Test system and method for heart valve prosthesis implant

Abstract

The invention discloses a test system and method for an artificial heart valve implant, and relates to the technical field of medical instrument detection. The system comprises a ventricle simulator, an atrium simulator, a circulation loop, a high-speed camera and a laser generator, wherein an artificial heart valve is arranged in the high-transparency compliance valve testing cavity, and the circulation loop is composed of a blood vessel compliance simulator and a blood vessel damping simulator. The circulation loop simulates a blood flowing environment for the artificial heart valve, and a flowing medium is added with tracer particle turbid liquid; the ventricle simulator, the atrium simulator, the vascular damper and the vascular compliance simulator respectively provide power, storage space, resistance and pulse pressure for the flowing medium; and the laser generator and the high-speed camera act together to obtain a particle image behind the artificial heart valve. The particle image is uploaded to a computer for heart valve pulsating flow field visualization analysis based on the digital particle image velocity measurement technology, and therefore quantitative analysis of the risk after the heart valve is implanted into the expected position is achieved.

Description

Technical Field

[0001] The present application relates to the field of medical device testing technology, and in particular to a testing system and method for artificial heart valve implants. Background Art

[0002] In 2002, Professor Alain G. Cribier of France successfully completed the world's first human transcatheter aortic valve implantation (TAVI), which was later called transcatheter aortic valve replacement (TAVR). This technology introduces an interventional catheter through the femoral artery, delivers the artificial heart valve to the aortic valve area and deploys it, thereby restoring valve function without opening the chest, greatly reducing the surgical trauma of the patient and accelerating the postoperative recovery process.

[0003] For these high-risk patients or those with contraindications to cardiac surgery, transcatheter aortic valve implantation can now be used as an effective treatment. Recent studies have shown that for patients with severe aortic stenosis who cannot undergo surgery, TAVI can reduce mortality by 46% compared with drug treatment and significantly improve the quality of life of patients.

[0004] The design of artificial heart valves incorporates a variety of materials, including metal stents and biological leaflets, which may interact adversely with blood components after implantation. A deeper understanding of these interactions may help predict potential thrombosis after device implantation, and quantitative assessment of the potential thrombotic and hemolytic risks of heart valve replacement is an essential part of the design validation of these devices. Due to the presence of multidimensionally associated hemodynamic and biochemical processes, for example, platelet activation / rupture, platelet deposition, and clot formation at the blood / material interface due to high shear stress. Processes that lead to blood damage include: the presence of turbulence associated with heart valves, such as blood flow stagnation and high shear stress.

[0005] At present, the evaluation of the thrombosis and hemolysis of heart valve implants is mainly carried out through ex vivo blood evaluation or preclinical trials. Although the ex vivo blood evaluation can simulate the temperature, pressure, flow and other boundary conditions of the human body environment, there is inevitably a risk of coagulation when the blood contacts the inner wall of the device, which will lead to inaccurate embolus data measured in the final blood. Preclinical trials mainly involve releasing the implant into large animals and preliminarily judging the thrombosis and hemolysis risks of valve products by monitoring various blood indicators of the animals after implantation. Because the blood vessels, pressure and flow parameters of animal sources and humans are different, the test parameters can only be used as a qualitative evaluation, and the current large animal experiments are very expensive, and the economic burden on companies to carry out related testing and research is very high. Summary of the invention

[0006] In view of this, the main purpose of the present application is to provide a testing system and method for artificial heart valve implants, with the aim of achieving quantitative analysis of thrombosis and potential hemolysis risks after the heart valve is implanted in the intended location.

[0007] In a first aspect, the present application provides a test system for an artificial heart valve implant, the system comprising: a ventricular simulator, an atrial simulator, a highly transparent compliance valve test chamber, a vascular compliance simulator, a vascular damping simulator, a high-speed camera, and a laser generator;

[0008] The ventricle simulator, the atrial simulator, the high-transparency compliance valve test chamber, the vascular compliance simulator, and the vascular damping simulator are interconnected through pipelines to form a circulation loop. An artificial heart valve implant is arranged in the high-transparency compliance valve test chamber. During the test, the circulation loop simulates the blood flow environment of the artificial heart valve implant in the human body.

