Artificial heart pump control method, control device and electronic equipment

Abstract

The invention discloses an artificial heart pump control method and device and electronic equipment, and the method comprises the steps: building a coupling simulation model of an artificial heart pump and a cardiovascular circulation system, and adding a rotating speed-cardiac output function between the rotating speed of the artificial heart pump and the cardiac output of the cardiovascular circulation system into the coupling simulation model; establishing a rotating speed-heart rate function between the heart rate and the rotating speed of the artificial heart pump based on a nonlinear fitting method; establishing a heart rate adaptive control module based on a rotating speed-heart rate function, and adding the heart rate adaptive control module to the coupling simulation model to establish a heart pump control model; the rotational speed is controlled based on the cardiac pump control model to adjust the heart rate and cardiac output. The heart rate self-adaptive control module is designed by taking the heart rate of the patient as a control variable, the heart rate and heart output are maintained near normal physiological values, the blood perfusion requirements in different physiological states can be met, and the dynamic performance of the artificial heart pump is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of biomedical engineering, and particularly to a control method, a control device and an electronic device for an artificial heart pump. Background Art

[0002] Heart failure has an extremely high mortality rate and is a common problem faced by the medical community today. Heart transplantation is the best solution for treating heart failure. However, the number of available hearts for transplantation each year is extremely small, and the success of transplantation is greatly affected by matching. Artificial heart pumps can be used as a bridge for heart transplantation and become an important treatment means to extend the survival period of heart failure patients. During the treatment of heart failure, maintaining the normal physiological characteristics of heart failure patients as much as possible is the key to the success of treatment.

[0003] In the prior art, the most widely used and technically mature is the continuous flow artificial heart pump, which uses a constant speed mode to assist the damaged heart to complete blood pumping. In clinical applications, the rotational speed of the artificial heart pump is manually adjusted to change the blood flow volume of the cardiovascular system during the auxiliary work. It has the following problems:

[0004] First, the rotational speed adjustment accuracy is low, and manual adjustment depends on the medical skills of the operator. Patients themselves and ordinary medical staff cannot meet the operation requirements, resulting in certain risks in manually adjusting the rotational speed and poor safety.

[0005] Second, the dynamic performance is poor and the response is slow. After manually setting a new rotational speed, the rotational speed remains unchanged for a certain period of time, and real-time following and dynamic adjustment cannot be achieved.

[0006] Third, the adaptability and stability are poor. Since the heart failure levels of different patients are different and the physiological states of patients are constantly changing, the blood perfusion requirements of the human body at different times are different. The blood flow volume under the constant speed mode assistance is fixed, and it is difficult to meet the blood perfusion requirements under different physiological states, making it easy for patients to have rejection reactions after implantation. Summary of the Invention

[0007] The present invention provides a control method, a control device and an electronic device for an artificial heart pump to solve the problems that the existing continuous flow artificial heart pump uses a manual adjustment method, resulting in low pump rotational speed adjustment accuracy, slow dynamic response, poor adaptability and stability, and can meet the blood perfusion requirements under different physiological states and improve the dynamic performance of the artificial heart pump.

[0008] According to one aspect of the present invention, a method for controlling an artificial heart pump is provided, including: establishing a coupled simulation model of the artificial heart pump and the cardiovascular circulatory system, and adding a rotational speed-cardiac output function between the rotational speed of the artificial heart pump and the cardiac output of the cardiovascular circulatory system to the coupled simulation model; establishing a rotational speed-heart rate function between the heart rate and the rotational speed of the artificial heart pump based on a non-linear fitting method; establishing a heart rate adaptive control module based on the rotational speed-heart rate function, and adding the heart rate adaptive control module to the coupled simulation model to establish a heart pump control model; controlling the rotational speed based on the heart pump control model to adjust the heart rate and the cardiac output.

[0009] Optionally, establishing the heart rate adaptive control module based on the rotational speed-heart rate function and adding the heart rate adaptive control module to the coupled simulation model to establish a heart pump control model includes: establishing a penalty function for the rotational speed; importing the rotational speed-heart rate function into the penalty function to establish the control law of the heart rate adaptive control module.

[0010] Optionally, the control law of the heart rate adaptive control module satisfies the following formula: where u(k) represents the rotational speed at time k, which is the input parameter of the rotational speed-heart rate function; φ(k) represents the pseudo partial derivative, which is used to simplify the rotational speed-heart rate function; λ represents the weight coefficient of the control input; HR(k) represents the heart rate at time k, which is the output parameter of the rotational speed-heart rate function; ρ k represents the step sequence.

[0011] Optionally, the rotational speed-cardiac output function is established by fitting based on the hydraulic performance curve of the artificial heart pump.

[0012] Optionally, the rotational speed-cardiac output function satisfies the following formula: where H represents the pressure difference between the inlet and outlet of the artificial heart pump; Q rp (t) represents the cardiac output at time t; ω(t) represents the rotational speed at time t; β a 、β b 、β c and β d represent hemodynamic coefficients.

[0013] Optionally, the rotational speed-heart rate function is established based on discrete system non-linear fitting; where the rotational speed-heart rate function is as follows: HR(k + 1) = f(HR(k), HR(k - 1), …, HR(k - n HR ), u(k), u(k - 1), …, u(k - n u ), where HR(k) represents the heart rate at time k, which is the output parameter of the rotational speed-heart rate function; nHR represents the output order; u(k) represents the rotational speed at time k, which is the input parameter of the rotational speed - heart rate function; n u represents the input order.

