Blood-pumping drive mechanism of blood pump, blood pump and ventricular assist system

Abstract

The application relates to a blood pumping driving mechanism of a blood pump, the blood pump and a ventricular assist system. The blood pumping driving mechanism comprises a paddle assembly and a driving assembly; the paddle assembly has a first mode and a second mode, the maximum radial dimension of the paddle assembly in the first mode is greater than that in the second mode; the driving assembly can drive the paddle assembly to reciprocate axially to switch the paddle assembly between the first mode and the second mode, so that the paddle assembly can perform a blood pumping operation. The blood pumping driving mechanism can effectively reduce the shearing force on blood cells, thereby greatly eliminating the risk of hemolysis, and the clinical application time and stability of the product are greatly improved, and the effects of low-frequency operation and high blood perfusion can be realized.

Description

Technical Field

[0001] This application relates to the field of medical device technology, and in particular to a blood pumping drive mechanism, a blood pump, and a ventricular assist system. Background Technology

[0002] An interventional catheter pump, also known as a blood pump, is typically implanted through a blood vessel into the ventricle of a patient's heart to assist the heart in pumping blood from the ventricle to the arteries, thus supporting the patient's blood circulation. A traditional blood pump consists of a pump housing, impeller, motor, and catheter. The motor is located between the pump housing and the catheter. The impeller, acting as the pumping drive mechanism, rotates within the pump housing under the motor's influence, drawing blood into the pump housing through the inlet and out through the outlet.

[0003] However, the shearing force generated when the impeller rotates at high speed can damage red blood cells, resulting in potential hemolysis. The longer the impeller runs, the greater the side effects and the higher the incidence of complications. Summary of the Invention

[0004] Therefore, it is necessary to provide a blood pumping drive mechanism, a blood pump, and a ventricular assist system to address the aforementioned technical problems.

[0005] A blood pumping drive mechanism for a blood pump, comprising:

[0006] A blade assembly having a first form and a second form, wherein the maximum radial dimension of the blade assembly in the first form is greater than the maximum radial dimension in the second form;

[0007] The drive component is capable of driving the blade assembly to reciprocate axially and extend and retract, so that the blade assembly alternately switches between the first mode and the second mode, thereby enabling the blade assembly to perform a blood pumping operation.

[0008] In one embodiment, the blade assembly includes a plurality of blades connected sequentially from near to far, wherein in the first configuration, each blade is deployed, and in the second configuration, each blade is retracted.

[0009] In one embodiment, the maximum radial dimension of the plurality of blades in the first configuration decreases sequentially along the pumping direction.

[0010] In one embodiment, the blade includes a closed section and a hollow section connected together, the closed section and the hollow section being arranged sequentially along the pumping direction, and the radial dimension of the connection between the closed section and the hollow section being the largest.

[0011] In one embodiment, the radial dimension of the closed segment gradually increases along the pumping direction in both the first and second forms, and the radial dimension of the hollow segment gradually decreases along the pumping direction in both the first and second forms.

[0012] In one embodiment, the closed segment includes a first skeleton and a flow-blocking membrane, the flow-blocking membrane being applied to the first skeleton, and the first skeleton being connected to the perforated segment; and / or,

[0013] The hollow section includes a second skeleton, which is connected to the closed section.

[0014] In one embodiment, the first frame is made of shape memory material, and when the first frame is in its initial state, the blades are in the first shape; and / or,

[0015] The second frame is made of shape memory material, and when the second frame is in its initial state, the blades are in the first shape.

[0016] In one embodiment, the blade assembly further includes at least one connecting pipe disposed between two adjacent blades or at the proximal end of the blade on the nearest side.

[0017] In one embodiment, the drive assembly includes an inner tube and an outer tube; the distal end of the outer tube is connected to the nearest blade; the inner tube has a connected proximal end and a distal end, the proximal end being movably fitted into the outer tube, and the distal end passing through each blade and connected to the farthest blade.

[0018] In one embodiment, the inner tube is a sodium hypochlorite tube.

[0019] In one embodiment, the blood pumping drive mechanism further has at least one of the following features:

[0020] The blood pumping drive mechanism further includes a first imaging element, which is disposed near the blade assembly.

[0021] The blood pumping drive mechanism further includes a second imaging element, which is located on the distal side of the blade assembly.

[0022] The blood pumping drive mechanism also includes a protective coating, which is disposed on the surface of the blade assembly.

[0023] A blood pump includes a pump housing, a conduit, a power mechanism, and a blood pumping drive mechanism as described in any of the preceding claims;

[0024] The pump housing has a blood inlet and a blood outlet. The conduit is located on the proximal side of the pump housing. The paddle assembly of the blood pumping drive mechanism is located in the pump housing. The proximal end of the drive assembly of the blood pumping drive mechanism is connected to the power mechanism. The power mechanism can drive the paddle assembly to reciprocate axially between the blood inlet and the blood outlet through the drive assembly.