[0009] A ventricular simulator is used to provide power to a flowing medium in the pipeline; wherein the flowing medium in the pipeline is added with a tracer particle suspension;

[0010] an atrial simulator, which is used to store the flowing medium in the tube;

[0011] Vascular dampers are used to provide resistance to the flowing medium in the pipeline;

[0012] A vascular compliance simulator, used to provide pulse pressure to the flowing medium in the tube;

[0013] Highly transparent and compliant valve test chamber, used to provide a shooting window for high-speed cameras;

[0014] A laser generator, used for irradiating laser light into the high-transparent compliance valve test cavity;

[0015] A high-speed camera is used to obtain particle images behind the artificial heart valve implant after laser irradiation, and upload the particle images to a computer for visualization analysis of the heart valve pulsating flow field based on digital particle image velocimetry technology.

[0016] In some implementations of the first aspect of the present application, the artificial heart valve implant is one of an artificial aortic valve, an artificial pulmonary valve, an artificial mitral valve, and an artificial tricuspid valve.

[0017] In some implementations of the first aspect of the present application, when the artificial heart valve implant is an artificial aortic valve or an artificial pulmonary valve, in the circulation loop, the atrial simulator, the ventricular simulator, and the high-transparency compliance valve test chamber are connected in sequence.

[0018] In some implementations of the first aspect of the present application, when the artificial heart valve implant is an artificial mitral valve or an artificial tricuspid valve, in the circulation loop, the atrial simulator, the high-transparency compliance valve test chamber and the ventricular simulator are connected in sequence.

[0019] In some implementations of the first aspect of the present application, the high-speed camera uses a dual-frame mode to acquire particle images.

[0020] In some implementations of the first aspect of the present application, the ventricular simulator regulates pressure and cardiac output through a high-power voice coil motor to provide power for the flowing medium in the pipeline.

[0021] In some implementations of the first aspect of the present application, the tracer particle suspension uses hollow glass beads as tracer particles.

[0022] A second aspect of the present application provides a method for testing an artificial heart valve implant, the method comprising:

[0023] An artificial heart valve implant is arranged in the high-transparency compliance test chamber, and a blood flow environment in a human body is simulated in the high-transparency compliance test chamber;

[0024] Irradiating a laser into a high-transparency compliance test cavity, wherein a tracer particle suspension is added to a flowing medium in the high-transparency compliance test cavity;

[0025] A particle image is obtained behind the artificial heart valve implant after laser irradiation, and an analysis view of the heart valve pulsating flow field is generated based on the particle image.

[0026] In some implementations of the second aspect of the present application, the analysis view is a particle velocity field analysis view, wherein the particle velocity field analysis view is used to describe the particle velocity distribution in the normal plane of the heart valve axis at multiple contraction moments and multiple diastole moments in at least one cardiac cycle.

[0027] In some implementations of the second aspect of the present application, the method further includes:

[0028] Based on the particle velocity distribution in the normal plane of the heart valve axis at multiple contraction moments and multiple relaxation moments in at least one cardiac cycle, a particle shear stress field analysis view is generated, wherein the particle shear stress field analysis view is used to describe the particle shear stress distribution in the normal plane of the heart valve axis at multiple contraction moments and multiple relaxation moments in at least one cardiac cycle.

[0029] The technical solution provided by the present application has the following beneficial effects: a test system consisting of a ventricular simulator, an atrial simulator, a high-transparency compliance valve test chamber, a vascular compliance simulator, a vascular damping simulator, a high-speed camera and a laser generator is constructed; in the test system, the ventricular simulator, the atrial simulator, the high-transparency compliance valve test chamber, the vascular compliance simulator and the vascular damping simulator are interconnected through pipelines to form a circulation loop, an artificial heart valve is implanted in the high-transparency compliance valve test chamber, and during the test, the circulation loop passes through the ventricular simulator, the atrial simulator, the vascular compliance simulator and the vascular damping simulator. The damper, vascular compliance simulator, and high-transparency compliance valve test chamber simulate the blood flow environment of artificial heart valve implants in the human body, thereby providing accurate data support; the flow medium in the pipeline is added with tracer particle suspension; the laser generator is used to irradiate the laser to the high-transparency compliance valve test chamber to form a visualized flow field; the particle image behind the artificial heart valve implant after laser irradiation is obtained by a high-speed camera, and the particle image is uploaded to a computer to perform a visualized analysis of the heart valve pulsation flow field based on the digital particle image velocimetry technology. By analyzing the particle images captured by the high-speed camera using the digital particle image velocimetry technology, various parameters in the flow field can be calculated, so that the thrombosis and potential hemolysis risks after the heart valve is implanted in the expected position can be quantitatively analyzed. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A schematic diagram of the structure of a test system for an artificial heart valve implant provided in an embodiment of the present application;

