CN111657928B

CN111657928B - Implanted medical equipment for recognizing cardiac events by aid of blood flow parameters and electrocardiosignals

Info

Publication number: CN111657928B
Application number: CN202010700971.2A
Authority: CN
Inventors: 李娜
Original assignee: Suzhou Wushuang Medical Equipment Co ltd
Current assignee: Suzhou Wushuang Medical Equipment Co ltd
Priority date: 2020-07-20
Filing date: 2020-07-20
Publication date: 2022-09-09
Anticipated expiration: 2040-07-20
Also published as: CN111657928A

Abstract

The invention discloses implanted medical equipment for recognizing a cardiac event by using blood flow parameters and electrocardiosignals. The implanted medical equipment identifies cardiac events through blood flow velocity, blood flow pressure and R peak value on the basis of updating ventricular fibrillation count value through the electrocardiosignal. A sensing circuit for sensing the electrocardiosignal, the blood flow velocity and the blood flow pressure; the memory circuit is used for storing an identification program for identifying ventricular fibrillation through electrocardiosignals, blood flow velocity and blood flow pressure; execution circuitry configured to execute a ventricular fibrillation event identification procedure. Cardiac events of the present invention include ventricular fibrillation, rapid ventricular velocity, and ventricular velocity. The efficiency of identification of cardiac events is improved.

Description

Implanted medical equipment for recognizing cardiac events by aid of blood flow parameters and electrocardiosignals

Technical Field

The invention relates to the field of medical treatment, in particular to implanted medical equipment for recognizing a cardiac event by using blood flow parameters and electrocardiosignals. More particularly, the invention relates to an implanted medical device for assisting in identifying ventricular fibrillation and post-ventricular fibrillation shock treatment events by electrocardiosignals, blood flow velocity and blood flow pressure.

Background

Implantable cardioverter-defibrillators (ICDs), Implantable Cardiac Monitors (ICMs), cardiac pacemakers (cardiac pacemakers) or leadless implanted cardiac pacemakers and Subcutaneous Implanted Cardiac Defibrillators (SICDs) are important medical devices for clinically treating persistent or fatal ventricular arrhythmias.

Implantable cardioverter-defibrillators (ICDs) are an important clinical therapy for persistent or fatal ventricular arrhythmias, and have supportive, anti-tachycardia pacing, low-energy cardioversion, and high-energy defibrillation effects.

Currently, sensing of ventricular rate has become a state of the art technique, either by implanting a device carrying a sensing member inside the heart or by placing it outside the patient's body. Sensing signals inside the heart chambers includes heart sounds, rate, amplitude, frequency, period, etc.

Heart disease is the disease with the highest prevalence and mortality worldwide, and the vast majority of patients with cardiovascular disease die from cardiac arrest. Sudden cardiac arrest refers to sudden cardiac arrest, resulting in severe ischemia and hypoxia of vital organs (such as brain) and termination of life. The most effective treatment method of cardiac arrest is defibrillation shock, and for cardiac arrest patients, effective defibrillation shock within 3-5 minutes is the only pre-hospital emergency treatment method effective in reducing the mortality of the patients.

ICDs can identify a patient's tachyventricular arrhythmia within seconds and then automatically discharge defibrillation, thus significantly avoiding the incidence of sudden death from malignant ventricular arrhythmias and avoiding untimely treatment.

Heart disease is a general term for all heart diseases, but in clinical procedures, different treatments are required for the same kind of heart disease. The treatment of heart diseases needs to be specifically determined by combining the severity of the diseases, the onset positions and the like. In order to accurately identify the type of heart disease suffered by a patient and achieve better treatment effect, it is necessary to more finely classify the type of heart disease clinically, and the purpose is usually achieved in the process of diagnosing the heart disease.

Currently, a typical identification method for heart diseases uses an electrocardiographic signal as a parameter to identify whether heart diseases exist in the heart, and performs treatment according to a judgment result. However, there is no method for assisting in identifying cardiac events by blood flow parameters (blood flow rate or blood flow pressure) based on the identification of ventricular fibrillation count values by cardiac electrical signals. The invention discloses implanted medical equipment for identifying ventricular fibrillation and a treatment event after ventricular fibrillation by means of electrocardiosignals, blood flow velocity and blood flow pressure, and the identification of the ventricular fibrillation and the electrode treatment efficiency are improved.

Disclosure of Invention

Implantable medical devices that combine identification of ventricular fibrillation, rapid ventricular velocity, ventricular velocity events, and post-identification shocking therapy of ventricular fibrillation are described. More particularly, the invention relates to an implanted medical device for assisting electrocardiosignal identification of ventricular fibrillation and post-ventricular fibrillation electric shock treatment events through blood flow parameters. In some examples, triggering of these measurements may be done automatically (e.g., without a triggering input initiated from an external source, such as based on a request initiated from the patient or from an external device by a physician), and based at least in part on monitoring one or more physiological parameters associated with the patient, diagnosing the type of cardiac disease based on threshold values of the physiological parameters.

The invention provides an implanted medical system for recognizing an electric shock treatment event after ventricular fibrillation by using blood flow parameters to assist electrocardiosignals. The implanted medical system includes: communication circuitry configured to communicate with an external computing device, sensing circuitry configured to sense a patient-based cardiac electrical signal, a blood flow rate, and a blood flow pressure, and processing circuitry. The processing circuitry may be configured to: determining a series of consecutive cardiac disorder threshold ranges based on the sensed cardiac signal; and diagnosing the type of cardiac disorder based on each of the different types of cardiac disorders threshold values. The processing circuitry may be further configured to: detecting a suspended episode of the cardiac disorder of the patient based on the sensed cardiac signal, and controlling the communication circuitry to transmit an indication of the detected suspended episode of the cardiac disorder to an external computing device.

