Intubation assembly and blood pump
By designing a flexible membrane non-elastic stent cannula assembly, the problem of existing cannulas being unable to change their cross-sectional area was solved, improving the blood pumping efficiency of the blood pump and reducing the difficulty of implantation, thus achieving stable fixation.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-08
- Publication Date
- 2026-03-31
AI Technical Summary
The cross-sectional area of existing cannulas cannot be changed according to changes in blood flow, resulting in low pumping efficiency of the blood pump.
Design a cannulation assembly whose main section is made of a flexible membrane without an elastic stent, capable of radial expansion or contraction within a small range when blood flow changes, in order to adapt to changes in blood flow and increase or decrease the flow area.
It improves the pumping efficiency of the blood pump, reduces the difficulty of blood pump implantation, and the cannula can be stably clamped and fixed by the pulmonary valve or aortic valve to prevent loosening and dislodgement.
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Figure CN121754794A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of medical device technology, and in particular to a cannulation assembly and a blood pump. Background Technology
[0002] An interventional catheter pump, also known as a blood pump, is typically inserted from a blood vessel into the ventricles of a patient's heart to assist the heart in pumping blood from the ventricles into the arteries, thus supporting the patient's blood circulation. A blood pump generally includes a cannula that forms a flow channel; this cannula is flexible enough to adapt to the curvature of the patient's tissues. However, the cross-sectional area of this cannula (i.e., the flow surface area) cannot change according to variations in blood flow, limiting the pumping capacity to the radial dimensions of the cannula, resulting in relatively low pumping efficiency. Summary of the Invention
[0003] Therefore, it is necessary to provide a cannulation assembly and blood pump whose flow surface area can be changed according to changes in blood flow to address the above problems.
[0004] In one embodiment of this application, the cannulation assembly includes a proximal tube, a distal tube, and a cannula; the proximal tube has a first opening; the distal tube has a second opening; the cannula has a fluid flow channel connecting the first opening and the second opening; the cannula has a first tube segment, a second tube segment connected together, and a main tube segment located between the first tube segment and the second tube segment; the first tube segment is fixedly connected to the proximal tube; the second tube segment is fixedly connected to the distal tube; the first tube segment, the main tube segment, and the third tube segment all have flexible membranes, at least the main tube segment does not have an elastic support, and the main tube segment is tubular in its natural state.
[0005] In one embodiment of the blood pump provided in this application, the blood pump includes an impeller and a cannulation assembly; the cannulation assembly refers to the above embodiment; the impeller is rotatably disposed in the proximal tube of the cannulation assembly.
[0006] The blood pump of this application uses a cannula whose first, second, and main sections all have flexible membranes, and the main section lacks an elastic support. This makes the main section less rigid than traditional cannulas, resulting in a more flexible cannula. Besides being able to bend to adapt to the shape of the patient's tissues, the main section can also undergo a small range of radial deformation. Therefore, when the frequency of the blood pump's control motor changes according to a certain pattern, causing changes in blood flow, the flow surface area of the main section can change accordingly, allowing blood to pass through the main section more smoothly. For example, when the blood flow increases, the main section expands slightly, increasing the flow surface area, allowing the increased blood flow to pass through the cannula smoothly. This increases the amount of blood delivered by the cannula and improves the pumping efficiency of the blood pump. When blood flow decreases, the main tube contracts slightly, restoring it to its natural or at least near-natural tubular shape, rather than shrinking into a deflated balloon shape. This allows the main tube to be stably held and fixed by the pulmonary or aortic valve, preventing it from loosening and falling off. Attached Figure Description
[0007] Figure 1 This is a schematic diagram of the structure of a blood pump provided in one embodiment of this application.
[0008] Figure 2 for Figure 1 The provided schematic diagram of the blood pump structure after cannulation.
[0009] Figure 3 for Figure 1 A schematic diagram of the blood pump provided.
[0010] Figure 4 for Figure 1 A cross-sectional view of the blood pump is provided.
[0011] Figure 5 for Figure 4 The provided image shows a magnified view of the blood pump at point A.
[0012] Figure 6 for Figure 1 The provided schematic diagram shows the proximal tube, motor, and impeller of the blood pump.
[0013] Figure 7 for Figure 1 The provided diagram shows the proximal tubing, motor, and impeller of the blood pump.
[0014] Figure 8 for Figure 1 A schematic diagram of the distal tubing and non-invasive flexible components of the provided blood pump.
[0015] Figure 9 for Figure 4 The provided image shows a magnified view of the blood pump at point B.
[0016] Figure 10 for Figure 1 The provided longitudinal cross-sectional view after the blood pump is inserted into the interventional guidewire.
[0017] Figure 11 for Figure 10 A cross-sectional view of the blood pump cannula provided.
[0018] Figure 12 for Figure 4 A schematic diagram of one embodiment of the provided cannula.
[0019] Figure 13 for Figure 4 A schematic diagram of another embodiment of the provided cannula.
[0020] Figure 14 for Figure 13 A schematic diagram showing the increased membrane wall thickness at both ends of the provided cannula.
[0021] Figure 15 for Figure 4 A schematic diagram of another embodiment of the provided cannula.
[0022] Figure 16 This is a schematic diagram of a traditional intubation device.
[0023] Figure 17 This is a schematic diagram of the structure of a blood pump provided in another embodiment of this application.
[0024] Figure 18 for Figure 17 A cross-sectional view of the blood pump is provided.
[0025] Figure 19 for Figure 17 The provided image shows a magnified view of the blood pump at point C.
[0026] Figure 20 for Figure 17 The provided image shows a magnified view of the blood pump at point D.
[0027] Figure 21 for Figure 18 A magnified view of the proximal end of the provided cannula.
[0028] Figure 22 for Figure 18 A magnified view of the distal end of the cannula provided.
[0029] Figure 23 This is a longitudinal cross-sectional view of a blood pump provided in another embodiment of this application.
[0030] Figure 24 for Figure 23 The provided cross-sectional view of the blood pump in the middle of the cannula.
[0031] Figure 25 This is a schematic diagram of the structure of a blood pump provided in another embodiment of this application.
[0032] Figure 26 for Figure 25 A magnified view of a portion of the blood pump at point E.
[0033] Figure 27 for Figure 25 The main view of the blood pump provided.
[0034] Figure 28 for Figure 27 The provided cross-sectional view of the blood pump along the JJ line.
[0035] Figure 29 for Figure 28 The provided image shows a magnified view of the blood pump at point F.
[0036] Figure 30 for Figure 28 The provided image shows a magnified view of the blood pump at point G.
[0037] Figure 31 for Figure 28 The provided image shows a magnified view of the blood pump at point H.
[0038] Figure 32 for Figure 27 The provided cross-sectional view of the blood pump along line KK.
[0039] Figure 33 for Figure 32 Enlarged cross-sectional view of the flexible sheath, support wire, and lead wire of the provided blood pump.
[0040] The labels in the attached diagram are explained as follows: 10. Blood pump; 11. Central axis; 12. Motor; 13. Catheter; 20. Interventional guidewire; 100. Proximal cannula; 101. First opening; 102. First adhesive reservoir; 103. Through hole; 110. Opening cannula; 120. Adaptor tube; 130. Mounting bracket; 130a. First insertion hole; 130b. Hole entrance; 130c. Support surface; 131. Base; 1311. First surface; 1312. Second surface; 132. Support arm; 132a, Radial channel; 200, Distal tube; 201, Second opening; 202, Second adhesive reservoir; 210, Mounting end; 210a, Second insertion hole; 210b, Guide wire hole; 211, Flow guide cone; 212, Connecting seat; 212a, Distal end face; 212b, Circumferential side face; 220, Tube body; 300, Inserted tube; 301, Fluid flow channel; 310, First tube section; 311, First end flexible membrane; 320, Second tube section; 322. Second end flexible membrane; 330, main pipe section; 331, main flexible membrane; 332, proximal end; 333, distal end; 334, main body; 400, impeller; 500, support wire; 510, first end; 520, second end; 610, first rectifier tube; 611, first fixed section; 612, first rectifier section; 620, second rectifier tube; 621, second fixed section; 622, second rectifier section; 602, spring metal layer; 601, flexible 900. Membrane layer; 910. Non-invasive flexible component; 920. Flexible long axis portion; 700. Ball head; 700. Flexible sheath; 710. First inner cavity; 720. Second inner cavity; 701. First arc surface; 702. Second arc surface; 703. Side plane; 704. Cylindrical surface; 800. Sensor; 810. Probe; 811. Sensing surface; 820. Wire; 821. First line segment; 822. Second line segment; 823. Third line segment; 824. Fourth line segment. Detailed Implementation
[0041] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.
