CN116920278A

CN116920278A - Implantable cardiac pacemaker, program control device and cardiac pacing system

Info

Publication number: CN116920278A
Application number: CN202210349277.XA
Authority: CN
Inventors: 张建锋
Original assignee: Microport Sorin CRM Shanghai Co Ltd
Current assignee: Microport Sorin CRM Shanghai Co Ltd
Priority date: 2022-04-01
Filing date: 2022-04-01
Publication date: 2023-10-24
Also published as: WO2023185606A1

Abstract

The invention relates to an implantable cardiac pacemaker, a program control device and a cardiac pacing system. The implantable cardiac pacemaker utilizes the variable acoustic impedance module to sense the ultrasonic signal on one hand, can acquire data from the outside by utilizing the ultrasonic signal, and on the other hand, generates a corresponding ultrasonic reflection signal by changing the acoustic impedance of the variable acoustic impedance module, and can send data to the outside by utilizing the ultrasonic reflection signal. The programming device and cardiac pacing system have similar advantages.

Description

Implantable cardiac pacemaker, program control device and cardiac pacing system

Technical Field

The invention relates to the field of medicine, in particular to an implantable cardiac pacemaker, a program control device and a cardiac pacing system.

Background

The implanted cardiac pacemaker is a great contribution to human beings from modern biomedical engineering, so that serious arrhythmia patients with ineffective traditional drug treatment can be treated by the implanted cardiac pacemaker, and the cardiac pacemaker is also applied to tachyarrhythmia and non-electrocardio diseases, such as preventing paroxysmal atrial tachyarrhythmia, carotid sinus syncope, double-chamber synchronous treatment drug-refractory congestive heart failure and the like, while the pacemaker is applied to successfully treat bradycardia and save thousands of patient lives, so that the death rate of cardiovascular diseases is greatly reduced.

With the development of technology and application, modern implantable cardiac pacemakers need to have the function of duplex communication with the outside, for example, external equipment is used for performing program control and wireless telemetry on the implanted cardiac pacemakers. Meanwhile, cardiac pacemakers are improved in light weight and miniaturization, for example, an implantable leadless cardiac pacemaker which has been developed at present has the advantages of reducing complications, being small in wound, convenient to implant, compatible with MRI and the like, and is the development direction of future pacing technology.

However, in the case of an implantable leadless cardiac pacemaker, due to the limitations of small volume and small battery capacity, wireless communication methods such as a magnetic induction coil and Radio Frequency (RF) employed in the conventional cardiac pacemaker cannot be fully used. The HBC (body communication) is disclosed as an alternative communication mode of an implantable leadless cardiac pacemaker, which uses human tissue as a medium for current conduction, and performs program control and telemetry by emitting discharge pulses or collecting electric pulse signals at the electrode end of the pacemaker and collecting or emitting electric pulse signals at the surface of the human body. However, when HBC communication is adopted, in order to avoid affecting the normal rhythm function of the heart and to avoid affecting the normal pacing function, communication needs to be completed in a refractory period, so that real-time transmission of some real-time event signals (such as endocardial event signals) cannot be performed. In addition, in order to avoid interference in the transmission process, HBCs typically use frequency shift keying and other modes to perform modulation and demodulation, and the circuits are relatively complex, and power consumption is also high, which still has problems in application.

Disclosure of Invention

In order to improve the real-time performance of the communication between the implantable cardiac pacemaker and the outside, the invention provides the implantable cardiac pacemaker, the program control device and the cardiac pacing system.

In one aspect, the invention provides an implantable cardiac pacemaker, comprising a variable acoustic impedance module and a signal processing module, wherein the variable acoustic impedance module is used for sensing an ultrasonic signal, converting the ultrasonic signal into a corresponding electric signal and then transmitting the corresponding electric signal to the signal processing module, and the acoustic impedance of the variable acoustic impedance module can be changed under the control of the signal processing module and generating a corresponding ultrasonic reflection signal; the ultrasound signal and the ultrasound reflected signal are used by the implantable cardiac pacemaker to communicate with the outside.

Optionally, the variable acoustic impedance module includes a variable acoustic impedance film electrically connected to the signal processing module; the acoustic impedance of the variable acoustic impedance film is different according to different signals of the signal processing module, and the acoustic impedance of the variable acoustic impedance film generates corresponding ultrasonic reflection signals according to the signals of the signal processing module.

Optionally, the variable acoustic impedance module further includes a piezoelectric film electrically connected to the signal processing module, where the piezoelectric film is configured to sense the ultrasonic signal, convert the ultrasonic signal into a corresponding electrical signal, and send the electrical signal to the signal processing module.