Ventricular fibrillation identification in the present invention includes: ventricular fibrillation is identified by the assistance of electrocardiosignals, blood flow velocity and blood flow pressure. The method for judging whether the ventricular fibrillation counting condition is met through the electrocardiosignals comprises two methods: one method is to count the ventricular fibrillation directly and combine the counting with a backtracking window to finish the preliminary identification of the ventricular fibrillation; the other is the preliminary identification by the combined counting of ventricular fibrillation and backtracking window. Ventricular fibrillation is identified by the assistance of electrocardiosignals, blood flow velocity and blood flow pressure. The accuracy of ventricular fibrillation event identification is improved, and the method has great significance for identification of ventricular fibrillation of cardiac events.

The invention discloses implanted medical equipment for recognizing ventricular fibrillation events by blood flow parameters and electrocardiosignals, which comprises:

an implantable medical device for recognizing ventricular fibrillation events by using blood flow parameters to assist electrocardiosignals, the implantable medical device comprising:

a sensing circuit for sensing the electrocardiosignal, the blood flow velocity and the blood flow pressure;

the memory circuit is used for storing an identification program for identifying ventricular fibrillation through electrocardiosignals, blood flow velocity and blood flow pressure;

an execution circuit configured to execute a procedure for identifying a ventricular fibrillation event;

the identification program for identifying the ventricular fibrillation through the electrocardiosignals, the blood flow velocity and the blood flow pressure comprises the following steps of:

obtaining a current real-time blood flow velocity or blood pressure peak value and an R peak value;

updating the blood flow velocity or blood flow pressure peak value and the R peak value sequence in the shift register;

calculating the ratio of the blood flow velocity or the blood flow pressure in the shift register to the R peak as a standard value P;

calculating an average value s and upper and lower thresholds of the ratio P in the time period T, wherein the upper and lower thresholds are the average value +/-3 multiplied by a standard value;

judging whether the electrocardiosignals meet the ventricular fibrillation counting condition or not, and if so, starting a backtracking window;

counting the number k of the ratio P of the blood flow velocity or the blood flow pressure to the R peak in the backtracking window within the range of the threshold value;

if the value k reaches a first threshold value h, identifying a ventricular fibrillation event;

and if the electrocardiosignal does not meet the ventricular fibrillation counting condition or the numerical value k does not reach the threshold value h, returning to update the real-time blood flow velocity or the blood pressure peak value and the R peak value.

The step of judging whether the electrocardiosignal meets the ventricular fibrillation counting condition comprises the following steps:

acquiring a current real-time heart rate value;

continuously updating the real-time heart rate data sequence by the current real-time heart rate value;

if the real-time heart rate data sequence is larger than the rapid ventricular rate threshold value, adding 1 to the ventricular fibrillation count value;

updating the ventricular fibrillation count value, and starting a backtracking window when the ventricular fibrillation count value reaches a threshold t 1;

if the heart rate value located in the ventricular fibrillation area exists in the backtracking window, identifying the ventricular fibrillation area; otherwise, a fast chamber speed is identified.

acquiring a current real-time heart rate value;

updating a ventricular fibrillation count value, and updating a combined count when the ventricular fibrillation count value reaches a threshold t1, wherein the combined count is ventricular fibrillation count + ventricular speed count;

if the combined count reaches t2, judging whether a heart rate value in the ventricular fibrillation area exists in a backtracking window;

if so, identifying ventricular fibrillation; otherwise, continuously judging whether the heart rate value positioned in the rapid chamber velocity area exists in the backtracking window;

if so, identifying the rapid chamber speed; otherwise, the chamber velocity is identified.

The method for updating the ventricular fibrillation count value comprises the following steps:

updating the real-time heart rate data sequence;

and counting the number of rapid ventricular rate ranges in the real-time heart rate data sequence as ventricular fibrillation counts.

The ventricular fibrillation has the characteristic of high morbidity rate, and when the ventricular fibrillation occurs to a human body, if the detection is not timely, sudden death of a patient is easily caused, so that when the ventricular fibrillation occurs, corresponding treatment is urgently needed. Currently, treatment of ventricular fibrillation is mainly performed by electric shock. Because the ventricular fibrillation discharges high voltage during shock therapy, which causes great damage to the human body, a very accurate cardiac shock event identification method is needed to minimize damage to the heart and identify ventricular fibrillation events.

The shock event of the present invention is used to treat ventricular fibrillation by delivering pulses that are induced by the event of ventricular fibrillation, and is therefore referred to as a post-ventricular fibrillation shock treatment event.

The invention discloses implanted medical equipment for recognizing an electric shock treatment event after ventricular fibrillation by using blood flow parameters to assist electrocardio signals, wherein the recognition step of the ventricular fibrillation event comprises the recognition step of the ventricular fibrillation event, and if the cardiac event is recognized as ventricular fibrillation, electric shock treatment is carried out.

The medical system judges whether the electrocardiosignals meet the ventricular fibrillation counting condition through medical equipment, and the judgment step of the ventricular fibrillation counting condition comprises the following steps:

acquiring a current real-time heart rate value;

if the joint count reaches t2, judging whether a heart rate value in the ventricular fibrillation region exists in the backtracking window;

The implanted medical device performs treatment by delivering pulses after identification of an electrical shock event.

The ventricular fibrillation identification method of the present invention is programmed as an algorithm in the form of a programming language into a computer chip that is placed in an implanted medical device that is part of an implanted medical system.