[0014] Optionally, establishing the coupled simulation model of the artificial heart pump and the cardiovascular circulatory system, and adding the rotational speed - cardiac output function between the rotational speed of the artificial heart pump and the cardiac output of the cardiovascular circulatory system in the coupled simulation model includes: establishing the cardiovascular electrical network model of the cardiovascular circulatory system based on the electrical network equivalent theory; connecting the artificial heart pump from the left ventricle to the aorta, and adding the corresponding branch electrical network model in the cardiovascular electrical network model to form a coupled electrical network model; performing nodal analysis on the coupled electrical network model, establishing the state equation, and establishing the coupled simulation model based on the state equation; adding the rotational speed - cardiac output function to the coupled simulation model.

[0015] Optionally, the motor used by the artificial heart pump is a bearingless permanent magnet motor.

[0016] According to another aspect of the present invention, there is provided an artificial heart pump control device, including: a first model creation module for establishing the coupled simulation model of the artificial heart pump and the cardiovascular circulatory system, and adding the rotational speed - cardiac output function between the rotational speed of the artificial heart pump and the cardiac output of the cardiovascular circulatory system in the coupled simulation model; a fitting module for establishing the rotational speed - heart rate function between the heart rate and the rotational speed of the artificial heart pump based on the nonlinear fitting method; a second model creation module for establishing a heart rate adaptive control module based on the rotational speed - heart rate function and adding the heart rate adaptive control module to the coupled simulation model to establish a heart pump control model; an execution module for controlling the rotational speed based on the heart pump control model to adjust the heart rate and the cardiac output.

[0017] According to another aspect of the present invention, there is provided an electronic device, the electronic device includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein, the memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute the above-mentioned artificial heart pump control method.

[0018] The technical solution of the embodiment of the present invention is to establish a coupled simulation model of an artificial heart pump and a cardiovascular circulatory system, and add a rotational speed - cardiac output function between the rotational speed of the artificial heart pump and the cardiac output of the cardiovascular circulatory system to the coupled simulation model; establish a rotational speed - heart rate function between the heart rate and the rotational speed of the artificial heart pump based on the non - linear fitting method. Further, establish a heart rate adaptive control module based on the rotational speed - heart rate function, and add the heart rate adaptive control module to the coupled simulation model to establish a heart pump control model; control the rotational speed based on the heart pump control model to adjust the heart rate and cardiac output, solving the problems that the existing continuous - flow artificial heart pumps adopt a manual adjustment method, resulting in low adjustment accuracy of the pump rotational speed, slow dynamic response, poor adaptability and stability, and being able to meet the blood perfusion requirements under different physiological states and improve the dynamic performance of the artificial heart pump.

[0019] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present invention, nor is it used to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0021] Figure 1 It is a flowchart of a method for controlling an artificial heart pump provided by an embodiment of the present invention;

[0022] Figure 2 It is a flowchart of a method for establishing a coupled simulation model of an artificial heart pump and a cardiovascular circulatory system provided by an embodiment of the present invention;

[0023] Figure 3 It is a schematic diagram of a coupled electrical network model of an artificial heart pump and a cardiovascular circulatory system provided by an embodiment of the present invention;

[0024] Figure 4 It is a schematic diagram of a simulation model of a method for controlling an artificial heart pump provided by an embodiment of the present invention;

[0025] Figure 5 It is a schematic diagram of a simulation result of a method for controlling an artificial heart pump based on heart rate adaption provided by an embodiment of the present invention;

[0026] Figure 6 It is a schematic diagram of the structure of a device for controlling an artificial heart pump provided by an embodiment of the present invention;

[0027] Figure 7 It is a schematic structural diagram of an electronic device for implementing the artificial heart pump control method according to an embodiment of the present invention. Detailed implementation manners

[0028] In order to enable those skilled in the art of the present technology to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0029] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above drawings are used to distinguish similar objects, and do not necessarily need to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present invention described here can be implemented in an order different from those illustrated or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units does not necessarily need to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0030] The control technology adjusted based on the body's metabolic needs is called physiological control. When heart failure patients are in different physiological states, the demand for blood perfusion in their bodies will also change. At this time, it is necessary to adjust the rotation speed of the artificial heart pump to match the blood flow required by the patient. Heart rate, as an important parameter that can reflect different physiological states of patients, is expected to improve the dynamic performance of the artificial heart pump if it can be used as a control variable of the system. Compared with blood pressure and blood flow, the method of obtaining heart rate is relatively simple and easy to monitor. Based on this, the present invention provides an artificial heart pump control method, which designs a model-free adaptive controller with the patient's heart rate as the control variable, and maintains the heart rate and cardiac output near normal physiological values by controlling the rotation speed of the artificial heart pump motor, so as to meet the blood perfusion requirements under different physiological states and improve the dynamic performance of the artificial heart pump.

