WO2023185606A1

WO2023185606A1 - Implantable cardiac pacemaker, program control apparatus, and cardiac pacing system

Info

Publication number: WO2023185606A1
Application number: PCT/CN2023/083250
Authority: WO
Inventors: 张建锋
Original assignee: 创领心律管理医疗器械（上海）有限公司
Priority date: 2022-04-01
Filing date: 2023-03-23
Publication date: 2023-10-05
Also published as: CN116920278A

Abstract

An implantable cardiac pacemaker, a program control apparatus, and a cardiac pacing system. In an aspect, the implantable cardiac pacemaker uses a variable acoustic impedance module to sense an ultrasonic signal, and acquires data from the outside by means of the ultrasonic signal, and in another aspect, the acoustic impedance of the variable acoustic impedance module is changed to generate a corresponding ultrasonic reflection signal, and the data are sent to the outside by means of the ultrasonic reflection signal. The implantable cardiac pacemaker communicates in a mode of acoustic impedance changes at an implanted end under a single source ultrasound.

Description

Implantable pacemakers, programmable devices and cardiac pacing systems

Technical field

The present invention relates to the medical field, and in particular to an implantable cardiac pacemaker, a program-controlled device and a cardiac pacing system.

Background technique

The implantable pacemaker is a major contribution of modern biomedical engineering to mankind. The implantable pacemaker allows patients with severe arrhythmias who were ineffective in drug treatment in the past to be treated. The use of pacemakers has successfully treated chronic arrhythmia. While arrhythmias have saved the lives of thousands of patients, pacemakers are also used in tachyarrhythmias and non-cardiac diseases, such as the prevention of paroxysmal atrial tachyarrhythmia, carotid sinus syncope, and biventricular synchrony. Treatment of drug-refractory congestive heart failure has significantly reduced cardiovascular disease mortality.

With the development of technology and applications, modern implantable pacemakers need to have the function of duplex communication with the outside world, such as program control and wireless telemetry of the pacemaker implanted in the body by external equipment. At the same time, pacemakers are also improving in terms of lightweighting and miniaturization. For example, the implantable leadless pacemaker has been developed, which has the advantages of reducing complications, less trauma, easy implantation, and compatible with MRI. , is the future development direction of pacing technology.

However, implantable leadless pacemakers cannot fully use wireless communication methods such as magnetic coils and radio frequency (RF) used by traditional pacemakers due to their small size and small battery capacity. According to public information, HBC (Human Body Communication) is an optional communication method for implantable leadless cardiac pacemakers. It uses human tissue as the medium for current conduction, by sending electrical pulses or collecting electrical current at the pacemaker electrode terminals. Pulse signals collect or send electrical pulse signals on the surface of the human body for program control and remote measurement. However, when using HBC communication, in order to avoid affecting the normal rhythm function of the heart and the normal pacing function, communication needs to be completed during the refractory period, which makes it impossible to transmit some real-time event signals (such as endocardial event signals) in real time. In addition, in order to avoid interference during transmission, HBC usually uses frequency shift keying and other methods to modulate and demodulate. The circuit is relatively complex and the power consumption is high, and there are still problems in application.

Contents of the invention

In order to improve the real-time communication between the implanted cardiac pacemaker and the outside, the present invention provides an implantable cardiac pacemaker, a program-controlled device and a cardiac pacing system.

On the one hand, the present invention provides an implantable cardiac pacemaker, which includes a variable acoustic impedance module and a signal processing module. The variable acoustic impedance module is used to sense ultrasonic signals and convert the ultrasonic signals into corresponding electrical signals. Sent to the signal processing module, the acoustic impedance of the variable acoustic impedance module can be changed under the control of the signal processing module, and a corresponding ultrasonic reflection signal is generated; the ultrasonic signal and the ultrasonic reflection signal are used for The implantable pacemaker communicates with the outside world.

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 varies according to different signals from the signal processing module, and the variable acoustic impedance film The acoustic impedance of the impedance film generates a corresponding ultrasonic reflection signal according to the signal of the signal processing module.

Optionally, the variable acoustic impedance module also includes a piezoelectric film electrically connected to the signal processing module. The piezoelectric film is used to sense the ultrasonic signal and convert the ultrasonic signal into a corresponding electrical signal. and then sent to the signal processing module.