[0031] Figure 2 A schematic diagram of the structure of a circulation loop provided in an embodiment of the present application;

[0032] Figure 3 A schematic diagram of the structure of another circulation loop provided in an embodiment of the present application;

[0033] Figure 4 A schematic diagram of the valve structure provided in an embodiment of the present application;

[0034] Figure 5 A schematic diagram of a particle image provided in an embodiment of the present application;

[0035] Figure 6 A schematic diagram of a particle velocity field analysis view provided in an embodiment of the present application;

[0036] Figure 7 A schematic diagram of a particle shear stress field analysis view provided in an embodiment of the present application;

[0037] Figure 8 A schematic flow chart of a method for testing an artificial heart valve implant provided in an embodiment of the present application. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0039] See also Figure 1 As shown, an embodiment of the present application provides a testing system for an artificial heart valve implant, which comprises a ventricular simulator 1, an atrial simulator 2, a high-transparency compliance valve test chamber 3, a vascular compliance simulator 4, a vascular damping simulator 5, a high-speed camera 6 and a laser generator 7.

[0040] In the system, the ventricular simulator 1, the atrial simulator 2, the high-transparency compliance valve test chamber 3, the vascular compliance simulator 4, and the vascular damping simulator 5 can be interconnected through pipelines to form a closed-loop circulation circuit.

[0041] In the circulation loop, the high-transparency compliance valve test chamber 3 is the core area, and the artificial heart valve implant to be tested is built in. The flow medium in the pipeline flows into the inlet of the high-transparency compliance valve test chamber 3, and flows out of the high-transparency compliance valve test chamber 3 through the artificial heart valve implant. Among them, the artificial heart valve implant refers to an artificial organ that can be implanted in the human heart to replace the original heart valve, make blood flow in one direction, and have the function of a natural heart valve.

[0042] At the same time, in order to visualize the flow field, tracer particle suspension is added to the flow medium in the pipeline. In addition, in order to ensure the authenticity of the simulated environment, the temperature of the flow medium is controllable.

[0043] During the test, the medium flowing in the pipe of the circulation loop simulates the contraction and relaxation of the heart, as well as the compliance and damping characteristics of the vascular system, thereby simulating the flow state of blood at the valve.

[0044] Specifically, the ventricular simulator 1 acts as a power source to drive the flow medium in the pipeline to circulate by simulating the contraction and relaxation of the heart, while the atrial simulator 2 is responsible for storing and adjusting the amount of the flow medium to simulate the blood storage function of the atrium during the cardiac cycle.

[0045] The vascular damping simulator 5 provides necessary resistance for the flow medium by adjusting its internal structure or medium, simulating the blood flow resistance characteristics in the real vascular system; while the vascular compliance simulator 4 can simulate the expansion and contraction of blood vessels under different pressures, providing dynamic pulse pressure changes for the flow medium, further improving the accuracy of the test.

[0046] The highly transparent and compliant valve test chamber 3 is made of highly transparent and compliant materials such as highly transparent silicone. It not only has high transparency, which facilitates the high-speed camera 6 to capture particle images during the valve opening and closing process, but also has good compliance and can more realistically simulate the interaction between the valve and surrounding tissues.

[0047] The laser generator 7 emits laser light into the high-transparency compliance valve test cavity 3 to illuminate the tracer particles, allowing the high-speed camera 6 to capture particle images.