Optionally, the implantable cardiac pacemaker further comprises a housing, the housing is sleeved outside the variable acoustic impedance module and the signal processing module, the variable acoustic impedance module further comprises a back lining, the back lining is arranged on the inner surface of the housing, and the piezoelectric film and the variable acoustic impedance film are distributed on the back lining in a partitioning mode.

Optionally, the variable acoustic impedance module further includes a first acoustic absorption film and a second acoustic absorption film, the first acoustic absorption film is located between the piezoelectric film and the variable acoustic impedance film, and the second acoustic absorption film is located at a side of the variable acoustic impedance film away from the annular piezoelectric film.

Optionally, the piezoelectric film, the variable acoustic impedance film, the first acoustic absorption film and the second acoustic absorption film are all in annular structures, and axes of the piezoelectric film, the variable acoustic impedance film, the first acoustic absorption film and the second acoustic absorption film are parallel.

Optionally, the width of the first sound absorbing film is different from the width of the second sound absorbing film, and each is different from the width of the variable acoustic impedance film.

Optionally, the signal processing module changes the acoustic impedance of the variable acoustic impedance module by powering on or off the variable acoustic impedance film.

Optionally, the signal processing module includes a processor, an ADC unit, and a DAC unit; the ADC unit is used for converting the electric signal sent by the variable acoustic impedance module into a digital signal and sending the digital signal to the processor; the DAC unit is used for converting the signal which is sent by the processor and used for changing the acoustic impedance into an analog signal and sending the analog signal to the variable acoustic impedance module, and the variable acoustic impedance module adjusts the acoustic impedance according to the analog signal sent by the DAC unit.

Optionally, the implantable cardiac pacemaker is a leadless pacemaker.

In one aspect, the invention provides a program control device, which comprises a program control instrument host and an ultrasonic program control head; the ultrasonic program control head is used for sending ultrasonic signals and sensing ultrasonic reflection signals; the main machine of the program control instrument transmits data to the implantable cardiac pacemaker through an ultrasonic signal sent by the ultrasonic program control head, obtains the acoustic impedance state of the implantable cardiac pacemaker through an ultrasonic reflection signal perceived by the ultrasonic program control head, and obtains the data of the implantable cardiac pacemaker according to the change of the acoustic impedance state.

In one aspect, the present invention provides a cardiac pacing system comprising an implantable cardiac pacemaker as described above and a programming device.

The implantable cardiac pacemaker provided by the invention comprises a variable acoustic impedance module and a signal processing module, wherein the variable acoustic impedance module is used for sensing ultrasonic signals, converting the ultrasonic signals into corresponding electric signals and then sending the corresponding electric signals to the signal processing module, and the acoustic impedance of the variable acoustic impedance module can be changed under the control of the signal processing module to generate corresponding ultrasonic reflection signals; the ultrasound signal and the ultrasound reflected signal are used by the implantable cardiac pacemaker to communicate with the outside. The implantable cardiac pacemaker senses the ultrasonic signal by utilizing the variable acoustic impedance module, can acquire data from the outside by utilizing the ultrasonic signal, generates a corresponding ultrasonic reflection signal by changing the acoustic impedance of the variable acoustic impedance module, and can transmit data to the outside by utilizing the ultrasonic reflection signal. And moreover, the implantable cardiac pacemaker is communicated based on the mode that the acoustic impedance of the implanted end is changed under single-source ultrasound, the requirements on the circuit structure and the battery capacity of the implanted end are low in the communication process, and the implantable cardiac pacemaker is convenient to miniaturize, and a leadless pacemaker can be adopted for example.

In the program control device provided by the invention, the ultrasonic program control head can send ultrasonic signals and perceived ultrasonic reflection signals, the main machine of the program control instrument transmits data to the implantable cardiac pacemaker through the ultrasonic signals, the acoustic impedance state of the implantable cardiac pacemaker is obtained through the ultrasonic reflection signals perceived by the ultrasonic program control head, the data of the implantable cardiac pacemaker is obtained according to the change of the acoustic impedance state, and the ultrasonic signals and the ultrasonic reflection signals are used for communication instead of human tissues as current conduction mediums, so that the influence of a cardiac cycle is avoided, communication can be initiated by external ultrasonic sending and receiving equipment at any time according to requirements, and the real-time performance is high.

