors for delivering electrical stimulation therapy to the heart. Figures 1A to 1CAs shown, at least a portion of the defibrillation electrode 28 and one of the electrodes 32a and 32b can be positioned over the right ventricle, or any other chamber of the heart, to enable delivery of pacing pulses and defibrillation shocks to the heart. The housing of the ICD 9 can be charged with or used as a polarity different from that of one or more of the defibrillation electrode segments 28a and 28b and / or the electrodes 32a and 32b, enabling electrical energy to be provided to the heart between the housing and the defibrillation electrode segments 28a and 28b and / or the electrodes 32a and 32b. When voltage is applied to each defibrillation electrode segment 28a or 28b, each defibrillation electrode segment can have the same polarity as every other defibrillation electrode segment 28a or 28b, enabling delivery of a defibrillation shock from the entirety of the defibrillation electrode 28. In an example where the defibrillation electrode segments 28a and 28b are electrically connected to a common conductor within the lead body 12, this is the only configuration for the defibrillation electrode segments 28a and 28b. However, in other examples, the defibrillation electrode segments 28a and 28b may be coupled to separate conductors located within the lead body 12 and, therefore, may each have a different polarity so that electrical energy can flow between the defibrillation electrode segments 28a and 28b (or between one of the defibrillation electrode segments 28a and 28b and one or more pace / sense electrodes 32a and 32b or a housing electrode) to provide pacing therapy and / or sense cardiac depolarization. In such cases, the defibrillation electrode segments 28a and 28b may still be electrically coupled together (e.g., via one or more switches located within the ICD 9) to have the same polarity, thereby delivering a defibrillation shock from the entirety of the defibrillation electrode 28.

[0041] Additionally, each electrode 32a and 32b can be configured to conduct electrical pulses directly to the heart, or can be configured to sense cardiac depolarizations between adjacent defibrillation electrode segments 28a and 28b (whether disposed on the same defibrillation electrode segment 28a or 28b or on other defibrillation electrode segments 28a or 28b, and / or between proximal electrodes 32a and 32b). Additionally, the electrodes 32a and 32b can conduct electrical pulses between each other (e.g., between one of the electrodes 32a and 32b and the inferior electrode 32a and superior electrode 32b, between one of the electrodes 32a and 32b and the housing electrode, or between multiple electrodes 32a and 32b (of the same polarity) and the housing electrode of opposite polarity). Thus, each electrode 32a or 32b can have the same polarity as each other electrode 32a or 32b, or alternatively, can have a different polarity, so that pacing pulses can be delivered to the heart using different therapy vectors.

[0042] Electrodes 32a and 32b may also be configured to deliver a first electrical signal to the heart of patient 14. The first electrical signal may include one or more pacing pulses and may be a signal used specifically by ICD 9 to notify IPD 16 that IPD 16 should communicate with ICD 9 and third IMD 15 and / or optionally with the third IMD. For example, the first electrical signal may be a subthreshold signal, a double pulse, or some other type of signal that is not typically delivered by ICD 9 unless ICD 9 is attempting to initiate communication with IPD 16 (or Figure 1A In some examples, the first electrical signal may not include a pacing pulse, but may include other types of signals. For example, the first electrical signal may include a configuration of a voltage signal or a current signal that is not otherwise useful for determining the impedance of the target tissue.

[0043] The IPD 16 may be implanted within the heart 26 of the patient 14. Figures 1A to 1C In an example of the present invention, the IPD 16 is implanted within the right ventricle of the heart 26 to sense the electrical activity of the heart 26 and deliver pacing therapy, e.g., ATP therapy, to the heart 26. The IPD 16 can be attached to the inner wall of the right ventricle of the heart 26 via one or more tissue-penetrating fixation elements. These fixation elements can secure the IPD 16 to the cardiac tissue and maintain contact between the electrodes (e.g., cathode or anode) and the cardiac tissue. However, in other examples, the system 8 may include an additional pacing device 16 located within a corresponding chamber of the heart 26 (e.g., the right atrium or left atrium and / or left ventricle). In another example, a cardiac pacemaker device of similar configuration to the IPD 16 can be attached to an external surface of the heart 26 (e.g., in contact with the epicardium) such that the pacing device is disposed outside the heart 26.

[0044] IPD 16 may be capable of sensing electrical signals using electrodes carried on the housing of IPD 16. These electrical signals may be electrical signals generated by the myocardium and indicate depolarization and repolarization of heart 26 at different times during the cardiac cycle. IPD 16 may also be capable of sensing electrical signals originating from ICD 9 that are delivered to heart 26, such as a therapy signal or a first electrical signal delivered by ICD 9 to heart 26 to notify IPD 16 that IPD 16 should initiate communication with ICD 9. This first electrical signal may be the only signal configured to notify IPD 16 that IPD 16 should initiate communication with ICD 9. To initiate communication, IPD 16 may communicate with ICD 9, such as by transmitting one or more pairing advertisements, such as Bluetooth pairing advertisements, to ICD 9, or IPD 16 may begin polling on its communication channel.

[0045] For example, the first electrical signal may be a signal that ICD 9 would not otherwise deliver to heart 26. Communication between IPD 16 and ICD 9 may be Bluetooth, tissue-conducted communication, or any other communication channel type that may additionally require channel monitoring for wake-up signals.

[0046] IPD 16 may analyze the sensed electrical signals to detect a tachyarrhythmia, such as ventricular tachycardia or ventricular fibrillation, or detect a first electrical signal delivered by ICD 9 to heart 26. In response to detecting the tachyarrhythmia, IPD 16 may, for example, begin delivering ATP therapy via electrodes of IPD 16, depending on the type of tachyarrhythmia. In response to detecting the first electrical signal, IPD 16 may initiate communication with ICD 9.

[0047] IPD 16 and ICD 9 can be configured to communicate with each other via a communication channel, for example, via radio frequency communication, conductive or conduction communication, or other types of communication, to collaborate with each other. For example, IPD 16 and ICD 9 can transmit information, such as sensed signals, accelerometer signals, and / or delivered signals, and can coordinate to establish pacing and / or sensing vectors between corresponding electrodes located on ICD 9, IPD 16, and / or leads 10. IPD 16 and ICD 9 can be configured for unidirectional or bidirectional communication. In some examples, ICD 9 may be configured to communicate with external device 21, while IPD 16 may not be configured to communicate with external device 21. In such examples, ICD 9 can act as an intermediary between external device 21 and IPD 16. For example, when external device 21 seeks to provide programming to IPD 16 or retrieve sensed information from it, external device 21 can do so through ICD 9. In this manner, IPD 16 does not need to use a communication channel to monitor for communication wake-up signals from external device 21.

[0048] In some examples, patient 14 may have more than two IMDs, such as a third IMD 15. For example, third IMD 15 may be an insertable cardiac monitor (ICM), a cardiac resynchronization therapy (CRT) system, a temporary ambulatory pacemaker (TAP), a neurostimulator, a cardiac assist device, etc. Third IMD 15, IPD 16, and ICD 9 may be configured to communicate with each other, for example, via radio frequency communication, conductive or conductance communication, or other types of communication, to cooperate with each other over a communication channel. For example, third IMD 15, IPD 16, and ICD 9 may transmit information, such as sensing signals, accelerometer signals, and / or delivered signals, and may coordinate to establish pacing and / or sensing vectors between corresponding electrodes located on ICD 9, IPD 16, third IMD 15, and / or lead 10. Third IMD 15, IPD 16, and ICD 9 may be configured for unidirectional or bidirectional communication.

[0049] In some examples, external device 21 includes a handheld computing device, a wearable device, a tablet computer, a laptop computer, a computer workstation, a networked computing device, or one or more servers. External device 21 may include a user interface that receives input from a user and provides information to the user, such as the instructions and alerts discussed herein. In some examples, a user may also interact with external device 21 remotely via a networked computing device. A user may interact with external device 21 to communicate with ICD 9 and / or IPD 16. For example, a user may interact with external device 21 to send query requests and retrieve therapy delivery data, update therapy parameters defining a therapy, manage communications between ICD 9 and / or IPD 16, or perform any other activity related to ICD 9 and / or IPD 16. In some examples, the user is a clinician, such as a physician, a technician, a surgeon, an electrophysiologist, or other healthcare professional. In some examples, the user may be patient 14, a family member of patient 14, a friend of patient 14, a caregiver of patient 14, or the like.

[0050] External device 21 may also allow a user to define how ICD 9 and / or IPD 16 sense electrical signals (e.g., ECG), detect arrhythmias such as tachyarrhythmias, deliver therapy, and communicate with other devices of system 8. For example, external device 21 may be used to change tachyarrhythmia detection parameters. In another example, external device 21 may be used to manage parameters defining a therapy such as ATP therapy. Additionally, external device 21 may be used to change the communication protocol between ICD 9 and IPD 16. For example, external device 21 may direct ICD 9 and / or IPD 16 to switch between one-way and two-way communication, and / or change which of ICD 9 and / or IPD 16 is responsible for the initial detection of an arrhythmia.

[0051] External device 21 may communicate with ICD 9 and / or IPD 16 via wireless communication using any technology known in the art. Examples of communication technology may include, for example, proprietary and non-proprietary radio frequency (RF) telemetry, although other technologies are also contemplated. In some examples, external device 21 may include a programming head that may be placed proximate to the body of patient 14 near the site of implantation of ICD 9 and / or IPD 16 to improve the quality or security of communication between ICD 9 and / or IPD 16 and external device 21.

[0052] In some examples, ICD 9 and IPD 16 may engage in communication with each other and / or with external device 21 to facilitate appropriate detection of cardiac events, delivery of cardiac therapies (such as anti-tachycardia therapy), and generation / transmission of indications about cardiac events. Anti-tachycardia therapy may include ATP. Communication may include one-way communication in which one device is configured to transmit communication messages and the other device is configured to receive those messages. Communication may instead include two-way communication in which each device is configured to transmit and receive communication messages. Although the following examples describe the detection of tachyarrhythmias and the delivery of ATP, ICD 9 and IPD 16 may be configured to communicate with each other and provide detection of other cardiac events (e.g., cardiac arrest, myocardial infarction, etc.) and deliver alternative electrical stimulation therapies. Additionally, ICD 9 and IPD 16 may be configured to communicate with each other and provide information about diagnosis, device status, or other information from the devices.