The invention discloses an implanted medical system for recognizing post-ventricular fibrillation electric shock treatment events by aid of blood flow parameters and electrocardiosignals, which comprises the implanted medical equipment as claimed in claims 5 to 8, and further comprises:

the pulse generator is composed of a device shell and an internal circuit, and the internal circuit is provided with a sensing circuit, a storage circuit and an execution circuit;

the electrode lead is connected with the pulse generator and the myocardial tissue and transmits the electrocardiosignal to the pulse generator;

and the program control instrument is used for carrying out parameter display, parameter setting and parameter regulation and control on the pulse generator.

The electrode lead of the implanted medical system may be a single lead, a double lead, a triple lead, or a quadruple lead.

The necessary information for establishing the far-field communication connection between the pulse generator and the program-controlled instrument of the implanted medical system comprises a communication channel, a communication mode, a communication frequency, a communication modulation mode and an encryption key.

Drawings

Fig. 1 is a schematic diagram of the external structure of the implanted medical device and the relative positions of the components in the human body when the implanted medical device is implanted in the human body.

Fig. 2 is a schematic view of a flow structure for assisting in identifying ventricular fibrillation by electrocardiosignals, blood flow velocity and blood flow pressure.

Fig. 3 is a schematic view of a flow structure of assisting in identifying an event of electric shock therapy after ventricular fibrillation by using an electrocardiosignal, a blood flow velocity and a blood flow pressure.

Fig. 4 is a schematic diagram of a logic structure of a real-time data sequence of heart rate, blood flow velocity or blood flow pressure.

Fig. 5 is a schematic diagram of a first flowchart for identifying ventricular fibrillation count conditions through electrocardiosignals.

Fig. 6 is a schematic diagram of a second flow structure for identifying ventricular fibrillation count conditions through electrocardiosignals.

Fig. 7 is a schematic diagram of the flow chart of updating the ventricular fibrillation count value in step 606 of fig. 6.

Detailed Description

Implantable medical devices (implants) are ubiquitous to provide diagnostic or therapeutic capabilities. The method for comprehensively identifying the ventricular fibrillation and the electric shock can be applied to implantable cardioverter defibrillators, subcutaneous implantable cardiac defibrillators, implantable cardiac pacemakers, leadless implantable cardiac pacemakers, various tissues, organs, nerve stimulators or sensors and other implantable medical equipment.

The invention can identify ventricular fibrillation and an electric shock treatment event after the ventricular fibrillation by the aid of the blood flow parameters. In some examples, triggering of these measurements may be done automatically (e.g., without a trigger input initiated from an external source, such as based on a request initiated from the patient or from an external device by a physician), and triggering the measurement of ventricular rate may occur within certain numerical ranges based at least in part on monitoring one or more physiological parameters associated with the patient.

A system of an Implantable Medical Device (IMD) of the present invention may include: communication circuitry configured to communicate with an external computing device, sensing circuitry configured to sense changes in cardiac electrical signals, blood flow pressure, and blood flow velocity of the patient, and processing circuitry. The processing circuitry may be configured to: determining a series of consecutive cardiac disorder threshold ranges based on the sensed one or more cardiac parameters; and diagnosing a type of the cardiac disorder based on each of the different types of cardiac disorders threshold values. The processing circuitry may be further configured to: detecting a onset of a pause in the patient's cardiac disorder based on the sensed cardiac signal parameter, and controlling the communication circuitry to transmit an indication of the detected onset of the pause in the cardiac disorder to an external computing device.

When the implantable medical system is an implantable cardioverter-defibrillator (ICD), the implantable medical system comprises: the pulse generator is composed of a device shell and an internal circuit, wherein the internal circuit is provided with a sensing circuit, a storage circuit and an execution circuit; the electrode lead is connected with the pulse generator and the myocardial tissue and transmits the electrocardiosignal to the pulse generator; and the program controller is used for displaying, setting and controlling parameters of the pulse generator. When the pulse generator and the electrode lead are implanted into a patient, the pulse generator is implanted into subcutaneous tissue, and the electrode lead passes through the superior vena cava to enter the heart and be connected with myocardial tissue. The pulse generator, also referred to as the body of the implanted medical system, is comprised of a device housing, a head structure, and a battery, capacitor, circuit, antenna, substrate, etc. inside the device housing. The material of the pulse generator must be a biocompatible material, i.e. the material of the pulse generator itself needs to be compatible with the human body after being implanted into the human body, and a biocompatible titanium shell, a permeable biocompatible material or other impermeable biocompatible materials are generally selected. The program control instrument is placed outside the body, can remotely measure the pulse generator, has a parameter display function, can display sensed electrocardio parameters on a functional interface in an image or digital mode, and can also set and regulate related parameters through the program control instrument.

The ventricular fibrillation has the characteristic of high morbidity rate, the morbidity rate is dozens of minutes or even minutes, and when the ventricular fibrillation occurs to a human body, if the detection or treatment is not timely, sudden death of a patient is easily caused. Therefore, when ventricular fibrillation occurs, timely treatment is critical. Currently, treatment of ventricular fibrillation is primarily by electric shock. Because the ventricular fibrillation discharges high voltage during shock therapy and has great damage to a human body, a set of very accurate cardiac shock event identification method is needed in order to minimize damage to the heart or other parts and identify ventricular fibrillation events without omission.

The implantable cardiac defibrillation system can sense ventricular tachycardia or ventricular fibrillation, the tachycardia sensing frequency is set according to the clinical ventricular tachycardia frequency, and when the ventricular tachycardia frequency is higher than the sensing frequency, the pulse generator is triggered to discharge, so that electric shock energy is released to the heart, and a treatment function is implemented. The pulse generator contains a battery as an energy source, an electrolytic capacitor to store energy, and various electronic circuits. The shell of the pulse generator is made of titanium, the connector of the pulse generator is made of epoxy polymer resin, and the connector is provided with 3-4 jacks connected with sensing and defibrillation electrode leads. The electrode lead is connected to the heart through the superior vena cava, and electrocardiosignals are monitored through the electrode lead to identify whether ventricular tachycardia/ventricular fibrillation occurs or not and release electric energy for cardioversion or defibrillation.