Optionally, the implantable cardiac pacemaker further includes a shell, the shell is set outside the variable acoustic impedance module and the signal processing module, the variable acoustic impedance module further includes a backing, the A backing is provided on the inner surface of the housing, and the piezoelectric film and the variable acoustic impedance film are arranged in zones on the backing.

Optionally, the variable acoustic impedance module further includes a first sound absorbing film and a second sound absorbing film, the first sound absorbing film is located between the piezoelectric film and the variable acoustic impedance film, and the third sound absorbing film is located between the piezoelectric film and the variable acoustic impedance film. Two sound-absorbing films are located on the side of the variable acoustic impedance film away from the piezoelectric film.

Optionally, the piezoelectric film, the variable acoustic impedance film, the first sound-absorbing film and the second sound-absorbing film are all annular structures, and their axes are parallel.

Optionally, the width of the first sound-absorbing film is different from the width of the second sound-absorbing film, and both are 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 energizing or de-energizing 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 to convert the electrical signal sent by the variable acoustic impedance module into a digital signal and send it to the processor; The DAC unit is used to convert the signal sent by the processor for changing the acoustic impedance into an analog signal and send it to the variable acoustic impedance module. The variable acoustic impedance module adjusts according to the analog signal sent by the DAC unit. Acoustic impedance.

Optionally, the implantable cardiac pacemaker is a leadless pacemaker.

On the one hand, the present invention provides a program-controlled device. The program-controlled device includes a program-controlled instrument host and an ultrasonic program-controlled head; the ultrasonic program-controlled head is used to send ultrasonic signals and sense ultrasonic reflection signals; the program-controlled instrument host is controlled by the ultrasonic program The ultrasonic signal emitted by the head transmits data to the implanted cardiac pacemaker, and the acoustic impedance state of the implanted cardiac pacemaker is obtained through the ultrasonic reflection signal sensed by the ultrasonic programming control head. According to the acoustic impedance state Changes to acquire data from the implantable pacemaker.

In one aspect, the present invention provides a cardiac pacing system, which includes the above-mentioned implantable cardiac pacemaker and a program-controlled device.

The implantable cardiac pacemaker provided by the present invention includes a variable acoustic impedance module and a signal processing module. The variable acoustic impedance module is used to sense ultrasonic signals, convert the ultrasonic signals into corresponding electrical signals and send them to the Signal processing module, the acoustic impedance of the variable acoustic impedance module can be changed under the control of the signal processing module and generate a corresponding ultrasonic reflection signal; the ultrasonic signal and the ultrasonic reflection signal are used for the implantable heart The pacemaker communicates with the outside world. On the one hand, the implantable cardiac pacemaker uses a variable acoustic impedance module to sense the ultrasonic signal, and the ultrasonic signal can be used to obtain data from the outside. On the other hand, by changing the acoustic impedance of the variable acoustic impedance module, the corresponding Ultrasonic reflection signal, which can be used to send data to the outside. Because ultrasonic signals and ultrasonic reflection signals are used for communication instead of using human tissue as the medium for current conduction, it is not affected by the cardiac cycle and can be used at any time as needed. External ultrasound sending and receiving equipment initiates communication with high real-time performance. Moreover, the implantable cardiac pacemaker communicates based on the change of acoustic impedance of the implanted end under single-source ultrasound. The communication process has low requirements on the circuit structure and battery capacity of the implanted end, which is convenient for the implanted cardiac pacemaker. Miniaturization, such as leadless pacemakers.

In the program-controlled device provided by the present invention, the ultrasonic program-controlled head can send ultrasonic signals and sense ultrasonic reflections. The program controller host transmits data to the implanted cardiac pacemaker through the ultrasonic signal, and obtains the acoustic impedance state of the implanted cardiac pacemaker through the ultrasonic reflection signal sensed by the ultrasonic program control head. , the data of the implantable cardiac pacemaker is obtained according to the change of the acoustic impedance state. Since ultrasonic signals and ultrasonic reflection signals are used for communication instead of using human tissue as the medium for current conduction, it is not affected by the cardiac cycle. Impact, communication can be initiated by external ultrasonic sending and receiving equipment at any time as needed, with high real-time performance.