[0031] Figure 1 It is a flowchart of an artificial heart pump control method provided by an embodiment of the present invention. Figure 2The figure is a schematic diagram of a connection structure between an artificial heart pump and a cardiovascular circulatory system provided by an embodiment of the present invention. This embodiment is applicable to scenarios where the automatic control of the artificial heart pump is performed with the patient's heart rate as the control variable. This method can be executed by an artificial heart pump control device, which can be implemented in the form of hardware and / or software, and the artificial heart pump control device can be configured in an electronic device. As Figure 1 and Figure 2 shown, the artificial heart pump control method of the present application includes the following steps:

[0032] S1: Establish a coupled simulation model of the artificial heart pump and the cardiovascular circulatory system, and add a speed-cardiac output function between the speed of the artificial heart pump and the cardiac output of the cardiovascular circulatory system to the coupled simulation model.

[0033] Among them, the coupled simulation model can be understood as a simulation model established based on the electrical network equivalent model of the cardiovascular circulatory system and the artificial heart pump. In this embodiment, the coupled simulation model includes partial differential equations of parts related to hemodynamic indexes such as the left ventricle, left atrium, systemic circulation, and artificial heart pump. The input of the coupled simulation model is parameters that can affect hemodynamic characteristics, including but not limited to: parameters of the artificial heart pump (including but not limited to: speed and hemodynamic coefficients), parameters of the cardiovascular circulatory system (including but not limited to: vascular resistance, compliance, blood flow inertia, cardiac elastic variables), and cardiac output target value. The cardiac output target value can be adaptively adjusted based on changes in the patient's physiological state (such as heart rate, peripheral resistance, etc.). The output of the coupled simulation model is parameters that can characterize hemodynamic characteristics, including but not limited to: real-time cardiac output, real-time blood pressure (including but not limited to: left ventricular pressure, left atrial pressure, and aortic pressure), real-time blood flow volume of the cardiovascular circulatory system, and pump flow of the artificial heart pump. It should be noted that the real-time blood flow volume of the cardiovascular circulatory system and the pump flow of the artificial heart pump satisfy a specific functional relationship (including but not limited to a constant difference relationship and a magnification relationship).

[0034] The speed-cardiac output function can be understood as a function established based on parameters related to hemodynamic indexes in the artificial heart pump. Optionally, the speed-cardiac output function is established by fitting based on the hydraulic performance curve of the artificial heart pump. After adding the speed-cardiac output function to the coupled simulation model, the coupled simulation model can use the speed as the independent variable and the cardiac output as the dependent variable. That is to say, by running the coupled simulation model, it is possible to maintain the cardiac output of the system at the cardiac output target value by adjusting the speed of the artificial heart pump.

[0035] S2: Establish a speed-heart rate function between the heart rate and the speed of the artificial heart pump based on a nonlinear fitting method.

[0036] Among them, the rotational speed-heart rate function can be understood as a non-linear function established by using the rotational speed as the function input parameter and the heart rate as the function output parameter.

[0037] Specifically, the part of the baroreflex feedback system of the cardiovascular system related to the heart rate is very complex, and a conventional mathematical model cannot establish a relationship between the heart rate and the motor rotational speed of the artificial heart pump. Accordingly, in this application, a large amount of data on the heart rate and the corresponding rotational speed of the artificial heart pump is subjected to non-linear fitting to establish the rotational speed-heart rate function.

[0038] In some embodiments, the rotational speed-heart rate function is established based on discrete system non-linear fitting. Among them, discrete system non-linear fitting can be understood as describing the complex mapping between the input parameter and the output parameter in the discrete system through a non-linear function, and solving the function parameters through an iterative optimization method to make the non-linear fitting curve as close as possible to the data points.

[0039] Optionally, the rotational speed-heart rate function is as Formula 1 below:

[0040] HR(k + 1) = f(HR(k), HR(k - 1), …, HR(k - n HR ), u(k), u(k - 1), …, u(k - n u )) (Formula 1)

[0041] Among them, HR(k) represents the heart rate at time k, which is the output parameter of the rotational speed-heart rate function; n HR represents the output order; u(k) represents the rotational speed at time k, which is the input parameter of the rotational speed-heart rate function; n u represents the input order.

[0042] In this embodiment, the input order n u and the output order n HR refer to the number of inputs (i.e., the rotational speed of the artificial heart pump) and outputs (i.e., the heart rate) in the past few time steps used to describe the system dynamic prediction in the control algorithm. The input order n u refers to the input (i.e., the rotational speed of the artificial heart pump) in the past few time steps being used to predict the current output (heart rate), while the output order n HR is the output (i.e., the heart rate) in the past few time steps being used to estimate the current input state. There are several ways to select the input order n u and the output order n HR , and the trial-and-error method is adopted in this patent to determine. For example, it can start from a small order (such as the input order n u = 1, the output order n HR= 1), and then gradually increase until the control performance no longer improves significantly. Returning to the specific case, assume that after adjusting the rotational speed of the artificial heart pump, the change in heart rate may occur within seconds to minutes, depending on the patient's physiological condition. For example, if the data sampling period is defined as 1 second, consider the inputs and outputs at several past time points. If the heart rate response reaches stability approximately 5 seconds after adjusting the rotational speed, the required input order n u is equal to 5.

[0043] S3: Establish a heart rate adaptive control module based on the rotational speed-heart rate function, and add the heart rate adaptive control module to the coupled simulation model to establish a heart pump control model.