[0042] In the description of this application, it should be understood that if the terms "center", "longitudinal", "transverse", "length", "width", "membrane wall thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.
[0043] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0044] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.
[0045] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.
[0046] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.
[0047] It should be noted that the terms "distal" and "proximal" in the text are only used to indicate relative positional relationships. The "distal" end of a component refers to the end that enters the patient's body first and / or is farther away from the operator during normal operation, while the "proximal" end refers to the end that enters the patient's body later and / or is closer to the operator.
[0048] Please see Figure 16 Traditional blood pump cannulation assemblies typically include a cannula for forming a fluid flow channel. This cannula 300' is usually a multi-layered structure, with at least one layer being an elastic stent 340 and a flexible membrane covering the elastic stent 340; wherein the elastic stent 340 extends from one end of the cannula 300' to the other end and surrounds the entire fluid flow channel 301 of the cannula 300'. The elastic stent 340 is made of a shape memory material and is typically fabricated as a helical stent, a mesh stent woven into a grid shape, or a coil stent composed of multiple coils spaced axially. This elastic stent 340 allows the cannula 300' to be flexible, thus enabling it to adapt to the curved shapes of tissues within the patient's body. However, this elastic stent 340 also increases the rigidity of the cannula 300', making it difficult for the cannula 300' to expand and contract radially. As a result, the cross-sectional area (i.e., the flow surface area) of the cannula 300' cannot change according to the blood flow rate, which limits the blood flow rate to the radial dimension of the cannula 300', resulting in low blood pumping efficiency.
[0049] Based on this, such as Figures 1 to 3As shown, one embodiment of this application provides a cannulation assembly that can be applied to a blood pump 10. The cannulation assembly includes a proximal cannula 100, a distal cannula 200, and a cannula 300. The proximal cannula 100 has a first opening 101; the distal cannula 200 has a second opening 201, one of which, the second opening 201 and the first opening 101, is a blood inlet, and the other is a blood outlet. The cannula 300 has a fluid flow channel 301 forming inside, connecting the first opening 101 and the second opening 201. The cannula 300 has a first tube segment 310, a second tube segment 320, and a main tube segment 330 located between the first tube segment 310 and the second tube segment 320. The first tube segment 310 is fixedly connected to the proximal cannula 100; the second tube segment 320 is fixedly connected to the distal cannula 200; the first tube segment 310, the second tube segment 320, and the main tube segment 330 all have flexible membranes, but the main tube segment 330 does not have an elastic support (see [link to relevant documentation]). Figure 12 Furthermore, the main section 330 is tubular in its natural state.
[0050] Specifically, the blood pump 10 can be a left ventricular interventional pump or a right ventricular interventional pump. When the blood pump 10 is a right ventricular interventional pump, the first opening 101 is the blood inlet and the second opening 201 is the blood outlet. During delivery, the blood pump 10 is pushed from the right ventricle to the pulmonary artery, so that the main tube segment 330 of the cannula 300 crosses the pulmonary valve, the first opening 101 is located in the right ventricle, and the second opening 201 is located in the pulmonary artery. When the blood pump 10 is a left ventricular interventional pump, the first opening 101 is the blood outlet and the second opening 201 is the blood inlet. During delivery, the blood pump 10 is pushed from the aorta to the left ventricle, so that the main tube segment 330 of the cannula 300 crosses the aortic valve, the second opening 201 is located in the left ventricle, and the first opening 101 is located in the aorta.
[0051] Because the main tube segment 330 of the cannula 300 has a flexible membrane but does not contain an elastic support, the rigidity of at least the main tube segment 330 of the cannula 300 is less than that of a conventional cannula 300'. The main tube segment 330 is more flexible, which means that, on the one hand, the main tube segment 330 does not need to be pre-shaped into a curved form, and it is easier to bend to adapt to the curvature of tissues within the patient's body; on the other hand, the main tube segment 330 can also undergo a smaller range of radial deformation. During blood flow through the fluid channel 301 of the cannula 300, if the blood flow increases, the main tube segment 330 can expand slightly radially outward to allow the increased blood flow to pass through the cannula 300, thereby increasing the amount of blood delivered by the cannula 300 and improving the pumping efficiency of the blood pump. Subsequently, if the blood flow decreases, the main tube segment 330 of the cannula 300 can contract radially inward to return to its initial state.
[0052] Taking the blood pump 10 as a right ventricular interventional pump as an example, when the blood pump 10 is working, the motor 12 of the blood pump 10 drives the impeller 400 to rotate. Blood enters the main tube section 330 of the cannula 300 from the proximal tube 100, flows from the main tube section 330 into the distal tube 200, and finally exits from the distal tube 200. The control system of the blood pump 10 controls the frequency of the motor 12 according to the rhythm of the heartbeat and the pumping of blood, so that the frequency of the motor 12 changes in a certain pattern (such as, but not limited to, changing according to a sine and cosine pattern). This causes the blood flow pumped by the blood pump 10 to fluctuate regularly (similar to the flow rate sometimes being large and sometimes small). The main tube section 330 of the cannula 300 can expand and contract slightly according to the changes in blood flow, so that blood can pass smoothly through the main tube section 330. For example, when the frequency of motor 12 increases, the blood flow rate also increases, and the blood pressure increases. Under the pressure of the blood, the main pipe section 330 of the cannula 300 expands adaptively, increasing the radial dimension of the main pipe section 330 and the area of the flow surface, so that a large amount of blood can pass through the main pipe section 330. Then, when the frequency of motor 12 decreases, the blood flow rate also decreases, and the main pipe section 330 of the cannula 300 returns to its initial state, and the cycle continues.
[0053] It should be noted that the flexible membrane of the cannula 300 is typically made of a material with greater hardness than that of medical balloons (silicone rubber), such as TPU (thermoplastic polyurethane elastomer). Therefore, even if the main tube segment 330 does not have an elastic support, it can maintain its tubular shape in its natural state. Of course, by appropriately designing the membrane wall thickness of the main tube segment 330 (e.g., but not limited to 0.5mm~0.12mm), it can be made to maintain its tubular shape well in its natural state. Furthermore, the diameter of the cannula 300 is usually small. Therefore, when the main tube segment 330 of the cannula 300 does not have an elastic support, the expansion and contraction of the main tube segment 330 along its radial direction is a small deformation, and the change in diameter is small, generally not easily observed with the naked eye; that is, it will not experience the large-scale expansion and contraction with a diameter increase as seen in catheter balloons. This ensures that when the main tube segment 330 of the cannula 300 expands and contracts back to its initial state, the main tube segment 330 remains tubular instead of shrinking into a deflated balloon shape. This allows the main tube segment 330 to be stably clamped and fixed by the pulmonary valve or aortic valve, preventing the main tube segment 330 from loosening and falling off the pulmonary valve or aortic valve.
[0054] Therefore, the cannula 300 used in the blood pump 10 of this application has a flexible membrane but no elastic support in its main pipe section 330. This makes the rigidity of the main pipe section 330 of the cannula 300 less than that of a conventional cannula 300', and the main pipe section 330 is more flexible. In addition to being able to bend to adapt to the curved shape of the patient's internal tissues, the main pipe section 330 can also undergo a small range of radial deformation. Thus, when the frequency of the control motor of the blood pump 10 changes in a certain pattern, causing changes in blood flow, the flow surface area of the main pipe section 330 of the cannula 300 can change according to the change in blood flow, so that blood can pass through the main pipe section 330 more smoothly. For example, when the blood flow increases, the main pipe section 330 expands slightly accordingly, increasing the flow surface area of the main pipe section 330, which allows the increased blood flow to pass through the cannula 300 smoothly, increasing the amount of blood delivered by the cannula 300 and improving the pumping efficiency of the blood pump. When blood flow decreases, the main tube segment 330 contracts slightly, returning to its natural or at least near-natural tubular shape, rather than shrinking into a deflated balloon shape. This allows the main tube segment 330 to be stably held and fixed by the pulmonary valve or aortic valve, preventing it from loosening and falling off.