[0053] Lead and system as described herein can be used at least in part in the substernal space (for example, in the patient's anterior mediastinum) to provide a medical device system. An implanter (for example, a physician) can use any implantation tool of a plurality of implantation tools (for example, tunneling rods, sheaths or other tools that can traverse the illustrated attachments and form a tunnel in the substernal position) to implant the distal portion of the lead in the chest. For example, an implanter can make an incision near the center of the patient's trunk, for example, and introduce the implantation tool into the substernal position via the incision. The implantation tool is advanced upward from the incision along the rear of the sternum in the substernal position. The distal end of lead 10 is introduced into the tunnel via an implantation tool (for example, via a sheath). When the distal end of lead 10 advances through the substernal tunnel, the distal end of lead 10 is relatively straight. The undulating portion formed in advance or molded has enough flexibility to be straightened when the sheath or other lumens or channel routing lead 10 by the implantation tool. Once the distal end of lead 10 is in position, the implantation tool is withdrawn toward the incision and removed from the patient's body, while leaving lead 10 in position along the substernal path. When the implantation tool is withdrawn, the distal end of lead 10 assumes its pre-formed undulating configuration. Thus, when the implantation tool is withdrawn, the undulating configuration pushes electrodes 32a and 32b to the left side of the sternum compared to electrode segments 28a and 28b. As mentioned above, the implanter can align electrodes 32a and 32b along the anterior midline (or midsternal line) or the left sternal line (or left sternal lateral line).

[0054] While the techniques of this disclosure may be discussed with respect to system 8 as a whole or with respect to specific devices of system 8 , in some examples, the techniques of this disclosure may be performed by other devices, such as an ICM, a CRT system, a TAP, a neurostimulator, a cardiac assist device, etc. For example, the processing circuitry of one or more devices may cooperate to perform any of the techniques of this disclosure.

[0055] although Figures 1A to 1C is described in the context of an ICD 9 connected to leads 10 and an IPD 16, but the techniques may be applicable to other systems. For example, instead of or in addition to the ICD 9, the system may include a medical device that includes leads having a distal portion that is implanted above the sternum (or other extrathoracic, subcutaneous, or intercostal location) rather than below the ribs and / or sternum. As another example, instead of an intracardiac pacing device, a pacing system may be implanted that has a subcutaneous or submuscular pacemaker and one or more leads that are connected to the pacemaker and extend from the pacemaker to one or more chambers of the heart or attached to the outside of the heart to provide pacing therapy to one or more chambers. As another example, the system may have one or more insertable cardiac monitors, pressure sensing devices, neurostimulators, or other IMDs in place of or in addition to the ICD or IPD. Thus, Figures 1A to 1C The examples are shown for illustrative purposes only and should not be considered as limiting the techniques described herein.

[0056] Figure 2 It shows Figures 1A to 1C A conceptual diagram of an example configuration of an IPD 16 of a medical device system. Figure 2 As shown, IPD 16 includes housing 50, cover 58, electrode 60, electrode 52, securing mechanism 62, flange 54, and opening 56. Housing 50 and cover 58 can be collectively considered the housing of IPD 16. In this manner, housing 50 and cover 58 can enclose and protect the various electrical components within IPD 16. Housing 50 can enclose substantially all of the electrical components and, in some examples, one or more accelerometers, and cover 58 can seal housing 50 and create a hermetically sealed enclosure for IPD 16. Although IPD 16 is generally described as including one or more electrodes, IPD 16 may generally include at least two electrodes (e.g., electrodes 52 and 60) to deliver electrical signals (e.g., a therapy such as ATP) and / or provide at least one sensing vector.

[0057] Electrode 52 and electrode 60 are carried on a housing formed by housing 50 and cover 58. In this manner, electrodes 52 and 60 can be considered as leadless electrodes. Figure 2In the example of FIG, electrode 60 is placed on the outer surface of cover 58. Electrode 60 can be a circular electrode positioned to contact cardiac tissue when implanted. Electrode 52 can be an annular or cylindrical electrode placed on the outer surface of housing 50. Both housing 50 and cover 58 can be electrically insulated. Electrode 60 can be used as a cathode and electrode 52 can be used as an anode, or vice versa, for delivering pacing stimulation therapy such as ATP. However, electrodes 52 and 60 can be used in any stimulation configuration. In addition, electrodes 52 and 60 can be used to detect intrinsic electrical signals from the myocardium as well as a first electrical signal ( Figures 1A to 1C ), the first electrical signal is used to notify IPD 16 to initiate communication with ICD 9. In other examples, IPD 16 may include three or more electrodes, each of which can deliver therapy and / or detect both the intrinsic signal and the first electrical signal. Compared to alternative devices, the ATP delivered by IPD 16 may be considered "painless" to patient 14, or even imperceptible to patient 14, because the electrical stimulation occurs very close to or at the myocardium and at relatively low energy levels.

[0058] Fixation mechanism 62 can attach IPD 16 to cardiac tissue. Fixation mechanism 62 can be an active fixation fork, a screw, a clamp, an adhesive member, or any other type of device that attaches the device to tissue. Figure 2 As shown in the example of , the fixing mechanism 62 can be constructed of a memory material that maintains a pre-formed shape. During implantation, the fixing mechanism 62 can be bent forward to pierce the tissue and allowed to bend backward toward the housing 50. In this way, the fixing mechanism 62 can be embedded in the target tissue.

[0059] A flange 54 may be provided on one end of housing 50 to enable tethering or extraction of IPD 16. For example, sutures or other devices may be inserted around flange 54 and / or through opening 56 and attached to tissue. In this manner, if securing mechanism 62 fails, flange 54 may provide a secondary attachment structure to tether or retain IPD 16 within heart 18. Should the IPD need to be transplanted (or removed) from patient 14, flange 54 and / or opening 56 may also be used to extract IPD 16 if such action is deemed necessary.

[0060] The techniques described herein may generally be described with respect to a leadless pacing device, such as an IPD 16. The IPD 16 may be an example of an anti-tachycardia pacing device (ATPD). However, alternative implantable medical devices may be used to perform the same or similar functions as the IPD 16, e.g., delivering ATP or other therapies to the heart 26 and communicating with the ICD 9 and / or external device 21.

[0061] In another example, the ATPD can be configured to be implanted outside of heart 26, e.g., near or attached to the epicardium of heart 26. Electrodes carried by the ATPD housing can be placed in contact with the epicardium, and / or one or more electrodes coupled to the leads of the ATPD can be placed in contact with the epicardium at a location sufficient to provide therapy such as ATP (e.g., on the exterior surface of the left and / or right ventricle). In any example, subcutaneous ICD 9 can communicate with one or more leadless or leaded devices implanted inside or outside heart 26.

[0062] Figure 3 It shows Figures 1A to 1C and Figure 2 2 is a functional block diagram of an example configuration of an IPD 16. In the illustrated example, the IPD 16 includes processing circuitry 264, memory 226, electrical signal generating circuitry 270, sensing circuitry 272, communication circuitry 268, motion sensor 278 (which may include one or more accelerometers), and power supply 274. The electronic components may receive power from power supply 274, which may be a rechargeable or non-rechargeable battery. In other examples, the IPD 16 may include more or fewer electronic components. The described circuitry may be implemented together on common hardware components or separately as discrete but interoperable hardware or software components. The description of different features of the circuitry is intended to highlight different functional aspects and does not necessarily imply that such circuitry must be implemented by separate hardware or software components. Instead, the functions associated with one or more circuitry may be performed by separate hardware or software components, or integrated within common or separate hardware or software components.

[0063] The memory 226 includes computer-readable instructions that, when executed by the processing circuitry 264, cause the IPD 16 and the processing circuitry 264 to perform the various functions attributed to the IPD 16 and the processing circuitry 264 herein (e.g., determining a cardiac event, determining a fall, a hunched posture, or a change from an upright posture to a non-upright posture, delivering therapy, and / or generating an indication for output). The memory 226 may include any volatile memory, non-volatile memory, magnetic memory, optical memory, or dielectric memory, such as random access memory (RAM), ferroelectric RAM (FRAM), read-only memory (ROM), non-volatile RAM (NVRAM), electrically erasable programmable ROM (EEPROM), flash memory, or any other digital or analog medium.

[0064] Processing circuitry 264 may include any one or more of a microprocessor, a controller, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or equivalent discrete or analog logic circuitry. In some examples, processing circuitry 264 may include multiple components (such as any combination of one or more microprocessors, one or more controllers, one or more DSPs, one or more ASICs, or one or more FPGAs) and other discrete or integrated logic circuitry. The functionality attributed herein to processing circuitry 264 may be embodied in software, firmware, hardware, or any combination thereof.

[0065] The electrical signal generating circuitry 270 is electrically coupled to the electrodes 52 and 60 carried on the housing of the IPD 16. The electrical signal generating circuitry 270 may include one or more pulse generators, capacitors, and / or other components capable of generating and / or storing energy for delivery as pacing therapy. In the example shown, the electrical signal generating circuitry 270 is configured to generate and deliver electrical stimulation therapy to the heart 26. For example, the electrical signal generating circuitry 270 may deliver electrical stimulation therapy to a portion of the myocardium within the heart 26 via the electrodes 52 and 60. In some examples, the electrical signal generating circuitry 270 may deliver pacing stimulation in the form of voltage or current electrical pulses, e.g., ATP therapy. In other examples, the electrical signal generating circuitry 270 may deliver stimulation in the form of other signals, such as sine waves, square waves, and / or other substantially continuous time signals.

[0066] Motion sensor 278 may include a three-axis accelerometer, one or more single-axis accelerometers, etc. Motion sensor 278 may be configured to generate one or more signals that may be indicative of the posture or activity of patient 14 .

[0067] Processing circuitry 264 may monitor signals from heart 26 via sensing circuitry 272. For example, processing circuitry 264 may monitor heart 26 for electrical signals, including a first electrical signal originating from ICD 9 being delivered to heart 26, which may indicate that ICD 9 desires to initiate communication with IPD 16. In response to detecting the delivery of the first electrical signal from ICD 9 to heart 26, processing circuitry 264 may control communication circuitry 268 to initiate communication with ICD 9. In this way, IPD 16 may monitor for a communication wake-up signal on the same sensing circuitry that is powered to monitor physiological signals, thereby eliminating the need to power the communication circuitry to monitor for a wake-up signal on a separate communication channel.

[0068] In some examples, IPD 16 may include a safe mode that processing circuitry 264 may enter to avoid attempting to initiate communication with ICD 9. For example, it may be desirable to use the safe mode when IPD 16 may sense a signal similar to the first electrical signal when ICD 9 may not be delivering the first electrical signal to heart 26, such as when patient 14 may be within a magnetic resonance imaging (MRI) machine.

[0069] Processing circuitry 264 may control electrical signal generation circuitry 270 to deliver cardiac pacing therapy or other therapy to heart 26 according to parameters that may be stored in parameters 276. For example, processing circuitry 264 may control electrical signal generation circuitry 270 to deliver pacing pulses at an amplitude, pulse width, frequency, or electrode polarity specified by therapy parameters, including intervals defining under what conditions and when pacing pulses should be delivered. In this manner, electrical signal generation circuitry 270 may deliver pacing pulses (e.g., ATP pulses) to heart 26 via electrodes 52 and 60. Although IPD 16 may include only two electrodes, e.g., electrodes 52 and 60, in other examples, IPD 16 may utilize three or more electrodes. IPD 16 may use any combination of electrodes to deliver therapy and / or detect electrical signals from patient 14.