The cardiac pacing system provided by the invention comprises the implantable cardiac pacemaker and the program control device, can realize real-time communication with external equipment, has lower requirements on the circuit structure and the battery capacity of an implantation end in the communication process, and is convenient for miniaturization of the implantable cardiac pacemaker.

Drawings

Fig. 1 is a schematic diagram of a cardiac pacing system according to an embodiment of the present invention.

Fig. 2 is a schematic diagram of an implantable cardiac pacemaker according to one embodiment of the present invention.

Fig. 3 is a schematic view of a localized area in the implantable cardiac pacemaker shown in fig. 2.

Fig. 4 is a flow chart of communication between an implantable cardiac pacemaker and a programming device according to one embodiment of the present invention.

Fig. 5 is a schematic diagram of a communication frame for data transmission between implantable cardiac pacemaker 100 and programming device 200 according to one embodiment of the present invention.

Reference numerals illustrate:

100-an implantable cardiac pacemaker; 101-a housing; 110-a variable acoustic impedance module; 111-a variable acoustic impedance film; 112-a piezoelectric film; 113-backing; 114-a first sound absorbing film; 115-a second sound absorbing film; 120-a signal processing module; 121-a processor; a 122-ADC unit; a 123-DAC unit; 200-program control device; 210-a program control instrument host; 220-ultrasonic programming head.

Detailed Description

The implantable cardiac pacemaker, the programming device and the cardiac pacing system according to the present invention will be described in further detail with reference to the accompanying drawings and the specific embodiments. The advantages and features of the present invention will become more apparent from the following description. It should be understood that the drawings in the specification are in a very simplified form and are all to a non-precise scale, simply to facilitate a clear and thorough description of the embodiments of the invention.

Fig. 1 is a schematic diagram of a cardiac pacing system according to an embodiment of the present invention. Referring to fig. 1, an embodiment of the present invention relates to an implantable cardiac pacemaker 100, a programmable device 200 and a cardiac pacing system, wherein the cardiac pacing system comprises the implantable cardiac pacemaker 100 and the programmable device 200, the implantable cardiac pacemaker 100 is implanted in a body when the cardiac pacing system is in operation, the programmable device 200 is located outside the body, and the implantable cardiac pacemaker 100 and the programmable device 200 can communicate with each other by adopting ultrasonic signals and ultrasonic reflection signals so as to meet the requirements of program control and telemetry, and the cardiac pacing system can be applied to occasions that a doctor or a patient modifies parameters of implantable medical equipment through external program setting, or reads data stored in operation of the implantable medical equipment and the like. The specific description is as follows.

The implantable cardiac pacemaker 100 of the embodiment of the present invention includes a variable acoustic impedance module 110 and a signal processing module (not shown in fig. 1) disposed within a housing; the variable acoustic impedance module 110 is configured to sense an ultrasonic signal, convert the ultrasonic signal into a corresponding electrical signal, and send the electrical signal to the signal processing module; the acoustic impedance of the variable acoustic impedance module 110 is changeable under the control of the signal processing module, and generates a corresponding ultrasonic reflection signal; the ultrasound signal and the ultrasound reflected signal are used for the implantable cardiac pacemaker 100 to communicate with the outside. The implantable cardiac pacemaker 100 senses an ultrasonic signal using the variable acoustic impedance module 110 on the one hand, with which data can be acquired from the outside, and generates a corresponding ultrasonic reflection signal by changing the acoustic impedance of the variable acoustic impedance module 110, which thus changes with the change of the acoustic impedance of the variable acoustic impedance module 110, with which data can be transmitted to the outside.

Fig. 2 is a schematic diagram of an implantable cardiac pacemaker according to one embodiment of the present invention. Fig. 3 is a schematic view of a localized area in the implantable cardiac pacemaker shown in fig. 2. Referring to fig. 2 and 3, in an embodiment, the variable acoustic impedance module 110 in the implantable cardiac pacemaker 100 may include a variable acoustic impedance film 111, the variable acoustic impedance film 111 being electrically connected with a signal processing module in the variable acoustic impedance module 110, the acoustic impedance of the variable acoustic impedance film 111 being different according to different signals of the signal processing module, the acoustic impedance of the variable acoustic impedance film 111 generating a corresponding ultrasonic reflection signal according to the signal of the signal processing module, so that the implantable cardiac pacemaker 100 transmits data to the outside. In this embodiment, the variable acoustic impedance module 110 further includes a piezoelectric film 112 electrically connected to the signal processing module, where the piezoelectric film 112 is configured to sense an ultrasonic signal, convert the sensed ultrasonic signal into a corresponding electrical signal, and send the electrical signal to the signal processing module.