The cardiac pacing system provided by the present invention includes the above-mentioned implantable cardiac pacemaker and a program-controlled device, which can realize real-time communication with external equipment, and the communication process has low requirements on the circuit structure and battery capacity of the implanted end, which is convenient for implantation. Miniaturization of pacemakers.

Description of drawings

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

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

FIG. 3 is a schematic diagram of a partial area of the implantable cardiac pacemaker shown in FIG. 2 .

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

FIG. 5 is a schematic diagram of a communication frame used for data transmission between the implantable cardiac pacemaker 100 and the program control device 200 according to an embodiment of the present invention.

Explanation of reference symbols:
100-Implantable cardiac pacemaker; 101-Shell; 110-Variable acoustic impedance module; 111-Variable acoustic impedance film; 112-Piezoelectric film; 113-Backing; 114-First sound-absorbing film; 115-No. 2. Sound-absorbing film; 120-signal processing module; 121-processor; 122-ADC unit; 123-DAC unit; 200-program control device; 210-program control instrument host; 220-ultrasonic program control head.

Detailed ways

The implantable cardiac pacemaker, programmable device and cardiac pacing system of the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become clearer from the following description. It should be understood that the drawings in this specification are in a very simplified form and use non-precise terms. The precise proportions are only used to conveniently and clearly assist the purpose of explaining the embodiments of the present invention.

Figure 1 is a schematic diagram of a cardiac pacing system according to an embodiment of the present invention. Referring to Figure 1, an embodiment of the present invention relates to an implantable cardiac pacemaker 100, a program-controlled device 200 and a cardiac pacing system. The cardiac pacing system includes the implanted cardiac pacemaker 100 and a program-controlled device. Device 200, when the cardiac pacing system is working, the implantable cardiac pacemaker 100 is implanted in the body, the program control device 200 is located outside the body, and the implantable cardiac pacemaker 100 and the program control device 200 can use ultrasound signals and Ultrasonic reflection signals communicate to meet the needs of program control and telemetry. It can be used in situations such as doctors or patients modifying the parameters of implanted medical devices through in vitro program settings, or reading data stored by implanted medical devices during work. . Specific instructions are as follows.

The implantable cardiac pacemaker 100 according to the embodiment of the present invention includes a variable acoustic impedance module 110 and a signal processing module (not shown in Figure 1) provided in the housing; the variable acoustic impedance module 110 is used to sense ultrasound signals, and Convert the ultrasonic signal into a corresponding electrical signal and send it to the signal processing module; the acoustic impedance of the variable acoustic impedance module 110 can be changed under the control of the signal processing module and generate a corresponding ultrasonic reflection signal; The ultrasonic signal and the ultrasonic reflection signal are used for the implantable cardiac pacemaker 100 to communicate with the outside. On the one hand, the implantable cardiac pacemaker 100 uses the variable acoustic impedance module 110 to sense ultrasonic signals, and the ultrasonic signals can be used to obtain data from the outside. On the other hand, by changing the acoustic impedance of the variable acoustic impedance module 110, it generates corresponding ultrasonic signals. The ultrasonic reflection signal changes with the change of the acoustic impedance of the variable acoustic impedance module 110, and the ultrasonic reflection signal can be used to transmit data to the outside.

Figure 2 is a schematic diagram of an implantable cardiac pacemaker according to an embodiment of the present invention. FIG. 3 is a schematic diagram of a partial area of the implantable cardiac pacemaker shown in FIG. 2 . Referring to FIGS. 2 and 3 , in one embodiment, the variable acoustic impedance module 110 in the implantable cardiac pacemaker 100 may include a variable acoustic impedance film 111 , and the variable acoustic impedance film 111 is consistent with the variable acoustic impedance module 110 . The signal processing module is electrically connected. The acoustic impedance of the variable acoustic impedance film 111 is different according to different signals of the signal processing module. The acoustic impedance of the variable acoustic impedance film 111 generates 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 also includes a piezoelectric film 112 electrically connected to the signal processing module. The piezoelectric film 112 is used to sense ultrasonic signals and convert the sensed ultrasonic signals into corresponding electrical signals. Send later to the signal processing module.