[0044] Among them, the heart rate adaptive control module can be understood as a controller that uses the heart rate as a control variable for adaptive adjustment control. In this embodiment, the heart rate adaptive control module adopts a model-free adaptive control algorithm (Model-Free Adaptive Control, abbreviated as MFAC). MFAC can utilize the input parameters (such as rotational speed) and output parameters (such as heart rate) of the system to identify the dynamic characteristics of the system, and adjust the control strategy of the model according to the identification results. The heart rate adaptive control module uses the heart rate as a control variable. When the heart rate changes, it adjusts the rotational speed to respond to the heart rate change. In practical applications, the non-parametric model adaptive control theory can improve the control performance of the system through continuous learning and adjustment, realize heart rate adaptive physiological control, without the need to master the accurate mathematical model of the system in advance, and has great advantages in dealing with nonlinear problems, with high control accuracy and good robustness.

[0045] In this embodiment, the heart rate adaptive control module can make the heart rate follow the heart rate target value by controlling the rotational speed. Among them, the heart rate target value changes with the patient's physiological state (such as peripheral resistance, etc.).

[0046] S4: Control the rotational speed based on the heart pump control model to adjust the heart rate and cardiac output.

[0047] In this embodiment, the heart pump control model integrates the heart rate adaptive control module and the coupled simulation model, forms a heart rate closed-loop feedback through the heart rate adaptive control module, makes the heart rate follow the heart rate target value, and keeps the cardiac output near the cardiac output target value.

[0048] Specifically, during the control process of the artificial heart pump, the target heart rate value and the real-time heart rate are input into the heart pump control model. The heart rate adaptive control module outputs a control instruction according to the deviation between the input target heart rate value and the real-time heart rate, and adjusts the rotation speed of the artificial heart pump to maintain the heart rate and cardiac output near the target values required for the patient's physiological state. Thus, by adding a rotation speed-cardiac output function to the coupled simulation model of the artificial heart pump and the cardiovascular circulatory system, and establishing a heart rate adaptive control module designed with the patient's heart rate as the control variable, the heart rate and cardiac output are maintained near the normal physiological values, meeting the blood perfusion requirements under different physiological states, improving the dynamic performance, and enhancing the quality of life of heart failure patients.

[0049] Optionally, in the above step S3, a heart rate adaptive control module is established based on the rotation speed-heart rate function, and the heart rate adaptive control module is added to the coupled simulation model to establish a heart pump control model, including: establishing a penalty function for the rotation speed (i.e., the system input parameter); importing the rotation speed-heart rate function into the penalty function to establish the control law of the heart rate adaptive control module.

[0050] Optionally, the control law of the heart rate adaptive control module satisfies the following formula: where u(k) represents the rotation speed at time k, which is the input parameter of the rotation speed-heart rate function; φ(k) represents the pseudo partial derivative, which is used to simplify the rotation speed-heart rate function; λ represents the weight coefficient of the control input; HR(k) represents the heart rate at time k, which is the output parameter of the rotation speed-heart rate function; ρ k represents the step size sequence.

[0051] Specifically, the design process of the heart rate adaptive control module is as follows:

[0052] First, obtain the rotation speed-heart rate function shown in Formula 1, and this rotation speed-heart rate function adopts the mathematical expression of a non-linear discrete system.

[0053] When the non-linear discrete system shown in Formula 1 satisfies u(k)≠0, a pseudo partial derivative can be found to transform the system output (i.e., the heart rate) into the form shown in Formula 2,

[0054]

[0055] where, represents the pseudo partial derivative; b is a positive number set artificially.

[0056] Secondly, design the control law of MFAC. To improve the control accuracy and robustness of the system, a penalty function shown in Formula 3 is designed for the system input:

[0057]

[0058] where, The system output target value (i.e., the heart rate target value) is denoted as, and the weight coefficient of the control input is denoted as λ.

[0059] By introducing the rotational speed - heart rate function (i.e., Equation 1) into the penalty function (i.e., Equation 3), the control law of MFAC can be further derived as

[0060]

[0061] where ρ k denotes the step - size sequence.

[0062] As can be seen from Equation 4, the control law of MFAC does not depend on the mathematical model, and the control process can be completed only by giving the input and output of the system. The pseudo - partial derivative φ(k) is crucial in the design of MFAC. In this application, the criterion function shown in Equation 5 can be used to derive the unknown term φ(k).

[0063]

[0064] where u represents the weight coefficient of the pseudo - partial derivative; denotes the estimated value of φ(k).

[0065] By minimizing the criterion function shown in Equation 5, the pseudo - partial derivative estimation function shown in Equation 6 can be obtained:

[0066]

[0067] where μ represents the weight coefficient of the pseudo - partial derivative; η k denotes the step - size parameter.

[0068] According to the theory of MFAC, Equation 1 can be dynamically linearized into the following Equation 7:

[0069] HR(k + 1)=HR(k)+φ(k)(u(k)-u(k - 1)) (Equation 7)

[0070] Combining the penalty function shown in Equation 3 and the pseudo - partial derivative estimation function shown in Equation 6, the expression of the heart - rate adaptive physiological control penalty function based on MFAC can be established as

[0071] J(u(k))=(HR d (k + 1)-HR(k + 1)) 2 +λ(u(k)-u(k - 1)) 2 (Equation 8)

[0072]

[0073] where HR d(k+1) represents the reference value of heart rate at the k+1th moment, in bits / min;

[0074] HR(k) represents the measured value of heart rate at the kth moment, and the unit is Bit / min;

[0075] u(k) represents the speed of the motor of the artificial heart pump at the kth moment, and the unit is r / min.