[0048] The high-speed camera 6 takes particle images after laser irradiation at a very high frame rate. These particle images record the pulsation and smoothness of the flow medium behind the valve during the opening and closing process of the artificial heart valve implant. Subsequently, the high-speed camera 6 uploads the captured particle images to the computer for subsequent processing and analysis. Through image processing technology and fluid mechanics analysis software, researchers can visualize the pulsating flow field of the heart valve. Specifically, the present application uses digital particle image velocimetry (DPIV) to visualize the pulsating flow field of the heart valve, thereby quantitatively analyzing the thrombosis and potential hemolysis risks after the heart valve is implanted in the expected position. The digital particle image velocimetry technology realizes the full flow field detection of the measured fluid under complex environment by using sequence images, image difference target detection, moving target tracking and other processing. The basic principle of DPIV technology is to spread a large number of tracer particles that are different from the color of the fluid medium and follow the type in the flow field, use plane light to illuminate these flowing particles, and take pictures of the measured flow field continuously. By analyzing these particle images, we can calculate the distance the particles move within a certain time interval, and thus find out the velocity of the particles at their locations.

[0049] exist Figure 1In the system shown, a test system consisting of a ventricular simulator, an atrial simulator, a high-transparency compliance valve test chamber, a vascular compliance simulator, a vascular damping simulator, a high-speed camera and a laser generator is constructed; in the test system, the ventricular simulator, the atrial simulator, the high-transparency compliance valve test chamber, the vascular compliance simulator and the vascular damping simulator are interconnected through pipelines to form a circulation loop, and an artificial heart valve implant is placed in the high-transparency compliance valve test chamber. During the test, the circulation loop simulates the blood flow environment of the artificial heart valve implant in the human body through the ventricular simulator, the atrial simulator, the vascular damper, the vascular compliance simulator and the high-transparency compliance valve test chamber, so as to provide accurate data support; the flow medium in the pipeline is added with a tracer particle suspension; the laser is irradiated to the high-transparency compliance valve test chamber by a laser generator to form a visualized flow field; the particle image behind the artificial heart valve implant after laser irradiation is obtained by a high-speed camera, and the particle image is uploaded to a computer to perform a visualized analysis of the heart valve pulsation flow field based on the digital particle image velocimetry technology. By analyzing the particle images captured by a high-speed camera using digital particle image velocimetry technology, various parameters in the flow field can be calculated, thereby quantitatively analyzing the risk of thrombosis and potential hemolysis after the heart valve is implanted in the intended site.

[0050] In some implementations of the embodiments of the present application, in order to enhance the visualization of the flow, transparent organic glass is used to simulate the various organs in the circulatory loop.

[0051] In some implementations of the embodiments of the present application, the artificial heart valve implant is one of an artificial aortic valve, an artificial pulmonary valve, an artificial mitral valve, and an artificial tricuspid valve. It can be seen that the artificial heart valve implant test system proposed in the present application has a high degree of flexibility and versatility, and can test the above four types of heart valves. In addition, the system adopts a modular design, and can customize the test cavity close to the clinical anatomical structure for valves in different release positions to meet standard requirements.

[0052] It is understandable that the heart's blood circulation system consists of two major parts: systemic circulation and pulmonary circulation. The heart valves and the order in which blood flows through are different in different circulation paths. In the systemic circulation, blood flows through the left atrium, mitral valve, left ventricle, aortic valve to the aorta in sequence; while in the pulmonary circulation, blood flows through the right atrium, tricuspid valve, right ventricle, pulmonary valve to the pulmonary artery in sequence. Therefore, when testing different types of artificial heart valves, it is necessary to flexibly adjust the connection order of each component in the test system according to the actual position and function of the valve to ensure the accuracy and effectiveness of the test.

[0053] like Figure 2As shown, when the test object is an artificial aortic valve or an artificial pulmonary valve, considering that these two valves are located at the outlets of the systemic circulation and the pulmonary circulation respectively, the circulation loop of the test system is designed to be connected in sequence with the atrial simulator 2, the ventricular simulator 1, and the high-transparency compliance valve test chamber 3. In this configuration, the simulated blood in the pipeline will flow through the atrial simulator 2 in sequence to simulate the atrial contraction and discharge process, then enter the ventricular simulator 1 to simulate ventricular contraction and pressurization, and then pass through the artificial heart valve in the high-transparency compliance valve test chamber 3 to evaluate its performance.