[0055] Furthermore, since the cannula 300 can adapt to radial expansion or contraction of blood flow, its diameter can be designed to be slightly smaller than that of a conventional cannula 300', thus reducing the difficulty of implanting the blood pump 10. Additionally, when the blood pump 10 is used as a right ventricular interventional pump, its interventional path is from the inferior or superior vena cava, right atrium, right ventricle to the pulmonary artery. This interventional path is characterized by its short length, numerous bends, and complex internal structure. Because the main tube segment 330 of the cannula 300 of the blood pump 10 in this application is more flexible than that of a conventional cannula 300', the blood pump 10 can more easily adapt to changes in this interventional path, effectively reducing the difficulty of advancement. Moreover, since the main tube segment 330 of the cannula 300 does not have an elastic stent, it is not necessary to shape the main tube segment 330 of the cannula 300 into a curved shape.
[0056] See Figure 3 and Figure 4For both the proximal tube 100 and the distal tube 200, they are metal tubes with high rigidity and are not easily deformed. This allows the proximal tube 100 to support the first segment 310 of the cannula 300, and the distal tube 200 to support the second segment 320 of the cannula 300. Specifically, the first segment 310 is fitted onto the proximal tube 100 and can be fixed to it using methods such as bonding or interference fit. The second segment 320 is fitted onto the distal tube 200 and can be fixed to it using methods such as bonding or interference fit. Considering that bonding can ensure a strong connection and reduce the manufacturing difficulty of the blood pump 10, it can be given priority.
[0057] Optionally, such as Figure 3 As shown, the outer peripheral surface of the proximal end of the proximal tube 100 may be provided with multiple first adhesive grooves 102 along the axial direction of the blood pump 10. The first adhesive grooves 102 are used to hold adhesive to bond the proximal tube 100 to the first tube segment 310 of the cannula 300; as shown Figure 3 As shown, the outer peripheral surface of the proximal end of the distal tube 200 may be provided with multiple rings of second adhesive grooves 202 along the axial direction of the blood pump 10. The second adhesive grooves 202 are used to hold adhesive to bond the distal tube 200 to the second tube segment 320 of the cannula 300.
[0058] See Figure 12 For the cannula 300, the flexible membrane (denoted as the main flexible membrane 331) of the main pipe section 330 of the cannula 300 can be a single-layer flexible membrane. Theoretically, the main flexible membrane of the main pipe section 330 of the cannula 300 can also be multi-layered flexible membranes. However, the more layers there are, the weaker the radial expansion and contraction ability of the cannula 300 will be. Therefore, the number of layers of the cannula 300 can be set according to the material characteristics of the cannula 300 and the magnitude of the blood flow pressure to ensure that the cannula 300 can perform corresponding radial expansion and contraction with changes in blood flow.
[0059] The cannula 300 is cylindrical, and its inner circumferential surface smoothly transitions with the inner circumferential surfaces of the proximal cannula 100 and the distal cannula 200 to form a cylindrical surface; the outer circumferential surface of the cannula 300 smoothly transitions with the outer and inner circumferential surfaces of the proximal cannula 100 and the distal cannula 200 to form a cylindrical surface, which can reduce the chance of thrombosis.
[0060] It is understandable that the cannula 300, except for the main tube section 330, may or may not have elastic supports. As an example, the flexible membranes of the first tube section 310 and the second tube section 320 are integrated with the flexible membrane of the main tube section 330, and neither has an elastic support. Specifically, the flexible membrane of the first tube section 310 is designated as the first end flexible membrane 311; the flexible membrane of the second tube section 320 is designated as the second end flexible membrane 321, and the first end flexible membrane 311 is integrated with the main body flexible membrane 331 and the second end flexible membrane 321. In other words, the entire cannula 300 has no elastic supports. Thus, the cannula 300 does not need multiple layers of flexible membranes to cover the elastic supports, allowing the cannula 300 to be a single-layer structure. In other words, the entire cannula 300 has only a single layer of flexible membrane and is formed in one piece, thereby reducing the manufacturing steps of the cannula 300 and improving production efficiency.
[0061] See Figure 13 Furthermore, the flexible membrane of the main tube segment 330 (i.e., the main flexible membrane 331) has a first membrane wall thickness H1; the flexible membranes of the first tube segment 310 and the second tube segment 320 (i.e., the first end flexible membrane 311 and the second end flexible membrane 321) have a second membrane wall thickness H2, and the second membrane wall thickness H2 is greater than the first membrane wall thickness H1, i.e., H2 > H1. This arrangement can also increase the strength of the first tube segment 310 and the second tube segment 320, making the first tube segment 310 and the second tube segment 320 less prone to deformation, thus less likely to be washed away by blood, increasing the strength of the connection between the first tube segment 310 and the proximal tube 100, and the strength of the connection between the second tube segment 320 and the distal tube 200, preventing the first tube segment 310 and the second tube segment 320 from loosening and falling off. In addition, the flexibility of the main tube segment 330 of the cannula 300 is better than that of the first tube segment 310 and the second tube segment 320 of the cannula 300, so that the main tube segment 330 of the cannula 300 can better adapt to the shape of the blood vessel and facilitate the push of the blood pump 10.
[0062] It is worth noting that if the first membrane wall thickness H1 of the main tube segment 330 is constant along the length of the cannula 300, then the second membrane wall thickness H2 is greater than the first membrane wall thickness H1 at any position of the main tube segment 330. If the first membrane wall thickness H1 of the main tube segment 330 varies along the length of the cannula 300, then the second membrane wall thickness H2 is greater than the maximum first membrane wall thickness H1 of the main tube segment 330.
[0063] See Figure 13 and Figure 14In one embodiment, the main tube section 330 of the cannula 300 includes a proximal end 332, a distal end 333, and a main body portion 334 located between the proximal end 332 and the distal end 333. The proximal end 332 is connected to a first tube section 310, and the distal end 333 is connected to a second tube section 320. The main body portion 334 of the main tube section 330 has a main membrane wall thickness H. 1a Both the proximal end 332 and the distal end 333 of the main pipe section 330 have an end membrane wall thickness H. 1b The end membrane wall thickness H of at least one of the proximal end 332 and the distal end 333 1b Greater than the thickness H of the main membrane wall 1a H 1b >H 1a In other words, the inner or outer diameter of the main tube section 330 varies along the axial direction, causing the first membrane wall thickness H1 to vary along the length of the insertion tube 300. In this case, the second membrane wall thickness H2 of the first tube section 310 and the second tube section 320 can be greater than or equal to the end membrane wall thickness H. 1b .
[0064] For the proximal end 332 of the main tube segment 330, since the entire main tube segment 330 lacks an elastic support, the stiffness of the proximal end 332 differs significantly from that of the proximal tube 100, potentially leading to bending at the proximal end 332. Taking a right ventricular interventional blood pump as an example, during operation, the impeller 400 of the blood pump 10 is a high-pressure zone. If the proximal end 332 of the tube segment 330 bends, blood will have difficulty flowing from the impeller 400 into the cannula 300, and the blood trapped within the proximal tube 100 is prone to thrombosis. Therefore, by adjusting the end membrane wall thickness H of the proximal end 332... 1b Set to be greater than the thickness H of the main membrane wall 1a This can increase the strength of the proximal end 332, making it less prone to bending and preventing blood from congesting and forming a thrombus.
[0065] For the distal end 333 of the main tube segment 330, since the entire main tube segment 330 lacks an elastic support, the distal end 333 of the main tube segment 330 is more prone to expansion when blood flows along the Y+ direction (see...). Figure 4 When the membrane is injected into the distal tube 200, the distal end 333 expands more easily and spreads open the second tube segment 200 connected to it, increasing the inner diameter of the second tube segment 200. This makes the second tube segment 320 easier to loosen and detach from the distal tube 200. Therefore, by increasing the end membrane wall thickness H of the distal end 333... 1b Set to be greater than the thickness H of the main membrane wall 1aThis can increase the strength of the distal end 333, making it less prone to excessive expansion and deformation, and preventing the distal end 333 from expanding and opening up the second pipe section 200, causing the inner diameter of the second pipe section 200 to increase, thereby preventing the second pipe section 200 from loosening and falling off.
[0066] It is understood that in the above embodiments, the axial lengths of the proximal end 332 and the distal end 333 only account for a small portion of the axial length of the main pipe section 330. Therefore, the increased thickness of the proximal end 332 and the distal end 333 will not have a significant impact on the overall expansion of the main pipe section 330, and will not affect the large flow of blood passing through the main pipe section 330 when the blood volume increases. The specific axial lengths of the proximal end 332 and the distal end 333 can be reasonably configured according to the actual axial length of the main pipe section 330.
