Aortic valve and ascending aorta in-vitro testing and evaluating device

Abstract

The invention provides an aortic valve and ascending aorta in-vitro testing device. The aortic valve and ascending aorta in-vitro testing device comprises a cavity system, a driving system, a loop system, a cavity auxiliary system, a control system and a particle image velocity measurement system. According to the device, a 1: 1 personalized aortic valve and ascending aorta vessel model is constructed based on a medical image of a patient, and a personalized hemodynamic environment is truly simulated through closed-loop pulsating flow circulation. Complex functional parameters such as blood flow velocity, pressure intensity, wall shear force and relative particle residence time can be rapidly and quantitatively obtained, and the limitation that traditional images only provide morphological data and CFD simulation depends on ideal assumption is overcome. Meanwhile, the method can be used for individualized in-vitro testing of the artificial aortic valve, the performance of the artificial aortic valve in a specific anatomical structure is evaluated, and the accuracy of preoperative planning, postoperative prediction and instrument research and development is remarkably improved. The device has the advantages of being high in physiological reduction degree, high in testing efficiency, high in result repeatability and the like, and is suitable for precise cardiovascular diagnosis and treatment and evaluation of implanted interventional instruments.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of aortic valve and ascending aorta performance testing, and particularly relates to an aortic valve and ascending aorta in-vitro test evaluation device. BACKGROUND

[0002] The aortic valve is located between the left ventricle and the ascending aorta, and is normally composed of three leaflets to control the one-way flow of blood. Common lesions include aortic valve stenosis (not opening) and regurgitation (not closing tightly), which can be caused by congenital malformations, calcification or inflammation, etc. These lesions not only affect heart function, but also can cause the ascending aorta to dilate, become tumor-like, or even tear due to abnormal blood flow impact.

[0003] Currently, clinical evaluation of aortic valve and ascending aorta morphology, such as leaflet number, annulus diameter, vessel width, etc., is mainly relied on imaging techniques such as CT, MRI or ultrasound, and whether surgery is needed is determined in combination with simple mechanical parameters such as flow velocity and pressure difference. However, these methods cannot directly obtain complex hemodynamic indicators such as wall shear stress and blood flow residence time, which are closely related to disease progression. Although computer fluid simulation (CFD) can be used to estimate these complex parameters, simulation relies on multiple idealized assumptions, is time-consuming to calculate, and the results may deviate from the actual situation.

[0004] In terms of treatment, transcatheter implantation of artificial aortic valves has become an important means. Studies have shown that the same valve may perform significantly differently in different patients, and in an ideal model, the performance is good, but after actual implantation, deformation, leakage or early failure may occur. Therefore, the existing evaluation methods lack personalized mechanical characteristic analysis, and in-vitro test models are difficult to truly reflect the patient's in-vivo environment, which limits precise diagnosis and treatment and prediction of device effectiveness. SUMMARY

[0005] In view of the above shortcomings of the prior art, the purpose of the present application is to provide an aortic valve and ascending aorta in-vitro test evaluation device to solve the problem that the existing evaluation methods lack personalized mechanical characteristic analysis, in-vitro test models are difficult to truly reflect the patient's in-vivo environment, and precise diagnosis and treatment and prediction of device effectiveness are limited.

[0006] To achieve the above object and other related objects, the present application provides an aortic valve and ascending aorta in-vitro test evaluation device, comprising: a chamber system, a driving system, a chamber auxiliary system, a loop system, a control system and a particle image velocimetry system.

[0007] The chamber system is used to simulate the blood flow path, comprising:

[0008] A left ventricle system is used to simulate left ventricular contraction to drive fluid.

[0009] An aortic valve and ascending aorta vascular system, the internal cavity structure of which is manufactured by reverse modeling according to specific medical image data, and is consistent with the actual aortic valve maximum opening shape, aortic sinus geometry and ascending aorta direction;

[0010] An ascending aorta liquid buffer cavity connected with the cavity outlet end of the aortic valve and ascending aorta vascular system, used for temporarily storing the liquid flowing out from the aortic valve and ascending aorta vascular system;

[0011] A left atrium system and a corresponding liquid buffer cavity, the left atrium system being communicated with the left ventricle system for receiving the backflow liquid and forming a closed circulation;

[0012] The driving system is connected with the left ventricle system for providing a periodic pulsation driving force to simulate the heart beat;

[0013] The loop system connects the outlet of the aortic valve and ascending aorta vascular system with the left atrium liquid buffer cavity, forms a closed circulation loop of the test fluid, and contains components for adjusting the fluid temperature and peripheral resistance;

[0014] The cavity auxiliary system includes an aortic sinus compliance cavity communicated with the aortic sinus area in the aortic valve and ascending aorta vascular system for simulating the physiological coronary compliance;

[0015] The control system is used for setting a target pressure or flow curve, and implementing closed-loop feedback control on the driving system based on the real-time collected pressure signal, so that the test point pressure dynamically tracks the preset target;

[0016] The particle image velocimetry system is configured in the optical visible area of the personalized aortic valve and ascending aorta vascular system, and is used for non-invasively acquiring the blood flow dynamics parameters such as fluid velocity field, wall shear stress and relative particle residence time.

[0017] In an embodiment of the present application, the left ventricle system includes:

[0018] An outer cavity, the bottom of which is provided with an outer cavity sealing valve and an inner cavity sealing valve, the outer cavity sealing valve being connected with the outer cavity, and the bottom of the outer cavity being further provided with an opening, the opening being connected with the driving system;

[0019] An inner cavity, which is arranged inside the outer cavity and has its bottom connected to the inner cavity sealing valve through a hose;

[0020] A diagonal beam cover, which is arranged at the top of the outer cavity and the inner cavity and is sealingly connected therewith, the diagonal beam cover being connected with the aortic valve and ascending aorta vascular system, the left atrium system respectively.

[0021] In one embodiment of the present application, the bevel cover has two bevels, a first bevel opening and a second bevel opening, which are respectively arranged in communication with the aortic valve and the ascending aorta blood vessel system, and the first bevel opening and the second bevel opening are in communication with the inner chamber.

[0022] In one embodiment of the present application, a detachable one-way valve is arranged at the first bevel opening and / or the second bevel opening, and the one-way valve is configured to allow fluid to flow only in one direction from the left ventricle to the ascending aorta or from the left atrium to the left ventricle.

[0023] In one embodiment of the present application, a flow meter is detachably arranged between the bevel having the first bevel opening and the aortic valve and the ascending aorta blood vessel system.

[0024] In one embodiment of the present application, the aortic valve and the ascending aorta blood vessel system comprise:

[0025] a chamber;

[0026] an aortic sinus compliance chamber connection port, one end of which is in communication with the aortic sinus part of the chamber, and the other end is connected to the chamber auxiliary system;

[0027] a liquid outlet, one end of which is in communication with the top of the chamber, and the other end is connected to the circuit system;

[0028] a sub-valve three-way valve interface and a supra-valve three-way valve interface, which are respectively in communication with the inlet and outlet of the chamber.

[0029] In one embodiment of the present application, the aortic valve and the ascending aorta blood vessel system are integrally formed by 3D printing.

[0030] In one embodiment of the present application, the aortic valve and the ascending aorta blood vessel system comprise a transparent shell and a chamber arranged in the inner chamber of the shell, the chamber wall of the chamber and the transparent shell are hollow structures, and the chamber wall is a flexible structure.

[0031] In one embodiment of the present application, the personalized aortic valve and the ascending aorta blood vessel system are prepared by the following steps:

[0032] Obtaining CT, MRI or ultrasound images of the patient at the end of the cardiac systole;

[0033] Segmenting the three-dimensional profile of the aortic root, aortic sinus, valve leaflet and ascending aorta;

[0034] After removing the significantly calcified area, reverse modeling is performed to generate an STL / CAD model;

[0035] A physical model with an internal cavity is manufactured by 3D printing, reverse molding or machining.

[0036] In one embodiment of the present application, the control system integrates a pressure feedback adjustment subsystem, which sets a high-speed pressure sensor at the near-cusp, middle segment of ascending aorta or aortic sinus, and dynamically adjusts the driving system based on real-time pressure signals using a PID control algorithm, so that the measured pressure waveform tracks the preset clinical target pressure curve.