The variable acoustic impedance film 111 and the piezoelectric film 112 in the variable acoustic impedance module 110 may include a piezoelectric layer, a first electrode disposed on one surface of the piezoelectric layer, and a second electrode disposed on the other surface of the piezoelectric layer, wherein the piezoelectric layer may be made of polyvinylidene fluoride (PVDF), aluminum nitride (AlN), zinc oxide (ZnO), lead zirconate titanate (PZT), lithium niobium oxide (LiNbO) ₃ ) Tantalum lithium oxide (LiTaO) ₃ ) Or one or more of the other piezoelectric materials.

In the embodiment shown in fig. 2 and 3, the variable acoustic impedance module 110 generates an ultrasonic reflection signal using the variable acoustic impedance film 111 and additionally senses an ultrasonic signal using the piezoelectric film 112, so that signal processing processes of the variable acoustic impedance film 11 and the piezoelectric film 112 do not interfere with each other, and the signal processing module can transmit another electric signal to the variable acoustic impedance film 111 while receiving the electric signal generated by the piezoelectric film 112 based on the sensed ultrasonic signal, so that full duplex communication can be realized. The present invention is not limited thereto, and in another embodiment, the variable acoustic impedance module 110 may not be provided with the piezoelectric film 112, but the variable acoustic impedance film 111 for generating the ultrasonic reflection signal senses the ultrasonic signal and converts the ultrasonic signal into a corresponding electrical signal and transmits the electrical signal to the signal processing module, and the process of processing the ultrasonic signal by the variable acoustic impedance film 111 and the process of generating the ultrasonic reflection signal may be performed in a time-sharing manner.

Referring to fig. 1 to 3, the implantable cardiac pacemaker 100 may further include a housing 101, the housing 101 being sleeved outside the variable acoustic impedance module 110 and the signal processing module. The variable acoustic impedance module 110 may further include a backing 113, the backing 113 being disposed on an inner surface of the housing 101, the piezoelectric film 112 and the variable acoustic impedance film 111 being arranged on the backing 113 in a partitioned manner. An ultrasonic signal from the outside reaches the backing 113 and is perceived by the piezoelectric film 201.

The variable acoustic impedance module 110 may further include a first sound absorbing film 114 and a second sound absorbing film 115, the first sound absorbing film 114 and the second sound absorbing film 115 being located, for example, on an inner surface of the backing 113. The first sound absorbing film 114 is located between the piezoelectric film 112 and the variable acoustic impedance film 111 to isolate the same, and the second sound absorbing film 115 is located at a side of the variable acoustic impedance film 111 remote from the piezoelectric film 112. The first sound absorbing film 114 and the second sound absorbing film 115 are utilized to facilitate determining the emission position of the ultrasonic reflection signal, and then the state of the variable acoustic impedance film 111 is found and detected based on the emission position. The width directions of the first sound absorbing film 114 and the second sound absorbing film 115 are along the arrangement directions of the piezoelectric film 112 and the variable acoustic impedance film 111. In order to improve the accuracy of positioning, the width of the first sound absorbing film 114 may be set to be different from the width of the second sound absorbing film 115, and both may be different from the width of the variable acoustic impedance film 111. As shown in fig. 3, in one embodiment, the width of the second sound absorbing film 115 is greater than the width of the variable acoustic impedance film 111 and the width of the first sound absorbing film 114 is less than the width of the variable acoustic impedance film 111, but not limited thereto, and in another embodiment, the width of the second sound absorbing film 115 is less than the width of the variable acoustic impedance film 111 and the width of the first sound absorbing film 114 is greater than the width of the variable acoustic impedance film 111.