[0076] By combining the above formulas 7, 8, and 9, we can obtain the pseudo partial derivative estimation algorithm (see formula 10) and control law (see formula 11) for the adaptive physiological control of the heart rate of the artificial heart pump.

[0077]

[0078] Here, ||·|| represents the norm of the matrix.

[0079] Figure 2 This is a flow chart of a method for establishing a coupled simulation model of an artificial heart pump and a cardiovascular circulatory system according to an embodiment of the present invention. Figure 2 As shown, in the above step S1, a coupled simulation model of the artificial heart pump and the cardiovascular circulatory system is established, and a speed-cardiac output function between the speed of the artificial heart pump and the cardiac output of the cardiovascular circulatory system is added to the coupled simulation model, including:

[0080] S101: Establish a cardiovascular electrical network model of the cardiovascular circulatory system based on the electrical network equivalent theory.

[0081] S102: Connecting the artificial heart pump from the left ventricle to the aorta, and adding a corresponding branch electrical network model to the cardiovascular electrical network model to form a coupled electrical network model.

[0082] Figure 3 Schematic diagram of a coupled electrical network model of an artificial heart pump and a cardiovascular circulatory system provided by an embodiment of the present invention. Figure 3 As shown in Figure 1, based on the actual clinical application of artificial heart pumps, the artificial heart pump is connected from the left ventricle to the aorta in the cardiovascular electrical network model, forming a coupled electrical network model of the cardiovascular circulatory system and the artificial heart pump. Figure 3 As shown, the paths from left to right in the lower half of the model represent left atrial pressure x2, left ventricular pressure x1, arterial pressure x3, aortic pressure x4 and blood flow x5, respectively. The uppermost part passes through R S The path from right to left back to the left atrium represents the entire systemic-pulmonary circulation; the path through x6 represents the connection of the artificial heart pump from the left ventricle to the aorta. Figure 3 As shown, C R$C(t)$ represents the compliance of the left atrium and the left ventricle. The blood vessel wall is elastic, and compliance is used to characterize the degree to which the blood vessel volume changes with blood pressure; diode D M and D A respectively represent the mitral valve and the aortic valve. Their conduction and cutoff respectively represent the opening and closing of the valves; R M and R A are respectively the mitral valve flow resistance and the aortic valve flow resistance; L C represents the inertia of the blood, and R C and C A respectively represent the peripheral resistance and the arterial compliance. The time-varying quantity of the model is the volume characteristic of the left ventricle, which is reflected by a time-varying capacitance value $C(t)$, and it is the reciprocal of the ventricular elastic function $E(t)$. In the model of this application, it is assumed that the right atrium, the right ventricle and the pulmonary circulation system are normal, that is, the influence of the artificial heart pump on these parts can be ignored. Therefore, the cardiovascular system in this coupled electrical network model is divided into 5 parts (left ventricular pressure $x1$, left atrial pressure $x2$, arterial pressure $x3$, aortic pressure $x4$ and blood flow $x5$) and the pump flow $x6$ of the artificial heart pump to form a 6th-order coupled electrical network model.

[0083] S103: Perform nodal analysis on the coupled electrical network model, establish the state equation, and establish a coupled simulation model based on the state equation.

[0084] S104: Add the rotational speed - cardiac output function to the coupled simulation model.

[0085] Specifically, after obtaining the electrical network equivalent model of the cardiovascular circulation system and the artificial heart pump, by performing Kirchhoff's theorem analysis on the nodes in the electrical network equivalent model, the state equations of each coupled simulation model.

[0086] Optionally, the rotational speed - cardiac output function satisfies Formula XII shown as follows:

[0087]

[0088] where $H$ represents the pressure difference between the inlet and outlet of the artificial heart pump; $Q$ rp $(t)$ represents the cardiac output at time $t$; $\omega(t)$ represents the rotational speed at time $t$; $\beta$ a , $\beta$ b , $\beta$ c and $\beta$ d represent hemodynamic coefficients.

[0089] See Figure 3 As shown, the artificial heart pump is connected in parallel between the left ventricle (inlet) and the aorta (outlet) (to assist the damaged left ventricle in pumping blood), so the pressure difference $H$ between the inlet and outlet of the artificial heart pump is equal to the difference between the left ventricular pressure and the aortic pressure.

[0090] In some embodiments, the motor used in the artificial heart pump is a bearingless permanent magnet motor. Among them, the bearingless permanent magnet motor can achieve non-contact support, significantly reduce mechanical losses, reduce the risk of particulate contamination caused by wear, and improve blood compatibility.

[0091] Figure 4 This is a schematic diagram of a simulation model of a control method for an artificial heart pump provided by an embodiment of the present invention. Refer to Figure 4 As shown, by constructing a heart pump control simulation model, the hemodynamic characteristics during the assistance of an artificial heart pump with a heart rate adaptive control method can be simulated to verify the effectiveness of the heart rate adaptive physiological control method.

[0092] The heart pump control simulation model includes a coupled simulation model part and a heart rate adaptive control module part. Among them, the controller of the coupled simulation model part integrates partial differential equations of multiple parts related to hemodynamic indexes such as the left ventricle, left atrium, systemic circulation, and artificial heart pump. The inputs of the coupled simulation model include, but are not limited to: the feedback value of the cardiac output CO and the feedback value of the heart rate HR; the outputs of the coupled simulation model include, but are not limited to: the real-time cardiac output CO, the real-time blood pressure (including, but not limited to: the left ventricular pressure Plv, the left atrial pressure Pla, and the aortic pressure Pao), the real-time blood flow Qao of the cardiovascular circulatory system, and the pump flow Qpump of the artificial heart pump; EF represents the heart failure grade. The heart rate adaptive control module uses the heart rate as the control variable, and when the heart rate changes, it adjusts the rotational speed to respond to the heart rate change.