[0037] The aortic valve and the in-vitro testing device for the ascending aorta have the following beneficial effects:

[0038] The in-vitro testing device can output personalized mechanical characteristic parameters, and can output complex mechanical characteristic parameters based on the personalized physiological anatomical characteristics (such as the aortic valve and the ascending aorta blood vessel morphology) of the patient. These parameters include but are not limited to wall shear stress, relative particle residence time, and the like, which are helpful for more accurately evaluating the physiological state of the patient.

[0039] The device can output diversified parameters, and can not only provide morphological parameters such as diameter and area, and simple mechanical parameters such as flow rate and pressure, but also output complex mechanical parameters based on the individualization of the patient, such as wall shear stress and relative particle residence time. This multi-dimensional data output provides strong support for comprehensive evaluation of cardiovascular health.

[0040] The device can reduce calculation errors, and compared with the traditional virtual simulation calculation method, the device reduces calculation errors caused by mathematical assumptions through an actual physical model, and ensures that the test parameter values are more accurate. In addition, since complex computer simulation is not required, the device significantly reduces the time consumption and the requirement for computer performance.

[0041] The in-vitro testing device can also be used for individualized in-vitro testing of artificial aortic valves. Compared with the traditional testing method based on a general idealized model, the device can output more accurate device performance evaluation results close to the actual situation of the patient. This makes preoperative planning more accurate, and is beneficial for device optimization design and customized personalized medical services.

[0042] The device can quickly and comprehensively output functional parameters, and can quickly output a variety of functional parameters based on the personalized physiological anatomical characteristics of different patients, including blood flow velocity, blood ejection angle, blood flow pressure, fluid wall shear stress, relative particle residence time, and the like. These parameters provide rich data support for clinicians, which is helpful for preoperative surgical planning, postoperative outcome prediction, and device optimization design.

[0043] It can assist personalized medical customization. Through detailed analysis of the personalized aortic valve and ascending aorta blood vessel morphology of the patient, the device can generate instrument performance evaluation results that fit the actual situation of the patient. This not only improves the success rate of surgery, but also provides a scientific basis for personalized medical customization, further promoting the development of precision medicine.

[0044] In summary, the aortic valve and ascending aorta in vitro testing device provided by the present application realizes in vitro testing of the aortic valve and ascending aorta blood vessel based on the personalized physiological and anatomical characteristics of different patients. It not only can quickly output diversified functional parameters, but also can perform individual in vitro testing on the artificial aortic valve, and output instrument performance evaluation results that are more in line with the actual situation of the patient. These characteristics greatly improve the accuracy and reliability of preoperative surgical planning, postoperative outcome prediction, instrument optimization design, and personalized medical customization.

[0045] Through the above technical effects, the present application not only solves many deficiencies in the prior art, but also provides strong technical support for the diagnosis, treatment planning and research and development of medical instruments of cardiovascular diseases. The modular design and flexible expansion also provide a broad space for future research and application. BRIEF DESCRIPTION OF DRAWINGS

[0046] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used for the embodiment description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0047] Figure 1 It is a schematic diagram of the aortic valve and ascending aorta in vitro testing device.

[0048] Figure 2 It is another angle schematic diagram of the aortic valve and ascending aorta in vitro testing device.

[0049] Figure 3 It is a schematic diagram of the chamber system structure.

[0050] Figure 4 It is a schematic diagram of the internal structure of the chamber system.

[0051] Figure 5 It is a front view sectional view of the chamber system.

[0052] Figure 6 It is a schematic diagram of the left ventricular system structure

[0053] Figure 7 It is an embodiment form of the one-way valve.

[0054] Figure 8 Another embodiment of a one-way valve.

[0055] Figure 9 A flow meter schematic.

[0056] Figure 10 Front view of a personalized aortic valve and ascending aorta vasculature.

[0057] Figure 11 Back view of a personalized aortic valve and ascending aorta vasculature.

[0058] Figure 12 Internal structure of a personalized aortic valve and ascending aorta vasculature.

[0059] Figure 13 Manufacturing process of a personalized aortic valve and ascending aorta vasculature.

[0060] Figure 14 An embodiment of a personalized aortic valve and ascending aorta vasculature.

[0061] Figure 15 Another embodiment of a personalized aortic valve and ascending aorta vasculature.

[0062] Figure 16 Ascending aorta liquid cache cavity structure schematic.

[0063] Figure 17 Internal structure of an ascending aorta liquid cache cavity.

[0064] Figure 18 Left atrium system and left atrium liquid cache cavity structure schematic.

[0065] Figure 19 Internal structure of a left atrium system and left atrium liquid cache cavity.

[0066] Figure 20 Drive system and power system schematic.

[0067] Figure 21 Chamber assist system, circuit system, and control system schematic.

[0068] Figure 22 Time-displacement-velocity curve embodiment for a pump according to actual pressure feedback setting.

[0069] Figure 23 Flowchart of a method for evaluating an aortic valve and an ascending aorta in vitro according to an embodiment of the present invention.

[0070] Figure 24A flowchart of an aortic valve and ascending aorta in vitro evaluation method provided in another embodiment of the present application. DETAILED DESCRIPTION

[0071] The advantages and effects of the present application can be easily understood by those skilled in the art from the description. The present application can also be implemented or applied in different specific embodiments, and various modifications or changes can be made to the details in the description without departing from the spirit of the present application.

[0072] It should be noted that the diagrams provided in the embodiments only schematically illustrate the basic concepts of the present application, and only the relevant components in the present application are shown in the diagrams, not the number, shape and size of the components when actually implemented. The actual implementation of each component can be arbitrarily changed in terms of type, number and proportion, and the component layout can also be more complex.

[0073] As shown in Figure 1 and Figure 2 The present application provides an aortic valve and ascending aorta in vitro test evaluation device, which comprises a chamber system 11, a driving system 12, a power system 13, a chamber auxiliary system 14, a loop system 15, a control system 16 and a particle image velocimetry system 17. The device realizes accurate acquisition of personalized hemodynamic parameters by constructing a physical model highly consistent with the patient's anatomical structure, combining closed-loop pressure feedback control and high-precision flow field measurement.

[0074] When the device is running, the driving system 12 periodically squeezes the left ventricular system 111 to push the test fluid (such as glycerol-water mixture simulating blood) to flow through the personalized aortic valve and ascending aorta vascular system 113, and then through the ascending aorta liquid buffer chamber 114, the loop system 15 and the left atrial liquid buffer chamber 116 to form a closed loop. The control system 16 adjusts the driving strength in real time according to the preset clinical pressure curve to ensure that the pressure at the key measurement point dynamically matches the target value; at the same time, the particle image velocimetry system 17 synchronously collects flow field data for calculating complex hemodynamic indexes such as wall shear stress, oscillatory shear index and relative particle residence time.

[0075] The chamber system 11 is a core component system for simulating the complete blood flow path that "the blood in the left ventricle is squeezed by the heart and then ejected from the abnormal aortic valve, flows through the diseased ascending aorta, recirculates to the left atrium, passes through the mitral valve, and finally returns to the left ventricle", and is also a key carrier for representing the complex mechanical characteristics corresponding to the patient's personalized aortic valve and ascending aorta vascular morphology.

[0076] As shown in Figure 3As shown, the 11-chamber system comprises: a left ventricle system 111, a flow meter 112, a personalized aortic valve and ascending aorta blood vessel system 113, an ascending aorta liquid buffer chamber 114, a left atrium system 115 and a left atrium liquid buffer chamber 116.

[0077] Figure 4 FIG. 1 is a schematic diagram of the internal structure of the chamber system 11, Figure 5 FIG. 2 is a front view of the chamber system 11. As shown, Figure 4 As shown, Figure 5 It can be seen that the internal cavities of each adjacent component in the chamber system 11 are mutually through, and the test liquid can continuously flow in the entire through flow channel. The components are fixed by suitable mechanical connection methods such as welding, threaded connection, buckling, and are assisted by sealing means such as gasket sealing and coating sealant to ensure that the system does not leak during operation.

[0078] The left ventricle system 111 is used to simulate the periodic contraction movement of the left ventricle and to apply pulsating extrusion pressure to the liquid in the chamber, thereby driving the fluid flow. The left ventricle system 111 comprises: an inner chamber 1111, an outer chamber 1112, a sloping beam cover 1113, an outer chamber sealing valve 1114, an inner chamber sealing valve 1115 and an inner chamber three-way valve 1116.

[0079] The inner chamber 1111 is a U-shaped open chamber made of transparent film material, and the bottom thereof is connected to the inner chamber sealing valve 1115 by a hose. As an optional solution, the transparent film material is preferably high-transmittance medical silicone, so as to take into account flexibility and optical visibility.