Considering that the penetration, reflection and refraction of the ultrasonic wave in the body are complex, and the surface of the implantable cardiac pacemaker 100 facing the chest cavity of the human body is not easy to control when the implantable cardiac pacemaker 100 is implanted in the human body, for the convenience of ultrasonic positioning, the housing 101 of the implantable cardiac pacemaker 100 may be selected to have a cylindrical structure (for example, a cylindrical structure, and an outer side surface of the cylindrical structure is a cylindrical surface) as shown in fig. 2, and the battery of the implantable cardiac pacemaker 100 may be disposed in the cylindrical structure. The variable acoustic impedance module 110 may be disposed within the cylinder structure in a hollow annular structure, the hollow being capable of being fed through an electrode. By way of example, the piezoelectric film 112, the variable acoustic impedance film 111, the first acoustic absorption film 114 and the second acoustic absorption film 115 described above may be connected end to end within the housing 101, i.e. all provided in a ring-like structure, with the axes of the piezoelectric film, the variable acoustic impedance film, the first acoustic absorption film and the second acoustic absorption film being, for example, parallel. The axis of the ring structure may be arranged parallel to the axis of the housing 101. The first sound absorbing film 114 and the second sound absorbing film 115 constitute a sound absorbing ring as shown in fig. 2. The ultrasound signal is induced by the variable acoustic impedance module 110 from the side of the cylinder structure in such a way that the orientation of the body surface of the implantable cardiac pacemaker 100 is not critical and is not affected by the implantation site. It should be noted that the shapes and positions of the piezoelectric film 112, the variable acoustic impedance film 111, the first acoustic absorbing film 114, and the second acoustic absorbing film 115 in fig. 2 and 3 are merely examples, and any one of them may take other shapes and/or positions in other embodiments. Backing 113 may comprise the same material as housing 101 of implantable cardiac pacemaker 100, such as titanium. The sound absorbing ring is made of silicon oxide or other materials.

Fig. 4 is a flow chart of communication between an implantable cardiac pacemaker and a programming device according to one embodiment of the present invention. Referring to fig. 2 to 4, in the embodiment of the present invention, a signal processing module in the implantable cardiac pacemaker 100 is denoted as a signal processing module 120, and the signal processing module 120 may include a processor 121 and an ADC unit 122, where the ADC unit 122 is configured to convert an electrical signal (e.g., an analog signal) sent by the variable acoustic impedance module 110 (e.g., sent by the piezoelectric film 112) into a digital signal, and send the digital signal to the processor 121. The processor 121 also employs a processor for controlling pacing functions in the implantable cardiac pacemaker 100 to conserve volume. The processor 121 may comprise logically separable software (computer programs), hardware, or equivalent components. The processor 121 is, for example, a chip. The specific structure of the processor is not particularly limited in this embodiment.

The processor 121 may generate a feedback signal according to the received electrical signal and may transmit data stored or sensed by the implantable cardiac pacemaker 100 to the outside. In order to change the acoustic impedance of the variable acoustic impedance module 110 when the feedback signal or data is externally transmitted, in an embodiment, the signal processing module 120 may further include a DAC unit 123, and the DAC unit 123 may be configured to convert a signal (digital signal) for changing the acoustic impedance transmitted from the processor 121 into an analog signal and transmit the analog signal to the variable acoustic impedance module 110 (specifically, to the variable acoustic impedance film 111), and the variable acoustic impedance module 110 may adjust the acoustic impedance according to the analog signal transmitted from the DAC unit 123. Referring to fig. 2, one electrode (e.g., positive electrode, denoted by "+") of the piezoelectric film 112 is connected to the processor 121 through the ADC unit 122, and the other electrode (e.g., negative electrode, denoted by "-") is also connected to the processor 121 to form a loop. One electrode (e.g., positive electrode, denoted by "+") of the variable acoustic impedance film 111 is connected to the processor 121 through the DAC unit 123, and the other electrode (e.g., negative electrode, denoted by "-") is also connected to the processor 121 to form a loop. The ADC unit 122 and the DAC unit 123 may be implemented by different devices, respectively, or may be implemented by the same device, which is not particularly limited in this embodiment.

The implantable cardiac pacemaker 100 according to the embodiment of the present invention senses an ultrasonic signal by using the variable acoustic impedance module 110 on one hand, and can acquire data from the outside by using the ultrasonic signal, and generates a corresponding ultrasonic reflection signal by changing the acoustic impedance of the variable acoustic impedance module 110 on the other hand, and can transmit data to the outside by using the ultrasonic reflection signal. In an embodiment, the implantable cardiac pacemaker 100 is a leadless pacemaker, the leadless pacemaker does not need to be connected with a wire, the volume is small, when the ultrasonic signal and the ultrasonic reflection signal are adopted to communicate with the outside, communication can be initiated by the ultrasonic transmitting and receiving equipment located outside the body at any time according to the need, the real-time performance is high, communication can be performed based on the mode that the acoustic impedance of the implanted end is changed under single-source ultrasound, the volume of the leadless pacemaker does not need to be obviously increased, the requirement on the battery capacity is low, and the circuit structure and the battery capacity requirement on the implanted end in the communication process are low.