[0093] During the simulation process of the heart pump control simulation model, the basic parameters of the coupled simulation model are set, the total simulation time is set to 60 s, and the entire assistance process is divided into two time periods. The first half (0 - 30 s) is the state when the patient is at rest normally. At this time, the peripheral resistance representing the patient's physiological state is set to 1.0 mmHg·s / ml; in the second half (30 - 60 s), the peripheral resistance representing the patient's physiological state is set to 0.7 mmHg·s / ml to simulate the reaction of the artificial heart pump when the physiological state changes to a slightly exercising state, and then its dynamic performance is evaluated. In addition, the time step is set to Δt = 0.0001 s, and the heart failure grade is set to moderate heart failure (30% EF).

[0094] Figure 5 This is a schematic diagram of the simulation results of a control method for an artificial heart pump based on heart rate adaptation provided by an embodiment of the present invention. Refer to Figure 5 As shown, since the feedback of the cardiac output and heart rate on the dynamic performance is more obvious, two indexes of the cardiac output and heart rate are selected for analysis, and at the same time, the responses in different states during heart failure are added for comparison.

[0095] Among them, Figure 5(a) in the middle represents the cardiac output response results, Ⅰa represents the cardiac output response results in different states of heart failure; Ⅱa represents the cardiac output response results in different states under the heart rate adaptive control mode. Figure 5 Middle (b) shows the heart rate response results, Ib shows the heart rate response results in different states during heart failure; IIb shows the heart rate response results in different states under the heart rate adaptive control mode. Figure 5 Middle (c) shows the curve of aortic pressure changing with time, Ic shows the curve of aortic pressure changing with time in different states of heart failure; IIc shows the curve of aortic pressure changing with time in different states under the heart rate adaptive control mode. Figure 5 Middle (d) represents the speed curve, and IId represents the speed curves of different states under the heart rate adaptive control mode.

[0096] See also Figure 5 The cardiac output response results shown in (a) show that in the first half of the resting state, while the failing heart can achieve a cardiac output of 4 L / min, this is significantly lower than the normal blood flow requirement of the human body. Furthermore, when the physiological state shifts from rest to mild exercise, due to the patient's damaged heart and significantly insufficient pumping capacity, the system's cardiac output can only reach 6 L / min, far short of the 8 L / min blood perfusion requirement during mild exercise, resulting in insufficient blood supply. Looking at the results of heart rate adaptive physiological control, the system's blood flow remains stable at 5.2 L / min and 8 L / min during rest and mild exercise, respectively, meeting the blood perfusion requirements in different states. Although the cardiac output curve fluctuates slightly when the physiological state changes, the curve overshoot is small, and the overall transition is relatively natural, indicating that the controller can respond quickly to disturbances and has good control performance.

[0097] See also Figure 5 The heart rate change curve shown in (b) shows that the heart rate of the failing heart in the resting state is in the range of 70 to 80 Bit / min, which is slightly higher than the ideal heart rate value in the resting state. When switching to a state of light exercise, it can be clearly seen that the failing heart's heart rate soars due to insufficient blood pumping, which is extremely detrimental to the patient's health and requires immediate intervention with an artificial heart pump to assist in pumping blood. In contrast, the results of adaptive physiological control of heart rate are more ideal. With the assistance of the artificial heart pump, the heart rate of the failing heart is maintained at the target heart rate values of 60 Bit / min and 70 Bit / min in two physiological states, respectively, achieving adaptive heart rate regulation, which helps promote the recovery of the damaged heart.

[0098] See also Figure 5As shown in Fig. (c), the aortic pressure change curve indicates that, as can be seen from the figure, the aortic pressure of the failing heart is already low at rest. This is because after heart failure, the left ventricular pumping ability is insufficient and the aortic pressure cannot rise. After transitioning to a mild exercise state, the average aortic pressure of the failing heart slightly decreases because the damaged heart is willing but unable to do enough. If the patient is in a strenuous exercise state, it will be even more dangerous. After being assisted by an artificial heart pump using the heart rate adaptive physiological control method, the aortic pressure is within the normal physiological value range both at rest and in the mild exercise state. When the physiological state changes from rest to mild exercise, the overall aortic pressure of the system slightly increases to meet the increased dynamic demand for blood perfusion volume.

[0099] See Figure 5 The rotational speed curve shown in Fig. (b). At rest, the rotational speed of the artificial heart pump changes periodically within a range because the heart rate adaptive physiological control method is based on the blood bionic pulsation strategy, which improves the blood pulsatility while enhancing the dynamic performance of the system. At the moment of transitioning from rest to a mild exercise state, the overall rotational speed of the artificial heart pump slightly increases to output more blood volume to meet the dynamic demand for blood perfusion.

[0100] See Figure 5 As shown in the simulation results, the dynamic performance of the artificial heart pump under the heart rate adaptive physiological control mode is good.