[0054] On the other hand, Figure 3 As shown, when the test object is an artificial mitral valve or an artificial tricuspid valve, since these two valves are located between the left ventricle and the left atrium, and between the right ventricle and the right atrium, respectively, the circulation loop of the test system needs to be adjusted so that the atrial simulator 2, the highly transparent and compliant valve test chamber 3, and the ventricular simulator 1 are connected in sequence. In this mode, the simulated blood first enters the atrial simulator 2, and then flows through the artificial heart valve in the highly transparent and compliant valve test chamber 3 and enters the ventricular simulator 1 to simulate the opening and closing state of the valve during ventricular filling, thereby evaluating its performance.

[0055] It should be noted that the present application does not limit the specific connection order of the vascular compliance simulator 4 and the vascular damping simulator 5. When the artificial heart valve implant is an artificial aortic valve or an artificial pulmonary valve, it can be set at any position between the atrial simulator 2 and the high-transparency compliance valve in the circulation loop according to the medium flow direction. When the artificial heart valve implant is an artificial mitral valve or an artificial tricuspid valve, it can be set at any position between the atrial simulator 2 and the ventricular simulator 1 in the circulation loop according to the medium flow direction.

[0056] In addition, given the significant differences in the anatomical positions and structural morphologies of the aortic valve, mitral valve, tricuspid valve, and pulmonary valve in the heart, this difference will affect the corresponding design and processing strategies. Figure 4 As shown, in the embodiment of the present application, in order to further improve the accuracy of the test, the left-hand illustrated model is used as the basis for designing and processing tooling for the aortic valve and the pulmonary valve to ensure that the tooling can adapt to their specific anatomical characteristics. For the mitral valve and the tricuspid valve, the right-hand illustrated model is used to customize the design and processing tooling to accurately meet their processing requirements, thereby comprehensively covering and optimizing the processing process of all key heart valves.

[0057] In some implementations of the present application, the high-speed camera 6 uses a dual-frame mode to acquire particle images to capture detailed changes in high-speed dynamic processes. Specifically, the camera not only takes pictures continuously, but also generates a pair of particle images each time it takes pictures. The two images are closely related and together constitute a particle image pair, which serves as a basic unit for time series analysis, thereby enhancing the ability to capture small changes.

[0058] In addition, in order to achieve accurate time synchronization and data acquisition, the synchronizer controls the emission frequency of the laser to be consistent with the acquisition frequency of the high-speed camera 6, and obtains a series of particle image pairs about the time series. Specifically, in this embodiment, the laser generator 7 and the high-speed camera 6 are directly connected to the same computer, and the computer is used as a synchronizer. The emission frequency of the laser pulse and the image acquisition frequency of the high-speed camera 6 are accurately synchronized to 15Hz by the synchronizer. Moreover, in the dual-frame mode, the camera is set to retain a time interval of 0.2ms between each pair of particle images to capture the key moments of the artificial heart valve during the opening and closing process, including the changes in its spatial position. By continuously shooting this series of particle image pairs, the spatial average of the valve at multiple time points can be accurately obtained to ensure the accuracy of the test results.

[0059] In some implementations of the present application, the ventricular simulator 1 uses a high-power voice coil motor as its core power source, which ensures that the system can output strong power to drive the flowing medium in the pipeline to circulate, while giving the ventricular simulator 1 a high degree of adjustment flexibility.

[0060] In view of the adjustable output curve of the high-power voice coil motor, its output power can be precisely controlled according to preset parameters or real-time feedback, so as to achieve fine adjustment of the pressure of the flowing medium in the pipeline and the cardiac output. According to actual needs, the heart activity from normal heart function to various pathological conditions can be simulated, so as to simulate the working conditions of the heart under different physiological conditions. It can be seen that through the setting of high-power voice coil motors, the test system can more realistically simulate the clinical conditions of patients from different populations. Whether it is the strong heart of a young and middle-aged person, the weak heart of an elderly person, or the heart of a patient with various heart diseases, their unique physiological characteristics can be simulated by adjusting the output curve of the motor. This provides a test environment that is closer to clinical practice for the performance evaluation of heart valve implants, thereby ensuring the accuracy and reliability of the test results.