[0080] The outer chamber 1112 is made of transparent hard material and has an open cavity structure for wrapping and containing the inner chamber 1111. The bottom thereof is provided with the outer chamber sealing valve 1114 and the inner chamber sealing valve 1115. The outer chamber sealing valve 1114 directly communicates with the outer chamber 1112 body, and the inner chamber sealing valve 1115 communicates with the inner chamber 1111 through a hose. As an optional solution, the transparent hard material can be glass, acrylic or similar materials with good optical properties and high mechanical strength.

[0081] The sloping beam cover 1113 is made of transparent hard material and has a whole "eave" shape, and the included angle a° is formed between the bottom plane and the two top inclined planes. Through openings are respectively provided on the bottom plane and the two top inclined planes. The side wall of the sloping beam cover 1113 is provided with the inner chamber three-way valve 1116 for connecting a pressure sensor or an exhaust device.

[0082] As shown, Figure 5 As shown, Figure 6As shown, the top opening of the inner chamber 1111, the top opening of the outer chamber 1112 and the bottom opening of the inclined beam cover 1113 are completely consistent in size and tightly fitted through a sealed connection. Under this connection relationship, the inner chamber 1111 and the inner cavity of the inclined beam cover 1113 are mutually penetrated, forming a main blood flow channel; while the outer chamber 1112 is independent of the channel and only serves as a driving medium cavity, not being in communication with the inner chamber 1111 or the inner cavity of the inclined beam cover 1113.

[0083] The opening at the bottom of the outer chamber 1112 is connected with the driving system 12, for receiving the pressure input of the driving medium (such as water or silicone oil), thereby indirectly extruding the inner chamber 1111 to simulate the ventricular contraction.

[0084] The top of the inclined beam cover 1113 is provided with two inclined openings: the first inclined opening 11131 is connected with the flow meter 112, for guiding the outflow liquid to enter the aortic passage; and the second inclined opening 11132 is connected with the left atrium system 115, for guiding the diastolic regurgitant liquid to return to the left atrium side.

[0085] As a preferred embodiment, the included angle a° of the inclined beam cover 1113 should be set according to the actual spatial included angle between the aortic valve plane, the mitral valve plane and the long axis of the left ventricle in the medical images of the patient, to truly restore the spatial geometric relationship between the blood flow emission direction and the regurgitant path.

[0086] Further, the size of the first inclined opening 11131 should be customized according to the aortic annulus diameter or effective opening area in the images of the patient; and the size of the second inclined opening 11132 should be set according to the mitral annulus size, so as to match the individualized anatomical characteristics.

[0087] In addition, the diameters of the opening of the inner chamber 1111, the top opening of the outer chamber 1112 and the bottom opening of the inclined beam cover 1113 are preferably not less than 10 mm, so as to avoid excessive flow resistance affecting the physiological authenticity.

[0088] The overall size of the outer chamber 1112 also needs to meet the driving stroke requirement, and the length is preferably not less than 250 mm, the width is preferably not less than 150 mm, and the height is preferably not less than 200 mm.

[0089] In one embodiment, a one-way valve can be installed at the first inclined opening 11131 and / or the second inclined opening 11132. The one-way valve is designed to allow liquid to flow only from the inner chamber 1111 to the flow meter 112, or from the left atrium system 115 to the inner chamber 1111, while the reverse flow is blocked, thereby simulating the one-way conduction function of the valve. The one-way valve adopts a detachable structure, and whether to be installed can be flexibly selected according to the specific test purpose. Preferably, the outer frame of the one-way valve is made of soft silicone material, so as to achieve good interface sealing when being installed, preventing bypass leakage.

[0090] Figure 7 An embodiment of a one-way valve is shown: its inner baffle elastically pops outward to open under the impact of liquid on one side, and automatically rebounds to close when the pressure difference on both sides disappears; if it is pressed in the opposite direction, the inner baffle is blocked and cannot open.

[0091] Figure 8 Another implementation is shown: the inner baffle rotates around the axis to open under unilateral pressure, and closes by elastic reset after the pressure difference is balanced; it cannot rotate to open under reverse pressure due to structural limitations.

[0092] like Figure 9 As shown, the flow meter 112 is a transitional assembly with an internal cylindrical tube for connecting the left ventricular system 111 to the personalized aortic valve and ascending aortic vascular system 113. When test fluid flows through its internal tube, built-in sensors detect and output instantaneous flow data in real time.

[0093] It must be ensured that the diameter of the cylindrical pipe inside the flow meter 112 is equal to the diameter of the first oblique opening 11131, and that the two are reliably sealed during assembly using sealing rings, sealant, or other suitable methods to prevent leakage and ensure the continuity of the flow path.

[0094] In one embodiment, the sensor used in the flow meter 112 may be an ultrasonic flow sensor, an electromagnetic flow sensor, or other flow sensing devices suitable for simulating blood flow measurement. The specific type can be selected according to actual needs such as test accuracy, fluid conductivity, and optical transparency.

[0095] Furthermore, the external structural shape of the flow meter 112 is not limited and can be designed as an "I" shape, cuboid, or other geometric form that facilitates installation and connection. The preferred connection method between it and adjacent components is threaded connection or snap-fit ​​connection to balance sealing performance and ease of assembly and disassembly.

[0096] In another embodiment, the flow meter 112 is a non-essential component. When real-time monitoring of flow parameters is not required during testing, it can be completely removed, and the left ventricular system 111 can be directly and sealed to the personalized aortic valve and ascending aortic vascular system 113 via threads, snaps, or other compatible interfaces, thereby simplifying the flow path structure and reducing system complexity.

[0097] The chamber design of the personalized aortic valve and ascending aortic vascular system 113 is completely consistent with the patient's actual aortic valve and ascending aortic vascular morphology. This system 113 is the main component for achieving a 1:1 mapping of the patient's actual blood flow state and for assessing the complex biomechanical characteristics of the patient's personalized aortic valve and ascending aortic vascular morphology.

[0098] Figure 10Front view of the personalized aortic valve and ascending aorta vascular system 113; Figure 11 Back view of the same; Figure 12 And the internal structure view is shown.

[0099] As shown in Figure 11 , Figure 12 and Figure 13 , in one embodiment of the personalized aortic valve and ascending aorta vascular system 113, although the outer shell shape can be in any suitable form, the internal chamber is strictly designed according to the patient's physiological anatomy, ensuring the true reproduction of fluid flow. The aortic valve and ascending aorta vascular system 113 includes: an aortic sinus compliance chamber connection port 1131, a liquid flow outlet 1132, a sub-valve three-way valve interface 1133, and a supra-valve three-way valve interface 1134. Among them, the aortic sinus compliance chamber connection port 1131 communicates with the aortic sinus area in the chamber and is connected to the chamber auxiliary system 14 through a hose to simulate the sinus coronary compliance under physiological conditions. The liquid flow outlet 1132 is located at the top of the chamber (i.e. the top of the ascending aorta) and is connected to the circuit system 15 through a hose. The sub-valve three-way valve interface 1133 and the supra-valve three-way valve interface 1134 correspond to the chamber inlet and outlet positions, respectively, for the convenience of connecting pressure sensors or other monitoring devices.

[0100] The personalized aortic valve and ascending aorta vascular system 113 can be connected and installed with adjacent components through suitable means such as threads or buckles. In order to ensure the continuity and sealing of the flow channel, the inlet diameter of the system 113 should match the internal cylindrical pipe diameter (or the diameter of the first beveled opening 11131) of the flow meter 112, and necessary sealing measures should be taken when connecting.

[0101] Figure 13 The manufacturing process of the personalized aortic valve and ascending aorta vascular system 113 is shown in detail:

[0102] Step 1: Obtain CT, MRI or ultrasound images of the patient at the end of systole; for example, use medical imaging equipment (such as CT, MRI or ultrasound) to obtain images of the patient's physiological characteristics at the end of systole (i.e. when the aortic valve is fully open).

[0103] Step 2: Segment the three-dimensional contours of the aortic root, aortic sinus, leaflets and ascending aorta;

[0104] Step 3: After removing the significantly calcified area, reverse modeling is performed to generate an STL / CAD model; for example, use computer reverse modeling technology to reconstruct a personalized aortic valve and ascending aorta vascular three-dimensional model, paying special attention to the details of the valve opening (if there is significant calcification, it should be removed in the model) and using computer-aided design to trim and smooth the three-dimensional model.