[0101] Based on the same inventive concept as the above embodiments, the embodiments of the present invention also provide an artificial heart pump control device. The artificial heart pump control device provided by the embodiments of the present invention can execute the artificial heart pump control method provided by any embodiment of the present invention and has the corresponding functional modules and beneficial effects for executing the method.

[0102] Figure 6 It is a schematic structural diagram of an artificial heart pump control device provided by an embodiment of the present invention. As Figure 6 shown, the artificial heart pump control device includes: a first model creation module 101, a fitting module 102, a second model creation module 103, and an execution module 104.

[0103] Among them, the first model creation module 101 is used to establish a coupled simulation model of the artificial heart pump and the cardiovascular circulatory system, and add a rotational speed - cardiac output function between the rotational speed of the artificial heart pump and the cardiac output of the cardiovascular circulatory system to the coupled simulation model; the fitting module 102 is used to establish a rotational speed - heart rate function between the heart rate and the rotational speed of the artificial heart pump based on the non - linear fitting method; the second model creation module 103 is used to establish a heart rate adaptive control module based on the rotational speed - heart rate function, and add the heart rate adaptive control module to the coupled simulation model to establish a heart pump control model; the execution module 104 is used to control the rotational speed based on the heart pump control model to adjust the heart rate and cardiac output.

[0104] Based on the above - mentioned embodiments, an embodiment of the present invention further provides an electronic device, which includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein, the memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute the above - mentioned artificial heart pump control method.

[0105] Figure 7 A schematic structural diagram of an electronic device for implementing the artificial heart pump control method of the embodiments of the present invention. The electronic device is intended to represent various forms of digital computers, such as, laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as, personal digital processors, cellular phones, smart phones, wearable devices (such as helmets, glasses, watches, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are only examples and are not intended to limit the implementation of the present invention described and / or claimed herein.

[0106] As Figure 7 shown, the electronic device 10 includes at least one processor 11, and a memory communicatively connected to the at least one processor 11, such as a read - only memory (ROM) 12, a random - access memory (RAM) 13, etc. Among them, the memory stores a computer program executable by the at least one processor, and the processor 11 can execute various appropriate actions and processes according to the computer program stored in the read - only memory (ROM) 12 or the computer program loaded from the storage unit 18 into the random - access memory (RAM) 13. In the RAM 13, various programs and data required for the operation of the electronic device 10 can also be stored. The processor 11, the ROM 12, and the RAM 13 are connected to each other through a bus 14. The input / output (I / O) interface 15 is also connected to the bus 14.

[0107] Multiple components in the electronic device 10 are connected to the I / O interface 15, including: an input unit 16, such as a keyboard, a mouse, etc.; an output unit 17, such as various types of displays, speakers, etc.; a storage unit 18, such as a disk, an optical disc, etc.; and a communication unit 19, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 19 allows the electronic device 10 to exchange information / data with other devices via a computer network such as the Internet and / or various telecommunication networks.

[0108] The processor 11 can be various general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of the processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various dedicated artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. The processor 11 executes the various methods and processes described above, such as the above-mentioned artificial heart pump control method.

[0109] In some embodiments, the above-mentioned artificial heart pump control method can be implemented as a computer program, which is tangibly contained in a computer-readable storage medium, such as the storage unit 18. In some embodiments, part or all of the computer program can be loaded and / or installed onto the electronic device 10 via the ROM 12 and / or the communication unit 19. When the computer program is loaded into the RAM 13 and executed by the processor 11, one or more steps of the above-described artificial heart pump control method can be executed. Alternatively, in other embodiments, the processor 11 can be configured to execute the above-mentioned artificial heart pump control method in any other suitable manner (e.g., by means of firmware).

[0110] The various embodiments of the systems and technologies described above in this document can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SOCs), complex programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments can include: being implemented in one or more computer programs, which can be executed and / or interpreted on a programmable system including at least one programmable processor, and the programmable processor can be a special or general-purpose programmable processor, and can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit the data and instructions to the storage system, the at least one input device, and the at least one output device.

[0111] A computer program for implementing the method of the present invention can be written in any combination of one or more programming languages. These computer programs can be provided to a processor of a general purpose computer, a special purpose computer, or other programmable data processing apparatus, such that the computer programs, when executed by the processor, cause the functions / operations specified in the flowchart and / or block diagram to be implemented. The computer programs can be executed entirely on the machine, partly on the machine, as a stand-alone software package partly on the machine and partly on a remote machine, or entirely on the remote machine or server.

[0112] In the context of the present invention, a computer-readable storage medium can be a tangible medium that can contain or store a computer program for use by or in connection with an instruction execution system, apparatus, or device. The computer-readable storage medium can include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. Alternatively, the computer-readable storage medium can be a machine-readable signal medium. More specific examples of the machine-readable storage medium would include an electrical connection based on one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0113] In order to provide interaction with a user, the systems and techniques described herein can be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and a pointing device (e.g., a mouse or a trackball) by which the user can provide input to the electronic device. Other kinds of devices can also be used to provide interaction with the user; for example, the feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including acoustic input, speech input, or tactile input).

[0114] The systems and techniques described herein can be implemented in a computing system that includes backend components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes frontend components (e.g., a user computer having a graphical user interface or a web browser through which a user can interact with an implementation of the systems and techniques described herein), or a computing system that includes any combination of such backend, middleware, or frontend components. The components of the system can be interconnected with each other by digital data communication in any form or medium (e.g., a communication network). Examples of communication networks include: local area network (LAN), wide area network (WAN), blockchain network, and the Internet.