[0070] Processing circuitry 264 can control electrical signal generation circuitry 270 to deliver pacing pulses for ATP therapy based on ATP parameters stored in parameters 276 in memory 266. ATP therapy parameters may include pulse interval, pulse width, current and / or voltage amplitude, and duration of each pacing mode. In some examples, the ATP parameters may include a plurality of propagation time ranges and associated pulse numbers for an ATP train, a formula applicable to a first propagation time, a linear equation applicable to a first propagation time, a continuous function applicable to a first propagation time, or a lookup table that may include associated pulse numbers for a first propagation time and an ATP train. For example, the pulse interval may be based on a fraction of the detected ventricular tachycardia cycle length and be between approximately 150 milliseconds and 500 milliseconds (e.g., between approximately 2.0 Hz and 7.0 Hz), and the pulse width may be between approximately 0.5 milliseconds and 2.0 milliseconds. The amplitude of each pacing pulse may be between approximately 2.0 volts and 10.0 volts. In some examples, the pulse amplitude may be approximately 6.0 V and the pulse width may be approximately 1.5 milliseconds; another example may include a pulse amplitude of approximately 5.0 V and a pulse width of approximately 1.0 milliseconds.

[0071] Each pulse train during ATP may last for a duration between about 70 milliseconds and about 15 seconds, or may be defined as a specific number of pulses.

[0072] Processing circuitry 264 controls electrical signal generation circuitry 270 to generate and deliver pacing pulses having any of a variety of shapes, amplitudes, pulse widths, or other characteristics to capture the heart. For example, pacing pulses can be monophasic, biphasic, or multiphasic (e.g., having more than two phases). When delivering pacing pulses, the pacing threshold of the heart can depend on a variety of factors, including the position, type, size, orientation, and / or spacing of IPD 16 and / or electrodes 52 and / or 60, physical abnormalities of the heart (e.g., pericardial adhesions or myocardial infarction), or other factors.

[0073] In examples where IPD 16 includes more than two electrodes, electrical signal generation circuitry 270 may include a switch, and processing circuitry 264 may use the switch to select which of the available electrodes to use for delivery of pacing pulses (e.g., via a data / address bus). The switch may include a switch array, a switch matrix, a multiplexer, or any other type of switching device suitable for selectively coupling stimulation energy to selected electrodes.

[0074] The sensing circuit system 272 is electrically connected to some or all of the electrodes 52 and 60 and monitors signals from some or all of these electrodes to monitor the electrical activity, impedance, or other electrical phenomena of the heart 26, including monitoring the first electrical signal from the ICD 9. Sensing can be performed to determine heart rate or heart rate variability or detect arrhythmias (e.g., tachyarrhythmias or bradycardias) or other electrical signals, such as the first electrical signal. The sensing circuit system 272 can also include a switch to select which of the available electrodes (or electrode polarities) to use to sense cardiac activity based on which electrode combination or electrode vector is used in the current sensing configuration. In an example with several electrodes, the processing circuit system 264 can select the electrodes to be used as sensing electrodes via a switch circuit system located within the sensing circuit system 272. The sensing circuit system 272 can include one or more detection channels, each of which can be coupled to a selected electrode configuration to detect cardiac signals through the electrode configuration. Some detection channels may be configured to detect cardiac events, such as a fiducial, a QRS complex, a P wave, or an R wave, and provide an indication of the occurrence of such an event to processing circuitry 264. Processing circuitry 264 may control the functions of sensing circuitry 272 by providing signals via a data / address bus.

[0075] The components of the sensing circuit system 272 may be analog components, digital components, or a combination thereof. The sensing circuit system 272 may, for example, include one or more sense amplifiers, filters, rectifiers, threshold detectors, analog-to-digital converters (ADCs), and the like. The sensing circuit system 272 may convert the sensed signal into digital form and provide the digital signal to the processing circuit system 264 for processing or analysis. For example, the sensing circuit system 272 may amplify the signal from the sensing electrode and convert the amplified signal into a multi-bit digital signal via the ADC. The sensing circuit system 272 may also compare the processed signal with a threshold value to detect the presence of atrial or ventricular depolarization (e.g., a P wave or an R wave) and indicate the presence of atrial depolarization (e.g., a P wave) or ventricular depolarization (e.g., an R wave) to the processing circuit system 264.

[0076] Sensing circuitry 272 and / or processing circuitry 264 may also include circuitry for measuring a capture threshold for delivering pacing pulses via electrodes 52 and 60. The capture threshold may indicate the voltage and pulse width required to induce depolarization of the surrounding myocardium. For example, processing circuitry 264 may periodically control electrical signal generation circuitry 270 to modify the amplitude of pacing pulses delivered to patient 14, and sensing circuitry 272 and / or processing circuitry 264 may detect whether the surrounding cardiac tissue is depolarized in response to the pacing pulses, i.e., detect whether there is an induced response to the pacing pulses. Processing circuitry 264 may determine the capture threshold based on the amplitude at which loss of capture occurs.

[0077] The processing circuit system 264 can process signals from the sensing circuit system 272 to monitor the electrical activity of the patient's heart and monitor the first electrical signal. For example, the processing circuit system can monitor the signal sensed by the sensing circuit system 272, and the ICD 9 can deliver the signal to the anatomical structure of the patient 14, which can be different from the normal therapy that can be delivered by the ICD 9, such as a subthreshold signal, a double pulse, etc. The processing circuit system 264 can store the signal obtained by the sensing circuit system 272 and any generated ECG waveform, marker channel data, or other data derived based on the sensed signal in the memory 266. The processing circuit system 264 can analyze the ECG waveform and / or marker channel data to detect a cardiac event (e.g., tachycardia). In response to detecting a cardiac event, the processing circuit system 264 can control the electrical signal generation circuit system 270 to deliver the desired therapy to treat the cardiac event, for example, ATP therapy.

[0078] In examples where the IPD 16 includes more than two electrodes, the electrical signal generation circuitry 270 may include a switch, and the processing circuitry 264 may use the switch to select which of the available electrodes to use for delivering pacing pulses (e.g., via a data / address bus). The switch may include a switch array, a switch matrix, a multiplexer, or any other type of switching device suitable for selectively coupling stimulation energy to selected electrodes. The processing circuitry 264 may select an electrode to serve as a signal electrode or signal vector via the switching circuitry located within the electrical signal generation circuitry 270. In some cases, the same switching circuitry may be used by both the electrical signal generation circuitry 270 and the sensing circuitry 272. In other cases, each of the sensing circuitry 272 and the electrical signal generation circuitry 270 may have separate switching circuitry.

[0079] Processing circuitry 264 may include timing and control circuitry, which may be embodied in hardware, firmware, software, or any combination thereof. The timing and control circuitry may include dedicated hardware circuitry (such as an ASIC) separate from other processing circuitry 264 components, such as a microprocessor, or a software module executed by a component of processing circuitry 264, which may be a microprocessor or ASIC. The timing and control circuitry may implement a programmable counter. If IPD 16 is configured to generate and deliver pacing pulses to heart 26, such a counter may control the basic time intervals associated with DDD, VVI, DVI, VDD, AAI, DDI, DDDR, VVIR, DVIR, VDDR, AAIR, DDIR, and other pacing modes.

[0080] The intervals defined by the timing and control circuitry within processing circuitry 264 may include atrial and ventricular pacing escape intervals, a refractory period during which sensed P and R waves are ineffective for re-starting the timing of the escape interval, and the pulse width of the pacing pulse. As another example, the timing and control circuitry may inhibit sensing from one or more channels of sensing circuitry 272 during time intervals during and after delivery of electrical stimulation to heart 26. The duration of these intervals may be determined by processing circuitry 264 in response to data stored in memory 226. The timing and control circuitry of processing circuitry 264 may also determine the amplitude of the cardiac pacing pulses.

[0081] Upon sensing R-waves and P-waves using the detection channels of sensing circuitry 272, an interval counter implemented by the timing and control circuitry of processing circuitry 264 may be reset. In examples where IPD 16 provides pacing, electrical signal generation circuitry 270 may include pacemaker output circuitry coupled to electrodes 52 and 60, for example, adapted to deliver bipolar or unipolar pacing pulses to one of the chambers of heart 26. In such examples, processing circuitry 264 may reset the interval counter upon generation of pacing pulses by electrical signal generation circuitry 270, thereby controlling the basic timing of cardiac pacing functions, including ATP or post-shock pacing.

[0082] When reset by the sensed R and P waves, the count values ​​present in the interval counters can be used by processing circuitry 264 to measure the duration of the RR interval, PP interval, PR interval, and RP interval, which are measurements that can be stored in memory 266. Processing circuitry 264 can use the counts in the interval counters to detect tachyarrhythmia events, such as atrial fibrillation, atrial tachycardia, ventricular fibrillation, or ventricular tachycardia. These intervals can also be used to detect overall heart rate, ventricular contraction rate, and heart rate variability. A portion of memory 266 can be configured as a plurality of recirculating buffers that can hold a series of measured intervals that can be analyzed by processing circuitry 264 in response to the occurrence of a pacing or sensing interruption to determine whether the patient's heart 26 is currently exhibiting an atrial or ventricular tachyarrhythmia. In some examples, the arrhythmia detection method may include any suitable tachyarrhythmia detection algorithm.

[0083] In some examples, processing circuitry 264 can determine that a tachyarrhythmia has occurred by identifying a shortened RR (or PP) interval length. Typically, processing circuitry 264 detects tachycardia when the interval length is less than 220 milliseconds and fibrillation when the interval length is less than 180 milliseconds. In other examples, processing circuitry 264 can detect ventricular tachycardia when the interval length is between 3 and 30 milliseconds and detect ventricular fibrillation when the interval length is less than 240 milliseconds. These interval lengths are merely examples, and the user can define the interval length as needed, which can then be stored in memory 266. As an example, this interval length may need to be detected for a specific number of consecutive cycles, for a specific percentage of cycles within an operating window, or for a running average of a specific number of cardiac cycles. In other examples, additional physiological parameters may be used to detect arrhythmias. For example, processing circuitry 264 can analyze one or more morphological measurements, impedance, or any other physiological measurements to determine whether patient 14 is experiencing a tachyarrhythmia.