[0067] See Figure 15 In another embodiment, unlike the above embodiments, at least one of the first segment 310 and the second segment 320 of the cannula 300 has an elastic support, which is embedded in the flexible membrane of the corresponding segment. For example, the elastic support of the first segment 310 is a first elastic support 312, which is embedded in the first end flexible membrane 311. The elastic support of the second segment 320 is a second elastic support 322, which is embedded in the second end flexible membrane 321.
[0068] By configuring the first tube segment 310 and / or the second tube segment 320 as a multi-layer structure consisting of at least a flexible membrane and an elastic stent, the strength of the first tube segment 310 and the second tube segment 320 can be increased, making the first tube segment 310 and the second tube segment 320 less prone to deformation and thus less likely to be flushed away by blood. This increases the strength of the connection between the first tube segment 310 and the proximal tube 100, as well as the strength of the connection between the second tube segment 320 and the distal tube 200, preventing the first tube segment 310 and the second tube segment 320 from loosening and falling off.
[0069] like Figure 2 and Figure 4As shown, in some embodiments, the cannulation assembly further includes a support wire 500 disposed within the fluid flow channel 301. The support wire 500 has a first end 510 and a second end 520 opposite to each other. The first end 510 is fixed to the proximal tube 100, and the second end 520 is fixed to the distal tube 200. Because the main tube segment 310 of the cannulation 300 does not have an elastic support, the main tube segment 310 is more flexible than a conventional cannulation 300', thus making it less likely for the main tube segment 310 to transmit thrust between the proximal tube 100 and the distal tube 200 during the process of pushing the blood pump 10 into the patient's body. Therefore, by providing a support wire 500 in the fluid flow channel 301 of the cannula 300, which connects the proximal tube 100 and the distal tube 200, the support wire 500 can transmit the pushing force between the proximal tube 100 and the distal tube 200 when the blood pump 10 is pushed from outside the body along the interventional path to the target position inside the body, thus providing support and facilitating the pushing of the blood pump 10. This ensures that the cannula 300 itself can expand and contract without affecting the pushing of the blood pump 10.
[0070] The support wire 500 can be a nickel-titanium wire or other metal wire with a certain degree of flexibility, which can be bent to adapt to the shape of the blood vessel. Of course, the support wire 500 may not be provided. In other embodiments, the fluid flow channel 301 of the cannula 300 may not have a support wire 500; when implanting the blood pump 10 into the patient's body, a flexible auxiliary tube can be first fitted over the cannula 300, with its two ends fitted onto the proximal tube 100 and the distal tube 200, respectively. Then, the blood pump 10 is pushed into the body, and after reaching the target position, the auxiliary cannula can be withdrawn.
[0071] like Figures 4 to 6 As shown, in one embodiment, the proximal tube 100 has a proximal section for accommodating the impeller 400 and a distal section located at one end of the proximal section. The distal section has an internally perforated mounting bracket 130 with a first insertion hole 130a. The first end 510 of the support wire 500 is inserted into the first insertion hole 130a. Inserting the first end 510 of the support wire 500 into the first insertion hole 130a of the mounting bracket 130 facilitates the fixation of the support wire 500 to the mounting bracket 130.
[0072] Regarding the structure of the mounting bracket 130, the mounting bracket 130 can be hollow, with holes formed in the hollow portion of the mounting bracket 130, allowing blood to pass through the holes in the hollow portion of the mounting bracket 130. It should be noted that, as... Figure 5As shown, the mounting bracket 130 is located on the side of the impeller 400 near the liquid flow channel 301. The mounting bracket 130 and the impeller 400 are spaced apart along the axial direction of the proximal pipe 100 by a first axial distance P. The first axial distance P can prevent the impeller 400 from interfering with the mounting bracket 130 when rotating. It is understood that the size of the first axial distance P should be reasonably configured according to the axial length of the proximal pipe 100 and the impeller 400, and no specific limitation is set here.
[0073] The specific shape and structure of the mounting bracket 130 can be customized according to requirements. For example, such as... Figures 5 to 7 As shown, the mounting bracket 130 includes a base 131 and a plurality of support arms 132 circumferentially along the base 131; the support arms 132 are fixedly connected to the base 131 and the proximal tube 100; after the impeller 400 is installed to the proximal section of the proximal tube 100, the impeller 400 and the base 131 of the mounting bracket 130 are axially opposite and spaced apart. The base 131 is provided with a first insertion hole 130a. At least one hole is formed between two adjacent support arms 132. The mounting bracket 130 with this structure is simple and can also ensure that blood can flow smoothly into the insertion tube 300 or the proximal tube 100 through the mounting bracket 130.
[0074] Both the base 131 and the support arm 132 can be edgeless structures, and the transition between the support arm 132 and the base 131, as well as between the support arm 132 and the inner circumferential surface of the proximal tube 100, is smooth (e.g., with rounded corners). This can reduce the probability of thrombosis. It should be noted that an edgeless structure means that there are no sharp corners at the connection between the two surfaces.
[0075] The number of support arms 132 can be set to 2 to 5 (e.g., 2, 3, 4, or 5). If there are fewer than 2, the connection strength between the mounting bracket 130 and the proximal tube 100 may not be guaranteed; if there are more than 5, it may obstruct blood flow, making it difficult for blood in the proximal tube 100 to flow smoothly into the cannula 300 or the proximal tube 100 through the mounting bracket 130. In addition, the support arms 132 can be connected to the base 131 and the proximal tube 100 by means of integral molding, bonding, etc. Considering that the integral molding method has the characteristic of high connection strength, it can be given priority.
[0076] See also Figure 5The base 131 of the mounting bracket 130 has a first surface 1311 facing the distal tube 200. The first insertion hole 130a has an inlet 130b penetrating the first surface 1311 and a support surface 130c opposite to the inlet 130b for supporting the support wire 500. The support wire 500 can be interference-fitted with the circumferential inner wall of the inlet 130b to facilitate the installation of the support wire 500 on the mounting bracket 130. The support surface 130c of the first insertion hole 130a can support the support wire 500. During the pushing process of the blood pump 10, the first end 510 of the support wire 500 abuts against the support surface 130c, so that the proximal tube 100 transmits the pushing force to the distal tube 200 through the support wire 500.
[0077] Of course, in some other embodiments, the support wire 500 is a metal wire, and a magnet is provided in the first insertion hole 130a, which can be magnetically attracted and fixed to the support wire 500. That is to say, the support wire 500 is a metal wire made of a magnetically conductive metal that can be attracted by a magnet. By limiting the support wire 500 with the first insertion hole 130a and magnetically attracting the support wire 500 with the magnet, the firmness of the first end 510 of the support wire 500 is ensured to be mounted on the mounting bracket 130.
[0078] See Figure 4 Furthermore, the base 131 of the mounting bracket 130 also has a second surface 1312 facing away from the distal tube 200. The second surface 1312 is axially spaced from the distal end of the impeller 400, and is configured as an arcuate surface convex in the direction facing away from the distal tube 200. In this way, the second surface 1312 can guide the flow of blood.
[0079] Specifically, when blood flows from the impeller 400 to the cannula 300, the blood comes into contact with the second surface 1312 and is guided by the second surface 1312 to flow into the holes around the mounting bracket 130, allowing the blood to flow smoothly into the cannula 300 from the holes. Conversely, when blood flows from the cannula 300 to the impeller 400, after passing through the holes around the mounting bracket 130, some of the blood adheres to the wall of the second surface 1312 and flows towards the central axis of the impeller 100, thus allowing this portion of the blood to flow into the impeller 100. Therefore, the second surface 1312 can guide blood flow and reduce the resistance of the mounting bracket 130 to blood flow.
[0080] It is understandable that the support wire 500 may also be adjacent to the inner wall of the cannula 300; the mounting bracket 130 may also be a protrusion on the inside of the proximal tube 100, and the first end 510 of the support wire 500 may be fixed to the protrusion.
[0081] like Figure 6 and Figure 7As shown, in some embodiments, the proximal tube 100 may include an open tube 110 and an adapter tube 120. The adapter tube 120 connects the open tube 110 and the first section 310 of the insertion tube 300. The open tube 110 has a first opening 101, a mounting bracket 130 is disposed within the adapter tube 120, and an impeller 400 is disposed at least within the open tube 110. The open tube 110 forms the proximal section of the proximal tube 100, and the adapter tube 120 forms the distal section of the proximal tube 100. The outer circumferential surface of the adapter tube 120 has a first adhesive groove 102. The adapter tube 120 is a reducing tube, which can smoothly connect the insertion tube 300 and the open tube 110 with different diameters.