Both 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 side surface of the piezoelectric layer, and a first electrode disposed on the other side surface of the piezoelectric layer. The second electrode, the piezoelectric layer can be made of polyvinylidene fluoride (PVDF), aluminum nitride (AlN), zinc oxide (ZnO), lead zirconate titanate (PZT), lithium niobium oxide (LiNbO3), tantalum oxide Lithium (LiTaO3), or one or more of other piezoelectric materials.

In the embodiment shown in FIGS. 2 and 3 , the variable acoustic impedance module 110 uses a variable acoustic impedance film 111 to generate an ultrasonic reflection signal, and additionally uses a piezoelectric film 112 to sense the ultrasonic signal, so that the variable acoustic impedance film 11 and the piezoelectric film 112 The signal processing processes do not interfere with each other. The signal processing module can send another electrical signal to the variable acoustic impedance film 111 while receiving the electrical signal generated by the piezoelectric film 112 based on the sensed ultrasonic signal, so it can achieve full dual Industrial communications. The present invention is not limited to this. In another embodiment, the variable acoustic impedance module 110 may not be provided with the piezoelectric film 112 , but may use the variable acoustic impedance film 111 for generating ultrasonic reflection signals to sense the ultrasonic signal, and use the variable acoustic impedance film 111 to generate the ultrasonic reflection signal. The ultrasonic signal is converted into a corresponding electrical signal and then sent to the signal processing module. The process of processing the ultrasonic signal by the variable acoustic impedance film 111 and the process of generating the ultrasonic reflection signal can be performed in a time-sharing manner.

Referring to FIGS. 1 to 3 , the implantable cardiac pacemaker 100 may further include a housing 101 , which is set outside the variable acoustic impedance module 110 and the signal processing module. The variable acoustic impedance module 110 may further include a backing 113 disposed on the inner surface of the housing 101 , and the piezoelectric film 112 and the variable acoustic impedance film 111 are arranged in zones on the backing 113 . Ultrasonic signals from the outside reach the backing 113 and are sensed by the piezoelectric film 112 .

The variable acoustic impedance module 110 may further include a first sound-absorbing film 114 and a second sound-absorbing film 115 , which are, for example, located on the 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 them. The second sound-absorbing film 115 is located on the side of the variable acoustic impedance film 111 away from the piezoelectric film 112 . The first sound-absorbing film 114 and the second sound-absorbing film 115 are used to determine the emission position of the ultrasonic reflection signal, and then find and detect the state of the variable acoustic impedance film 111 based on the emission position. The width direction of the first sound absorbing film 114 and the second sound absorbing film 115 is along the arrangement direction of the piezoelectric film 112 and the variable acoustic impedance film 111 . In order to improve the positioning accuracy, the first sound-absorbing film 114 can be provided The width of is different from the width of the second sound-absorbing film 115, and both are different from the width of the variable acoustic impedance film 111. As shown in Figure 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 smaller than the width of the variable acoustic impedance film 111, but is not limited thereto. , in another embodiment, the width of the second sound-absorbing film 115 is smaller than the width of the variable acoustic impedance film 111 , and the width of the first sound-absorbing film 114 is larger than the width of the variable acoustic impedance film 111 .