[0084] Where an ATP regimen is desired, timed intervals for controlling the generation of ATP therapy by therapy delivery circuitry 270 may be loaded into the timing and control circuitry by processing circuitry 264 based on ATP parameters 276 to control the operation of an escape interval counter therein and to define a refractory period during which detection of R waves and P waves is ineffective for restarting the escape interval counter for ATP. An ATP regimen may be desired if processing circuitry 264 detects an atrial or ventricular tachycardia based on signals from sensing circuitry 272 and / or receives a command from another device or system, such as an ICD 9.

[0085] In addition to detecting and identifying a particular type of cardiac rhythm and first electrical signal, the sensing circuit system 272 may also sample the detected intrinsic signal to generate an ECG or other time-based indication of a cardiac event. The processing circuit system 264 may also be capable of coordinating the delivery of pacing pulses from different IPDs implanted in different chambers of the heart 26 (such as an IPD implanted in the atrium and / or an IPD implanted in the left ventricle). For example, the processing circuit system 264 may identify delivered pulses from other IPDs via the sensing circuit system 272 and update the pulse timing to complete the selected pacing scheme. This detection may be on a pulse-to-pulse or beat-to-beat basis or on a less frequent basis to slightly modify the pulse rate over time. In other examples, the IPDs may communicate with each other via the communication circuit system 268 and / or transmit instructions via a carrier wave (such as a stimulation waveform). In this way, ATP pacing can be coordinated from multiple IPDs.

[0086] IPD 16 can deliver ATP therapy using electrodes 52 and 60 and electrical signal generation circuitry 270, and can sense a local evoked response using electrodes 52 and 60 and sensing circuitry 272 at a location at or near the location where the ATP therapy is delivered. Another device (such as ICD 9) can sense an evoked response to ATP pacing delivered by IPD 16 by sensing at a location significantly remote from the location where the ATP therapy is delivered. In other examples, the same device using different electrode vectors can be used to sense both local and global evoked responses to the delivered ATP therapy delivered by the device. Similar to R-waves, evoked responses can be detected via hardware of sensing circuitry 272 (e.g., using a sense amplifier to detect an amplitude above a threshold shortly after delivery of the pacing pulse) and / or can be detected by processing circuitry 264 by signal processing a digitized version of the ECG from electrodes 52 and 60 to determine spikes.

[0087] The memory 266 may be configured to store various operating parameters, therapy parameters including ATP therapy parameters, sensed and detected data, and any other information related to the therapy and treatment of the patient 14. Figure 5 In the example of FIG2 , memory 266 may store sensed ECG, detected arrhythmias, communications from ICD 9 and / or external device 21, and therapy parameters defining ATP therapy (which may be stored in parameters 276). In other examples, memory 266 may serve as a temporary buffer for storing data until it can be uploaded to ICD 9, another implanted device, or external device 21.

[0088] The communication circuit system 268 includes a circuit for communicating with an external device such as 21 ( Figures 1A to 1C and Figure 7 )、ICD 9( Figures 1A to 1C and Figure 6 ), a clinician programmer, a patient monitoring device, or the like. For example, communication circuitry 284 may include appropriate modulation, demodulation, frequency conversion, filtering, and amplifier components for transmitting and receiving data via antenna 269. Antenna 269 may be located within the connector block of IPD 16 or within the housing of IPD 16. Under the control of processing circuitry 264, communication circuitry 268 may receive downlink telemetry from and transmit uplink telemetry to external device 21 and / or ICD 9 via antenna 269, which may be internal and / or external. Processing circuitry 264 may provide data to be uplinked to external device 21 and / or ICD 9 and control signals for telemetry circuitry within communication circuitry 268, for example, via an address / data bus. In some examples, communication circuitry 268 may provide received data to processing circuitry 264 via a multiplexer.

[0089] In some examples, IPD 16 may signal external device 21 and / or ICD 9 to further communicate with and deliver alerts through a network, such as a Medtronic Networks developed by Medtronic plc., of Dublin, Ireland. network or some other network that links the patient 14 to the clinician. The IPD 16 may transmit information to the network either spontaneously or in response to an interrogation request from a user.

[0090] Power supply 274 may be any type of device configured to hold an electrical charge to operate the circuitry of IPD 16. Power supply 274 may be provided as a rechargeable or non-rechargeable battery. In other examples, power supply 274 may incorporate an energy scavenging system that stores electrical energy from movement of IPD 16 within patient 14.

[0091] The various circuit systems of IPD 16 may include any one or more processors, controllers, digital signal processors (DSPs), application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), or equivalent discrete or integrated circuit systems, including analog circuit systems, digital circuit systems, or logic circuit systems.

[0092] According to the techniques of the present disclosure, processing circuitry 264 may receive a signal from at least one of a sensor or sensing circuitry (e.g., electrodes 52 and 60, and / or sensing circuitry 272) indicating delivery of a first electrical signal by another medical device (e.g., ICD 9) to an anatomical structure of patient 14. Processing circuitry 264 may control communication circuitry 268 to initiate communication with the other medical device based on receiving the signal indicating delivery of the first electrical signal. For example, to initiate communication with the other medical device, processing circuitry 264 may control communication circuitry 268 to communicate with the other medical device, such as transmitting one or more pairing advertisements, such as Bluetooth pairing advertisements, or polling a communication channel.

[0093] In some examples, processing circuitry 264 may receive and respond to instructions from another device via communication circuitry 268. For example, the instructions may include instructions to start delivering therapy (e.g., ATP therapy, pacing therapy, shock, etc.), stop delivering therapy, and / or configure the operation of IPD 16 (such as reprogramming IPD 16).

[0094] Figure 4 It shows Figures 1A to 1C2 is a functional block diagram of an example configuration of an ICD 9 of an implantable medical device system. In the example shown, the ICD 9 includes processing circuitry 280, sensing circuitry 286, electrical signal generating circuitry 288, communication circuitry 284, motion sensor 298 (which may include one or more accelerometers), and memory 282. The electronic components may receive power from a power source 290, which may be a rechargeable or non-rechargeable battery. In other examples, the ICD 9 may include more or fewer electronic components. The described circuit systems may be implemented together on common hardware components or separately as discrete but interoperable hardware or software components. The descriptions of different features of the circuit systems are intended to highlight different functional aspects and do not necessarily imply that such circuit systems must be implemented by separate hardware or software components. Rather, the functions associated with one or more circuit systems may be performed by separate hardware or software components, or integrated within common or separate hardware or software components. For exemplary purposes only, Figure 4 It will be described in the context of ICD 9 being coupled to lead 10. However, ICD 9 may also be coupled to other leads, and thus to other electrodes.

[0095] Memory 282 includes computer-readable instructions that, when executed by processing circuitry 280, cause ICD 9 and processing circuitry 280 to perform various functions attributed to ICD 9 and processing circuitry 280 herein (e.g., detecting cardiac events, delivering cardiac therapies such as anti-tachycardia pacing, and / or generating / transmitting indications regarding cardiac events). Memory 282 may include any volatile, non-volatile, magnetic, optical, or electronic media, such as RAM, ROM, FRAM, NVRAM, EEPROM, flash memory, or any other digital or analog media.

[0096] Sensing circuitry 286 may be electrically coupled to electrode 28 (or, individually, segments 28a and / or 28b) and some or all of 32a and 32b (eg, electrodes 28a and 28b) via conductors of lead 10 and one or more electrical feedthroughs. Figures 1A to 1C ), or electrically coupled to the housing electrodes via conductors located inside the housing of the ICD 9. Sensing circuitry 286 is configured to obtain signals sensed via one or more combinations of electrodes 28 (or, individually, segments 28a and / or 28b), 32a, 32b, and the housing electrodes of the ICD 9, and to process the obtained signals.

[0097] The components of the sensing circuit system 286 may be analog components, digital components, or a combination thereof. The sensing circuit system 286 may, for example, include one or more sense amplifiers, filters, rectifiers, threshold detectors, ADCs, and the like. The sensing circuit system 286 may convert the sensed signal into digital form and provide the digital signal to the processing circuit system 280 for processing or analysis. For example, the sensing circuit system 286 may amplify the signal from the sensing electrode and convert the amplified signal into a multi-bit digital signal via the ADC. The sensing circuit system 286 may also compare the processed signal with a threshold value to detect the presence of a fiducial point, a QRS complex, and atrial or ventricular depolarization (e.g., a P wave or an R wave) and indicate the presence of atrial depolarization (e.g., a P wave) or ventricular depolarization (e.g., an R wave) to the processing circuit system 280.

[0098] Processing circuitry 280 may include any one or more of a microprocessor, a controller, a DSP, an ASIC, an FPGA, or equivalent discrete or analog logic circuitry. In some examples, processing circuitry 280 may include multiple components (such as any combination of one or more microprocessors, one or more controllers, one or more DSPs, one or more ASICs, or one or more FPGAs) and other discrete or integrated logic circuitry. The functionality attributed herein to processing circuitry 280 may be embodied in software, firmware, hardware, or any combination thereof.

[0099] The processing circuit system 280 can process the signals from the sensing circuit system 286 to monitor the electrical activity of the patient's heart. The processing circuit system 280 can store the signals obtained by the sensing circuit system 286 and any generated ECG waveforms, marker channel data, accelerometer data, or other data derived based on the sensed signals in the memory 282. The processing circuit system 280 can analyze the ECG waveforms and / or marker channel data to detect cardiac events (e.g., tachycardia). In response to detecting a cardiac event, the processing circuit system 280 can control the electrical signal generation circuit system 288 to deliver the desired therapy to treat the cardiac event, for example, ATP therapy and / or anti-tachyarrhythmia (e.g., defibrillation or cardioversion) shock.

[0100] The electrical signal generation circuit system 288 is configured to generate and deliver electrical therapy to the heart. The electrical signal generation circuit system 288 may include one or more pulse generators, capacitors, and / or other components capable of generating and / or storing energy for delivery as pacing therapy, defibrillation therapy, cardioversion therapy, cardiac resynchronization therapy, other therapy, or a combination of therapies. In some cases, the electrical signal generation circuit system 288 may include a first set of components configured to provide pacing therapy and a second set of components configured to provide defibrillation therapy. In other cases, the electrical signal generation circuit system 288 may utilize the same set of components to provide both pacing therapy and defibrillation therapy. In still other cases, the electrical signal generation circuit system 288 may share some of the defibrillation and pacing therapy components, while using other components only for defibrillation or pacing. In some examples, the electrical signal generation circuit system 288 may deliver pacing stimulation in the form of voltage or current electrical pulses, for example, ATP therapy. In other examples, electrical signal generation circuitry 288 may deliver stimulation in the form of other signals, such as sine waves, square waves, and / or other substantially continuous time signals.