The invention discloses an implanted medical system for recognizing an electric shock treatment event after ventricular fibrillation by using blood flow parameters and electrocardiosignals, wherein the implanted medical system is implanted with medical equipment and also comprises: the pulse generator is composed of a device shell and an internal circuit, wherein the internal circuit is provided with a sensing circuit, a storage circuit and an execution circuit; the electrode lead is connected with the pulse generator and the myocardial tissue and transmits the electrocardiosignal to the pulse generator; and the program control instrument is used for carrying out parameter display, parameter setting and parameter regulation and control on the pulse generator. The electrode lead of the implanted medical system may be a single lead, a double lead, a triple lead, or a quadruple lead. The necessary information for establishing the far-field communication connection between the pulse generator and the program-controlled instrument of the implanted medical system comprises a communication channel, a communication mode, a communication frequency, a communication modulation mode and an encryption key. The electrode lead of the implanted medical system is connected to the head assembly of the medical device through a feedthrough. The control module initializes far-field communication module parameters using the parameter settings.

Fig. 1 is a structural schematic diagram of an appearance structure of an implanted medical device and relative positions of components of the implanted medical device in a human body when the implanted medical device is implanted in the human body. Using ICD 116 as an example, the specific operation of an implantable medical device when implanted in a region of the heart 114 of human 100 is described. ICD 116 is comprised of housing assembly 118, head assembly 102 and lead 104. The device shell is internally provided with a main circuit board, a power supply, a capacitor, a transformer, a feed-through assembly, a feed-through buffer assembly and an antenna. The implantable medical device has four functions 120: a processor function 122, a memory function 124, a telemetry function 126, and an interface function 128. Typically, ICDs are also capable of performing user display functions by interfacing with an in vitro programmer or remote follow-up. The processor function 122 refers to the ICD being able to autonomously sense cardiac electrical signals or physiological parameters of the human body 100 through the electrodes, autonomously perform diagnosis, and issue treatment commands. In the case of an ICM, the processor function means that it is capable of issuing diagnostic commands based on the diagnostic signal parameters, excluding treatment commands. The memory function 124 refers to a function of the ICD storing the cardiac electrical signals for a period of time and searching or reading the cardiac electrical signal parameters recorded in the period of time at a later time. The feedthrough assembly of the implantable medical device encapsulates the antenna feedthrough and the lead feedthrough inside. The feed-through assembly comprises two parts of a lead feed-through and an antenna feed-through. The feed-through assembly is provided with a high-voltage part and a low-voltage part, wherein the high-voltage part is a lead feed-through, and the high-voltage part is connected with the lead; the low voltage part is an antenna feed-through, which is connected to the antenna. The main circuit board inside the device housing is usually implemented by a chip through program coding. The ICD function can be achieved through two modes, one mode is that the ICD body can be regulated and controlled independently, and manual triggering and control are not needed. Another is telemetry 126 and ICD control via an external programming device, typically a programmer, patient assistant, or other device capable of commanding it or sensing its internal signals. Telemetry 126 between the ICD and the external programming device may be one or more of wired communication, bluetooth, WIFI, LTE, CDMA, or other wireless communication networks. While the ICD needs to have interface functionality 128, for example, the ICD needs to implement far-field telemetry monitoring and control via a bluetooth interface, a wireless interface, or a wired interface, the implantable medical device has at least one of these interface functionalities. The ICD lead 104 shown in FIG. 1 is a single lead, and may be a double lead, a triple lead, or a quadruple lead during clinical use, with the basic structure of different gauge leads being similar to that of the single lead 104. The lead 104 is comprised of a coil 108, a pacing sensing electrode ring end 110, and a pacing sensing tip 112. Lead 104 is connected to ICD device body 116 through head assembly 102. The lead 104 is threaded through the superior vena cava 132 and the atrium 130 of the body 100 and can be implanted within the ventricle 106. Coil 108 is capable of defibrillation therapy of the diagnosed ventricular fibrillation event by delivering a pulse. During treatment, the device body shell 118 itself serves as an electrode, and a voltage difference is formed between the device body shell and the coil 108, so that the ventricle is electrically stimulated to achieve the treatment purpose. The pacing sensing electrode ring terminal 110 is capable of sensing cardiac electrical signals and physiological parameters within the heart 114. The pacing sensing electrode ring end 110 is internally packaged with a pacing sensing tip 112, and the pacing sensing tip 112 is a spiral coil. The pacing sensing tip 112 is rotated in the lead before use, and when implanted in the heart of a human body, the pacing sensing tip 112 is rotated out of the lead from one end of the lead and is connected and fixed with myocardial tissue in the heart. The electrode lead needs to be coated by insulating materials such as silica gel, polyurethane or epoxy resin.

The ventricular fibrillation identification is assisted by the electrocardiosignal, the blood flow velocity and the blood flow pressure to identify the ventricular fibrillation on the basis of meeting the ventricular fibrillation counting value. Two methods for judging whether the ventricular fibrillation counting condition is met through the electrocardiosignals are available: one method is to count the ventricular fibrillation directly and combine the counting with a backtracking window to finish the preliminary identification of the ventricular fibrillation; the other is the preliminary identification by the combined counting of ventricular fibrillation and backtracking window. The method for identifying ventricular fibrillation in fig. 2 and 3 is performed based on the judgment of the ventricular fibrillation counting condition through an electrocardiosignal in fig. 5 or 6, and obviously, the judgment method of the ventricular fibrillation counting condition includes, but is not limited to, the method shown in fig. 5 or 6, other existing ventricular fibrillation identification methods, and ventricular fibrillation identification methods by means of other physiological parameters, which are well known to those skilled in the art. The ventricular fibrillation is identified by the assistance of the electrocardiosignals, the blood flow velocity and the blood flow pressure, so that the accuracy of identifying the ventricular fibrillation event is improved, and the ventricular fibrillation event identification method has great significance for identifying the ventricular fibrillation event of the cardiac event.