[0061] In some implementations of the embodiments of the present application, the concentration of the tracer particles directly affects the accuracy of the measurement results. If the particle concentration is too high, it may have a significant impact on the flow itself, leading to two-phase flow problems; if the particle concentration is too low, there will not be enough particle pairs in each interpretation area, thus affecting the accuracy of the statistical analysis. Therefore, choosing a suitable tracer particle concentration is the key to ensuring measurement accuracy. In this regard, during the test process of the embodiments of the present application, after waiting for the pulsating flow field to reach a stable state, the concentration of the tracer particle suspension added to the flow medium in the tube is 0.25%. It should be noted that the choice of this concentration is the optimal value obtained by the inventor after repeated experiments and optimization. It can avoid a significant impact on the flow itself while ensuring that there are enough particle pairs in each interpretation area, and will neither introduce too many two-phase flow problems nor affect the accuracy of the measurement results due to insufficient number of particles.

[0062] In some implementations of the embodiments of the present application, the tracer particle suspension uses hollow glass beads as tracer particles. The hollow glass beads can not only effectively reflect the specific wavelength of the laser beam, ensuring the generation of clear and bright particle images under laser irradiation, but also have good followability, allowing the particles to closely follow the motion trajectory of the flowing medium, thereby accurately reflecting the flow field information.

[0063] Below, the application method of the system provided by this application is described in combination with actual application scenarios:

[0064] First, the system can be divided into two parts: the circulation loop system and the measurement system. The circulation loop system includes hardware such as a ventricular simulator 1, an atrial simulator 2, a high-transparency compliance valve test chamber 3, a vascular compliance simulator 4, a vascular damping simulator 5, a high-speed camera 6, and a laser generator 7, and pulsating flow performance test software. The hardware part can achieve normal human pressure, cardiac output, temperature and other regulation and control under software control. The measurement system includes hardware such as a laser generator 7, a high-speed camera 6, a synchronizer, and a data acquisition and analysis system developed based on the laboratory virtual instrument engineering platform Labview, which can record the particle velocity field in multiple valve opening and closing cycles, and automatically calculate the particle velocity field and shear field of the entire shooting area.

[0065] For each group of artificial heart valve tests, the cardiac output Q and the system pressure range are changed by adjusting the amplitude of the drive motor in the ventricular simulator 1, the high-transparency compliance valve test chamber 3 and the vascular damping simulator 5 to verify the performance of the valve under various flow rate conditions, for example, Q = 2.0, 3.5, 5.0, 7.0 L / min.

[0066] After each pulsating condition is adjusted to be stable, add a suitable concentration of tracer particle suspension, and then adjust the position of the laser emitter through the bracket so that the laser plane is accurately irradiated in the research area to ensure that the tracer particle image effect is clear. The emission wavelength of the laser is 532nm and the pulse frequency is 15Hz. In order for the particle image to effectively reflect the flow field information, the selected tracer particles need to effectively reflect the laser beam wavelength and have good followability. Therefore, hollow glass beads with a particle size of 5 to 20μm are selected as tracers.

[0067] After the laser is adjusted, the laser pulse frequency and camera acquisition frequency are synchronized to 15Hz through the synchronizer LaVison PTU X. The camera uses the dual-frame mode to record the time series with the particle image pair as the basic unit, and the time interval between the two images in each image unit is set to 0.2ms. Then the position of the camera is adjusted through the camera tripod to ensure that the shooting range can cover the expected analysis area. Figure 5 shown.

[0068] The flow field is visualized and analyzed in Matrix Lab MATLAB. Before analyzing the image results, the data units need to be converted. In the embodiment of the present application, the high-speed camera frequency acquisition and laser emission frequency are 15 Hz, the interval between two consecutive frames for calculating the flow field is 0.2 ms, and the image resolution is 2360×1776 pixels. 2 , it is necessary to deduce and calculate the appropriate object-image ratio. At the same time, it is necessary to ensure that the displacement of the tracer particles between every two frames is controlled within the range of 1 / 4 to 1 / 3 of the window size to ensure the reliability of the analysis data.

[0069] like Figure 6 As shown, T1 is the position where the valve begins to open, T2 is the position where the valve opens with the maximum flow rate, T3 is the position where the valve closes, and T4 is the position where the valve is completely closed. The arrow indicates the flow direction. The evaluation includes measurements at multiple characteristic moments in a cardiac cycle, including the velocity field in the normal plane of the heart valve axis during systole and diastole, and the shear stress field and vorticity field are derived based on the calculated velocity field.