The embodiment of the invention also comprises a program control device through which a user can set and read the parameters and stored data of the implantable cardiac pacemaker 100. Referring to fig. 1 and 4, in an embodiment of the present invention, the programmable device 200 includes a programmable device host 210 and an ultrasonic programmable head 220, which may be connected by a cable. The ultrasound control head 220 is configured to send an ultrasound signal and sense an ultrasound reflection signal, for example, the ultrasound signal may be sent under the control of the control host 210, and may sense an ultrasound reflection signal obtained after the sent ultrasound signal is reflected by an object at a target position (here, the variable acoustic impedance module 110 in the implantable cardiac pacemaker 100), where the ultrasound reflection signal may be converted into a corresponding electrical signal and then sent to the control host 210. The main body 210 of the program control instrument transmits data to the implantable cardiac pacemaker through an ultrasonic signal sent by the ultrasonic program control head 220, obtains the acoustic impedance state of the implantable cardiac pacemaker through an ultrasonic reflection signal sensed by the ultrasonic program control head 220, and obtains the data of the implantable cardiac pacemaker 100 according to the change of the acoustic impedance state, namely, the function of communicating with the implantable cardiac pacemaker is realized by adopting a single-source ultrasonic mode. The programmable controller 210 may include a control system, a display, and input/output devices, etc., where the ultrasonic signals and the ultrasonic reflected signals are pulse signals, for example, to facilitate data transmission. The specific structures of the sequencer host 210 and the ultrasonic sequencer head 220 are not particularly limited in this embodiment.

The program control device 200 of the embodiment of the invention adopts the ultrasonic signal and the ultrasonic reflection signal for communication instead of adopting human tissues as the medium for current conduction, so that the device is not influenced by the cardiac cycle, can be initiated by external ultrasonic transmitting and receiving equipment at any time according to the requirement, and has high real-time performance.

As shown in fig. 1, the cardiac pacing system according to the embodiment of the present invention includes the above-described implantable cardiac pacemaker 100 and the program control device 200.

Still referring to fig. 4, for example, the data transmission between implantable cardiac pacemaker 100 and programmable device 200 in the cardiac pacing system may include the following processes: when the user needs to program data to the implantable cardiac pacemaker 100, the program control instrument host 210 prepares related data, the data is converted into an ultrasonic signal through the ultrasonic program control head 220, the variable acoustic impedance module 110 senses the ultrasonic signal and the change thereof and sends a corresponding analog electric signal to the signal processing module 120, the signal processing module 120 converts the ultrasonic signal into a digital signal through the ADC unit 122 and transmits the digital signal to the processor 121, so that the transmission from outside to inside is realized, and the transmission from outside to inside is realized as shown in a flow A in fig. 4; when the device is used for reading data stored in the implantable cardiac pacemaker 100, the ultrasonic programming head 220 firstly transmits an ultrasonic signal, the processor 121 firstly receives a corresponding instruction through the same path as the process A, the processor 121 transmits the data to the ultrasonic programming head 220 based on the instruction, the digital signal transmitted by the processor 121 is converted into an analog signal through the DAC unit 123, the acoustic impedance of the variable acoustic impedance module 110 is changed under the action of the analog signal, at the moment, the ultrasonic reflection signal formed by the variable acoustic impedance module 110 of the ultrasonic signal transmitted by the ultrasonic programming head 220 is changed, the ultrasonic programming head 220 senses the changed ultrasonic reflection signal and converts the ultrasonic reflection signal into a corresponding electric signal, and then the data is returned to the programmable controller host 210, so that the transmission from inside to outside of the body is realized, as shown in the process B in fig. 4.

In the cardiac pacing system, when the implantable cardiac pacemaker 100 transmits a feedback signal or data to the outside, in order to change the acoustic impedance of the variable acoustic impedance module 110, in an embodiment, the signal processing module in the implantable cardiac pacemaker 100 may control the variable acoustic impedance film 111 to be powered on or off, and the variable acoustic impedance film 111 may exhibit different acoustic impedances when powered on or off, so that the acoustic impedance of the variable acoustic impedance module 110 may also be changed by the operation of powered on or off.

Communication data transmitted between implantable cardiac pacemaker 100 and programming device 200 is illustratively described below.

In one embodiment, when the acoustic impedance of the variable acoustic impedance module 110 in the implantable cardiac pacemaker 100 is unchanged when the acoustic impedance of the device 200 receives the reflected ultrasonic signal reflected from the body, the device 200 records the corresponding acoustic impedance state as a first level, and when the acoustic impedance of the variable acoustic impedance module 110 is changed, the device 200 records the corresponding acoustic impedance state as a second level opposite to the first level. For example, it may be provided that the acoustic impedance state of the variable acoustic impedance film 111 when it is detected from the ultrasonic programming head 220 that it is not energized is set to 0 and that the acoustic impedance state when a current is passed is set to 1.