Considering that the penetration, reflection and refraction of ultrasonic waves in the body are relatively complex, and when the implantable pacemaker 100 is implanted in the human body, its face facing the human chest is not easy to control. Therefore, in order to facilitate ultrasonic positioning, the implanted pacemaker 100 is The housing 101 of the implantable pacemaker 100 can be a cylindrical structure as shown in Figure 2 (for example, a cylindrical structure, the outer surface of the cylindrical structure is a cylindrical surface), and the battery of the implantable pacemaker 100 can be configured within the column structure. The variable acoustic impedance module 110 can be arranged in the column structure using a hollow ring structure, and the hollow can be fed through the electrodes. For example, the above-mentioned piezoelectric film 112, variable acoustic impedance film 111, first sound-absorbing film 114 and second sound-absorbing film 115 can be connected end to end in the housing 101, that is, they are all arranged in a ring structure. The piezoelectric film 112 The axes of the variable acoustic impedance film 111, the first sound absorbing film 114 and the second sound absorbing film 115 are, for example, parallel. The axis of the annular 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 form a sound-absorbing ring as shown in FIG. 2 . The ultrasonic signal is sensed by the variable acoustic impedance module 110 from the side of the above-mentioned cylindrical structure. This method does not have high requirements on the orientation of the implantable pacemaker 100 and is not affected by the implantation position. It should be noted that the shapes and positions of the piezoelectric film 112, the variable acoustic impedance film 111, the first sound-absorbing film 114 and the second sound-absorbing film 115 in Figures 2 and 3 are only examples. In other embodiments, Any of them may adopt other shapes and/or positions. The backing 113 may comprise the same material as the housing 101 of the implantable pacemaker 100, such as titanium. The sound-absorbing ring is made of silicon oxide or other materials, for example.

Figure 4 is a flow chart of communication between an implantable cardiac pacemaker and a programmable device according to an embodiment of the present invention. Referring to Figures 2 to 4, in the embodiment of the present invention, the signal processing module in the implantable cardiac pacemaker 100 is denoted as signal processing module 120. The signal processing module 120 may include a processor 121 and an ADC unit 122. The ADC unit 122 is used to convert an electrical signal (eg, an analog signal) sent by the variable acoustic impedance module 110 (eg, sent by the piezoelectric film 112 ) into a digital signal, and send it to the processor 121 . The processor 121 also uses the implantable cardiac pacemaker 100 to control the pacing function. capable processor to save space. The processor 121 may include logically separable software (computer program), 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 can generate a feedback signal according to the received electrical signal, and can send the data stored or sensed by the implantable pacemaker 100 to the outside. When sending the 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 120 may also include a DAC unit 123, the DAC unit 123 is used to convert the processor The signal (which is a digital signal) sent by 121 for changing the acoustic impedance is converted into an analog signal and sent to the variable acoustic impedance module 110 (specifically sent to the variable acoustic impedance film 111). The variable acoustic impedance module 110 can be configured according to the DAC unit. The analog signal sent by 123 adjusts the acoustic impedance. Referring to FIG. 2 , one electrode (such as the positive electrode, represented by “+”) of the piezoelectric film 112 is connected to the processor 121 through the ADC unit 122 , and the other electrode (such as the negative electrode, represented by “-”) is also connected to the processor 121 Connect to form a loop. One electrode (such as the positive electrode, represented by "+") of the variable acoustic impedance film 111 is connected to the processor 121 through the DAC unit 123, and the other electrode (such as the negative electrode, represented by "-") is also connected to the processor 121, so as to Form a loop. The ADC unit 122 and the DAC unit 123 may be implemented by different devices, or may be implemented by the same device, which is not particularly limited in this embodiment.

The implantable cardiac pacemaker 100 in the embodiment of the present invention, on the one hand, uses the variable acoustic impedance module 110 to sense ultrasonic signals, and the ultrasonic signals can be used to obtain data from the outside. On the other hand, by changing the acoustic impedance of the variable acoustic impedance module 110, A corresponding ultrasonic reflection signal is generated, which can be used to send data to the outside. In one embodiment, the implantable cardiac pacemaker 100 is a leadless pacemaker. The leadless pacemaker does not need to be connected to wires and is small in size. When using the above-mentioned ultrasonic signals and ultrasonic reflection signals to communicate with the outside, it can not only Communication is initiated by the ultrasound transmitting and receiving equipment located outside the body at any time as needed, which is highly real-time and can communicate based on changes in the acoustic impedance of the implanted end under single-source ultrasound without significantly increasing the size of the leadless pacemaker. The requirements for battery capacity are low, and the communication process has low requirements for the circuit structure and battery capacity of the implanted end.