[0070] Excessive shear stress may damage red blood cells, causing hemolysis or damaging the endothelium of the blood vessel wall; abnormal shear stress can also change the biological behavior of certain cells, such as activating platelets in the blood and leading to the formation of blood clots; reflux and separation flow in blood flow can cause damage to the blood, the reflux area and the eddy flow area. Activated platelets and lipids and other substances in this area are prone to aggregation. This situation usually occurs behind high shear stress and is prone to plaque aggregation in the flow field.

[0071] See also Figure 7, this application uses a self-developed software system to directly deduce and calculate the shear field of velocity particles in the flow field, so that the shear force distribution diagram in the post-valvular flow field can be intuitively seen, and thrombosis and potential hemolysis risk analysis can be evaluated. It can be concluded from the shear stress field distribution that the shear stress value is within the safe range of 1Pa to 7Pa. When the lower heart valve is opened to the maximum, the shear stress also reaches its maximum. When the heart valve begins to close, the velocity gradually decreases, and the velocity gradient also decreases at the same time. When the heart valve is completely closed, the shear stress is close to zero.

[0072] See also Figure 8 As shown, the embodiment of the present application also provides a method for testing an artificial heart valve implant, the method comprising:

[0073] S801: An artificial heart valve implant is placed in a high-transparency compliance test chamber, and a blood flow environment in a human body is simulated in the high-transparency compliance test chamber.

[0074] In an embodiment of the present application, the artificial heart valve implant to be tested is first installed in a highly transparent and well-compliant test chamber; then, a blood flow environment close to the real one in the human body is accurately simulated in the test chamber to ensure the accuracy and reliability of the test.

[0075] S802: irradiating laser into the high-transparency compliance test cavity, and the flowing medium in the high-transparency compliance test cavity is added with tracer particle suspension.

[0076] In the embodiment of the present application, a laser beam is irradiated into the set high-transparency compliance test cavity by a laser generator. At the same time, an appropriate amount of tracer particle suspension is injected into the flowing medium. The tracer particles need to have good laser reflectivity and tracking properties to ensure that they can accurately reflect the changes in the flow field.

[0077] S803: Acquire a particle image behind the artificial heart valve implant after laser irradiation, and generate an analysis view of the heart valve pulsating flow field based on the particle image.

[0078] In the embodiment of the present application, a high-speed camera is used to capture particle images behind the artificial heart valve implant under laser irradiation. The particle images record the trajectory of the tracer particles flowing with the fluid, reflecting the effect of the heart valve on blood flow. Subsequently, the collected particle images are deeply analyzed through digital particle image velocimetry technology to generate an analysis view of the heart valve pulsating flow field, providing intuitive data support for evaluating the performance of the heart valve and achieving quantitative analysis.

[0079] In some implementations of the embodiments of the present application, the analysis view is a particle velocity field analysis view, wherein the particle velocity field analysis view is used to describe the particle velocity distribution in the normal plane of the heart valve axis at multiple contraction moments and multiple diastole moments in at least one cardiac cycle.

[0080] Among them, the particle velocity field analysis view is used to describe the movement speed and direction of particles in the fluid medium, so as to study the dynamic characteristics of blood flow in the heart.

[0081] Specifically, the cardiac cycle refers to the entire process of the heart completing one contraction and relaxation, which can be one or more cycles, in order to more comprehensively observe the performance of the heart at different stages. The particle velocity distribution in the normal plane of the heart valve axis refers to the velocity distribution of particles in the flowing medium in the normal direction of the plane where the heart valve axis is located. It can be used to analyze the changes in blood flow velocity near the heart valve when it is opened and closed, which is useful for evaluating the functional status of the heart valve and diagnosing related diseases.

[0082] In some implementations of the embodiments of the present application, the method further includes the following steps:

[0083] Based on the particle velocity distribution in the normal plane of the heart valve axis at multiple contraction moments and multiple relaxation moments in at least one cardiac cycle, a particle shear stress field analysis view is generated, wherein the particle shear stress field analysis view is used to describe the particle shear stress distribution in the normal plane of the heart valve axis at multiple contraction moments and multiple relaxation moments in at least one cardiac cycle.