The updating of the electrocardiosignal sequence is carried out by a shift register. And the shift register shifts once every time the electrocardiosignal is updated. The data recorded by the shift register can be kept in the storage circuit within a certain time period or a certain heartbeat frequency range, the initial duration of the time period can be designed and written into a program through a programming language during circuit design, and when a product is implanted in the later period, the adjustment and the appropriate modification of experts can be specifically carried out according to various measured physical parameters of a patient.

The preconditions for the occurrence of ventricular fibrillation events according to the invention as shown in fig. 2 and the preconditions for the occurrence of electrode treatment events after ventricular fibrillation as described in fig. 3. In theory, a ventricular shock event occurs after the flow velocity of blood flow assists in identifying a ventricular fibrillation event, and when the implanted medical system identifies a ventricular fibrillation event, a ventricular shock therapy command is executed. In the flow chart of FIG. 3, a cardiac shock event is not labeled as a "ventricular fibrillation" event until the "shock" event occurs at step 318, but in actual theory, a ventricular shock event is triggered by a ventricular fibrillation event.

Fig. 2 is a schematic view of a flow structure for assisting in identifying ventricular fibrillation events through electrocardiosignals, blood flow velocity and blood flow pressure. Step 202, obtaining the current real-time electrocardiosignals, the blood flow velocity and the blood pressure peak value. Step 204 updates the center electrical signal of the shift register, the blood flow velocity and the blood flow pressure peak value sequence. Step 206 calculates the ratio of the current real-time blood flow velocity or blood pressure to the R peak, which is denoted as P, i.e. P is the real-time blood flow velocity peak or blood pressure peak/R peak. Step 208 calculates the average s and upper and lower thresholds of the ratio P in a time period T, which is an integer number of heartbeat cycles, for example: 24 heart cycle periods. The ratio P of the blood flow velocity or the blood flow pressure to the R peak value is equal to the number of heart cycle, for example, the ratio P is 24 values at 24 jump. The mean value s is equal to the mean value of the ratio P of the blood flow velocity or the blood pressure to the R peak value over the time period T, for example, the mean value of 24P values. The real-time blood flow velocity value, the blood flow pressure value and the R peak value are continuously updated through a shift register, and updated data are stored in a storage circuit. Obviously, the blood flow velocity value, the blood flow pressure value, and the R peak value sequence length stored in the storage circuit do not exceed the total sequence length of the shift register 400 in fig. 4. The upper and lower thresholds are two values, i.e. an upper limit and a lower limit, the upper limit is the average value s +3 × standard deviation, the lower limit is the average value s-3 × standard deviation, if the ratio P sequences of the blood flow velocity or blood pressure to the R peak value in the time period T are n, and the n sequences are respectively expressed as: p1, P2, P3, P4, P5,.. times, Pn, the arithmetic square root of variance is sqrt (((P1-x) ^2+ (P2-x) ^2+. 9.. times. (Pn-x) ^ 2)/(n-1)). Step 210 judges whether the electrocardiosignal meets the ventricular fibrillation counting condition, and if the electrocardiosignal meets the ventricular fibrillation counting condition, step 212 starts a backtracking window. Step 214 counts the number of the ratio P of the blood flow velocity or the blood pressure peak value outside the threshold range (from the average value s-3 × the standard deviation to the average value s +3 × the standard deviation) in the backtracking window, that is, in the backtracking window, P satisfies the condition: p is less than or equal to the average value s-3 multiplied by the standard deviation, or the number of P values when P is more than or equal to the average value s +3 multiplied by the standard deviation is marked as k. Step 216 determines whether the value k reaches a threshold value h, for example: 3/5, at this time h is 5 and P is 3, i.e. 3 out of 5 heartbeats. Step 218 identifies a ventricular fibrillation event. And if the electrocardiosignal does not meet the ventricular fibrillation counting condition in the step 210 or the numerical value k in the step 216 does not reach the threshold value h, returning to the step and starting to obtain the current real-time blood pressure peak value, the blood flow velocity peak value and the R peak value.

The heart parameter measured by the invention is one of the electrocardiosignal and the blood flow velocity or the blood flow pressure, namely the electrocardiosignal and the blood flow pressure value can be measured simultaneously, the electrocardiosignal and the blood flow velocity value can be measured simultaneously, and the blood flow velocity and the blood flow pressure do not have priority relation logically.

The implanted medical system of the invention, including an Implanted Cardioverter Defibrillator (ICD), an implanted heart monitor (ICM), a cardiac pacemaker (cardiac pacemaker) or leadless implanted cardiac pacemaker and a Subcutaneous Implanted Cardiac Defibrillator (SICD), is an important medical device for clinically treating persistent or fatal ventricular arrhythmias. The implanted medical system comprises an acquisition module, and is used for acquiring pressure data, respiration data, apical pulsation data, electrocardiogram signals, blood flow velocity, blood flow pressure and other parameters of the defibrillation electrode plates. When the defibrillation electrode slice does not fall off, respiration does not exist, the apex of the heart does not beat and ventricular fibrillation occurs, sending a defibrillation instruction to the defibrillation module and sending a starting instruction to the prompt module; and the defibrillation module is used for receiving a command of manually cancelling defibrillation, and if the command of manually cancelling defibrillation is not received within a set time after the defibrillation command is received, defibrillation is executed.