[0101] The electrical signal generation circuitry 288 is also configured to deliver a first electrical signal, such as a pacing signal, that is used to notify another device (such as the IPD 16) to initiate communication with the ICD 9. This first electrical signal can be delivered, for example, to the heart 26 or other anatomical structure that the other device can monitor. For example, the ICD 9 can send a first electrical signal to the anatomical structure of the patient 14 via the electrical signal generation circuitry 288, rather than sending a wake-up signal via the communication circuitry 284 to initiate communication with the IPD 16. In some examples, the first electrical signal includes a subthreshold signal. In some examples, the first electrical signal includes a double pulse (e.g., two pacing pulses). In some examples, the first electrical signal is a signal that is not used for any purpose other than indicating to the other device that the other device should initiate communication with the ICD 9. In this way, the IPD 16 does not need to monitor the wake-up signal on the communication channel, thereby saving power. Instead, the IPD 16 utilizes other sensors or sensing circuitry that are already powered to monitor physiological signals.

[0102] Motion sensor 298 may include a three-axis accelerometer, one or more single-axis accelerometers, etc. Motion sensor 298 may be configured to generate one or more signals that may be indicative of the posture or activity of patient 14 .

[0103] The processing circuit system 280 can control the electrical signal generation circuit system 288 to deliver the generated therapy or first electrical signal to the heart via one or more combinations of electrodes 28 (or individually, segments 28a and / or 28b), 32a, and 32b of lead 10, and the housing electrodes of ICD 9 according to one or more therapy programs that can be stored in memory 282. Other electrodes can be utilized if the processing circuit system 280 is coupled to different leads. The processing circuit system 280 controls the electrical signal generation circuit system 288 to generate electrical stimulation therapy having an amplitude, pulse width, timing, frequency, electrode combination, or electrode configuration specified by the stored therapy program.

[0104] Processing circuitry 280 controls electrical signal generation circuitry 288 to deliver cardiac pacing therapy, or a first electrical signal, to heart 26 according to parameters that may be stored in parameters 294 of memory 282. For example, processing circuitry 280 may control electrical signal generation circuitry 288 to deliver pacing pulses at an amplitude, pulse width, frequency, or electrode polarity specified by the therapy parameters, including intervals defining under what conditions and when pacing pulses should be delivered.

[0105] Processing circuitry 280 may control electrical signal generation circuitry 288 to deliver therapy, such as ATP therapy, an anti-tachyarrhythmia shock, such as defibrillation or cardioversion, etc. Processing circuitry 280 may also control electrical signal generation circuitry 288 to deliver a first electrical signal to the anatomy of patient 14 according to other parameters, which may be stored in parameters 294. The first electrical signal may be a signal that electrical signal generation circuitry 288 may deliver only when processing circuitry 280 attempts to initiate communication with IPD 16.

[0106] The electrical signal generation circuitry 288 may include switching circuitry to select which available electrode is used to deliver therapy. The switching circuitry may include a switch array, a switch matrix, a multiplexer, or any other type of switching device suitable for selectively coupling electrodes to the electrical signal generation circuitry 288. The processing circuitry 280 may select an electrode to serve as a signal electrode or signal vector via the switching circuitry located within the electrical signal generation circuitry 288. Where the defibrillation segments 28a and 28b are each coupled to separate conductors, the processing circuitry 280 may be configured to selectively couple the electrical signal generation circuitry 288 to either or both segments 28a and 28b. In some cases, the same switching circuitry may be used by both the electrical signal generation circuitry 288 and the sensing circuitry 286. In other cases, each of the sensing circuitry 286 and the electrical signal generation circuitry 288 may have separate switching circuitry.

[0107] According to the techniques of this disclosure, processing circuitry 280 can control electrical signal generation circuitry to deliver a first electrical signal to the patient's anatomy. Processing circuitry 280 can communicate with another medical device via communication circuitry based on the electrical signal generation circuitry delivering the first electrical signal.

[0108] In one example, the electrical signal generation circuitry 288 can deliver pacing via an electrode vector that includes one or both defibrillation electrode segments 28a and 28b. The electrode vector used for pacing can be segment 28a as the anode (or cathode) and segment 28b or one of the electrodes 32a or 32b or the housing of the ICD 9 as the cathode (or anode), or segment 28b as the anode (or cathode) and segment 28b or one of the electrodes 32a or 32b or the housing of the ICD 9 as the cathode (or anode). In some examples, electrodes 52 and / or electrodes 60 of the IPD 16 can serve as the anode or cathode, and the ICD 9 can communicate with the IPD 16 via the communication circuitry 284, and / or an external device can communicate with the ICD 9 and IPD 16 to coordinate the use of electrodes of both the ICD 9 and IPD 16.

[0109] The processing circuitry 280 controls the electrical signal generation circuitry 288 to generate and deliver pacing pulses having any one of a plurality of shapes, amplitudes, pulse widths, or other characteristics to capture the heart. For example, the pacing pulses may be monophasic, biphasic, or polyphasic (e.g., having more than two phases). When pacing pulses are delivered from the substernal space (e.g., from electrodes 32a, 32b and / or electrode segments 28a and / or 28b substantially within the anterior mediastinum 36), the pacing thresholds of the heart may depend on a number of factors, including the location, type, size, orientation, and / or spacing of the electrodes 32a and 32b and / or electrode segments 28a and 28b, the position of the ICD 9 relative to the electrodes 32a and 32b and / or electrode segments 28a and 28b, a physical abnormality of the heart (e.g., pericardial adhesions or myocardial infarction), or other factors.

[0110] Processing circuitry 280 may include timing and control circuitry, which may be embodied in hardware, firmware, software, or any combination thereof. The timing and control circuitry may include dedicated hardware circuitry (such as an ASIC) separate from other processing circuitry 280 components, such as a microprocessor, or a software module executed by a component of processing circuitry 280, which may be a microprocessor or ASIC. The timing and control circuitry may implement a programmable counter. If ICD 9 is configured to generate and deliver pacing pulses to heart 26, such a counter may control the basic time intervals associated with DDD, VVI, DVI, VDD, AAI, DDI, DDDR, VVIR, DVIR, VDDR, AAIR, DDIR, and other pacing modes.

[0111] The intervals defined by the timing and control circuitry within processing circuitry 280 may include atrial and ventricular pacing escape intervals, refractory periods during which sensed P and R waves are ineffective for re-starting the timing of the escape interval, and pulse widths of pacing pulses. As another example, the timing and control circuitry may inhibit sensing from one or more channels of sensing circuitry 286 during time intervals during and after delivery of electrical stimulation to heart 26. The durations of these intervals may be determined by processing circuitry 264 in response to data stored in memory 282. The timing and control circuitry of processing circuitry 264 may also determine the amplitude of the cardiac pacing pulses.

[0112] Upon sensing R-waves and P-waves using the detection channels of sensing circuitry 286, an interval counter implemented by the timing and control circuitry of processing circuitry 280 may be reset. In examples where ICD 9 provides pacing, electrical signal generation circuitry 288 may include pacemaker output circuitry coupled to, for example, electrodes suitable for delivering bipolar or unipolar pacing pulses to one of the chambers of heart 26. In such examples, processing circuitry 280 may reset the interval counter upon generating pacing pulses via electrical signal generation circuitry 288, thereby controlling the basic timing of cardiac pacing functions, including ATP or post-shock pacing.

[0113] When reset by the sensed R and P waves, the count values ​​present in the interval counters can be used by processing circuitry 280 to measure the duration of the RR intervals, PP intervals, PR intervals, and RP intervals, which are measurements that can be stored in memory 282. Processing circuitry 280 can use the counts in the interval counters to detect tachyarrhythmic events, such as atrial fibrillation, atrial tachycardia, ventricular fibrillation, or ventricular tachycardia. These intervals can also be used to detect overall heart rate, ventricular contraction rate, and heart rate variability. A portion of memory 282 can be configured as a plurality of recirculating buffers that can hold a series of measured intervals that can be analyzed by processing circuitry 280 in response to the occurrence of a pacing or sensing interruption to determine whether the patient's heart 26 is currently exhibiting an atrial or ventricular tachyarrhythmia.

[0114] In some examples, the arrhythmia detection method may include any suitable tachyarrhythmia detection algorithm. In some examples, processing circuitry 280 may determine that a tachyarrhythmia has occurred by identifying a shortened RR (or PP) interval length. Typically, processing circuitry 280 detects tachycardia when the interval length is less than 220 milliseconds and detects fibrillation when the interval length is less than 180 milliseconds. In other examples, processing circuitry 280 may detect ventricular tachycardia when the interval length is between 3 and 30 milliseconds and detect ventricular fibrillation when the interval length is less than 240 milliseconds. These interval lengths are examples only, and the user may define the interval lengths as needed, which may then be stored in memory 282. By way of example, the interval length may need to be detected for a specific number of consecutive cycles, for a specific percentage of cycles within an operating window, or for a running average of a specific number of cardiac cycles. In other examples, additional physiological parameters may be used to detect arrhythmias. For example, processing circuitry 280 may analyze one or more morphological measurements, impedance measurements, or any other physiological measurements to determine whether patient 14 is experiencing a tachyarrhythmia.

[0115] Where an ATP regimen is desired, timed intervals for controlling the generation of ATP therapy by therapy delivery circuitry 288 may be loaded into the timing and control circuitry by processing circuitry 280 based on ATP parameters in parameters 294 to control the operation of the escape interval counter therein and to define a refractory period during which detection of R waves and P waves is ineffective for restarting the escape interval counter for ATP. An ATP regimen may be desired if processing circuitry 280 detects an atrial or ventricular tachycardia based on signals from sensing circuitry 286 and / or receives a command from another device or system, such as IPD 16.

[0116] The memory 282 may be configured to store various operating parameters, therapy parameters including ATP therapy parameters, sensed and detected data, and any other information related to the therapy and treatment of the patient 14. Figure 4 In the example of FIG, memory 282 may store sensed ECG, detected arrhythmias, communications from IPD 16, and therapy parameters defining ATP therapy (which may be stored in parameters 294). In other examples, memory 282 may serve as a temporary buffer for storing data until it can be uploaded to IPD 16, another implanted device, or external device 21.

[0117] The communication circuit system 284 includes a circuit for communicating with an external device such as 21 ( Figures 1A to 1C and Figure 7 )、IPD 16( Figures 1A to 1C and Figure 2 ), a clinician programmer, a patient monitoring device, or the like. For example, communication circuitry 284 may include appropriate modulation, demodulation, frequency conversion, filtering, and amplifier components for transmitting and receiving data via antenna 292. Antenna 292 may be located within the connector block of ICD 9 or within the housing of ICD 9. Under the control of processing circuitry 280, communication circuitry 284 may receive downlink telemetry from external device 21 and / or IPD 16 and transmit uplink telemetry to the external device via antenna 292, which may be internal and / or external. Processing circuitry 280 may provide data to be uplinked to external device 21 and / or IPD 16 and control signals for telemetry circuitry within communication circuitry 284, for example, via an address / data bus. In some examples, communication circuitry 284 may provide received data to processing circuitry 280 via a multiplexer.