[0084] Shear stress is a concept in fluid dynamics, which is used to describe the force generated by the velocity difference inside the fluid or between the fluid and the solid boundary. The embodiment of the present application visualizes the shear stress distribution behind the flap by generating a particle shear stress field analysis view.

[0085] Finally, it should be noted that, in the embodiments of the present application, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements includes not only those elements, but also includes other elements that are not clearly listed, or also includes elements inherent to such process, method, article or equipment. In the absence of more restrictions, the elements limited by the statement "comprise one..." do not exclude the presence of other identical elements in the process, method, article or equipment including the elements.

[0086] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A testing system for an artificial heart valve implant, characterized in that: The system comprises: a ventricular simulator, an atrial simulator, a highly transparent and compliant valve test chamber, a vascular compliance simulator, a vascular damping simulator, a high-speed camera and a laser generator; The ventricle simulator, the atrial simulator, the high-transparency compliance valve test chamber, the vascular compliance simulator, and the vascular damping simulator are interconnected through pipelines to form a circulation loop. An artificial heart valve implant is arranged in the high-transparency compliance valve test chamber. During testing, the circulation loop simulates the blood flow environment of the artificial heart valve implant in the human body; The ventricular simulator is used to provide power for the flowing medium in the pipeline; wherein the flowing medium in the pipeline is added with a tracer particle suspension; The atrial simulator is used to store the flow medium in the pipeline; The vascular damper is used to provide resistance to the flow medium in the pipeline; The vascular compliance simulator is used to provide pulse pressure for the flowing medium in the pipeline; The highly transparent and compliant valve test cavity is used to provide a shooting window for the high-speed camera; The laser generator is used to irradiate laser light to the high-transparency compliance valve test cavity; The high-speed camera is used to obtain particle images behind the artificial heart valve implant after laser irradiation, and upload the particle images to a computer for visualization analysis of the heart valve pulsation flow field based on digital particle image velocimetry technology.

2. The system according to claim 1, characterized in that The artificial heart valve implant is one of an artificial aortic valve, an artificial pulmonary valve, an artificial mitral valve and an artificial tricuspid valve.

3. The system according to claim 2, characterized in that When the artificial heart valve implant is the artificial aortic valve or the artificial pulmonary valve, in the circulation loop, the atrial simulator, the ventricular simulator, and the high-transparency compliance valve test chamber are connected in sequence.

4. The system according to claim 2, characterized in that When the artificial heart valve implant is the artificial mitral valve or the artificial tricuspid valve, in the circulation loop, the atrial simulator, the high-transparency compliance valve test chamber and the ventricular simulator are connected in sequence.

5. The system according to claim 1, characterized in that The high-speed camera uses a double-frame mode to acquire the particle image.

6. The system according to claim 1, characterized in that The ventricular simulator specifically regulates pressure and cardiac output through a high-power voice coil motor to provide power for the flowing medium in the pipeline.

7. The system according to claim 1, characterized in that The tracer particle suspension uses hollow glass beads as tracer particles.

8. A method for testing an artificial heart valve implant, characterized in that: The method comprises: An artificial heart valve implant is arranged in a highly transparent and compliant test chamber, and a blood flow environment in a human body is simulated in the highly transparent and compliant test chamber; irradiating a laser into a high-transparency compliance test cavity, wherein a tracer particle suspension is added to a flowing medium in the high-transparency compliance test cavity; A particle image behind the artificial heart valve implant after laser irradiation is acquired, and an analysis view of the heart valve pulsating flow field is generated based on the particle image.

9. The method according to claim 8, characterized in that The analysis view is a particle velocity field analysis view, wherein the particle velocity field analysis view is used to describe the particle velocity distribution in the normal plane of the heart valve axis at multiple contraction moments and multiple relaxation moments in at least one cardiac cycle.

10. The method according to claim 9, characterized in that The method further comprises: Based on the particle velocity distribution in the normal plane of the heart valve axis at multiple contraction moments and multiple relaxation moments in at least one cardiac cycle, a particle shear stress field analysis view is generated, wherein the particle shear stress field analysis view is used to describe the particle shear stress distribution in the normal plane of the heart valve axis at multiple contraction moments and multiple relaxation moments in at least one cardiac cycle.

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