Fig. 3 is a schematic view of a flow structure of an electrode treatment event after ventricular fibrillation is identified with assistance of an electrocardiosignal, a blood flow velocity and a blood flow pressure. Step 302 obtains current real-time electrocardiosignals, blood flow velocity and blood flow pressure peak values. Step 304 updates the shift register center electrical signal, blood flow velocity, and blood flow pressure peak sequence. Step 306 calculates the ratio of the current real-time blood flow rate or blood pressure to the R peak, which is denoted as P, i.e. P is the real-time blood flow rate peak or blood pressure peak/R peak. Step 308 calculates the average value s and the upper and lower thresholds of the ratio P in a time period T, where the time period T is an integer number of heartbeat cycles, for example: 24 heart cycle periods. The ratio P of the blood flow velocity or the blood flow pressure to the R peak value is equal to the number of heart cycle, for example, the ratio P is 24 values at 24 jump. The mean value s is equal to the mean value of the ratio P of the blood flow velocity or the blood pressure to the R peak value over the time period T, for example, the mean value of 24P values. The real-time blood flow velocity value, the blood flow pressure value and the R peak value are continuously updated through a shift register, and updated data are stored in a storage circuit. Obviously, the blood flow velocity value, the blood flow pressure value, and the R peak value sequence length stored in the storage circuit do not exceed the total sequence length of the shift register 400 in fig. 4. The upper and lower thresholds are two values, i.e., an upper limit and a lower limit, the upper limit is the average value s +3 × standard deviation, the lower limit is the average value s-3 × standard deviation, and the standard deviation is the arithmetic square root of the variance sqrt (((P1-x) ^2+ (P2-x) ^2+ -.. 9. -.) (n-1)). Step 310 judges whether the electrocardiosignal meets the ventricular fibrillation counting condition, and if the electrocardiosignal meets the ventricular fibrillation counting condition, step 312 starts a backtracking window. Step 314 counts the number of the ratio P of the blood flow velocity or the blood pressure peak value outside the threshold range (from the average value s-3 × the standard deviation to the average value s +3 × the standard deviation) in the backtracking window, that is, in the backtracking window, P satisfies the condition: the number of P values when P is more than or equal to the average value s-3 multiplied by the standard deviation or P is more than or equal to the average value s +3 multiplied by the standard deviation is marked as k. Step 316 determines whether the value k reaches a threshold h, for example: 3/5, at this time h is 5 and P is 3, i.e. 3 out of 5 heartbeats are in the threshold range. Step 318 shock. And if the electrocardiosignals in the step 310 do not meet the ventricular fibrillation counting condition or the numerical value k in the step 316 does not reach the threshold value h, returning to the step and initially obtaining the current real-time blood pressure peak value, the blood flow velocity peak value and the R peak value.

Fig. 5 and fig. 6 are schematic diagrams of a flow structure for identifying ventricular fibrillation counting conditions through electrocardiosignals, and the difference between the flow method shown in fig. 5 and the flow method shown in fig. 6 is as follows: FIG. 5 is a diagram of direct ventricular fibrillation overlay counting combined with a backtracking window to determine ventricular fibrillation counting conditions; FIG. 6 combines joint counting with backtracking window to make a determination of ventricular fibrillation count conditions. FIG. 6 the combined counting method is based on ventricular fibrillation counts and rapid ventricular velocity counts. The flow method of fig. 2 or fig. 3 of the present invention includes a step of identifying a condition of ventricular fibrillation count, which may be, but is not limited to, the method of ventricular fibrillation count of fig. 5 or fig. 6.

Fig. 5 is a schematic diagram of a first flow structure for identifying ventricular fibrillation count conditions through electrocardiosignals. Step 502 obtains a current real-time heart rate value through sensing the parameters of the electrocardiosignal, step 504 continuously updates a real-time heart rate sequence, the real-time heart rate sequence is stored in a shift register, and the shift register executes one-time shift after the real-time heart rate is obtained. Step 506 compares the sensed real-time heart rate value with a fast ventricular rate threshold value, when the real-time heart rate value is greater than the fast ventricular rate threshold value, step 508 adds 1 to the ventricular fibrillation count value based on the original ventricular fibrillation value, step 510 updates the ventricular fibrillation count value through the ventricular fibrillation counter, step 512 compares the ventricular fibrillation count value with a threshold value t1, when the ventricular fibrillation count value is accumulated to reach t1, step 514 starts a backtracking window, the ventricular fibrillation count value t1 is set to be 18, and it is obvious that a person skilled in the art can adjust the threshold value t1 according to technical knowledge grasped by the person. Step 516, judging whether a real-time heart rate in the ventricular fibrillation region exists in the backtracking window, and if the real-time heart rate in the ventricular fibrillation region exists in the backtracking window, identifying the real-time heart rate as ventricular fibrillation in step 520; otherwise (no real-time heart rate values located in the ventricular fibrillation region exist in the backtracking window), step 518 identifies a fast ventricular rate. The chamber speed threshold is preferably one of 90 to 200bpm, for example 150 bpm. The fast ventricular rate threshold value ranges from 140 to 250bpm, and the ventricular fibrillation threshold value is larger than 250 bpm. Assuming that the slow ventricular speed threshold value is 150bpm, the fast ventricular speed threshold value is 200bpm, and the ventricular fibrillation threshold value is 250 bpm; then the real-time heart rate is considered as a therapy-free heart rate if x (n) <150bpm, as being in the ventricular rate region if 150 ≦ x (n) <200bpm, as being in the ventricular rate region if 200 ≦ x (n) <250bpm, and as being in the ventricular fibrillation region if x (n) > 250. The fast-room speed threshold may be different for different patients. The specific threshold values require the physician to set in the specific parameters of the programmer according to the patient's condition. The counting mode of the backtracking window is various, and the counting mode can be according to the heartbeat number, the time or other counting standards, when the counting mode is according to the heartbeat number, the real-time heartbeat number included in the backtracking window is a positive integer, for example, 10 hops, and it is obvious that a person skilled in the art can adjust the heartbeat number according to the technical knowledge grasped by the person.