[0082] The adapter tube 120 can be fixed to the open tube 110 by means of bonding, integral molding, etc. The adapter tube 120 is not necessary. The proximal tube 100 can only have the open tube 110. The open tube 110 is directly connected to the first tube segment 310 of the insertion tube 300. It is only necessary that the length of the open tube 110 is long enough to accommodate the impeller 400 and the mounting bracket 130.
[0083] In some embodiments, such as Figure 8 and Figure 9 As shown, the distal tube 200 includes a tube body 220 and an installation end 210; wherein, the tube body 220 is connected to the second tube segment 320, and the tube body 220 is provided with a second opening 201; the installation end 210 is connected to the end of the tube body 220 that is away from the insertion tube 300.
[0084] Furthermore, the mounting end 210 includes a flow guide cone 211 located within the tube body 220, the diameter of which gradually decreases in the direction from the mounting end 210 to the tube body 220. The flow guide cone 211 can guide the flow of blood, facilitating the discharge of blood from the second opening 201 or its flow into the distal tube 200.
[0085] See also Figure 8 and Figure 9 The guide cone 211 of the mounting end 210 is provided with a second insertion hole 210a, and the second end 520 of the support wire 500 is inserted into the second insertion hole 210a. Inserting the second end 520 of the support wire 500 into the second insertion hole 210a of the guide cone 211 facilitates the fixed connection between the support wire 500 and the distal tube 200.
[0086] In some embodiments, such as Figures 1 to 4 and Figure 8 As shown, the blood pump 10 also includes a non-invasive flexible element 900, which is fixedly connected to the mounting end 210. The non-invasive flexible element 900 is used to abut against tissues within the patient's body (such as the ventricular wall or arterial wall) to position the blood pump 10. See specifically... Figure 8 and Figure 9The mounting end 210 also includes a connecting seat 212, which is connected to the distal end of the guide cone 211. The connecting seat 212 is located outside the tube body 220 and is fixedly connected to the non-invasive flexible element 900. It is understood that the non-invasive flexible element 900 can be configured as a pigtail tube with a pigtail shape (e.g., Figure 1 (As shown). Alternatively, the non-invasive flexible component 900 has a flexible long axis portion 910 and a ball head 920 connected to the flexible long axis portion 910 (as shown). Figure 25 (As shown).
[0087] like Figure 10 As shown, when pushing the blood pump 10, the interventional guidewire 20 is first inserted into the patient's body, with the proximal end of the interventional guidewire 20 remaining outside the body, and then... Figure 10 As shown, the proximal end of the interventional guidewire 20 is inserted through the non-invasive flexible part 900 of the blood pump 10, then through the distal tube 200, the fluid flow channel 301 of the cannula 300, and the proximal tube 100, and finally out through the first opening 101 of the proximal tube 100, so that the blood pump 10 is fitted on the interventional guidewire 20. Then, the blood pump 10 is pushed into the patient's body along the interventional guidewire 20.
[0088] The guide cone 211 at the mounting end 210 is provided with a guide wire hole 210b for the interventional guide wire 20 to pass through, and the guide wire hole 210b communicates with the non-invasive flexible element 900. The proximal end of the interventional guide wire 20 passes through the non-invasive flexible element 900 of the blood pump 10 and can enter the distal tube 200 through the guide wire hole 210b of the guide cone 211.
[0089] To enable the support wire 500 to better direct and transmit the pushing force, the support wire 500 is positioned as close as possible to the central axis 11 of the blood pump 10. This means that the first insertion hole 130a and the second insertion hole 210a for inserting the support wire 500 are also positioned as close as possible to the central axis 11 of the blood pump 10. However, considering that the proximal end of the non-invasive flexible element 900 and the distal tube 200 are coaxially arranged, both of which are located on the central axis 11 of the blood pump 10, the interventional guide wire 20 should also be positioned as close as possible to the central axis 11 in order to allow the interventional guide wire 20 to pass smoothly from the non-invasive flexible element 900 into the guide wire hole 210b of the guide cone 211.
[0090] In this regard, such as Figure 4 , Figure 5 and Figure 9 As shown, in one embodiment, the guidewire hole 210b and the first insertion hole 130a are opposite each other along the central axis 11 of the blood pump 10, and the second insertion hole 210a is adjacent to the central axis 11 of the blood pump 10. The guidewire hole 210b and the first insertion hole 130a being opposite each other along the central axis 11 of the blood pump 10 allows the interventional guidewire 20 (see...) to be positioned so that... Figure 10The wire can be smoothly inserted from the non-invasive flexible part 900 into the guide wire hole 210b of the guide cone 211. The second insertion hole 210a is slightly offset to one side of the central axis 11 of the blood pump 10, so that the second insertion hole 210a is as close as possible to the central axis 11 of the blood pump 10, which can maintain the support wire 500 to transmit the pushing force in the axial direction better.
[0091] Of course, in another embodiment, the first insertion hole 130a can be opposite to the second insertion hole 210a along the central axis 11 of the blood pump 10, and the guide wire hole 210b is adjacent to the central axis 11 of the blood pump 10. The first insertion hole 130a and the second insertion hole 210a being opposite each other along the central axis 11 of the blood pump 10 facilitates the insertion and installation of the support wire 500; while the guide wire hole 210b is slightly offset to one side of the central axis 11 of the blood pump 10, making the guide wire hole 210b as close as possible to the central axis 11 of the blood pump 10, thus minimizing its impact on the passage of the interventional guide wire 20.
[0092] like Figure 10 As shown, in some embodiments, considering that the proximal end of the interventional guidewire 20 may become entangled with the support wire 500 in the fluid flow channel 301 after being inserted into the cannula 300, the cannula 300 can also be made of a transparent flexible material to reduce the occurrence of this situation, thereby allowing the interior of the cannula 300 to be seen. Therefore, when the blood pump 10 is implanted, the position of the interventional guidewire 20 inside the cannula 300 can be observed, allowing for timely adjustment of the position of the interventional guidewire 20 within the fluid flow channel 301 to avoid entanglement between the interventional guidewire 20 and the support wire 500; simultaneously, it also facilitates the calibration of the interventional guidewire 20 passing through the hole in the mounting bracket 130.
[0093] like Figure 11 As shown, in some embodiments, the support wire 500 has a first diameter D1, and the interventional guide wire 20 has a second diameter D2, wherein the first diameter D1 is greater than or equal to the second diameter D2, i.e., D1 ≥ D2. This configuration ensures that the support wire 500 has sufficient strength to transmit the pushing force between the proximal tube 100 and the distal tube 200. It is understood that the first diameter D1 should not be too large. If the first diameter D1 is too large, it will increase the stiffness of the support wire 500, thereby increasing the difficulty of bending the cannula 300. Therefore, the first diameter D1 should not be too large, and can be reasonably configured according to the actual bending degree required by the cannula 300.
[0094] Optionally, the first diameter D1 is less than or equal to 1.5 times the second diameter D2, i.e., D1 ≤ 1.5D2. The value of D1 can be, but is not limited to, 1.1D2, 1.2D2, 1.3D2, 1.4D2, etc. This setting ensures that the stiffness of the support wire 500 is not too high, ensuring that the support wire 500 has sufficient strength, while also making it less difficult for the insertion tube 300 to bend.
[0095] like Figure 1 and Figure 4 As shown in the previous description, since the cannula 300 does not have an elastic stent, it may bend at its proximal end. Taking a right ventricular interventional blood pump as an example, during operation, the impeller 400 of the blood pump 10 is a high-pressure area. If the proximal end of the cannula 300 bends, blood will have difficulty flowing from the impeller 400 into the cannula 300, and the blood will be blocked in the proximal tube 100, easily forming a thrombus. In addition to increasing the membrane wall thickness at both ends of the cannula 300 as described above, another embodiment to solve this problem is provided below.
[0096] like Figure 17 and Figure 18 As shown, in this embodiment, the blood pump 10 further includes a first rectifier tube 610; the first rectifier tube 610 is disposed at the proximal end of the cannula 300 to increase the strength of the proximal end of the cannula 300. Therefore, by adding the first rectifier tube 610 at the proximal end of the cannula 300 to strengthen the proximal end of the cannula 300, bending of the proximal end of the cannula 300 can be avoided, thereby preventing the formation of thrombi at this location.