[0118] In some examples, the ICD 9 may signal the external device 21 to further communicate with and deliver alerts through a network such as a Medtronic Network developed by Medtronic plc of Dublin, Ireland. network or some other network that links the patient 14 to the clinicians. The ICD 9 may transmit information to the network either spontaneously or in response to a query request from the user.

[0119] Power source 290 may be any type of device configured to hold an electrical charge to operate the circuitry of ICD 9. Power source 290 may be provided as a rechargeable or non-rechargeable battery. In other examples, power source 290 may incorporate an energy scavenging system that stores electrical energy from movement of ICD 9 within patient 14.

[0120] The various circuit systems of ICD 9 may include any one or more processors, controllers, DSPs, ASICs, FPGAs, or equivalent discrete or integrated circuit systems, including analog circuit systems, digital circuit systems, or logic circuit systems.

[0121] Figure 5 It shows Figures 1A to 1C 4. A functional block diagram of an example configuration of an external device 21 of FIG. 4. The external device 21 may include a processing circuit system 400, a memory 402, a communication circuit system 408, a user interface 406, a motion sensor 410 (which may include one or more accelerometers), and a power supply 404. The processing circuit system 400 controls the user interface 406 and the communication circuit system 408, and stores information and instructions to the memory 402 and retrieves information and instructions from the memory. The external device 21 may be configured to be used as a clinician programmer or a patient programmer. The processing circuit system 400 may include any combination of one or more processors, including one or more microprocessors, DSPs, ASICs, FPGAs, or other equivalent integrated or discrete logic circuit systems. Thus, the processing circuit system 400 may include any suitable structure, whether hardware, software, firmware, or any combination thereof, to perform the functions attributed to the processing circuit system 400 herein.

[0122] In some examples, motion sensor 410 may include a three-axis accelerometer, one or more single-axis accelerometers, etc. In examples where external device 21 may be a smartphone, a wearable device, etc., carried by patient 14 (e.g., in a pocket of patient 14), motion sensor 410 may be configured to generate one or more signals that may be indicative of patient 14's posture and / or activity.

[0123] A user, such as a clinician or patient 14, can interact with the external device 21 via a user interface 406. The user interface 406 can include a display, such as an LCD or LED display or other type of screen, to present information related to ATP therapy, including ATP therapy parameters stored in parameters 412 or in a memory of the IMD, or to display visual indications to the user or provide audio indications related to cardiac events. In addition, the user interface 406 can include an input mechanism for receiving input from the user. The input mechanism can include, for example, a button, a keypad (e.g., an alphanumeric keypad), a peripheral pointing device, or another input mechanism that allows the user to navigate the user interface presented by the processing circuit system 400 of the external device 21 and provide input.

[0124] If the external device 21 includes buttons and a keypad, these buttons may be dedicated to performing a certain function (i.e., a power button), or these buttons and keypad may be soft keys whose functions change depending on the portion of the user interface currently being viewed by the user. Alternatively, the screen of the external device 21 may be a touch screen that allows the user to provide input directly to the user interface shown on the display. The user may provide input to the display using a stylus or finger. In other examples, the user interface 406 also includes an audio circuit system for providing audible instructions or sounds (e.g., instructions regarding cardiac events) to the patient 14 and / or receiving voice commands from the patient 14—this may be useful if the patient 14 has limited motor function. The patient 14, a clinician, or another user may also interact with the external device 21 to manually select a therapy program, generate a new therapy plan, modify the therapy plan through individual or global adjustments, and transmit the new program to the ICD 9 and / or IPD 16.

[0125] In some examples, when external device 21 transmits a new program or command to IPD 16, the external device transmits the new program or command via ICD 9. Any data that may be retrieved or received by external device 21 from IPD 16 may also be transmitted via IPD 16. For example, when external device 21 attempts to transmit a new program to IPD 16, external device 21 may transmit the new program to ICD 9 and indicate that the new program is for IPD 16. ICD 9 may then send a first electrical signal to heart 26. IPD 16, which monitors the electrical activity of heart 26, may sense the first electrical signal and transmit the signal to ICD 9 via communication circuitry 268 ( Figure 3 ) and communication circuit system 284 ( Figure 4 ) initiates communication. ICD 9 can then transmit the new program to IPD 16 via the communication channel. In this way, IPD 16 does not have to use communication circuitry 268 to monitor the communication channel for a communication wake-up signal from external device 21.

[0126] In some examples, at least a portion of the control of therapy delivery by ICD 9 and / or IPD 16 may be implemented by processing circuitry 400 of external device 21. For example, in some examples, processing circuitry 400 may control the delivery of cardiac therapy, such as that performed by ICD 9 and / or IPD 16, by communicating with ICD 9 and / or IPD 16, and may receive data regarding sensed signals and control the electrical signal generation circuitry of either ICD 9 and / or IPD 16 by communicating with ICD 9 and / or IPD 16. In some examples, memory 402 may store ATP therapy parameters that may be used to control the electrical signal generation circuitry of ICD 9 and / or IPD 16, and / or may modify the ATP therapy parameters.

[0127] The memory 402 may include instructions for operating the user interface 406 and the communication circuit system 408, for managing the power supply 404, and for performing any functions attributed to the external device 21 (e.g., determining cardiac events, controlling the delivery of therapy, and / or generating instructions for output). The memory 402 may also store any therapy data, accelerometer data, or other sensory data retrieved from the PCD 110 during therapy. The clinician may use this therapy data to determine the progression of the patient's condition in order to predict future treatments. The memory 402 may include any volatile or non-volatile memory, such as RAM, ROM, FRAM, EEPROM, or flash memory. The memory 402 may also include a removable memory portion that can be used to provide memory updates or increases in memory capacity. The removable memory may also allow sensitive patient data to be removed before the external device 21 is used by a different patient.

[0128] Wireless telemetry in external device 21 can be achieved through RF communication or proximal sensing interaction between external device 21, ICD 9, and / or IPD 16. This wireless communication can be achieved using communication circuitry 408 with the aid of antenna 414, which can utilize proprietary protocols or industry-standard protocols, such as the Bluetooth profile set. Therefore, communication circuitry 408 can be similar to the communication circuitry included in ICD 9 and / or IPD 16. In alternative examples, external device 21 can be capable of infrared communication or direct communication via a wired connection. In this way, other external devices can be able to communicate with external device 21 without establishing a secure wireless connection.

[0129] The power supply 404 can deliver operating power to the components of the external device 21. The power supply 404 may include a battery and a power generation circuit for generating operating power. In some examples, the battery may be rechargeable to allow long-term operation. Recharging can be accomplished by electrically coupling the power supply 404 to a holder or plug connected to an AC outlet. In addition, recharging can be achieved through proximal inductive interaction between an external charger and an inductive charging coil within the external device 21. In other examples, conventional batteries (e.g., nickel-cadmium or lithium-ion batteries) can be used. In addition, the external device 21 can be directly coupled to an AC outlet for operation. The power supply 404 may include a circuit system for monitoring the remaining power within the battery. In this way, the user interface 406 can provide an indicator of the current battery charge or provide a low battery charge indicator when the battery needs to be replaced or recharged. In some cases, the power supply 404 may be able to estimate the remaining operating time using the current battery.

[0130] Figure 6is a flow chart illustrating an example communication technique for a first medical device according to one or more aspects of the present disclosure. Figure 4 Discussion in the context of ICD 9 Figure 6 , however these techniques may be performed by any device described herein that is capable of performing these techniques.

[0131] Processing circuitry 280 may control electrical signal generation circuitry 288 to deliver a first electrical signal to an anatomical structure of patient 14 (600). For example, processing circuitry 280 may control electrical signal generation circuitry 288 to deliver one or more pacing pulses to heart 26. In some examples, the one or more pacing pulses include at least one of a subthreshold energy pulse or a double pulse. Such a first electrical signal may be a signal used only when attempting to initiate communication with another medical device or between other medical devices. For example, the first electrical signal may represent non-channel-based signaling requesting a communication handshake with another medical device, such as IPD 16.

[0132] Processing circuitry 280 may control communication circuitry 284 to communicate with another medical device based on electrical signal generation circuitry 288 delivering the first electrical signal (602). For example, the other medical device (e.g., IPD 16) may send a communication, such as transmitting one or more pairing advertisements, such as Bluetooth pairing advertisements, or begin polling a communication channel in response to sensing the first electrical signal, such as when monitoring an anatomical structure, such as heart 26. Such an advertisement or polling may initiate communication between processing circuitry 280 and the other medical device.

[0133] In some examples, processing circuitry 280 can refrain from controlling communication circuitry to send a wake-up signal to the other medical device. For example, processing circuitry 280 can use the first electrical signal instead of sending a communication wake-up signal to the other medical device via the communication channel. In some examples, as part of communicating with the other medical device, communication circuitry 284 is configured to receive communications from the other medical device. In some examples, as part of communicating with the other medical device, communication circuitry 284 is configured to send communications to the other medical device.

[0134] In some examples, processing circuitry 280 may determine to control electrical signal generation circuitry 288 to deliver the first electrical signal based on at least one physiological parameter sensed (e.g., by sensing circuitry 286) or a communication from external device 21. In some examples, the at least one physiological parameter indicates a cardiac event, such as tachycardia.

[0135] In some examples, processing circuitry 280 controls communication circuitry 284 to send instructions to the other medical device. In some examples, the instructions include one or more of the following: starting delivery of therapy (e.g., ATP therapy, pacing pulses, shocks, etc.), stopping delivery of therapy, or configuring operation of the second IMD, such as reprogramming the other medical device.

[0136] Figure 7 is a flow chart illustrating an example communication technique for a second medical device according to one or more aspects of the present disclosure. Figure 3 Discussion in the context of IPD 16 Figure 7 , however these techniques may be performed by any device described herein that is capable of performing these techniques.

[0137] Processing circuitry 264 may receive a signal (700) from at least one of a sensor or sensing circuitry (e.g., electrode 52, electrode 60, and / or sensing circuitry 272). For example, sensing circuitry 272 and / or electrode 52 or electrode 60 may sense the signal. Processing circuitry 264 may determine that the signal indicates that a first electrical signal was delivered from another medical device (e.g., ICD 9) to an anatomical structure of patient 14 (702). For example, processing circuitry 264 may compare the sensed signal with parameters stored in parameters 276 indicating that the first electrical signal was delivered to an anatomical structure of patient 14 (e.g., heart 26) to determine that the signal indicates delivery of the first electrical signal.