Embodiments of the present invention also include a program-controlled device through which a user can set and read parameters and stored data of the above-mentioned implantable pacemaker 100. Referring to Figures 1 and 4, in the embodiment of the present invention, the program control device 200 includes a program control instrument host 210 and an ultrasonic program control head 220, both of which can be connected via cables. connect. The ultrasonic program control head 220 is used to send ultrasonic signals and sense ultrasonic reflection signals. For example, it can send out ultrasonic signals under the control of the program controller host 210 and can also sense the object (here, a plant) where the emitted ultrasonic signal passes through the target position. The ultrasonic reflection signal obtained after reflection by the variable acoustic impedance module 110 in the implantable cardiac pacemaker 100 can be converted into a corresponding electrical signal and then sent to the program controller host 210. The program controller host 210 transmits data to the implanted cardiac pacemaker through the ultrasonic signal sent by the ultrasonic program control head 220, and obtains the acoustic impedance of the implanted cardiac pacemaker through the ultrasonic reflection signal sensed by the ultrasonic program control head 220. state, and the data of the implantable cardiac pacemaker 100 is obtained according to the change in the acoustic impedance state, that is, the single-source ultrasound mode is used to realize the function of communicating with the implanted cardiac pacemaker. The program controller host 210 may include a control system, a display, an input and output device, etc. The ultrasonic signal and the ultrasonic reflection signal are, for example, pulse signals to facilitate data transmission. In this embodiment, the specific structures of the program controller host 210 and the ultrasonic program control head 220 are not particularly limited.

The program-controlled device 200 in the embodiment of the present invention uses ultrasonic signals and ultrasonic reflection signals for communication instead of using human tissue as the medium for current conduction. Therefore, it is not affected by the cardiac cycle and can initiate communication at any time by external ultrasonic sending and receiving equipment as needed. , high real-time performance.

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

Still referring to FIG. 4 , as an example, the data transmission between the implanted cardiac pacemaker 100 and the programming device 200 in the cardiac pacing system may include the following process: when the user needs to program data to the implanted cardiac pacemaker 100 At this time, the program controller host 210 prepares relevant data and converts the data into ultrasonic signals through the ultrasonic program control head 220. The variable acoustic impedance module 110 senses the ultrasonic signals and their changes, and sends corresponding analog electrical signals to the signal processing module 120. Signal processing The module 120 converts it into a digital signal through the ADC unit 122 and transmits it to the processor 121, thereby realizing the transmission of data from outside the body to the body, as shown in process A in Figure 4; when it is necessary to read the implanted cardiac pacing When receiving the data stored in the processor 100, the ultrasonic program control head 220 first sends an ultrasonic signal, the processor 121 first receives the corresponding instruction through the same path as process A, and sends data to the ultrasonic program control head 220 based on the instruction. The processor 121 sends The digital signal is converted into an analog signal through the DAC unit 123. Under the action of the analog signal, the acoustic impedance of the variable acoustic impedance module 110 changes. At this time, the ultrasonic signal sent by the ultrasonic program control head 220 is reflected by the ultrasonic reflection formed by the variable acoustic impedance module 110. The signal changes, the ultrasonic program control head 220 senses The changed ultrasonic reflection signal is detected, converted into a corresponding electrical signal, and then returned to the program controller host 210, thereby realizing the transmission of data from the inside to the outside of the body, as shown in process B in Figure 4.

In the cardiac pacing system, when the implantable cardiac pacemaker 100 sends feedback signals or data to the outside, in order to change the acoustic impedance of the variable acoustic impedance module 110, in one embodiment, the implantable cardiac pacemaker 100 The signal processing module inside can control the variable acoustic impedance film 111 to be powered on or off. The variable acoustic impedance film 111 will exhibit different acoustic impedances when powered on or off. Therefore, the operation of turning on and off the power can also The acoustic impedance of variable acoustic impedance module 110 may be varied.

The communication data transmitted between the implantable cardiac pacemaker 100 and the programming device 200 is described below by way of example.

In one embodiment, when the program control device 200 receives the ultrasonic reflection signal reflected back from the body, when the acoustic impedance of the variable acoustic impedance module 110 in the implantable cardiac pacemaker 100 does not change, the program control device 200 receives the corresponding ultrasonic signal. After reflecting the signal, the corresponding acoustic impedance state is recorded as the first level. When the acoustic impedance of the variable acoustic impedance module 110 changes, the program control device 200 receives the corresponding ultrasonic reflection signal and records the corresponding acoustic impedance state as a second level, which is opposite to the first level. For example, the acoustic impedance state detected from the ultrasonic program control head 220 when the variable acoustic impedance film 111 is not energized can be recorded as 0, and the acoustic impedance state when there is current flowing through it can be recorded as 1.