[0025] A ventricular assist system includes a handle mechanism and a blood pump as described above, wherein the proximal end of a catheter of the blood pump is connected to the handle mechanism.

[0026] As described above, the blood pumping drive mechanism, blood pump, and ventricular assist system of the blood pumping drive mechanism can reciprocate axially under the drive of the drive component, so that it can switch between a first mode and a second mode, thereby performing blood pumping operation. The reciprocating axial extension and retraction of the blade assembly during blood pumping is equivalent to reciprocating linear motion, and the shear force generated by the reciprocating linear motion is much smaller than the shear force generated by the high-speed rotation of the impeller in existing blood pumps. In addition, the blood perfusion volume of the blood pump can be increased by appropriately increasing the maximum radial dimension of the blade assembly in the first mode, the number of blades, and the axial stroke of the blade assembly in the pump casing. This allows for a slight increase or no increase in the reciprocating axial extension and retraction frequency of the blade assembly, avoiding an excessively high reciprocating axial extension and retraction frequency. This ensures that the reciprocating axial extension and retraction frequency of the blade assembly is much lower than the high-speed rotation frequency of the blood pump impeller, which can also effectively reduce the shear force on blood cells. In summary, the blood pumping mechanism, blood pump, and ventricular assist system provided in this application can effectively reduce the shear force on blood cells, thereby greatly eliminating the risk of hemolysis. At the same time, the clinical application time and stability of the product are greatly improved, and the effect of low-frequency operation and high blood perfusion can be achieved. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of a blood pump provided in one embodiment of this application.

[0028] Figure 2 for Figure 1 The provided diagram illustrates the implantation of the blood pump in the patient's body.

[0029] Figure 3 for Figure 1 A schematic diagram of the pumping drive mechanism of the provided blood pump in the first configuration of the blade assembly.

[0030] Figure 4 for Figure 1 A schematic diagram of the blood pumping process provided.

[0031] Figure 5 for Figure 3A schematic diagram of the first and second frames of the provided blood pumping drive mechanism in the first configuration of the blade assembly.

[0032] Figure 6 for Figure 1 A schematic diagram of the structure of the blood pump as it pushes blood through the body.

[0033] The labels in the attached diagram are explained as follows:

[0034] 1. Blood pump; 10. Blood pump drive mechanism; 100. Paddle assembly; 110. Paddle; 111. Enclosed section; 1111. First frame; 1111a. First support rod; 1112. Flow-blocking membrane; 112. Hollowed-out section; 1121. Second frame; 1121a. Second support rod; 120. Connecting tube; 200. Drive assembly; 210. Inner tube; 211. Proximal end; 212. Distal end; 220. Outer tube; 300. Second imaging element; 20. Pump housing; 20a. Blood inlet; 20b. Blood outlet; 30. Catheter; 40. Power mechanism; 50. Flexible end; 60. Directional shaft; 2. Handle; M. Left ventricle; N. Aorta. Detailed Implementation

[0035] 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.

[0036] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" 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.

[0037] 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.

[0038] 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.

[0039] 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.

[0040] 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.

[0041] 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.

[0042] An interventional catheter pump, also known as a blood pump, is typically implanted through a blood vessel into the ventricle of a patient's heart to assist the heart in pumping blood from the ventricle to the arteries, thus supporting the patient's blood circulation. A traditional blood pump consists of a pump housing, impeller, motor, and catheter. The motor is located between the pump housing and the catheter. The impeller, acting as the pumping drive mechanism, rotates within the pump housing under the motor's influence, drawing blood into the pump housing through the inlet and out through the outlet.

[0043] In order to generate sufficient centrifugal force, maintain stable blood flow, and ensure blood perfusion efficiency, traditional blood pumps generally have high impeller speeds, especially axial flow blood pumps, where the impeller speed can reach approximately 7,000 to 15,000 revolutions per minute (rpm). However, when the impeller rotates at high speed, the shear force generated is greater, resulting in greater damage to red blood cells and potentially causing hemolysis. The longer the operation time, the greater the side effects and the higher the incidence of complications.