[0115] A computing system can include a client and a server. The client and the server are generally remote from each other and typically interact via a communication network. The client-server relationship is created by computer programs running on respective computers and having a client-server relationship with each other. A server can be a cloud server, also known as a cloud computing server or a cloud host, which is a host product in the cloud computing service system, and solves the defects of difficult management and weak business scalability existing in traditional physical hosts and VPS services.

[0116] It should be understood that various forms of the processes shown above can be used, with steps reordered, added, or deleted. For example, the steps recited in the present invention can be executed in parallel, sequentially, or in a different order, as long as the desired results of the technical solution of the present invention can be achieved, and no limitation is imposed herein.

[0117] The above specific embodiments do not constitute a limitation on the protection scope of the present invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for controlling an artificial heart pump, characterized in that, Including: Establishing a coupled simulation model of the artificial heart pump and the cardiovascular circulatory system, and adding a rotational speed - cardiac output function between the rotational speed of the artificial heart pump and the cardiac output of the cardiovascular circulatory system to the coupled simulation model; Establishing a rotational speed - heart rate function between the heart rate and the rotational speed of the artificial heart pump based on a non - linear fitting method; Establishing a heart rate adaptive control module based on the rotational speed - heart rate function, and adding the heart rate adaptive control module to the coupled simulation model to establish a heart pump control model; Controlling the rotational speed based on the heart pump control model to adjust the heart rate and the cardiac output.

2. The artificial heart pump control method according to claim 1, characterized in that, The establishing a heart rate adaptive control module based on the rotational speed - heart rate function, and adding the heart rate adaptive control module to the coupled simulation model to establish a heart pump control model includes: Establishing a penalty function for the rotational speed; Importing the rotational speed - heart rate function into the penalty function to establish the control law of the heart rate adaptive control module.

3. The artificial heart pump control method according to claim 2, characterized in that, The control law of the heart rate adaptive control module satisfies the following formula: Among them, u(k) represents the rotational speed at time k and is the input parameter of the rotational speed - heart rate function; φ(k) represents the pseudo partial derivative and is used to simplify the rotational speed - heart rate function; λ represents the weight coefficient of the control input; HR(k) represents the heart rate at time k and is the output parameter of the rotational speed - heart rate function; ρ k represents the step sequence.

4. The artificial heart pump control method according to claim 1, characterized in that, The rotational speed - cardiac output function is established by fitting based on the hydraulic performance curve of the artificial heart pump.

5. The artificial heart pump control method according to claim 4, characterized in that, The rotational speed - cardiac output function satisfies the following formula: Among them, H represents the pressure difference between the inlet and outlet of the artificial heart pump; Q rp (t) represents the cardiac output at time t; ω(t) represents the rotational speed at time t; β a , β b , β c and β d represent hemodynamic coefficients.

6. The artificial heart pump control method according to claim 1, characterized in that, The rotational speed - heart rate function is established based on discrete system non - linear fitting; wherein, the rotational speed - heart rate function is as follows: HR(k + 1) = f(HR(k), HR(k - 1), …, HR(k - n HR ), u(k), u(k - 1), …, u(k - n u )) Among them, HR(k) represents the heart rate at time k and is the output parameter of the rotation speed-heart rate function; n HR represents the output order; u(k) represents the rotation speed at time k and is the input parameter of the rotation speed-heart rate function; n u represents the input order.

7. The artificial heart pump control method according to claim 1, wherein The establishing a coupled simulation model of the artificial heart pump and the cardiovascular circulatory system, and adding a rotational speed - cardiac output function between the rotational speed of the artificial heart pump and the cardiac output of the cardiovascular circulatory system to the coupled simulation model includes: Establishing a cardiovascular electrical network model of the cardiovascular circulatory system based on the electrical network equivalent theory; Connecting the artificial heart pump from the left ventricle to the aorta, and adding a corresponding branch electrical network model to the cardiovascular electrical network model to form a coupled electrical network model; Performing nodal analysis on the coupled electrical network model to establish a state equation, and establishing the coupled simulation model based on the state equation; Adding the rotational speed - cardiac output function to the coupled simulation model.

8. The artificial heart pump control method according to any one of claims 1-7, characterized in that, The motor used by the artificial heart pump is a bearingless permanent magnet motor.

9. An artificial heart pump control device, characterized in that, Including: A first model creation module for establishing a coupled simulation model of the artificial heart pump and the cardiovascular circulatory system, and adding a rotational speed - cardiac output function between the rotational speed of the artificial heart pump and the cardiac output of the cardiovascular circulatory system to the coupled simulation model; A fitting module for establishing a rotational speed - heart rate function between the heart rate and the rotational speed of the artificial heart pump based on a non - linear fitting method; A second model creation module for establishing a heart rate adaptive control module based on the rotational speed - heart rate function, and adding the heart rate adaptive control module to the coupled simulation model to establish a heart pump control model; An execution module for controlling the rotational speed based on the heart pump control model to adjust the heart rate and the cardiac output.

10. An electronic device, characterized in that, The electronic device includes: At least one processor; and, A memory communicatively connected to the at least one processor; wherein, The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor to enable the at least one processor to execute the artificial heart pump control method according to any one of claims 1-8.

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