In one embodiment, when the variable acoustic impedance module 110 does not sense the ultrasonic signal sent by the programmable device 200, the processor 121 uses a first level as the level of the ultrasonic signal, and when the variable acoustic impedance module 110 senses the ultrasonic signal sent by the programmable device 200, the processor 121 uses a second level as the level of the ultrasonic signal, and the second level is opposite to the first level. For example, when the piezoelectric film 112 senses an ultrasonic signal emitted by the ultrasonic programming head 220, the processor 121 obtains a voltage change, which is denoted as 1, and when the ultrasonic signal is not sensed, no voltage or no voltage change is denoted as 0. The above communication mode is implemented by the ultrasonic program control head 220, the transmission and sensing of ultrasonic signals are completed, the data in the communication process can be pulse signals, and the pulse width can be adjusted according to actual requirements. The coding mode only considers whether the voltage signal is changed or not, and has low precision requirements on the ADC unit 122 and the DAC unit 123, thereby being convenient for system design and integration. The invention is not limited in this regard and in other embodiments other communication signal arrangements may be employed.

The data transmitted between implantable cardiac pacemaker 100 and programmable device 200 are transmitted, for example, periodically. The data transmitted in each communication cycle is called a communication frame, and each communication frame includes a frame head end and frame data, and can be initiated by the external program control instrument host 210 through the ultrasonic program control head 220. To avoid interference or false sensing by implantable cardiac pacemaker 100, communication may be via a set sequence. Fig. 5 is a schematic diagram of a communication frame for data transmission between implantable cardiac pacemaker 100 and programming device 200 according to one embodiment of the present invention. Referring to fig. 5, data segments are numbered for convenience of explanation. The number 1 example consists of 5bit binary data representing the sequence of ultrasonic signals sent by the ultrasonic programming head 220. Number 2 is information that changes the acoustic impedance when the processor 121 receives this sequence, an example consisting of 3bit binary data. After transmitting the data of number 1 and number 2 and after the ultrasound programming head 220 senses the response data of the processor 121, number 3 is transmitted, with number 3 representing which end of the communication is transmitting data. By way of example, 01 represents the need for the programming apparatus 200 to communicate data. 10 represent the transfer of data by the implantable cardiac pacemaker 100. When the transmission of the frame head end data is completed, the transmission of the frame data is started. The frame data includes a data segment 4 (for example, 8 bits) indicating the length of the whole frame data, a data segment 5 indicating a checksum (checksum), and a data segment 5 indicating data to be transmitted when communication is performed. If the implantable cardiac pacemaker 100 does not have data to deliver, a reply of 0xFF (frame data length) may be set to end the communication.

The cardiac pacing system is based on single-source ultrasound, and can detect the change of acoustic impedance of the variable acoustic impedance module 110 in the implantable cardiac pacemaker 100 by using the program control device 200 in vitro, and can realize passive communication from the implantable cardiac pacemaker 100 to the program control device 200 by using the change of acoustic impedance as an information carrier, and meanwhile, the variable acoustic impedance module 110 can sense an ultrasonic signal and realize conversion from the ultrasonic signal to an electric signal, so that in vitro to in vivo communication can be realized, namely duplex communication can be realized. Because the ultrasonic signal and the ultrasonic reflection signal are adopted for communication, rather than adopting human tissues as a medium for current conduction, the method is not influenced by a cardiac cycle, communication can be initiated by external ultrasonic transmitting and receiving equipment at any time according to the need, the instantaneity is high, the requirements on the circuit structure and the battery capacity of an implanted end in the communication process are low, and the miniaturization of the implanted cardiac pacemaker is facilitated.

The implantable cardiac pacemaker 100 is, for example, a leadless pacemaker. Because the leadless pacemaker does not adopt a wire and has higher requirement on volume, compared with an HBC communication mode, the communication process is not influenced by a cardiac cycle by utilizing the communication device, and can be initiated by the program control instrument host 210 through the ultrasonic program control head 220 at any time, the real-time performance is high, moreover, because the MEMS processing technology is mature, the variable acoustic impedance film 111 and the piezoelectric film 112 with smaller size can be processed, and the precision requirements on the ADC unit 122 and the DAC unit 123 are not high by adopting the communication mode, so that the circuit complexity of a packaging module of the leadless cardiac pacemaker is lower and the power consumption is also lower.