[0044] In this application, one embodiment provides a blood pumping mechanism that serves as the driving mechanism for a blood pump. This mechanism primarily provides power for blood flow, propelling the blood to achieve the pumping operation. The blood pump can be implanted into the patient's ventricle as an interventional catheter pump. Figure 1 As shown, the blood pump 1 includes a pump housing 20, a conduit 30, a power mechanism 40, and a blood pumping drive mechanism 10. The pump housing 20 is located at the distal end of the conduit 30 and has a blood inlet 20a and a blood outlet 20b. The pump housing 20 can contract or expand to adjust its radial dimensions. The power mechanism 40 can provide power to the blood pumping drive mechanism 10, so that blood flows into the pump housing 20 through the blood inlet 20a and flows out from the blood outlet 20b of the pump housing 20. Figure 1 In the diagram, the arrow X+ indicates the direction from proximal to distal; the arrow X- indicates the direction from distal to proximal. It should be noted that... Figure 1 Only the installation location of the power mechanism 40 is shown, without providing the specific structure of the power mechanism 40; furthermore, Figure 1 The straight dashed lines on the near and far sides of the pump housing 20 are only used to define the blood flow outlet 20b and blood flow outlet 20a of the pump housing 20, and have no special meaning.

[0045] like Figure 1 As shown, when blood pump 1 is a left ventricular interventional pump, the blood inlet 20a is located at the distal end of the pump housing 20, and the blood outlet 20b is located at the proximal end of the pump housing 20; Figure 2As shown, blood pump 1 pushes blood from the aorta N to the left ventricle M, with the blood inlet 20a of blood pump 1 located in the left ventricle M and the blood outlet 20b located in the aorta N; when blood pump 1 is a right ventricular interventional pump, the blood inlet 20a is located at the proximal end of the pump housing 20 and the blood outlet 20b is located at the distal end of the pump housing 20; blood pump 1 pushes blood from the right ventricle to the pulmonary artery, with the blood inlet 20a of blood pump 1 located in the right ventricle and the blood outlet 20b located in the pulmonary artery.

[0046] Specifically, such as Figure 1 and Figure 3 As shown, the blood pumping drive mechanism 10 includes a blade assembly 100 and a drive assembly 200. The blade assembly 100 is disposed within the pump housing 20 and has a first configuration and a second configuration. The maximum radial dimension of the blade assembly 100 in the first configuration is greater than that in the second configuration. The proximal end of the drive assembly 200 is connected to a power mechanism 40 and can be driven by the power mechanism 40 to reciprocate and extend axially, allowing the blade assembly 100 to alternately switch between the first and second configurations, thereby enabling the blade assembly 100 to perform blood pumping operations. Figure 4 As shown, when the drive assembly 200 compresses the paddle assembly 100 from the blood inlet 20a of the pump housing 20 towards the blood outlet 20b, the paddle assembly 100 can switch from a second form to a first form, increasing its radial dimension. This allows the paddle assembly 100 to carry blood from the blood inlet 20a to the blood outlet 20b during compression, thus pumping it into the patient's blood vessels. Conversely, when the drive assembly 200 extends the paddle assembly 100 from the blood outlet 20b towards the blood inlet 20a of the pump housing 20, the paddle assembly 100 can switch from the first form to a second form, decreasing its radial dimension. This prevents the paddle assembly 100 from carrying blood from the blood outlet 20b back to the blood inlet 20a. The paddle assembly 100 repeats these steps, i.e., through reciprocating axial extension and retraction combined with synchronous switching of its own form, achieving blood perfusion, similar to the irrigation principle of an ancient waterwheel. Figure 4 The direction of blood flow is shown when the propeller assembly 100 switches between a first mode and a second mode, wherein... Figure 4 The curved dashed arrows in the diagram represent the direction of blood flow, while the straight wide arrows represent the extension and retraction direction of the propeller assembly 100.

[0047] like Figure 3 and Figure 4As shown, the blade assembly 100 includes multiple blades 110 connected sequentially from near to far. In a first configuration, each blade 110 is deployed, while in a second configuration, each blade 110 is retracted. It should be noted that when the blade assembly 100 switches between the first and second configurations, each blade 110 opens and closes sequentially or synchronously. In the first configuration, the maximum radial dimensions of each blade 110 may be the same or different, wherein the maximum radial dimension corresponding to the blade 110 with the largest radial dimension is the maximum radial dimension of the blade assembly 100 in the first configuration. In the second configuration, the maximum radial dimensions of each blade 110 may be the same or different, wherein the maximum radial dimension corresponding to the blade 110 with the largest radial dimension is the maximum radial dimension of the blade assembly 100 in the second configuration.

[0048] Considering the processing cost and the axial dimension of the pump housing 20 of the blood pump 1, the number of blades 110 is set to 2 to 5, for example, 2, 3, 4 or 5.

[0049] like Figure 3 and Figure 4 As shown, the maximum radial dimension of the multiple blades 110 in the first configuration decreases sequentially along the pumping direction. This arrangement of the radial dimensions of the multiple blades 110 guides the flow of blood within the pump housing 20 and prevents the formation of eddies, thus improving the pumping efficiency of the blood pump 1. It should be noted that the "pumping direction" throughout this text refers to the flow direction of blood from the blood inlet 20a to the blood outlet 20b of the pump housing 20. Specifically, when the blood pump 1 is a left ventricular interventional pump, the maximum radial dimension of the multiple blades 110 in the first configuration gradually decreases from the distal to the proximal end of the pump housing 20; when the blood pump 1 is a right ventricular interventional pump, the maximum radial dimension of the multiple blades 110 in the first configuration gradually decreases from the proximal to the distal end of the pump housing 20.