[0097] like Figure 18 , Figure 19 and Figure 21 As shown, specifically, the first rectifier tube 610 includes a first rectifier section 612, which is fixedly sleeved on the outer periphery of the proximal end 332 of the main pipe section 330. This can strengthen the proximal end 332 of the main pipe section 330 to a certain extent, preventing bending at the proximal end 332 position and thus preventing the formation of thrombi at this position.
[0098] Furthermore, the first rectifier tube 610 also includes a first fixing section 611 connected to the first rectifier segment 612, the first fixing section 611 being fixedly fitted onto the outer periphery of the first pipe segment 310. The first rectifier segment 612 can clamp the first pipe segment 310 and the proximal pipe 100 to strengthen the connection between the first pipe segment 310 and the proximal pipe 100 and prevent the first pipe segment 310 from loosening and falling off. The first fixing section 311 and the first rectifier segment 612 are integrally formed.
[0099] like Figure 17 and Figure 18 As shown, in some embodiments, the blood pump 10 further includes a second rectifier tube 620, which is disposed at the distal end of the cannula 300 to improve the distal strength of the cannula 300. Taking a right ventricular interventional blood pump as an example, blood flows along... Figure 18The Y+ direction scouring of the distal end of the cannula 300 may cause it to over-expand, increasing its diameter and making it more prone to loosening. Therefore, by adding a second rectifier tube 620 to the distal end of the cannula 300, the strength of the distal end is increased, making it less prone to radial expansion and thus preventing the distal end of the cannula 300 from loosening and falling off the distal tube 200.
[0100] like Figure 18 , Figure 20 and Figure 22 As shown, specifically, the second rectifier tube 620 includes a second rectifier section 621, which is fixedly sleeved on the outer periphery of the distal end 333 of the main pipe section 330. This can strengthen the distal end 333 of the main pipe section 330 to a certain extent, prevent the distal end 333 from excessively expanding and stretching the second pipe section 320, and thus prevent the second pipe section 320 from loosening and falling off.
[0101] Furthermore, the second rectifier tube 620 also includes a second fixing section 622 connected to the second rectifier section 621, the second fixing section 622 being fixedly fitted onto the outer periphery of the second tube section 320. The second fixing section 622 can tighten the second tube section 320 and the distal tube 200 to enhance the firmness of the connection between the second tube section 320 and the distal tube 200, preventing the second tube section 320 from loosening and falling off. The second fixing section 622 and the second rectifier section 621 are integrally formed. It is understandable that both the first rectifier tube 610 and the second rectifier tube 620 are individually manufactured components and are both flexible. During assembly, the first rectifier tube 610 and the second rectifier tube 620 are first fitted onto both ends of the insertion tube 300 and fixedly connected to it. Then, both ends of the insertion tube 300 are connected and fixed to the proximal tube 100 and the distal tube 200, respectively. Both the first rectifier tube 610 and the second rectifier tube 620 can be connected and fixed to the insertion tube 300 by adhesive bonding or heat fusion welding.
[0102] Optionally, the hardness of the first rectifier tube 610 is greater than the hardness of the insertion tube 300; and / or, the hardness of the second rectifier tube 620 is greater than the hardness of the insertion tube 300, which can effectively improve the deformation resistance of the proximal and distal ends of the insertion tube 300. Of course, in other embodiments, the first rectifier tube 610 and the second rectifier tube 620 can be made of the same material as the insertion tube 300, that is, the deformation resistance of the proximal and distal ends of the insertion tube 300 can be increased by increasing the membrane wall thickness at both ends of the insertion tube 300.
[0103] As an example, such as Figure 19As shown, the first rectifier tube 610 includes a metal spring layer 601 and a flexible membrane layer 602 disposed outside the metal spring layer 601. This structure gives the first rectifier tube 610 a certain degree of flexibility, allowing it to bend to adapt to the shape of the blood vessel. The flexible membrane layer 602 can be made of a flexible material such as TPU.
[0104] The structure of the second rectifier tube 620 can be the same as that of the first rectifier tube 610, for example, Figure 20 As shown, the second rectifier tube 620 also includes a metal spring layer 601 and a flexible film layer 602 disposed outside the metal spring layer 601. Of course, in some other embodiments, the structure of the second rectifier tube 620 may differ from that of the first rectifier tube 610.
[0105] like Figure 18 As shown, in some embodiments, the first tube segment 310 and the second tube segment 320 both have a first length L1 along the axial direction of the cannula 300, the first rectifier section 612 has a second length L2 along the axial direction of the cannula 300, and the main tube segment 330 has a third length L3 along the axial direction of the cannula 300; then L1≤L2≤3L1; and / or, 3%<L2 / L3<10%. This configuration can prevent the second length L2 of the first rectifier section 612 from being too short, thereby ensuring that the proximal and distal ends of the cannula 300 have sufficient strength, preventing the proximal end of the cannula 300 from "folding" and the distal end of the cannula 300 from falling off the distal tube 200; it can also prevent the second length L2 of the first rectifier section 612 from being too long, reducing the influence of the first rectifier section 612 on the radial expansion and contraction of the main tube segment 330, thereby reducing the limitation of the radial dimension of the cannula 300 on blood flow and improving the efficiency of blood pumping.
[0106] It is understandable that the second length L2 of the first rectifier section 612 is the same as the axial length of the proximal end 332 of the main pipe section 330 of the cannula 300, and the second length L2 of the second rectifier section 622 is the same as the axial length of the distal end 333 of the main pipe section 330 of the cannula 300. The proportional relationship between the first length L1, the second length L2, and the third length L3 can be set according to specific needs, such as L2=L1, L2=2L1, L2=3L1, etc., and L2 / L3=3.1%, 4%, 5%, 6%, 7%, 8%, 9%, 9.9%, etc.
[0107] See Figure 23 and Figure 24In some embodiments, a support frame 510 is provided on the outer peripheral surface of the support wire 500. The support frame 510 is located in the middle of the support wire 500, and the outer peripheral surface of the support frame 510 is radially spaced from the inner wall surface of the main tube section 330 by a first radial distance D3. Because the outer peripheral surface of the support frame 510 and the inner wall surface of the main tube section 330 have the first radial distance D3, the support frame 510 allows the cannula 300 to bend within a certain range without excessive bending. During the process of the blood pump 10 pushing the cannula 300 into the patient's body, if the cannula 300 bends excessively to adapt to the shape of the blood vessel, the support frame 510 can support the main body 334 of the main tube section 330 from the middle of the support wire 500, thereby preventing the main body 334 from bending and thus preventing the main tube section 330 from collapsing and blocking the fluid flow channel 301.
[0108] Understandably, the support frame 510 should be hollow, with holes forming in the hollow areas to allow blood to flow smoothly through the fluid channel 301. There are various design options for the shape and structure of the support frame 510. For example, the support frame 510 can be a support ring 511, which has an annular support portion 511a surrounding the support wire 500, and a support rib 511b connecting the annular support portion 511 and the support wire 500. The annular support portion 511a is spaced apart from the inner wall surface of the main pipe section 330. Another example is that the support frame 510 can be a support mesh 512, which is a grid shape and loops around the outer periphery of the middle part of the support wire 500. Only the outer peripheral surface of the support frame 510 needs to be spaced apart from the inner wall surface of the main pipe section 330. Either the support mesh 512 or the support ring 511 can be used.
[0109] It is worth noting that the middle part of the support wire 500 refers to the position that roughly bisects the axial length of the support wire 500. The support frame 510 can also be placed at other locations on the main pipe section 330 that are prone to significant bending. The support frame 510 can be elastic or inelastic. When the support frame 510 is inelastic, its axial dimension should be designed to be shorter to avoid affecting the bending deformation of the cannula 300. There can be one or more support frames 510. If there are multiple support frames 510, they should be spaced apart along the length of the support wire 500. Support frames 510 are not mandatory. The number of support frames 510 and their total axial length can be rationally designed based on the axial length of the main pipe section 330 to avoid affecting the proper bending and radial deformation of the main pipe section 330.