Fig. 6 is a schematic diagram of a second flow structure for identifying ventricular fibrillation count conditions through electrocardiosignals. Step 602, obtaining a current real-time heart rate value through sensing a parameter of a electrocardiosignal, and step 604, continuously updating a real-time heart rate sequence, wherein the real-time heart rate sequence is stored in a shift register, and the shift register performs one-time shift after the real-time heart rate is obtained. Step 606 updates the ventricular fibrillation count value via the ventricular fibrillation counter. The method for updating the ventricular fibrillation count value comprises the following steps: when the real-time heart rate is larger than the fast ventricular rate region, the ventricular fibrillation counting value is increased by 1, and when the ventricular fibrillation counting value is smaller than t1, the ventricular fibrillation counting value is continuously overlapped and counted. Step 608 compares the ventricular fibrillation count value with a threshold t1, and when the ventricular fibrillation count value reaches a threshold t1, step 610 updates the joint count value by a joint counter, which is calculated by: the joint count is the algebraic sum of the ventricular rate count and the ventricular fibrillation count. The counting method of the chamber speed comprises the following steps: the number of the real-time heart rate sequences which is larger than the chamber speed threshold value. The heart rate range of the room speed threshold value is 90-200 bpm; the ventricular fibrillation count method is shown in figure 5. Step 612 compares the joint count with a threshold t2, when the joint count reaches t2, step 614 starts a backtracking window, and determines whether a real-time heart rate value (e.g., a heart rate value greater than 250 bpm) in the ventricular fibrillation region exists in the backtracking window, if so, step 616 identifies ventricular fibrillation; otherwise, step 618 continues to determine if there are real-time heart rate values in the fast chamber rate region in the backtracking window, if so, then step 620 identifies fast chamber rate, otherwise step 622 identifies chamber rate. Cardiac events identified by the present invention are, but not limited to, ventricular tachycardia, rapid ventricular tachycardia, and ventricular fibrillation. The ventricular fibrillation and ventricular speed counts are counted independently using the same real-time heart rate x (n) data, with the values of ventricular fibrillation and ventricular speed counts being stored in different variable values, respectively.

The heart pumps have a periodicity that results in the following variable periodicity phenomena: such as the cyclic changes of the intracardiac pressure and the intravascular pressure, the volumes of the atria and the ventricles, the opening and closing of the intracardiac valves, the blood flow velocity and the like. These changes drive the blood flow in a certain direction within the blood vessel. The heart cycle is accompanied by the periodic changes of electrocardio, heart sound, arteriovenous pulsation, blood flow velocity, blood flow pressure and the like. They reflect the functional state of the heart. The abnormalities of electrocardio, heart sound and pulse, blood flow velocity and blood flow pressure are important bases for diagnosing cardiovascular diseases. The invention identifies ventricular fibrillation and cardiac shock events according to electrocardio signals, blood flow velocity and blood flow pressure.

When the heart of a human body is in diastole, the internal pressure is reduced, the vena cava blood flows back into the heart, and when the heart is in systole, the internal pressure is increased, and the blood is pumped to the artery. Each contraction and relaxation of the heart constitutes a cardiac cycle. The first of a cardiac cycle is a two-atrial contraction, in which the right atrium contracts slightly before the left atrium. The atria begin to dilate and the two ventricles contract, while the left ventricle contracts slightly before the right ventricle. In the late phase of ventricular relaxation the atria start to contract again.

The updating method of the blood flow velocity peak value comprises the following steps: the blood flow velocity at each location in the heart chamber is different if a flow rate sensor is placed in the middle of the right ventricle. During the rapid filling period of the ventricles, blood in the atria is rapidly sucked into the ventricles, the flow rate is rapidly increased, then the blood pressure in the ventricles is continuously increased, the blood pressure in the ventricles enters the slow filling period, the flow rate is reduced, the ventricles are in the end diastole, the atria contract, and the blood in the atria is further discharged into the ventricles. Then the blood enters a ventricle to perform isovolumetric contraction, the pressure in the ventricle rises, when the pressure in the ventricle exceeds the atrium, the tricuspid valve is closed, the pressure in the right ventricle is still lower than the pressure of the pulmonary artery, the pulmonary valve is not opened, the blood flow rate is almost reduced to zero, when the blood pressure continues to rise to exceed the pressure of the pulmonary artery, the pulmonary valve is opened, the rapid ejection period of the ventricle is started, the flow rate rises rapidly again, the blood flow direction is opposite to the previous direction, a reverse peak is formed, after the rapid ejection period, the myocardial contraction force is weakened, the slow ejection period is started, the volume of the ventricle is reduced to the minimum, the ejection is stopped, the ventricular isovolumetric relaxation period is started, the flow rate is reduced to zero again, and then the next cycle is carried out.

The updating method of the blood flow pressure peak value in the heart cavity comprises the following steps: the pressure of the blood flow in the heart chambers varies continuously during a cardiac cycle, and the pressure of the blood flow in the same part of the heart chambers in different cardiac cycles has approximately the same trend. When the P wave of the electrocardiogram reaches the peak, the pressure in the atrium and the ventricle begins to rise; at the moment, the atria contract, blood in the atria flows into the ventricles, and the pressure in the ventricles rises again at the position of an R wave of an electrocardiogram; at this time, the ventricles contract, approximately at the end of the T-wave.