[0105] Step4: Manufacture the physical model with a hollow cavity inside by 3D printing, inverse molding or machining. For example, use rapid 3D printing technology to directly manufacture the personalized aortic valve and ascending aorta blood vessel system 113, and the model area is the hollow cavity area.

[0106] Thanks to the high development of medical image scanning, computer modeling and 3D printing technology, the personalized aortic valve and ascending aorta blood vessel system 113 can accurately replicate key anatomical features of the patient's valve maximum opening area, shape, calcification area and ascending aorta bending shape, etc. At present, based on these advanced technologies, the processing of the system can be completed within one hour, and quickly assembled with other components.

[0107] As an optional solution, the personalized aortic valve and ascending aorta blood vessel system 113 can also be manufactured by using various methods such as inverse molding, machining, etc. alone or in combination. In particular, it is considered that the design of the transparent shell should be reasonably set according to the aortic valve and ascending aorta blood vessel shape in the actual image to ensure the structural stability of the entire system.

[0108] Figure 14 An embodiment is shown, in which the cavity shell is transparent and hard material, suitable for integrated 3D printing forming, with lower economic cost, time cost and technical difficulty. The hard cavity wall will not be deformed obviously due to fluid impact, which is beneficial to the subsequent analysis of fluid flow field, wall shear force and other mechanical parameters.

[0109] Figure 15 Another embodiment is shown, in which the cavity and the transparent shell are designed as a hollow, and the cavity wall is made of a thin layer of material, which can be soft (such as soft silicone) or hard. When using flexible material, the cavity wall will expand or rebound with fluid impact, which is closer to the real physiological environment, and helps to improve the accuracy of fluid flow field and wall shear force and other mechanical parameter evaluation.

[0110] In this embodiment, the ascending aorta liquid buffer cavity 114 is connected to the outlet end of the cavity of the personalized aortic valve and ascending aorta blood vessel system 113, for temporarily storing the test liquid flowing out of the personalized aortic valve and ascending aorta blood vessel system 113.

[0111] As shown in Figure 16 and Figure 17 , the ascending aorta liquid buffer cavity 114 mainly includes three components: a liquid storage cavity 1141, an observation bin 1142 and an ascending aorta liquid buffer cavity flow guide port 1143.

[0112] The liquid storage cavity 1141 is a hollow cavity, and its external shape can be designed into any suitable geometric shape according to the connection layout or overall device aesthetic requirements.

[0113] The observation chamber 1142 is a U-shaped transparent component inserted into the top of the fluid reservoir 1141. Its top is open, and its bottom is closed, achieving a sealed connection with the fluid reservoir 1141. Both the fluid reservoir 1141 and the observation chamber 1142 are made of transparent rigid materials (such as acrylic or medical-grade transparent resin). Operators can directly observe the fluid flow at the outlet of the personalized aortic valve and ascending aortic vascular system 113 in real time through the observation chamber 1142. A miniature camera can also be installed inside the observation chamber 1142 to record the dynamic behavior of the fluid after it exits the personalized aortic valve and ascending aortic vascular system 113.

[0114] The ascending aortic fluid buffer chamber inlet 1143 is directly connected to the fluid storage chamber 1141. When the fluid level in the fluid storage chamber 1141 reaches the height of the inlet 1143, the excess fluid will flow into the connecting pipe through the inlet 1143 and be transported to the left atrial fluid buffer chamber 116 through the circuit system 15, thereby completing the closed loop.

[0115] like Figure 1 , Figure 18 and Figure 19 As shown, the left atrial system 115 and the left atrial fluid buffer chamber 116 are interconnected, and the left atrial system 115 is also connected to the second oblique opening 11132 at the top of the oblique beam cover 1113. The left atrial system 115 includes a left atrial chamber 1151 and a left atrial chamber three-way valve 1152. The left atrial fluid buffer chamber 116 includes a fluid buffer cavity 1161 and a left atrial fluid buffer chamber inlet 1162. The left atrial fluid buffer chamber interface 1163 is a non-essential component; it can be a compliant chamber interface or a three-way valve interface.

[0116] In one embodiment of the invention, the liquid buffer cavity 1161 is L-shaped and connected to the side of the left atrial ventricle 1151. Alternatively, the liquid buffer cavity 1161 can also be designed as a straight cylinder, directly vertically connected to the top of the left atrial ventricle 1151.

[0117] The inner diameter of the left atrial chamber 1151 should be the same as the inner diameter of the second oblique opening 11132, and a sealing treatment is required during connection to ensure no leakage. This can be achieved by using sealing rings, sealant, or other suitable sealing methods.

[0118] Optionally, the left atrial system 115 and the left atrial fluid buffer chamber 116 can adopt the same design principles and manufacturing processes as the left ventricular system 111 to ensure the compatibility and consistency of the entire system. The left atrial system 115 includes a left atrial chamber 1151 and a left atrial chamber three-way valve 1152. The left atrial chamber 1151 is designed to simulate the function of the human left atrium, receiving blood returning from the circuit system 15 and facilitating flexible connection with other components via the three-way valve 1152, enabling pressure monitoring or venting operations. The left atrial fluid buffer chamber 116 includes a fluid buffer cavity 1161 and a left atrial fluid buffer cavity inlet 1162. The shape of the fluid buffer cavity 1161 can be designed as an "L" shape or a straight cylinder according to actual needs. The fluid buffer cavity 1161 is mainly used to temporarily store the fluid flowing in from the left atrial chamber 1151, while the left atrial fluid buffer cavity guide port 1162 is responsible for transporting excess fluid back to the left atrial fluid buffer cavity 116 or other designated locations through the loop system 15.

[0119] In addition, the left atrial fluid buffer chamber interface 1163 can be installed or not depending on specific testing needs. If it is necessary to simulate the effect of coronary perfusion on sinus pressure under physiological conditions, it can be set as a compliant chamber interface; if multi-channel fluid management is required, a three-way valve interface can be selected.

[0120] Through the above design, the left atrial system 115 and the left atrial fluid buffer chamber 116 can effectively simulate the physiological functions of the human left atrium and its related blood vessels, working together with other components to complete the closed-loop test process. This modular design not only improves the system's flexibility and adaptability but also facilitates maintenance and expansion.

[0121] like Figure 20 As shown, the drive system 12 should include at least three components: piston 121, drive chamber 122, and drive chamber exhaust valve 123.

[0122] Piston 121 is a reciprocating component that simulates the heart's pumping function by periodically squeezing the fluid in drive chamber 122. Drive chamber 122 is directly connected to outer chamber 1112, and the two together form a sealed chamber that is filled with fluid during machine operation. When piston 121 reciprocates, it repeatedly squeezes the fluid in drive chamber 122, thereby applying pressure to inner chamber 1111 to pump out the fluid from inner chamber 1111, simulating the contraction and relaxation of the left ventricle.

[0123] The drive chamber vent valve 123 is connected to the drive chamber 122 and is used to vent air and balance the pressure in the drive chamber, ensuring that the fluid dynamics characteristics of the system are not affected by the presence of air bubbles during operation.

[0124] The driving system 12 embodiment described in the present application only demonstrates the simplest driving schematic structure. In actual application, as an optional item, components or technologies such as liquid-permeable viscoelastic damping tube, etc. can be added in the driving cavity 122 to achieve more stable liquid driving effect. For example, the viscoelastic damping tube can help absorb the vibration generated during the driving process, improving the stability and accuracy of the system.

[0125] The specific structure and form of the driving cavity 122 should be designed according to actual conditions or aesthetic requirements to meet the needs of different application scenarios.

[0126] To ensure the normal operation of the system, the piston 121 must achieve high-precision structure and size adaptation and installation with the wall surface of the driving cavity 122. This not only ensures good sealing effect, but also ensures that the piston 121 will not be interfered during reciprocating motion. Specifically, the piston 121 should have high-precision manufacturing process to ensure that the gap between it and the wall surface of the driving cavity 122 is minimized to prevent leakage while avoiding excessive friction. The inner surface of the driving cavity 122 should be smooth and uniform to reduce the resistance of the piston 121 during movement and ensure consistent sealing performance throughout the working stroke.

[0127] Through the above design, the driving system 12 can effectively simulate the pumping function of the heart, and cooperate with other components to complete the closed-loop test process. This modular design not only improves the flexibility and adaptability of the system, but also facilitates maintenance and expansion. In addition, by introducing advanced damping technology and precision manufacturing process, the stability and reliability of the system can be further improved.