[0110] Because there is a first radial distance D3 between the outer peripheral surface of the support frame 510 and the inner wall surface of the main pipe section 330, the support frame 510 is less likely to affect the small-amplitude expansion and contraction of the main pipe section 330 along its radial direction. The size of the first radial distance D3 can be reasonably designed according to the actual size of the inner diameter of the insertion tube 300. Optionally, the first radial distance D3 is less than or equal to 1 / 4 times the inner diameter D4 of the main pipe section 330, i.e., D3 ≥ 1 / 4 D4. Optionally, D3 ≤ 1 / 2 D4. Since D3 ≥ 1 / 4 D4, it can be ensured that when the main pipe section 330 undergoes normal small-amplitude expansion and contraction along its radial direction, the support frame 510 will not abut against the inner wall surface of the main pipe section 330, avoiding the support frame 510 affecting the radial deformation of the main pipe section 330; while when the main pipe section 330 undergoes excessive bending and the inner wall surface of the main pipe section 330 touches the support frame 510, the support frame 510 can support the main pipe section 330, thereby preventing the main pipe section 330 from collapsing.
[0111] When blood pump 10 is a right ventricular interventional pump, if the blood pressure in the pulmonary artery is too high, and blood pump 10 continues to pump blood into the pulmonary artery at a high flow rate, it can easily lead to pulmonary edema, pulmonary congestion, and other conditions in the patient. Therefore, in Figures 25 to 28 In the illustrated embodiment, the cannulation assembly further includes a pressure sensor 800, which includes a probe 810 and a wire 820 connected to the probe 810. The probe 810 is mounted on the mounting end 210 of the distal tube 200, and the wire 820 at least partially passes through the fluid flow channel 301 of the cannulation assembly, allowing the wire 820 to be connected to the controller of the blood pump 10 (not shown in the figure). The pressure sensor 800 can be used to detect blood pressure. After the blood pump 10 enters the pulmonary artery through the right ventricle, the distal tube 200 of the cannulation assembly is located in the pulmonary artery, so the probe 810 on the distal tube 200 can detect the blood pressure in the pulmonary artery. Therefore, by detecting the blood pressure in the pulmonary artery through the pressure sensor 800 and feeding back the detected blood pressure to the controller of the blood pump 10, the controller can control the blood pump 10 to reduce the pumped blood flow when the blood pressure is high, in order to avoid excessively high blood pressure in the pulmonary artery and thus prevent the patient from developing pulmonary edema, pulmonary congestion, or other conditions.
[0112] See Figure 28 and Figure 29It is understood that the probe 810 has a sensing surface 811. The connector 212 of the mounting end 210 has a distal surface 212a and an annular side surface 212b, with the distal surface 212a facing the non-invasive flexible component 900. The sensing surface 811 of the probe 810 can be disposed on either the distal surface 212a or the annular side surface 212b. If the sensing surface 811 of the probe 810 is disposed on the annular side surface 212b, it may come into contact with the inner wall of the pulmonary artery, causing the sensing surface 811 to inaccurately sense blood pressure. Therefore, in this embodiment, the sensing surface 811 of the pressure sensor 800 can be disposed on the distal surface 212a. Since the distal surface 212a is less likely to come into contact with the inner wall of the pulmonary artery, the sensing surface 811 located on the distal surface 212a can more accurately sense blood pressure. Optionally, the sensing surface 811 of the probe 810 is flush with the distal surface 212a.
[0113] Alternatively, the probe 810 of the pressure sensor 800 is located on the central axis 11 of the cannulation assembly, such that the sensing surface 811 of the probe 810 is located in the central region of the distal surface 212a, thus making it less likely to contact the inner wall of the pulmonary artery. Correspondingly, the non-invasive flexible member 900 is positioned on one side of the central axis 11 to avoid contact with the probe 810 of the pressure sensor 800. When the non-invasive flexible member 900 is positioned against the inner wall of the pulmonary artery, the sensing surface 811 of the probe 810 of the pressure sensor 800 is located on the side of the non-invasive flexible member 900 away from the inner wall of the pulmonary artery, making it even less likely to contact the inner wall of the pulmonary artery.
[0114] See Figure 28 , Figure 32 and Figure 33 In some embodiments, the cannulation assembly further includes a flexible sheath 700, which is fixed within the fluid flow channel 301 and has a first inner cavity 710 through which a support wire 500 passes. The flexible sheath 700 protects the support wire 500 from contact with blood. Specifically, the flexible sheath 700 is elongated, and the first inner cavity 710 extends along its length, penetrating at least one end of the flexible sheath 700 to allow the support wire 500 to be inserted. The proximal end of the flexible sheath 700 is fixed to the mounting end 210 of the distal tube 200, and the distal end of the flexible sheath 700 extends to and is fixed to the mounting bracket 130. Optionally, the proximal end of the flexible sheath 700 can also be fixed in the first insertion hole 130a of the mounting bracket 130; the distal end of the flexible sheath 700 can also be fixed in the second insertion hole 210a of the mounting end 210. Of course, in other embodiments, corresponding slots can also be provided on the outer periphery of the first insertion hole 130a and the second insertion hole 210a for insertion of the flexible sheath 700. The material of the flexible sheath 700 can be, but is not limited to, TPU material (i.e., thermoplastic polyurethane elastomer).
[0115] See also Figure 28 , Figures 31 to 33 In some embodiments, the flexible sheath 700 further has a second inner cavity 720, and the mounting bracket 130 inside the proximal tube 100 is provided with a radial channel 132a. The tube wall of the proximal tube 100 is provided with a wire passage hole 103, which communicates with the radial channel 132a and the second inner cavity 720 to allow the wire 820 of the pressure sensor 800 to pass through. Specifically, the proximal tube 100 has a mounting bracket 130 for mounting the support wire 500, and the support arm 132 of the mounting bracket 130 is provided with a radial channel 132a.
[0116] The wire 820 of the pressure sensor 800 includes a first segment 821, a second segment 822, and a third segment 823 connected together. The first segment 821 passes through the second inner cavity 720 of the flexible sheath 700, and the end of the first segment 821 away from the second segment 822 is connected to the probe 810. The second segment 822 is housed in the radial channel 132a. The third segment 823 passes through the wire hole 103 and is fixed to the outer wall of the proximal tube 100 and the motor 12. The wire 820 also includes a fourth segment 824 connected to the third segment 823, which is housed in the conduit 13.
[0117] See Figure 33 For a flexible sheath 700 having a first inner cavity 710 and a second inner cavity 720, the flexible sheath 700 has an arrangement direction along the first inner cavity 710 and the second inner cavity 720 (e.g., Figure 33 The maximum width L4 extending in the X direction is such that if the outer peripheral surface of the flexible sheath 700 is set as a cylindrical surface 704, then the diameter of the cylindrical surface 704 is the maximum width L4. That is, the radial dimension of the flexible sheath 700 is large at all points, which makes the volume of the flexible sheath 700 large. The flexible sheath 700 occupies a large space in the fluid flow channel 301, which affects the blood flow.
[0118] In view of the above, in this embodiment, the outer peripheral surface of the flexible sheath 700 is set as a non-cylindrical surface. The outer peripheral surface of the flexible sheath 700 includes a first arc surface 701, a second arc surface 702, and two side planes 703 connecting the first arc surface 701 and the second arc surface 702. The first arc surface 701 surrounds the side of the first inner cavity 710 away from the second inner cavity 720; the second arc surface 702 surrounds the side of the second inner cavity 720 away from the first inner cavity 710. This allows the dimension of the flexible sheath 700 in the X direction to be the maximum width L4, while the radial dimension of the flexible sheath 700 in other directions (such as the Z direction) is smaller than the maximum width L4. This results in a smaller volume of the flexible sheath 700 and a smaller space occupied by the flexible sheath 700 in the fluid flow channel 301, thereby increasing the blood flow rate through the fluid flow channel 301.
[0119] Optionally, both the first arc surface 701 and the second arc surface 702 are circular arc surfaces. The diameter of the conductor 820 is smaller than the diameter of the support wire 500, therefore the diameter of the second inner cavity 720 is smaller than the diameter of the first inner cavity 710. Correspondingly, the diameter of the circle containing the second arc surface 702 is also smaller than the diameter of the circle containing the first arc surface 701, thus the two side planes 703 connecting the first arc surface 701 and the second arc surface 702 are inclined planes facing each other, i.e., the two side planes 703 are not parallel. This further reduces the volume of the flexible sheath 700.
[0120] Of course, in other embodiments, an axial channel may be provided in the wall of the cannula 300, and the wire 820 of the pressure sensor 800 may pass through the axial channel.