Fig. 7 is a schematic diagram of the flow chart of updating the ventricular fibrillation count value in step 606 of fig. 6. Step 702 updates the real-time heart rate value, step 704 updates the real-time heart rate data sequence on the basis of the obtained real-time heart rate value, step 706 updates the shift registers x (N-4), x (N-3), x (N-2), x (N-1), x (N), x (N +1), x (N +2), x (N +3), x (N +4), and. 24 bits. Step 708 updates a ventricular fibrillation count value by a ventricular fibrillation counter equal to the number of real-time heart rate values in the shift register greater than the ventricular speed threshold.

Claims

1. Implanted medical equipment for recognizing ventricular fibrillation events by aid of blood flow parameters, which is characterized by comprising:

the storage circuit is used for storing an identification program for identifying the ventricular fibrillation through the electrocardiosignals, the blood flow velocity and the blood flow pressure;

calculating the ratio of the blood flow velocity or the blood flow pressure to the R peak in the shift register as a standard value P;

judging whether the electrocardiosignals meet the ventricular fibrillation counting condition to finish the preliminary identification of the ventricular fibrillation,

obtaining the current real-time heart rate value,

the real-time heart rate data sequence is continuously updated with the current real-time heart rate value,

if the real-time heart rate data sequence is larger than the rapid ventricular rate threshold value, adding 1 to the ventricular fibrillation count value,

updating the ventricular fibrillation count value, starting a backtracking window when the ventricular fibrillation count value reaches a threshold t1,

if the heart rate value located in the ventricular fibrillation area exists in the backtracking window, identifying the ventricular fibrillation area; otherwise, identifying as a fast chamber speed;

if the electrocardiosignals meet the ventricular fibrillation counting condition, starting a backtracking window to assist in identifying ventricular fibrillation events;

counting the number k of the ratio P of the blood flow velocity to the R peak or the ratio P of the blood flow pressure to the R peak in the backtracking window within a threshold range;

and if the electrocardiosignal does not meet the ventricular fibrillation counting condition or the numerical value k does not reach the threshold value h, returning and updating the real-time blood flow velocity or the blood pressure peak value and the R peak value.

2. Implanted medical equipment for assisting electrocardio signals in identifying ventricular fibrillation events through blood flow parameters is characterized by comprising:

obtaining the current real-time heart rate value,

updating the ventricular fibrillation count value, updating the ventricular rate count and the combined count when the ventricular fibrillation count value reaches a threshold t1, wherein the combined count is the ventricular fibrillation count + the ventricular rate count,

if the combined count reaches t2, determining whether the heart rate value in the ventricular fibrillation region exists in the backtracking window,

if so, identifying ventricular fibrillation; otherwise, continuously judging whether the heart rate value positioned in the rapid chamber velocity region exists in the backtracking window,

if so, identifying the rapid chamber speed; otherwise, identifying as the chamber speed;

if the electrocardiosignal meets the ventricular fibrillation counting condition, starting a backtracking window to assist in identifying ventricular fibrillation events;

3. The implanted medical device for assisting electrocardiosignal recognition of ventricular fibrillation events according to claim 2, wherein the updating method of the ventricular fibrillation count value comprises the following steps:

updating the real-time heart rate data sequence;

4. Implanted medical device for assisting cardiac electrical signals in identifying post-ventricular fibrillation shock therapy events, characterized in that said shock therapy event identification step comprises a ventricular fibrillation event identification step according to any one of claims 1 and 2, and if a ventricular fibrillation event is identified, a shock therapy is performed.

5. The implantable medical device for recognizing post-ventricular fibrillation shock therapy events according to the blood flow parameters of claim 4, wherein the medical system determines whether the cardiac electrical signals satisfy a ventricular fibrillation count condition by the medical device, and the determination of the ventricular fibrillation count condition comprises:

acquiring a current real-time heart rate value;

6. The implantable medical device for identifying post-ventricular fibrillation shock therapy events according to claim 5, wherein said step of determining whether the cardiac electrical signals satisfy the ventricular fibrillation count condition includes:

acquiring a current real-time heart rate value;

updating the ventricular fibrillation count value, and updating the ventricular rate count and the combined count when the ventricular fibrillation count value reaches a threshold t1, wherein the combined count is ventricular fibrillation count + ventricular rate count;

if so, identifying the ventricular fibrillation; otherwise, continuously judging whether the heart rate value positioned in the rapid chamber velocity area exists in the backtracking window;

7. The implantable medical device for identification of post-ventricular fibrillation shock therapy events according to claim 6, wherein the implantable medical device performs treatment by delivering pulses following identification of a shock therapy event.

8. An implanted medical system for identifying post-fibrillation shock therapy events using blood flow parameters to assist cardiac electrical signals, the implanted medical system comprising the implanted medical device of any one of claims 4-7, and further comprising:

a pulse generator consisting of a device housing and an internal circuit provided with sensing, storage, execution circuits;

9. The implantable medical system for identification of a post-fibrillation shock therapy event by cardiac electrical signals with the aid of blood flow parameters according to claim 8, wherein the electrode leads of the implantable medical system are selected from the group consisting of single lead, double lead, triple lead, and quadruple lead.

10. The implanted medical system for identification of post-ventricular fibrillation shock therapy events according to claim 8, wherein the information necessary for the pulse generator and the programmer of the implanted medical system to establish the far-field communication link includes communication channel, communication mode, communication frequency, communication modulation mode, and encryption key.