[0128] The power system 13 is equipped with a high-precision motor inside for driving the piston 121 to reciprocate. The motor is the power source of the entire driving system 12, ensuring accurate control of the liquid during the simulation of the heart's pumping process. Preferably, the high-precision motor in the power system 13 should have excellent linear output function. This means that the motor can provide stable and linear displacement output under different load conditions, ensuring that the reciprocating motion of the piston 121 can accurately simulate the contraction and relaxation process of the heart. Specifically, the high-precision motor needs to have high response speed and position control accuracy to ensure that the displacement, speed and acceleration of the piston 121 in each cycle can accurately match the preset heart motion curve. This not only helps to achieve precise control of fluid flow, but also improves the reliability and repeatability of test results. The motor has linear output function, and the linear output characteristic of the motor is crucial because it directly affects the motion trajectory of the piston 121. Excellent linear output means that the motor can maintain consistent performance under different loads, avoiding displacement deviation or speed fluctuation due to load changes. This stability is particularly important for simulating complex physiological conditions, such as simulating human blood circulation under different heart rates or pressure conditions.

[0129] The chamber assist system 14 consists of two enclosed hollow chambers, each with an interface communicating with an internal chamber and connected to other components via a hollow flexible tube. These two chambers are the aortic sinus compliance chamber 141 and the ascending aortic compliance chamber 142.

[0130] exist Figure 21 In the embodiment shown, both the aortic sinus compliance cavity 141 and the ascending aortic compliance cavity 142 are hollow cylindrical in shape, but their shape is not limited to this and can be designed into any suitable geometric shape according to actual needs.

[0131] The typical dimensions of the aortic sinus compliance lumen 141 and the ascending aortic compliance lumen 142 are approximately 10 mm in diameter and 30 mm in height. These dimensions can be the same or different, depending on the physiological compliance requirements being simulated. For example, the aortic sinus compliance lumen 141 can be connected via a flexible tube to the aortic sinus compliance lumen connection port 1131 on the personalized aortic valve and ascending aortic vascular system 113 to simulate the buffering effect of the coronary arteries on the aortic sinus region; the ascending aortic compliance lumen 142 can be connected to the corresponding location on the ascending aorta to simulate the elastic expansion and contraction behavior of the vessel wall, thereby more realistically reproducing the in vivo hemodynamic environment.

[0132] By setting up the above-mentioned compliance cavity structure, the chamber assist system 14 can effectively introduce the dynamic compliance characteristics of the vascular system, significantly improving the physiological realism of the in vitro test model.

[0133] The loop system 15 is used to deliver fluid from the ascending aortic fluid buffer chamber 114 to the left atrial fluid buffer chamber 116, thereby forming a complete closed-loop flow path. The loop system 15 mainly consists of a fluid heater 151, a peripheral damping regulator 152, and several connecting hoses.

[0134] The liquid heater 151 is a device capable of heating a test liquid flowing through it and setting a target heating temperature (typically 37°C) to simulate the normal human body temperature environment and ensure that the fluid properties (such as viscosity) are consistent with physiological conditions.

[0135] The peripheral damping regulator 152 is used to adjust the flow resistance of the fluid in the entire loop system 15. By setting different damping values, the flow characteristics of the fluid can be changed, thereby simulating the resistance effect generated by the human peripheral vascular system. This regulator can be implemented using a variable orifice valve, capillary array, or other equivalent structure to flexibly match the hemodynamic characteristics of different patients.

[0136] Connecting hoses are used to connect the above components with the ascending aorta liquid buffer chamber 114, the left atrium liquid buffer chamber 116 and other related interfaces. The connection of the hoses has been described in detail in the description of the above components (such as the ascending aorta liquid buffer chamber 114, the left atrium system 115, etc.), and will not be repeated here. However, it should be emphasized that all interfaces should be sealed reliably (such as using sealing rings, clamps or medical glue, etc.) when assembled to prevent leakage during operation and ensure the stability of system pressure and flow.

[0137] Through the above configuration, the loop system 15 not only realizes the circulation of the test liquid, but also has the functions of temperature control and peripheral resistance simulation, which significantly improves the physiological authenticity of the in-vitro test environment.

[0138] The control system 16 internally integrates devices for controlling the power system 13, computers connected to other external devices, signal conversion devices and image processing devices, etc. For different test requirements and evaluation functions, the internal components should be adjusted accordingly.

[0139] By connecting the three-way valves on the above components and the interfaces on the control system operation panel 161, the display devices on the operation panel can display the corresponding pressure values and other parameters in real time. The control system platform 162 can also be used to temporarily place an external notebook computer to improve the comfort and flexibility of human-computer interaction.

[0140] The control system 16 is used to centrally and standardized process data from multiple sensors, including but not limited to flow meters (electromagnetic, ultrasonic, etc.), pressure sensors, PIV / LDV / PTV velocity field measurements, structural displacement / strain measurements, and other external data sources. The system can perform preprocessing steps such as synchronization and phase alignment, sensor calibration and physical quantity conversion, filtering and denoising, wall positioning and near-wall interpolation / fitting, velocity gradient and strain rate tensor calculation, etc. on the original time series or phase data. The system automatically generates a series of time-domain and frequency-domain mechanical indicators, such as instantaneous flow, average flow, instantaneous / periodic pressure distribution, TAWSS, OSI, RRT, WSSG, local maximum shear, vortex strength, TKE, energy dissipation rate, pulse wave velocity PWV, input impedance spectrum, etc., and provides uncertainty evaluation and statistical confidence interval.

[0141] The control system 16 supports both real-time and offline operation modes:

[0142] Real-time mode: During the experiment, the key quantities are fed back to the controller through the streaming interface, which is used for closed-loop pump control or alarm.

[0143] Offline mode: Batch processing of phase-resolved data for subsequent analysis and visualization.

[0144] The output adopts standardized data structure and multiple export formats (CSV / NetCDF / HDF5 / VTK), and provides visualization instruments and machine interfaces (API / SDK) for connecting with numerical simulation, database or machine learning pipeline.

[0145] The module adopts modular plug-in architecture, allowing the insertion of new sensor drivers, near-wall derivative algorithms or custom derivative quantity calculators, and mandatory recording of measurement metadata (sampling rate, calibration coefficients, tracer particle information, fluid properties, etc.) to ensure the repeatability, traceability of results, and scalability and compliance in productization scenarios.

[0146] To improve the physiological relevance of in-vitro pulsatile flow reproduction, the module adds a pressure feedback regulation subsystem. This subsystem reserves and connects three-way valve interfaces at several key measurement locations of the personalized aortic model (such as near the valve orifice, the middle segment of the ascending aorta, or the aortic sinus) to communicate the measured site with high-speed pressure sensors without disrupting the closed loop. The sensors used can be piezoelectric, strain gauge or miniature pressure transmitters, which are amplified with low noise and anti-aliasing filtering before being synchronously acquired with the particle image velocimetry system 17 and outputting real-time pressure signals to the control unit.

[0147] The pressure signal is sent to the closed-loop controller of the pump controller, which can act as a pure pressure controller (i.e. automatically adjusting pump displacement / rotation speed / valve position according to the set target pressure-time curve) or a hybrid controller (simultaneously considering both flow and pressure targets in parallel or cascade). Common control strategies (real-time control based on PID) are supported, and more advanced control algorithms (feedforward compensation, model predictive control MPC) are reserved as optional items to improve transient tracking performance.

[0148] The operator can directly import the clinically measured pressure-time curve or manually edit / generate a custom pressure waveform file (multiple formats supported) through the human-machine interface of the computer. The controller will perform low-pass filtering and safety checking (detecting over-limit, sudden change, etc.) of the target curve before starting the experiment, and perform closed-loop regulation at a preset sampling frequency (recommended range for experiments: hundreds of hertz to thousands of hertz to ensure time resolution) during operation, and real-time pump driving instructions (displacement / speed / valve position) are issued to the pump driving unit. To ensure stability and safety, the controller includes anti-windup, sampling delay compensation, filtering / denoising and anti-oscillation strategies, and sets upper / lower limit safety thresholds and emergency stop logic: when the measured pressure exceeds the safety threshold or the sensor fails / loses signal, the system automatically enters safety mode (stops the pump or switches to a predefined safety curve), and an alarm prompt is displayed on the interface.