[0121] See Figures 1 to 4 This application also provides a blood pump 10, which includes an impeller 400 and a cannulation assembly; the specific structure of the cannulation assembly is as described in the above embodiments; the impeller 400 is rotatably disposed on the proximal tube 100 of the cannulation assembly. Since the blood pump 10 of this application adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here.
[0122] The blood pump 10 can be a left ventricular interventional pump or a right ventricular interventional pump. When the blood pump 10 is a right ventricular interventional pump, the first opening 101 is the blood inlet and the second opening 201 is the blood outlet. During delivery, the blood pump 10 is pushed from the right ventricle to the pulmonary artery, so that the main tube segment 330 of the cannula 300 crosses the pulmonary valve, the first opening 101 is located in the right ventricle, and the second opening 201 is located in the pulmonary artery. When the blood pump 10 is a left ventricular interventional pump, the first opening 101 is the blood outlet and the second opening 201 is the blood inlet. During delivery, the blood pump 10 is pushed from the aorta to the left ventricle, so that the main tube segment 330 of the cannula 300 crosses the aortic valve, the second opening 201 is located in the left ventricle, and the first opening 101 is located in the aorta.
[0123] See Figures 1 to 4 In some embodiments, the blood pump 10 further includes a motor 12. The distal end of the motor 12 is fixedly connected to the proximal tube 100, and the shaft of the motor 12 is fixedly connected to the impeller 400, enabling the motor 12 to drive the impeller 400 to rotate. The blood pump 10 also includes a conduit 13, the distal end of which is fixedly connected to the proximal end of the motor 12. The inner cavity of the conduit 13 can accommodate flushing lines of the blood pump 10, wires 820 of the sensor 800, and other wires.
[0124] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0125] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.
Claims
1. A cannula assembly, characterized in that, The cannula assembly comprises: a proximal tube provided with a first opening; a distal tube provided with a second opening, one of the first opening and the second opening being a blood inlet and the other being a blood outlet; a cannula having a flow channel communicating the first opening and the second opening; the cannula has a first tube segment, a second tube segment and a main tube segment between the first tube segment and the second tube segment; the first tube segment is fixedly connected with the proximal tube; the second tube segment is fixedly connected with the distal tube; the first tube segment, the main tube segment and the second tube segment all have flexible membranes, and the main tube segment does not have an elastic support; and a support wire provided in the flow channel, the support wire having opposite first and second ends, the first end being fixedly connected with the proximal tube and the second end being fixedly connected with the distal tube, the support wire being capable of transmitting a pushing force between the proximal tube and the distal tube.
2. The cannula assembly of claim 1, wherein, The proximal tube has a proximal segment for accommodating an impeller and a distal segment close to the distal tube, an inner portion of the distal segment being provided with a hollow mounting bracket; the first end of the support wire is fixedly connected with the mounting bracket.
3. The cannula assembly of claim 2, wherein, The mounting bracket is located on a side of the impeller close to the flow channel, and the mounting bracket and the impeller are spaced apart along an axial direction of the proximal tube.
4. The cannula assembly of claim 2, wherein, The mounting bracket is provided with a first insertion hole in which the first end of the support wire is inserted; the cannula assembly further comprises at least one of the following features: The mounting bracket has a first surface facing the distal tube, the first insertion hole has a hole entrance penetrating through the first surface, and a support surface opposite to the hole entrance and used for supporting the support wire; The mounting bracket has a second surface facing away from the distal tube, the second surface is capable of being spaced apart from a distal end of the impeller along an axial direction of the impeller, and the second surface is provided as an arc surface protruding away from the distal tube; The proximal tube comprises an open tube and an adapter tube, the adapter tube connects the second tube segment and the open tube, the open tube is provided with the first opening and is capable of accommodating the impeller, and the mounting bracket is arranged in the adapter tube.
5. The cannula assembly of claim 2, wherein, The mounting bracket is provided with a first insertion hole in which the first end of the support wire is inserted; the distal tube comprises a tube body portion and a mounting end portion; the tube body portion is connected with the second tube segment of the cannula, and the tube body portion is provided with the second opening; the mounting end portion is connected to an end of the tube body portion away from the cannula, the mounting end portion is provided with a second insertion hole in which the second end of the support wire is inserted.
6. The cannula assembly of claim 5, wherein, The mounting end portion is further provided with a guide wire hole through which an intervention guide wire passes; the first insertion hole and the second insertion hole are both located on a central axis of the cannula assembly, and the guide wire hole is adjacent to the central axis of the cannula assembly; Alternatively, the guide wire hole and the first insertion hole are both located on the central axis of the cannula assembly, and the second insertion hole is adjacent to the central axis of the cannula assembly.
7. The cannula assembly of any one of claims 1 to 6, wherein, The cannula assembly further comprises at least one of the following features: The support wire is a metal wire, a magnet is arranged in the first jack, and the magnet can be magnetically fixed with the metal wire; The support wire is provided with a support frame on the outer circumferential surface, the support frame is located at the middle part of the support wire, the outer circumferential surface of the support frame is spaced from the inner wall surface of the main pipe section along the radial direction, and the first radial spacing is provided therebetween, the first radial spacing is greater than or equal to 1 / 4 times of the inner diameter of the main pipe section; The cannula assembly further comprises a flexible sheath, the flexible sheath is arranged in the liquid flow channel, and the flexible sheath has a first inner cavity, and the support wire is arranged in the first inner cavity.
8. The cannula assembly of any of claims 1 to 6, wherein, The main pipe section of the cannula comprises a proximal end part, a distal end part and a main body part located between the proximal end part and the distal end part, the proximal end part is adjacent to the first pipe section, and the distal end part is adjacent to the second pipe section; and The cannula assembly further comprises a first rectifier pipe, the first rectifier pipe comprises a first rectifier section, and the first rectifier section is fixedly sleeved on the outer circumference of the proximal end part; And / or, the cannula assembly further comprises a second rectifier pipe, the second rectifier pipe comprises a second rectifier section, and the second rectifier section is fixedly sleeved on the outer circumference of the distal end part.
9. The cannula assembly of claim 8, wherein, The cannula assembly at least further comprises one of the following features: The first rectifier pipe further comprises a first fixed section connected with the first rectifier section, and the first fixed section is fixedly sleeved on the outer circumference of the first pipe section; The second rectifier pipe further comprises a second fixed section connected with the second rectifier section, and the second fixed section is sleeved on the outer circumference of the second pipe section.
10. The cannula assembly of claim 8, wherein, The first pipe section and the second pipe section each have a first length L1 in the axial direction of the cannula, the first rectifier section or the second rectifier section has a second length L2 in the axial direction of the cannula, and the main pipe section has a third length L3 in the axial direction of the cannula; wherein, L1≤L2≤3L1; and / or, 0.03 11. The cannula assembly of claim 8, wherein, The first rectifier pipe and the second rectifier pipe each comprise a metal spring layer and a flexible film layer arranged outside the metal spring layer.
12. The cannula assembly of any of claims 1 to 6, wherein, The main pipe section is tubular in a natural state; the cannula assembly at least further comprises one of the following features: The flexible film of the main pipe section has a first film wall thickness, the flexible films of the first pipe section and the second pipe section have a second film wall thickness, and the second film wall thickness is greater than the first film wall thickness; The main pipe section comprises a proximal end part, a distal end part and a main body part located between the proximal end part and the distal end part, the main body part has a main body film wall thickness, and at least one of the proximal end part and the distal end part has an end part film wall thickness, the end part film wall thickness is greater than the main body film wall thickness; The material of the flexible film is TPU material.
13. The cannula assembly of any of claims 1 to 6, wherein, The first pipe section has an elastic support embedded in the flexible film of the first pipe section; and / or, the second pipe section has an elastic support embedded in the flexible film of the second pipe section.
14. The cannula assembly of claim 1, wherein, The proximal pipe and the distal pipe are both metal pipes.
15. A blood pump, characterized in that, The blood pump comprises an impeller and the cannula assembly according to any one of claims 1 to 14; wherein the impeller is rotatably arranged in the proximal pipe of the cannula assembly.
16. The blood pump of claim 15, wherein, The support wire of the cannula assembly has a first diameter, and the blood pump further comprises an interventional guide wire capable of passing through the flow channel of the cannula assembly, the interventional guide wire having a second diameter, the first diameter being greater than or equal to the second diameter.
17. The blood pump of claim 15, wherein, The blood pump further comprises a motor, a distal end of the motor being fixedly connected with the proximal tube, and a rotating shaft of the motor being connected with the impeller to drive the impeller to rotate.