It should be noted that, in the present specification, each embodiment is described in a progressive manner, and each embodiment is mainly described in a different manner from other embodiments, and identical and similar parts between the embodiments are referred to each other.

The foregoing description is only illustrative of the preferred embodiments of the present invention, and is not intended to limit the scope of the claims, and any person skilled in the art may make any possible variations and modifications to the technical solution of the present invention using the method and technical content disclosed above without departing from the spirit and scope of the invention, so any simple modification, equivalent variation and modification made to the above embodiments according to the technical matter of the present invention fall within the scope of the technical solution of the present invention.

Claims

1. The implantable cardiac pacemaker is characterized by comprising a variable acoustic impedance module and a signal processing module, wherein the variable acoustic impedance module is used for sensing an ultrasonic signal, converting the ultrasonic signal into a corresponding electric signal and then sending the corresponding electric signal to the signal processing module, and the acoustic impedance of the variable acoustic impedance module can be changed under the control of the signal processing module and generates a corresponding ultrasonic reflection signal; the ultrasound signal and the ultrasound reflected signal are used by the implantable cardiac pacemaker to communicate with the outside.

2. The implantable cardiac pacemaker of claim 1, wherein the variable acoustic impedance module comprises a variable acoustic impedance film electrically connected to the signal processing module; the acoustic impedance of the variable acoustic impedance film is different according to different signals of the signal processing module, and the acoustic impedance of the variable acoustic impedance film generates corresponding ultrasonic reflection signals according to the signals of the signal processing module.

3. The implantable cardiac pacemaker of claim 2, wherein the variable acoustic impedance module further comprises a piezoelectric film electrically coupled to the signal processing module, the piezoelectric film configured to sense the ultrasonic signal and convert the ultrasonic signal to a corresponding electrical signal for transmission to the signal processing module.

4. An implantable cardiac pacemaker as recited in claim 3 further comprising a housing, the housing being disposed outside the variable acoustic impedance module and the signal processing module, the variable acoustic impedance module further comprising a backing disposed on an inner surface of the housing, the piezoelectric film and the variable acoustic impedance film being arranged in spaced relation on the backing.

5. The implantable cardiac pacemaker of claim 4, wherein the variable acoustic impedance module further comprises a first acoustic absorbing membrane and a second acoustic absorbing membrane, the first acoustic absorbing membrane being positioned between the piezoelectric membrane and the variable acoustic impedance membrane, the second acoustic absorbing membrane being positioned on a side of the variable acoustic impedance membrane remote from the annular piezoelectric membrane.

6. An implantable cardiac pacemaker as recited in claim 5 in which the piezoelectric film, the variable acoustic impedance film, the first acoustic absorbing film and the second acoustic absorbing film are each of annular configuration with their axes parallel.

7. The implantable cardiac pacemaker of claim 6, wherein a width of the first acoustic absorbing film is different than a width of the second acoustic absorbing film and each is different than a width of the variable acoustic impedance film.

8. The implantable cardiac pacemaker of claim 2, wherein the signal processing module changes an acoustic impedance of the variable acoustic impedance module by powering on or off the variable acoustic impedance film.

9. The implantable cardiac pacemaker of claim 1, wherein the signal processing module comprises a processor, an ADC unit, and a DAC unit; the ADC unit is used for converting the electric signal sent by the variable acoustic impedance module into a digital signal and sending the digital signal to the processor; the DAC unit is used for converting the signal which is sent by the processor and used for changing the acoustic impedance into an analog signal and sending the analog signal to the variable acoustic impedance module, and the variable acoustic impedance module adjusts the acoustic impedance according to the analog signal sent by the DAC unit.

10. The implantable cardiac pacemaker of claim 1, wherein the implantable cardiac pacemaker is a leadless pacemaker.

11. The program control device is characterized by comprising a program control instrument host and an ultrasonic program control head; the ultrasonic program control head is used for sending ultrasonic signals and sensing ultrasonic reflection signals; the main machine of the program control instrument transmits data to the implantable cardiac pacemaker through an ultrasonic signal sent by the ultrasonic program control head, obtains the acoustic impedance state of the implantable cardiac pacemaker through an ultrasonic reflection signal perceived by the ultrasonic program control head, and obtains the data of the implantable cardiac pacemaker according to the change of the acoustic impedance state.

12. A cardiac pacing system comprising an implantable cardiac pacemaker as claimed in any one of claims 1 to 10 and a programmable device as claimed in claim 11.