In one embodiment, when the variable acoustic impedance module 110 does not sense the ultrasonic signal sent by the program-controlled device 200, the processor 121 uses the first level as the level of the ultrasonic signal. When the variable acoustic impedance module 110 senses that the program-controlled device 200 When the ultrasonic signal is sent by 200, the processor 121 uses the second level as the level of the ultrasonic signal, and the second level is opposite to the first level. For example, when the above-mentioned piezoelectric film 112 senses the ultrasonic signal emitted by the ultrasonic program control head 220, the processor 121 obtains the voltage change, which is recorded as 1. When no ultrasonic signal is sensed, there is no voltage or no voltage change, which is recorded as 0. . In the above communication method, the ultrasonic program control head 220 completes the transmission and sensing of ultrasonic signals. The data in the communication process can use pulse signals, and the pulse width can be adjusted according to actual needs. This encoding method only considers whether there are changes in the voltage signal, and does not require high accuracy for the ADC unit 122 and DAC unit 123, which facilitates system design and integration. The present invention is not limited to this. In other embodiments, other communication signal settings may also be used.

The data transmitted between the implantable cardiac pacemaker 100 and the program control device 200 is sent periodically, for example. The data transmitted in each communication cycle is called a communication frame. Each communication frame includes a frame header and frame data, which can be initiated by the external programmer host 210 through the ultrasonic program control head 220. In order to avoid interference or false sensing of the implanted cardiac pacemaker 100, communication can be performed through a set sequence. FIG. 5 is a schematic diagram of a communication frame used for data transmission between the implantable cardiac pacemaker 100 and the program control device 200 according to an embodiment of the present invention. Referring to Figure 5, the data segments are numbered for convenience of explanation. Example No. 1 consists of 5-bit binary data and represents the ultrasonic signal sequence sent by the ultrasonic program control head 220. Number 2 is information that changes the acoustic impedance when the processor 121 receives this sequence. The example consists of 3-bit binary data. After sending data No. 1 and No. 2 and after the ultrasonic program control head 220 senses the response data from the processor 121, No. 3 is sent. No. 3 represents which end of this communication transmits the data. For example, 01 represents that the program-controlled device 200 needs to transmit data. 10 represents the implantable pacemaker 100 transmitting data. When the frame header data is transmitted, the frame data begins to be transmitted. The frame data includes a data segment 4 that represents the length of the entire frame (8 bits in the example), a data segment 5 that represents a checksum, and a data segment 6 that represents the data to be transmitted in the current communication. If there is no data transmission from the implantable pacemaker 100, a reply of 0xFF (frame data length) can be set to end this communication.

The cardiac pacing system is based on single-source ultrasound, and can use the program-controlled device 200 to detect changes in the acoustic impedance of the variable acoustic impedance module 110 in the implantable cardiac pacemaker 100 outside the body. The changes in acoustic impedance can be used as a carrier of information. Passive communication between the implantable cardiac pacemaker 100 and the program-controlled device 200 is realized. At the same time, the variable acoustic impedance module 110 can sense the ultrasonic signal and convert the ultrasonic signal into an electrical signal, so it can also realize communication from outside the body to the body, that is, it can Enables duplex communication. Since ultrasonic signals and ultrasonic reflected signals are used for communication instead of using human tissue as the medium for current conduction, it is not affected by the cardiac cycle. Communication can be initiated by external ultrasonic sending and receiving equipment at any time as needed, with high real-time performance and high communication efficiency. The process has lower requirements on the circuit structure and battery capacity of the implanted end, which facilitates the miniaturization of the implantable pacemaker.

The above-mentioned implantable cardiac pacemaker 100 is, for example, a leadless pacemaker. Since leadless pacemakers do not use wires and have high volume requirements, using the above communication device, compared to the HBC communication method, the communication process is not affected by the cardiac cycle and can be controlled by the programmer host 210 through the ultrasonic program control head at any time. 220 initiated, high real-time performance, and because MEMS processing technology is relatively mature, it can process smaller variable acoustic impedance films 111 and piezoelectric films 112. Using the aforementioned communication method, The accuracy requirements of the ADC unit 122 and the DAC unit 123 are not high, so that the circuit complexity of the package module of the leadless cardiac pacemaker is lower, and the power consumption is also lower.