[0149] The hardware interface of the pressure feedback regulation is designed modularly: three-way valve, pressure sensor, signal conditioner and pump controller are connected with standardized electrical / fluidic interface, facilitating quick assembly between different individualized models. The controller records real-time pressure-flow time series, control commands and event logs and packages these data as metadata to be delivered to the computer for subsequent mechanical evaluation and uncertainty analysis. The subsystem also supports empirical calibration steps (e.g. obtaining sensor and pump response mapping through known impedance networks or known input-output curves) to improve the accuracy of closed-loop tracking.

[0150] Through the above design, the pressure feedback regulation is embodied in the form of closed-loop control in the operation of the pump: the system collects the pressure signal of the measured site in real time, compares the measured pressure with the preset target curve, and the closed-loop controller dynamically adjusts the instantaneous motion amount (displacement / speed, etc.) of the pump according to this, so as to make the pressure of the measured point approach the target value. The system simultaneously generates and outputs the corresponding time-displacement curve according to the real-time feedback and control command as the execution trajectory delivered to the pump driving unit and records it in the experiment log for reproduction and error analysis. For example, Figure 22 An embodiment of the time-displacement-velocity curve of the pump set according to the actual pressure feedback is given.

[0151] The device is used for performing in-vitro blood flow dynamics test after implanting the artificial aortic valve prosthesis in the aortic valve and ascending aortic vascular system, to evaluate the opening / closing performance, trans-valve pressure difference, paravalvular leakage, wall shear stress distribution and long-term fatigue risk of the prosthesis in the specific patient's anatomical environment.

[0152] Please refer to Figure 23 The aortic valve and ascending aorta in-vitro evaluation method is applied to a test system based on a patient-individualized customized aortic valve and ascending aorta physical model, and includes:

[0153] In step S100, the liquid pressure is controlled based on a preset pressure time sequence curve, so that the liquid flows from the left atrium buffer cavity into the left atrium model, and then flows into the left ventricle model through the one-way valve.

[0154] In step S200, the squeeze cavity is driven to act periodically based on a preset frequency, so that the left ventricle model ejects liquid, and then the liquid flows into the physical model of the aortic valve and ascending aorta through the flowmeter, and then flows into the ascending aorta liquid buffer cavity; wherein the liquid flows back from the ascending aorta liquid buffer cavity to the left atrium buffer cavity to form a closed loop.

[0155] In step S300, during the simulation test on the patient's aortic valve and ascending aorta physical model, the flowmeter, pressure sensor and high-frequency camera pre-arranged in the aortic valve and ascending aorta physical model are used to collect PIV velocity field, multi-point pressure time sequence and flow time sequence, and the corresponding time-frequency mechanical indexes are calculated according to the same, including:

[0156] a. calculating the instantaneous wall shear stress from the acquired PIV velocity field, and the instantaneous wall shear stress where μ is the dynamic viscosity of the liquid, represents the wall tangential velocity gradient, which is obtained by interpolation / fitting of the PIV velocity field of the near-wall profile.

[0157] b. calculating the time-averaged value from the instantaneous wall shear stress, and the time-averaged value where T is a preset test period (cardiac cycle).

[0158] c. calculating the oscillatory shear index from the instantaneous wall shear stress, and the oscillatory shear index

[0159] d. calculating the flow disturbance intensity from the acquired PIV velocity field, comprising: calculating the pulsatility characteristic parameter of the blood flow according to the plurality of continuously acquired velocity parameters and the corresponding average velocity; converting the pulsatility characteristic parameter into a velocity size representation and performing normalization processing to obtain the flow disturbance intensity; wherein the flow disturbance intensity is represented as and V k is the acquired blood flow velocity, V mean is the corresponding average velocity of the blood flow.

[0160] Step S400, calculating the corresponding period consistency index according to the test period of the simulation test, comprising: calculating the relative deviation between the velocity field of each test period and the average velocity across the period, and performing normalization processing to obtain the total jitter index; wherein the velocity field of one period is formed by all the velocity parameters of the period; the total jitter index is averaged to obtain the period consistency index; wherein the period consistency index E cycle is represented as

[0161] and V (i) represents the velocity field of one test period.

[0162] Step S500, integrating all the time-frequency mechanical indexes and period consistency indexes, and evaluating the condition of the aortic valve and ascending aorta of the patient according to the same, so as to serve as the basis for preoperative decision and instrument evaluation.

[0163] Specifically, in actual application, the test device for the aortic valve and the ascending aorta entity model can refer to Figures 1 to 21As shown, by conducting functional and mechanical tests on personalized aortic valve and ascending aorta solid models in vitro, the physiological and anatomical characteristics of patients can be accurately simulated, facilitating in vitro analysis and evaluation of the aortic valve and ascending aorta vessels. Simultaneously, simulation tests on the aortic valve and ascending aorta solid models can output device performance evaluation results that better reflect the patient's actual condition, thereby assisting in preoperative surgical planning, postoperative outcome prediction, device optimization design, and personalized medical customization.

[0164] The testing device comprises a fluid supply and buffer chamber (left atrial buffer chamber), a one-way valve, a left ventricular model and a variable pressure squeezing chamber (or a servo-driven reciprocating chamber), optional compliance or impedance units, a flow meter (electromagnetic / ultrasound optional), an ascending aortic fluid buffer chamber, and connecting tubing and interfaces. The aortic valve and ascending aortic models are installed in the testing device in a replaceable manner, allowing for customized aortic valve and ascending aortic models based on the patient's CT or MRI images, thus enabling in vitro simulation testing.

[0165] During the test, fluid needs to be driven from the left atrial buffer chamber into the left atrial model, and then through a one-way valve into the left ventricular model. At the same time, the pump periodically drives the squeezing chamber to produce blood ejection from the left ventricular model. The ejected fluid flows through a flow meter into the aortic valve and ascending aorta solid model, and then into the ascending aorta fluid buffer chamber, and finally flows back to the left atrial buffer chamber, forming a closed loop.

[0166] Therefore, pressure sensors, flow meters, and high-frequency cameras can be installed at the inlet / outlet and several key locations to collect relevant mechanical parameters. Simultaneously, programmable drivers (servo / stepping / reciprocating pumps or extrusion mechanisms) can be used to drive the extrusion chamber with adjustable amplitude and frequency to simulate heart rate and ejection curves. Pressure / flow data from pressure sensors / flow meters can also be accepted for closed-loop control to accurately reproduce the target pressure-flow waveform.

[0167] Furthermore, to improve the physiological relevance of the in vitro pulsating flow reproduction, three-way valve interfaces can be reserved and connected at several key measurement locations (such as near the valve orifice, the middle segment of the ascending aorta, or the aortic sinus) of the aortic valve and ascending aorta solid model, so as to connect the measured part to the high-speed pressure sensor without disrupting the closed loop.

[0168] In practical applications, operators can directly import clinically measured pressure-time curves or manually edit and generate pressure waveforms, i.e., pressure-time curves, through the human-computer interaction interface. During operation, the pump controller will perform closed-loop regulation at a preset sampling frequency and send the pump drive commands (displacement / speed / valve position) to the pump drive unit in real time to drive the liquid to complete a closed loop, simulating the physiological condition of the patient's aortic valve and ascending aorta.

[0169] Finally, the corresponding time-frequency mechanical indicators and cycle consistency indicators are calculated according to the mechanical parameters collected during the test, to generate a standardized report (including original time sequence, phase average field, near-wall profile graph, wall stress risk heat map) as the basis for preoperative decision-making and instrument evaluation.

[0170] It needs to be added here that the flow disturbance intensity in the time-frequency mechanical indicators is a dimensionless "chaotic or not index" obtained by comparing the "velocity jitter amplitude" (root mean square) with the "average velocity", and the larger this index is, the more unstable the flow is. It can be used to quantify the unstable disturbance of the subvalvular high shear area, regurgitant area, etc., as a risk prompt or threshold value for test condition screening.

[0171] Therefore, by taking the difference between V k and V mean , the mean value is removed, and only the pulsatile characteristics of the blood flow are retained. By squaring and square rooting, the positive and negative pulsatile characteristics are not offset, and the index is expressed in terms of velocity. Finally, through normalization processing, the flow disturbance intensity under different test conditions can be used for lateral comparison. Among them, V mean can be written as or also as the root mean square of the three-component combined velocity, or as a monotonic transformation of the standard deviation and other second moments, etc., and no limitation is made in this regard.