[0138] The processing circuit system 264 may control the communication circuit system 268 to initiate communication with at least one of the other medical device or the third medical device based on receiving the signal indicating the delivery of the first electrical signal (704). For example, the processing circuit system 264 may control the communication circuit system 268 to send a communication to at least one of the other medical device or the third medical device, such as transmitting one or more pairing advertisements, such as Bluetooth pairing advertisements. Additionally or alternatively, the processing circuit system 264 may control the communication circuit system 268 to poll the communication channel.

[0139] In some examples, processing circuitry 264 may receive instructions from another device via communication circuitry 268. For example, communication circuitry 268 may receive instructions from ICD 9 and may send the instructions to processing circuitry 264. In some examples, the instructions include instructions for controlling the electrical signal generation circuitry to deliver therapy based on the received instructions. In some examples, the instructions include instructions for configuring the operation of IPD 16.

[0140] For example, a clinician may input a new program or different therapy parameters into the external device 21 ( Figure 5) in user interface 406 of the ICD 9. The external device may send a new program or different therapy parameters to the ICD 9 (which may monitor for the communication wake-up signal). The ICD 9 may send a first electrical signal to the heart 26, the IPD 16 may initiate communication with the ICD 9, and the ICD 9 may send instructions to the IPD 16.

[0141] Processing circuit system 264 can respond to the instruction. For example, processing circuit system 264 can control electrical signal generation circuit system 270 based on the received instruction to deliver therapy, or can configure the operation of the medical device. In some examples, the therapy includes anti-tachyarrhythmia pacing therapy.

[0142] In some examples, the first electrical signal includes one or more pacing pulses. In some examples, the one or more pacing pulses include at least one of a subthreshold energy pulse or a double pulse.

[0143] Figure 8 is a flow chart illustrating another example communication technique for a first medical device and a second medical device according to one or more aspects of the present disclosure. Figures 1A to 1C System 8 (including Figure 5 ICD 9 and Figures 2 to 3 Discussed in the context of IPD 16) Figure 8 , however these techniques may be performed by any device described herein that is capable of performing these techniques.

[0144] Processing circuitry 280 of ICD 9 may control electrical signal generation circuitry 288 to deliver a first electrical signal to the anatomy of patient 14 (800). For example, processing circuitry 280 may control electrical signal generation circuitry 288 to deliver an electrical signal to heart 26 of patient 14, and processing circuitry 280 may use only the electrical signal to initiate communication with another medical device (e.g., IPD 16) or other medical devices.

[0145] Processing circuitry 264 of IPD 16 may receive a signal (802) from at least one of a sensor or sensing circuitry (e.g., electrodes 52 and / or 60 and / or sensing circuitry) indicating that a first electrical signal is being delivered by a first medical device (e.g., ICD 9) to an anatomical structure (e.g., heart 26) of patient 14. For example, sensing circuitry 272 and / or electrodes 52 and / or 60 may monitor electrical signals of heart 26, may sense the first electrical signal, and may send the first electrical signal to processing circuitry 264.

[0146] The processing circuitry 264 may control the communication circuitry 268 to initiate communication with at least one of the first medical device (e.g., ICD 9) or the third medical device based on receiving the signal indicating delivery of the first electrical signal (804). For example, the IPD 16 may send a communication to the ICD 9 and / or the third medical device, such as transmitting one or more pairing advertisements, such as Bluetooth pairing advertisements, or the IPD 16 may begin polling a communication channel in response to receiving the signal indicating delivery of the first electrical signal. For example, the IPD 16 may be configured to recognize the first electrical signal as a trigger for the IPD 16 to initiate communication with the ICD 9 and / or the third medical device.

[0147] In some examples, controlling communication circuitry 268 to initiate communication with at least one of the first medical device (ICD 9) or the third medical device includes sending a communication to the first medical device. In some examples, processing circuitry 280 can receive a communication from the second medical device (IPD 16) via communication circuitry 284 based on electrical signal generation circuitry 288 delivering the first electrical signal. In some examples, processing circuitry 280 can control communication circuitry 284 to send an instruction to the second medical device based on receiving the communication from the second medical device. In some examples, processing circuitry 264 can receive an instruction from the first medical device (ICD 9) via communication circuitry 268, and processing circuitry 264 can respond to the instruction.

[0148] Any suitable modifications may be made to the techniques described herein, and any suitable devices, processing circuitry, electrical signal generating circuitry, and / or electrodes may be used to perform the steps of the methods described herein. The steps of these methods may be performed by any suitable number of devices. For example, the processing circuitry of one device may perform some of the steps, while the electrical signal generating circuitry and / or sensing circuitry of another device may perform other steps of the method, and the communication circuitry may enable the processing circuitry to communicate with the other devices to receive information. This coordination may be performed in any suitable manner, depending on the particular needs.

[0149] The present disclosure contemplates a computer-readable storage medium comprising instructions that cause a processor to perform any of the functions and techniques described herein. The computer-readable storage medium can take the form of any volatile, non-volatile, magnetic, optical, or electrical medium, such as RAM, ROM, FRAM, NVRAM, EEPROM, or flash memory. The computer-readable storage medium can be referred to as non-transitory. Programmers such as patient programmers or clinician programmers, or other computing devices can also contain more portable removable memory types to enable easy data transfer or offline data analysis.

[0150] The technology described in this disclosure, including technology attributed to ICD 9, IPD 16, PCD 110, ICM 300, external device 21, and various component parts, may be implemented at least in part in hardware, software, firmware, or any combination thereof. For example, various aspects of the technology may be implemented within one or more processors including one or more microprocessors, DSPs, ASICs, FPGAs, or any other equivalent integrated or discrete logic circuitry embodied in a programmer (such as a physician or patient programmer), a stimulator, a remote server, or other device, and any combination of such components. The term "processor" or "processing circuitry" may generally refer to any of the foregoing logic circuitry, alone or in combination with other logic circuitry, or any other equivalent circuitry.

[0151] Such hardware, software, and firmware may be implemented within the same device or within separate devices to support the various operations and functions described in this disclosure. For example, any of the techniques or processes described herein may be performed within a single device or at least partially distributed across two or more devices, such as the ICD 9, IPD 16, PCD 110, ICM 300, and / or external device 21. Furthermore, any of the described units, circuit systems, or components may be implemented together or separately as discrete but interoperable logic devices. The descriptions of different features of circuit systems are intended to highlight different functional aspects and do not necessarily imply that such circuit systems must be implemented by separate hardware or software components. Rather, the functions associated with one or more circuit systems may be performed by separate hardware or software components, or integrated within common or separate hardware or software components.

[0152] The techniques described in this disclosure may also be embodied or encoded in an article of manufacture comprising a non-transitory computer-readable storage medium encoded with instructions. The instructions embedded or encoded in an article of manufacture comprising an encoded non-transitory computer-readable storage medium may cause one or more programmable processors or other processors to implement one or more techniques described herein, such as when the instructions included or encoded in the non-transitory computer-readable storage medium are executed by one or more processors. Example non-transitory computer-readable storage media may include random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory, hard disk, compact disk ROM (CD-ROM), floppy disk, cassette tape, magnetic media, optical media, or any other computer-readable storage device or tangible computer-readable medium.

[0153] As used herein, the term "circuitry" refers to ASICs, electronic circuits, processors (shared, dedicated, or groups) and memory, combinational logic, and / or other suitable components that execute one or more software or firmware programs to provide the described functionality.

[0154] In some examples, computer-readable storage media include non-transitory media. The term "non-transitory" may indicate that the storage medium is not embodied in a carrier wave or propagating signal. In some examples, non-transitory storage media may store data that may change over time (e.g., in RAM or cache).

[0155] Various embodiments have been described for delivering cardiac stimulation therapy and coordinating the operation of various devices within a patient. Any combination of the described operations or functions is contemplated. These and other embodiments are within the scope of the following claims.

[0156] The following examples are a non-limiting list of clauses in accordance with one or more techniques of this disclosure.

[0157] Embodiment 1. A medical device, comprising: a memory configured to store parameters of a first electrical signal for a patient; a communication circuit system;

[0158] an electrical signal generating circuit system; and a processing circuit system communicatively coupled to the memory, the communication circuit system, and the electrical signal generating circuit system, the processing circuit system being configured to: control the electrical signal generating circuit system to deliver the first electrical signal to the patient's anatomical structure; and control the communication circuit system to communicate with another medical device based on the electrical signal generating circuit system delivering the first electrical signal.

[0159] Embodiment 2. The medical device of embodiment 1, wherein the processing circuitry is further configured to refrain from controlling the communication circuitry to send a wake-up signal to the other medical device.

[0160] Example 3. The medical device of Example 1 or Example 2, wherein as part of communicating with the other medical device, the communication circuitry is configured to receive communications from the other medical device.

[0161] Embodiment 4. The medical device of any one of Embodiments 1 to 3, wherein as part of communicating with the other medical device, the communication circuitry is configured to send communications to the other medical device.

[0162] Example 5. A medical device according to any one of Examples 1 to 4, further comprising at least one of a sensor or a sensing circuit system configured to sense a physiological parameter of the patient, wherein the processing circuit system is further configured to determine control of the electrical signal generating circuit system to deliver the first electrical signal based on at least one sensed physiological parameter or communication from an external device.

[0163] Example 6. The medical device of Example 5, wherein the at least one sensed physiological parameter is indicative of a cardiac event.

[0164] Example 7. The medical device of Example 6, wherein the cardiac event comprises tachycardia.

[0165] Embodiment 8 The medical device of any one of Embodiments 1 to 7, wherein the processing circuit system is further configured to control the communication circuit system to send instructions to the other medical device.

[0166] Example 9. The medical device of Example 8, wherein the instructions include one or more of the following: instructions for initiating delivery of pacing pulses to the patient's heart;

[0167] Instructions for ceasing delivery of pacing pulses to the heart of the patient; or instructions including configuration information for configuring the operation of the other medical device.

[0168] Example 10. The medical device of any one of Examples 1 to 9, wherein the first electrical signal comprises one or more pacing pulses.

[0169] Example 11. The medical device of Example 10, wherein the one or more pacing pulses include at least one of a subthreshold energy pulse or a double pulse.

[0170] Embodiment 12. The medical device of any one of Embodiments 1 to 11, wherein the medical device comprises an external cardiovascular defibrillator.

[0171] Embodiment 13. A medical device comprising: a memory configured to store parameters indicative of delivery of a first electrical signal to an anatomical structure of a patient;

[0172] communications circuitry; at least one of a sensor or sensing circuitry;

[0173] and processing circuitry communicatively coupled to the memory, the communication circuitry, and the at least one of the sensor or the sensing circuitry, the processing circuitry configured to: receive a signal from the at least one of the sensor or the sensing circuitry; determine that the signal indicates delivery of the first electrical signal to the anatomical structure of the patient by another medical device;

[0174] and controlling the communication circuitry to initiate communication with at least one of the other medical device or a third medical device based on receiving the signal indicative of the delivery of the first electrical signal.