It should be noted that each embodiment in this specification is described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The same and similar parts between the various embodiments can be referred to each other. .

The above description is only a description of the preferred embodiments of the present invention, and does not limit the scope of rights of the present invention. Any person skilled in the art can use the methods and technical contents disclosed above to improve the present invention without departing from the spirit and scope of the present invention. Possible changes and modifications are made to the technical solution. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention, all belong to the technical solution of the present invention. protected range.

Claims

An implantable cardiac pacemaker, characterized by comprising a variable acoustic impedance module and a signal processing module. The variable acoustic impedance module is used to sense ultrasonic signals, convert the ultrasonic signals into corresponding electrical signals and send them to The signal processing module, 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 ultrasonic signal and the ultrasonic reflection signal are used for the implant Implantable pacemaker communicates with the outside world.
The implantable cardiac pacemaker of claim 1, wherein 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 based on Different signals from the signal processing module are different, and the acoustic impedance of the variable acoustic impedance film generates corresponding ultrasonic reflection signals according to the signals from the signal processing module.
The implantable cardiac pacemaker of claim 2, wherein the variable acoustic impedance module further includes a piezoelectric film electrically connected to the signal processing module, and the piezoelectric film is used to sense the Ultrasonic signals are converted into corresponding electrical signals and sent to the signal processing module.
The implantable cardiac pacemaker according to claim 3, further comprising a shell, the shell being set outside the variable acoustic impedance module and the signal processing module, the variable acoustic impedance module further It includes a backing, the backing is arranged on the inner surface of the housing, and the piezoelectric film and the variable acoustic impedance film are arranged in zones on the backing.
The implantable cardiac pacemaker of claim 4, wherein the variable acoustic impedance module further includes a first sound-absorbing film and a second sound-absorbing film, the first sound-absorbing film being located on the pressure Between the electric film and the variable acoustic impedance film, the second sound absorbing film is located on the side of the variable acoustic impedance film away from the piezoelectric film.
The implantable cardiac pacemaker of claim 5, wherein the piezoelectric film, the variable acoustic impedance film, the first sound-absorbing film and the second sound-absorbing film are annular structures, and their The axes are parallel.
The implantable cardiac pacemaker of claim 6, wherein the width of the first sound-absorbing film is different from the width of the second sound-absorbing film, and both are different from the variable acoustic impedance film. width.
The implantable cardiac pacemaker of claim 2, wherein the signal processing module changes the acoustic impedance of the variable acoustic impedance module by energizing or de-energizing the variable acoustic impedance film.
The implantable cardiac pacemaker of claim 1, wherein the signal processing module includes a processor, an ADC unit and a DAC unit; the ADC unit is used to convert the electrical signal sent by the variable acoustic impedance module. The signal is converted into a digital signal and sent to the processor; the DAC unit is used to convert the signal sent by the processor for changing the acoustic impedance into an analog signal and sends it to the variable acoustic impedance module, so The variable acoustic impedance module adjusts the acoustic impedance according to the analog signal sent by the DAC unit.
The implantable cardiac pacemaker according to claim 1, wherein the implantable cardiac pacemaker is a leadless pacemaker.
A programmable control device, characterized in that it includes a programmable instrument host and an ultrasonic programmable control head; the ultrasonic programmable control head is used to send ultrasonic signals and sense ultrasonic reflection signals; the programmable instrument host emits ultrasonic signals through the ultrasonic programmable control head to The implanted cardiac pacemaker transmits data, and obtains the acoustic impedance state of the implanted cardiac pacemaker through the ultrasonic reflection signal sensed by the ultrasonic programmable control head, and obtains the implanted cardiac pacemaker according to changes in the acoustic impedance state. pacemaker data.
A cardiac pacing system, characterized by comprising the implantable cardiac pacemaker according to any one of claims 1 to 10 and the programmable device according to claim 11.