[0172] In addition, the cycle consistency indicator is to regard the "whole waveform / whole velocity sampling" of each test cycle as a velocity field V (i) , and to take the difference between V mean across cycles, to see how big the difference between the two is. Correspondingly, the size of the difference is quantified into a scalar that does not look at positive and negative but only at strong and weak using the ||·|| operation, and then it is divided by ||·|| to make it dimensionless, to avoid the dimensional / scale effect that the larger the mean value is, the larger the difference naturally is. Finally, the total incidental jitter is converted into the overall consistency level by averaging all test cycles, which can represent the inconsistency degree of this group of tests at different cycle levels, and the smaller the value is, the more consistent it is.

[0173] Therefore, without changing the essential connotation of "comparing the relative deviation of each cycle and the mean value across cycles", it falls within the scope of protection of the present application, for example, the final averaging method can be arithmetic mean, weighted mean (according to heart rate stable segment, heart phase weight, etc.) and other methods; or use the complementary parameter of the cycle consistency indicator, such as C cycle = 1-E cycle ; or use other parameters for calculation, such as pressure, flow, etc.

[0174] At the same time, the cycle consistency indicator E cvcleThe norm in the middle is replaced by the L2 norm, which is the square-integral-root compression:

[0175]

[0176] The modifications and improvements made by those skilled in the art to the embodiments of the present application without departing from the spirit of the present application also fall within the scope of the patent application for invention.

[0177] In a specific embodiment, the solid model of the aortic valve and ascending aorta of the patient can be personalized by the following method:

[0178] Taking the CT image of the heart part of the patient as an example, first, the complete CT image is segmented by the gray threshold value, and the voxel region of interest containing only the aortic valve and the ascending aorta is extracted, i.e., the corresponding image region. Then, the noise after threshold segmentation is eliminated and the cavity is filled by morphological processing, so that the extracted image region is more complete.

[0179] Secondly, on this basis, the sub-blocks containing only the aortic valve part and the ascending aorta part are cut out, so as to reduce the redundant information and reduce the data dimension, so as to improve the calculation efficiency of the subsequent convolutional neural network. At the same time, a number of sub-blocks are standardized and size-unified processed and integrated.

[0180] Further, the image data processed above is input into the convolutional neural network (first convolutional neural network) to realize multi-class segmentation, i.e., to segment the valve, vessel trunk and vessel branch in the aortic valve / ascending aorta. At this time, if the ascending aorta has an aneurysm or a dissection, based on the ascending aorta mask output by the first convolutional neural network, the curved ascending aorta in the image is straightened by using the skeletonization and centerline optimization algorithm, the relative positions of the true vessel lumen, aneurysm or false vessel lumen in the ascending aorta are simplified, and the processed image is input into the second convolutional neural network to accurately distinguish the true vessel lumen, aneurysm or false vessel lumen in the ascending aorta.

[0181] Finally, the segmentation results of the first convolutional neural network and the second convolutional neural network are mapped back to the original space by inverse transformation, and morphological repair is performed to obtain the vascular image of the aortic valve part and the ascending aorta part.

[0182] Based on the above, the image of the aortic valve and ascending aorta of the patient can be preprocessed by reverse three-dimensional modeling, for example, collecting DICOM / layer images and performing registration, denoising and pixel-level intensity standardization, and converting the processed image data into voxels or surface grids to generate a "intuitive three-dimensional model" based on the original image (initial model of the aortic valve / ascending aorta). Then, the initial model is smoothed, hole repaired, topologically corrected, and thin / thick wall consistency checked to identify and repair broken edges and unreasonable geometry, and finally, a personalized aortic valve and ascending aorta physical model is printed by 3D printing to support stereolithography / powder bed fusion, silicone / resin reverse molding, CNC machining and any combination. At the same time, transparent or translucent shell materials can be selected according to experimental requirements to ensure optical imaging conditions.

[0183] It can be understood that, as shown in Figure 13 , by customizing the physical model of the aortic valve and ascending aorta of the patient, the inner surface morphology (valve opening area, calcification morphology, sinus structure, bending radius, etc.) can be ensured to be one-to-one mapped with the patient image, and if necessary, replaceable valve leaflets or calcification pieces can be embedded in the inner cavity for repeated testing.

[0184] It should be further pointed out that by data segmentation of the patient's CT image and reverse modeling to generate a manufacturable STL / CAD model, and then 3D printing / reverse molding to customize the physical model. Accordingly, the geometry of the physical model can be measured optically or scanned by CT after printing to calibrate the error value between the model and the actual physiological structure.

[0185] In this regard, the CT image of the aortic valve and ascending aorta physical model can be obtained and compared with the image of the aortic valve and ascending aorta obtained by processing the CT image of the patient's heart to check whether the aortic valve and ascending aorta physical model meets the standard.

[0186] Specifically, the scale index of the error value, i.e. the geometric reproduction degree (comparison result), is defined as: R reproducibility = volume overlap / reference volume, which can be further expressed as to complete the image comparison.

[0187] wherein, Ω model represents the CT image of the aortic valve / ascending aorta physical model, and Ω refThe image of the aortic valve site / ascending aorta site obtained by CT image processing of the patient's heart site.

[0188] It can be understood that the geometric reproducibility provided above is used to calibrate the overlap between the medical image and the printed physical model as a "morphological reliability" constraint in the "morphology-mechanics" closed loop, but is not limited to this comparison method. For example, the difference between the two can also be measured by Hausdorff distance and its monotonic transformation, and the two can also be represented by CT / segmented voxels, meshes or point clouds and other data formats, which are not limited.

[0189] Based on the above, the actual process of the aortic valve and ascending aorta extracorporeal evaluation method provided in the embodiment can be seen from Figure 24 The schematic includes:

[0190] Step 1, image acquisition and intelligent segmentation

[0191] Acquire patient CT / MRI (at least one frame of systolic and diastolic period for displaying maximum valve leaflet opening morphology), and segment the aortic root, aortic sinus, valve leaflet and ascending aorta volume / surface profile through image processing. Output reference geometric data (3D surface or voxel data) to ensure that the manufactured physical model is consistent with the true geometry of the patient.

[0192] Step 2, individualized physical model rapid manufacturing and calibration

[0193] According to the segmentation data of the above steps, a manufacturable STL / CAD model is generated by reverse modeling, and a physical model is made by 3D printing / inverse molding. The inlet area and morphology of the chamber are determined by the maximum valve leaflet opening morphology. After printing, the geometry of the physical model is obtained by optical measurement or CT secondary scanning to calibrate the error value between the model and the actual physiological structure.

[0194] Step 3, implanting artificial prosthetic valve

[0195] Before installing the individualized physical model, the artificial prosthetic valve is loaded and released in the personalized ascending aorta chamber through a special intervention. The release morphology of the artificial prosthetic valve will be consistent with the real situation.

[0196] Step 4, module assembly and sensor arrangement

[0197] The physical model is installed in the chamber of the test device, and pressure sensors are installed at key positions (below the valve, near the valve, in the middle of the ascending aorta, and in the sinus region). Flow meters are installed at the inlet / outlet, optical windows are reserved for PIV, and high-frequency cameras are arranged.

[0198] Step5, Test initialization (two water filling and gas evacuation)

[0199] Driving waterway (denoted as A way): pump + driving medium → extrusion of outer cavity 1112 to drive the deformation of "inner cavity 1111" (note: A way is not communicated with the fluid path to be tested).

[0200] Test waterway (denoted as B way): inner cavity → flow through personalized model → ascending aortic buffer → backflow to left atrium (forming a closed loop) - all data of in vitro test come from B way (velocity field, pressure, WSS, etc.).

[0201] Step6, Set target and start pump (use pressure target or flow target)

[0202] The operation interface imports the preset pressure time curve, and is driven by pressure feedback to better reproduce the clinical pressure field.

[0203] Step7, Start the device to start the initial cycle

[0204] The pump starts to work according to the initial rhythm, first stabilizes the cycle in open loop mode, and detects whether there are bubbles, sealing loss or abnormal resistance in B way.