[0175] Example 14. The medical device of Example 13, wherein as part of controlling the communication circuitry to initiate communication with the other medical device, the processing circuitry is configured to control the communication circuitry to send communications to at least one of the other medical device or the third medical device.

[0176] Example 15. The medical device of Example 13 or Example 14, wherein as part of controlling the communication circuitry to initiate communication with the other medical device, the processing circuitry is configured to control the communication circuitry to poll a communication channel.

[0177] Embodiment 16. The medical device of any one of Embodiments 13 to 15, wherein the processing circuitry is further configured to: receive an instruction from the other medical device via the communication circuitry; and respond to the instruction.

[0178] Example 17. The medical device of Example 16, further comprising an electrical signal generating circuit system, and wherein as part of responding to the instruction, the processing circuit system is configured to control the electrical signal generating circuit system to deliver therapy based on the received instruction.

[0179] Example 18. The medical device of Example 17, wherein the therapy comprises anti-tachyarrhythmia pacing therapy.

[0180] Embodiment 19. The medical device of any one of Embodiments 16 to 18, wherein as part of responding to the instruction, the processing circuitry is configured to configure the operation of the medical device based on the received instruction.

[0181] Example 20. The medical device of any one of Examples 13 to 19, wherein the medical device comprises a pacemaker.

[0182] Example 21. The medical device of any one of Examples 13 to 20, wherein the first electrical signal comprises one or more pacing pulses.

[0183] Example 22. The medical device of Example 21, wherein the one or more pacing pulses comprise at least one of a subthreshold energy pulse or a double pulse.

[0184] Embodiment 23. A method comprising: controlling an electrical signal generating circuit system to deliver a first electrical signal to an anatomical structure of a patient through a processing circuit system; and controlling a communication circuit system to communicate with another medical device through the processing circuit system and based on the electrical signal generating circuit system delivering the first electrical signal.

[0185] Embodiment 24. The method according to embodiment 23, further comprising refraining, by the processing circuit system, from controlling the communication circuit system to send a wake-up signal to the other medical device.

[0186] Example 25. The method of Example 23 or Example 24, wherein communicating with the other medical device comprises receiving communications from the other medical device.

[0187] Embodiment 26. The method of any one of Embodiments 23 to 25, wherein communicating with the other medical device comprises sending a communication to the other medical device.

[0188] Embodiment 27. The method according to any one of embodiments 23 to 26, further comprising determining to control the electrical signal generating circuit system to deliver the first electrical signal based on at least one sensed physiological parameter or communication from an external device.

[0189] Example 28. The method of Example 27, wherein the one or more sensor signals are indicative of a cardiac event.

[0190] Example 29. The method of Example 28, wherein the cardiac event comprises tachycardia.

[0191] Embodiment 30. The method according to any one of embodiments 23 to 29, further comprising controlling the communication circuit system through the processing circuit system to send instructions to the other medical device.

[0192] Example 31. The method of any one of Examples 23 to 30, wherein the instructions include one or more of: instructions for delivering pacing pulses to the patient's heart; instructions for ceasing delivery of pacing pulses to the patient's heart;

[0193] Or configuration information for configuring the operation of the other medical device.

[0194] Example 32. A method according to any one of Examples 23 to 31, wherein the first electrical signal includes one or more pacing pulses.

[0195] Example 33. The method of Example 32, wherein the one or more pacing pulses include at least one of a subthreshold energy pulse or a double pulse.

[0196] Example 34. A method comprising: receiving a signal from a sensor or sensing circuit system of a medical device through a processing circuit system of the medical device; determining that the signal indicates delivery of a first electrical signal to an anatomical structure of a patient by another medical device; and controlling a communication circuit system to initiate communication with the other medical device or at least one of a third medical device through the processing circuit system and based on receiving the signal indicating the delivery of the first electrical signal.

[0197] Embodiment 35. The method of Embodiment 34, wherein controlling the communication circuitry to initiate communication with the other medical device comprises controlling the communication circuitry to send a communication to at least one of the other medical device or the third medical device.

[0198] Embodiment 36 The method of any one of Embodiment 34 or Embodiment 35, wherein controlling the communication circuitry to initiate communication with the other medical device comprises controlling the communication circuitry to poll a communication channel.

[0199] Embodiment 37. The method according to any one of embodiments 34 to 36, further comprising:

[0200] receiving, by the processing circuitry and via the communication circuitry, an instruction from the other medical device; and responding, by the processing circuitry, to the instruction. Embodiment 38. The method of Embodiment 37, wherein responding to the instruction comprises controlling the electrical signal generating circuitry to deliver therapy based on the received instruction.

[0201] Example 39. The method of Example 38, wherein the therapy comprises anti-tachyarrhythmia pacing therapy.

[0202] Embodiment 40. The method of any one of Embodiments 34 to 39, wherein responding to the instruction comprises instructions for configuring the operation of the medical device.

[0203] Example 41. A method according to any one of Examples 34 to 40, wherein the first electrical signal includes one or more pacing pulses.

[0204] Example 42. The method of Example 41, wherein the one or more pacing pulses include at least one of a subthreshold energy pulse or a double pulse.

[0205] Embodiment 43. A method comprising: controlling, by first processing circuitry of a first medical device, electrical signal generation circuitry to deliver a first electrical signal to an anatomical structure of a patient; receiving, by second processing circuitry of a second medical device and from at least one of a sensor or sensing circuitry, a signal indicating delivery of the first electrical signal from the first medical device to the anatomical structure of the patient;

[0206] Second communication circuitry is controlled, by the second processing circuitry and based on receiving the signal indicative of the delivery of the first electrical signal, to initiate communication with at least one of the first medical device or a third medical device.

[0207] Example 44. A method according to Example 43, wherein controlling the second communication circuit system to initiate communication with at least one of the first medical device or the third medical device includes sending communication to the first medical device, the method further comprising: receiving the communication from the second medical device via the first communication circuit system through the first processing circuit system and based on the electrical signal generating circuit system that delivers the first electrical signal; controlling the first communication circuit system to send an instruction to the second medical device through the first processing circuit system and based on receiving the communication from the second medical device; receiving the instruction from the first medical device through the second processing circuit system and via the second communication circuit system; and responding to the instruction through the second processing circuit system.

[0208] Embodiment 45. A non-transitory computer-readable storage medium having stored thereon instructions that, when executed, cause processing circuitry to: control electrical signal generation circuitry to deliver a first electrical signal;

[0209] and communicating with another medical device via the communication circuitry based on the electrical signal generation circuitry delivering the first electrical signal.

[0210] Example 46. A non-transitory computer-readable storage medium having instructions stored thereon that, when executed, cause a processing circuit system to: receive a signal from at least one of a sensor or a sensing circuit system; determine that the signal indicates that a first electrical signal is delivered from another medical device to an anatomical structure of a patient; and based on receiving the signal indicating the delivery of the first electrical signal, control the communication circuit system to initiate communication with the other medical device.

Claims

1. A medical device, comprising: a memory configured to store parameters of a first electrical signal for a patient; Communication circuit systems; an electrical signal generating circuit system; and processing circuitry communicatively coupled to the memory, the communications circuitry, and the electrical signal generation circuitry, the processing circuitry configured to: controlling the electrical signal generating circuitry to deliver the first electrical signal to an anatomical structure of the patient; and Based on the electrical signal generation circuitry delivering the first electrical signal, the communication circuitry is controlled to communicate with another medical device. 2 . The medical device of claim 1 , wherein the processing circuit system is further configured to refrain from controlling the communication circuit system to send a wake-up signal to the other medical device.

3. The medical device of claim 1 or claim 2, wherein as part of communicating with the other medical device, the communication circuit system is configured to one or more of: receive communications from the other medical device or send communications to the other medical device.

4. A medical device according to any one of claims 1 to 3, wherein the medical device also includes at least one of a sensor or a sensing circuit system configured to sense a physiological parameter of the patient, wherein the processing circuit system is also configured to determine to control the electrical signal generating circuit system to deliver the first electrical signal based on at least one sensed physiological parameter or communication from an external device. The medical device of claim 4 , wherein the at least one sensed physiological parameter is indicative of a cardiac event. The medical device of claim 5 , wherein the cardiac event comprises tachycardia.

7. The medical device according to any one of claims 1 to 6, wherein the processing circuit system is further configured to control the communication circuit system to send instructions to the other medical device.

8. The medical device of claim 7, wherein the instructions include one or more of the following: a command for initiating delivery of pacing pulses to the patient's heart; instructions for ceasing delivery of pacing pulses to the heart of the patient; or Instructions include configuration information for configuring the operation of the other medical device.

9. The medical device of any one of claims 1 to 8, wherein the first electrical signal comprises one or more pacing pulses.

10. The medical device of claim 9, wherein the one or more pacing pulses comprise at least one of a subthreshold energy pulse or a double pulse.

11. The medical device according to any one of claims 1 to 10, wherein the medical device comprises an external cardiovascular defibrillator.

12. A medical device, comprising: a memory configured to store parameters indicative of delivery of a first electrical signal to an anatomical structure of a patient; Communication circuit systems; at least one of a sensor or sensing circuitry; and a processing circuit system communicatively coupled to the memory, the communication circuit system, and the at least one of the sensor or the sensing circuit system, the processing circuit system being configured to: receiving a signal from said at least one of said sensor or said sensing circuitry; determining that the signal indicates delivery of the first electrical signal to the anatomical structure of the patient by another medical device; and based on receiving said signal indicative of said delivery of said first electrical signal, The communication circuitry is controlled to initiate communication with at least one of the other medical device or a third medical device.

13. The medical device of claim 12, wherein as part of controlling the communication circuit system to initiate the communication with the other medical device, the processing circuit system is configured to control the communication circuit system to send one or more of the communications to the other medical device or at least one of the third medical device, or to control the communication circuit system to poll a communication channel.

14. The medical device of any one of claims 12 to 13, wherein the processing circuit system is further configured to: receiving instructions from the other medical device via the communication circuitry; and Respond to the instruction.

15. The medical device of claim 15, further comprising electrical signal generating circuitry, and wherein as part of responding to the instructions, the processing circuitry is configured to control the electrical signal generating circuitry to deliver therapy based on the received instructions.

16. The medical device of claim 16, wherein the therapy comprises anti-tachyarrhythmia pacing therapy.

17. The medical device of any one of claims 15 to 17, wherein as part of responding to the instructions, the processing circuitry is configured to configure operation of the medical device based on the received instructions.

18. The medical device of any one of claims 12 to 18, wherein the medical device comprises a pacemaker.

19. The medical device of any one of claims 12 to 19, wherein the first electrical signal comprises one or more pacing pulses.

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