[0205] Step8, Start pressure feedback control

[0206] The target of closed loop pressure feedback control is to make the instantaneous pressure p meas(t) of the measured point follow the preset target pressure curve p target(t) . The system collects pressure signals in real time at the pre-marked measuring point (such as near the valve or in the middle of the ascending aorta), and calculates the pressure error:

[0207] e(t) = p target(t) -p meas(t) ,

[0208] The error e(t) is sent to the controller, and the controller generates control output u(t) according to the established control law, which is usually in the form of PID:

[0209]

[0210] The control output u(t) is converted into the driving instruction of the pump. If the pump is a reciprocating structure, u(t) is usually regarded as the displacement rate, that is:

[0211] (if u is output in the form of displacement rate),

[0212] The instantaneous flow rate is approximately:

[0213] Q(t) = A p × u(t),

[0214] where Ap effective area of the piston;

[0215] The control cycle works continuously, and adjusts the displacement / speed of the pump in real time to make p meas(t) approximate p target(t) At the same time, the actual time-displacement curve x(t) (or displacement rate u(t)) issued is recorded as an experimental log for reproduction and error analysis.

[0216] Step 9, Synchronous acquisition: PIV and multi-point measurement

[0217] According to the set phase trigger scheme (phase-locked or time-resolved), PIV camera, pressure sampling and flow meter recording are triggered synchronously to obtain mechanical parameters including but not limited to v(x, t) (velocity field), p(x_i, t) (multi-point pressure time series), Q(t) (flow time series).

[0218] Step 10, Abnormal handling and safety strategy

[0219] If the sensor fails or p meas(t) is out of the safety range, the controller should trigger an emergency stop and record the fault log; it is recommended to implement control robustness measures such as anti-windup, anti-oscillation filtering and time delay compensation.

[0220] Step 11, Generate standardized report

[0221] Generate a standardized report containing original time series, phase-averaged field, near-wall profile, and wall stress risk heat map, which can be used as a basis for preoperative decision-making and device evaluation.

[0222] In another specific embodiment, considering the case where the patient's aortic valve and ascending aorta are implanted with an artificial prosthetic valve, the artificial prosthetic valve can also be loaded and released in the chamber of the ascending aorta solid model after the solid model is made through a special intervention, and the release form of the artificial prosthetic valve will be consistent with the real situation. Finally, compare the time-domain and frequency-domain mechanical indicators and cycle consistency indicators of the implanted artificial prosthetic valve and the unimplanted artificial prosthetic valve, analyze the difference and perform statistical test to generate a standardized report.

[0223] It should be noted that the step division of the above methods is only for the purpose of clear description, and when implemented, it can be combined into one step or some steps can be split and decomposed into multiple steps, as long as the same logical relationship is included, and it is within the protection scope of the patent; adding irrelevant modifications or introducing irrelevant designs in the algorithm or process, but not changing the core design of the algorithm and process, are within the protection scope of the patent.

[0224] The aortic valve and ascending aorta in vitro testing device of the application realizes in vitro testing of the aortic valve and the ascending aorta based on the personalized physiological anatomical characteristics of different patients. It can not only quickly output diversified functional parameters, but also perform individual in vitro testing on the artificial aortic valve to output equipment performance evaluation results that are more in line with the actual situation of the patient. These characteristics greatly improve the accuracy and reliability of preoperative surgical planning, postoperative outcome prediction, instrument optimization design and personalized medical customization.

[0225] Through the above technical effects, the application not only solves many deficiencies in the prior art, but also provides strong technical support for the diagnosis, treatment planning and research and development of medical instruments of cardiovascular diseases. The modular design and flexible expansion also provide a broad space for future research and application.

[0226] The above embodiments only exemplarily illustrate the principles and effects of the application, and are not used to limit the application. Any person skilled in the art can modify or change the above embodiments without departing from the spirit and scope of the application. Therefore, all equivalent modifications or changes completed by those skilled in the art without departing from the spirit and technical thought disclosed by the application should be covered by the claims of the application.

Claims

1. An aortic valve and ascending aorta in-vitro test evaluation apparatus, characterized by, Comprise: a chamber system, a driving system, a chamber auxiliary system, a loop system, a control system and a particle image velocimetry system; The chamber system is used for simulating a blood flow path, comprising: a left ventricle system for simulating left ventricle contraction to drive fluid; aortic valve and ascending aorta vascular system, the internal cavity structure of which is manufactured according to specific medical image data by reverse modeling, and is consistent with the actual aortic valve maximum opening shape, aortic sinus geometry and ascending aorta direction; an ascending aorta liquid buffer cavity connected with the chamber outlet end of the aortic valve and ascending aorta vascular system, used for temporarily storing the liquid flowing out from the aortic valve and ascending aorta vascular system; a left atrium system and a corresponding liquid buffer cavity, the left atrium system being in communication with the left ventricle system and being used for receiving backflow liquid and forming a closed circulation; The driving system is connected with the left ventricle system and is used for providing a periodic pulsation driving force to simulate heart beating; The loop system connects the outlet of the aortic valve and ascending aorta vascular system with the left atrium liquid buffer cavity, constitutes a closed circulation loop of test fluid, and contains components for adjusting fluid temperature and peripheral resistance; The control system is used for setting a target pressure or flow curve, and implementing closed-loop feedback control on the driving system based on the real-time collected pressure signal, so that the test point pressure dynamically tracks the preset target; The particle image velocimetry system is arranged in the optical visible area of the personalized aortic valve and ascending aorta vascular system, and is used for non-invasively acquiring blood flow dynamics parameters such as fluid velocity field, wall shear stress and relative particle residence time. The left ventricle system comprises:

2. The aortic valve and ascending aorta testing device of claim 1, wherein, an outer chamber, the bottom of which is provided with an outer chamber sealing valve and an inner chamber sealing valve, the outer chamber sealing valve being connected with the outer chamber, and the bottom of the outer chamber being further provided with an opening, the opening being connected with the driving system; an inner chamber, which is arranged inside the outer chamber and has its bottom connected to the inner chamber sealing valve through a hose; a sloping beam cover, which is arranged on the top of the outer chamber and the inner chamber and is sealingly connected therewith, and is connected with the aortic valve and ascending aorta vascular system, the left atrium system and the left ventricle system. The sloping beam cover has two slopes, a first sloping opening and a second sloping opening being arranged in communication with the aortic valve and ascending aorta vascular system and the left atrium system respectively, and the first sloping opening and the second sloping opening being in communication with the inner chamber.

3. The aortic valve and ascending aorta testing device of claim 2, wherein, A detachable one-way valve is arranged at the first sloping opening and / or the second sloping opening, and the one-way valve is configured to allow fluid to flow only from the left ventricle to the ascending aorta or from the left atrium to the left ventricle.

4. The aortic valve and ascending aorta testing device of claim 3, wherein, A flow meter is further arranged detachably between the slope with the first sloping opening and the aortic valve and ascending aorta vascular system.

5. The aortic valve and ascending aorta testing device of claim 3, wherein, The aortic valve and ascending aorta vascular system comprises:

6. The aortic valve and ascending aorta testing device of claim 1, wherein, a chamber; an aortic sinus compliance cavity connection port, one end of which is in communication with the aortic sinus part of the chamber, and the other end is connected to the chamber auxiliary system; ​ a liquid outlet, one end of which is in communication with the top of the chamber, and the other end is connected to the circuit system; a sub-valve three-way valve interface and a supra-valve three-way valve interface, which are respectively in communication with the inlet and outlet of the chamber.

7. The aortic valve and ascending aorta testing device of claim 6, wherein, The aortic valve and ascending aorta vascular system is a hard structure integrally formed by 3D printing.

8. The aortic valve and ascending aorta testing device of claim 6, wherein, The aortic valve and ascending aorta vascular system comprises a transparent shell and a chamber arranged in the shell, a hollow structure is formed between the chamber wall of the chamber and the transparent shell, and the chamber wall is a flexible structure.

9. The aortic valve and ascending aorta testing device of claim 1, wherein, The personalized aortic valve and ascending aorta vascular system is prepared by the following steps: Obtaining CT, MRI or ultrasound images of the patient at the end of the systolic period of the heart; Segmenting the three-dimensional profile of the aortic root, aortic sinus, valve leaflet and ascending aorta; After removing the significantly calcified area, reverse modeling is performed to generate an STL / CAD model; A physical model with a hollow cavity is manufactured by 3D printing, reverse molding or machining.

10. The aortic valve and ascending aorta testing device of claim 1, wherein, The control system integrates a pressure feedback regulation subsystem, a high-speed pressure sensor is arranged at the near-valve orifice, the middle of the ascending aorta or the aortic sinus, and a PID control algorithm is used to dynamically adjust the driving system based on the real-time pressure signal, so that the measured pressure waveform tracks the preset clinical target pressure curve.

Images