[0050] The blood perfusion volume of the blood pump 1 is related to the maximum radial dimension of the impeller assembly 100 in the first configuration, the number of impellers 110, the axial stroke of the impeller assembly 100 in the pump housing 20, and the reciprocating axial extension frequency of the impeller assembly 100. Specifically, the greater the blood perfusion volume of the blood pump 1, the greater the maximum radial dimension of the impeller assembly 100 in the first configuration, the number of impellers 110, the axial stroke of the impeller assembly 100 in the pump housing 20, and the reciprocating axial extension frequency of the impeller assembly 100. In other words, when pumping blood, the blood perfusion volume of the blood pump 1 can be increased by increasing at least one of the following: the maximum radial dimension of the impeller assembly 100 in the first configuration, the number of impellers 110, the axial stroke of the impeller assembly 100 in the pump housing 20, and the reciprocating axial extension frequency of the impeller assembly 100. To avoid excessive shear force in the impeller assembly 100 due to excessive reciprocating axial extension frequency, when it is necessary to increase the blood perfusion volume of the blood pump 1, the maximum radial dimension of the impeller assembly 100 in the first state, the number of impellers 110, and the axial stroke of the impeller assembly 100 in the pump housing 20 can be appropriately increased. This can slightly increase or not increase the reciprocating axial extension frequency of the impeller assembly 100, thus avoiding excessive reciprocating axial extension frequency.

[0051] As can be seen, the blood pumping drive mechanism 10 provided in this application embodiment has a paddle assembly 100 that can reciprocate axially under the drive of the drive assembly 200, so that it can switch between a first mode and a second mode, thereby enabling blood pumping operation. The reciprocating axial extension and retraction of the paddle assembly 100 during blood pumping is equivalent to reciprocating linear motion, and the shear force generated by the reciprocating linear motion is much smaller than the shear force generated by the high-speed rotation of the impeller of the existing blood pump 1. In addition, the blood perfusion volume of the blood pump 1 can be increased by appropriately increasing the maximum radial dimension of the paddle assembly 100 in the first mode, the number of paddles 110, and the axial stroke of the paddle assembly 100 in the pump housing 20. In this way, the reciprocating axial extension and retraction frequency of the paddle assembly 100 can be increased or not increased by a small amount, avoiding the reciprocating axial extension and retraction frequency of the paddle assembly 100 being too large, so that the reciprocating axial extension and retraction frequency of the paddle assembly 100 is much lower than the high-speed rotation frequency of the impeller of the blood pump 1, which can also effectively reduce the shear force on blood cells. In summary, the blood pumping drive mechanism 10 provided in this application can effectively reduce the shear force on blood cells, thereby greatly eliminating the risk of hemolysis. At the same time, the clinical application time and stability of the product are greatly improved, and it can achieve the effect of low-frequency operation and high blood perfusion.

[0052] like Figure 4 and Figure 5As shown, in some embodiments of this application, the paddle 110 includes a connected closed section 111 and a hollow section 112, which are arranged sequentially along the pumping direction. The radial dimension is largest at the connection between the closed section 111 and the hollow section 112. The closed section 111 of the paddle 110 is mainly used to drive blood flow, while the hollow section 112 is mainly used to expand or retract the closed section 111 under the drive of the drive assembly 200. Therefore, the paddle 110 with this structure is convenient for both driving blood flow and expanding or retracting. For example, Figure 3 As shown, when the blood pump 1 is a left ventricular interventional pump, the closed section 111 is located at the distal end of the hollow section 112; when the blood pump 1 is a right ventricular interventional pump, the closed section 111 is located at the proximal end of the hollow section 112.

[0053] like Figure 3 As shown, the radial dimension of the closed section 111 gradually increases along the pumping direction in both the first and second configurations, while the radial dimension of the hollow section 112 gradually decreases along the pumping direction in both configurations. The closed section 111 and hollow section 112 of this structure resemble two opposing umbrella structures, facilitating the deployment and retraction of the paddle 110. Specifically, when the blood pump 1 is a left ventricular interventional pump, the radial dimension of the closed section 111 gradually decreases from near to far in both the first and second configurations, while the radial dimension of the hollow section 112 gradually increases from near to far in both configurations; when the blood pump 1 is a right ventricular interventional pump, the radial dimension of the closed section 111 gradually increases from near to far in both the first and second configurations, while the radial dimension of the hollow section 112 gradually decreases from near to far in both configurations.

[0054] like Figure 3 As shown, the closed section 111 includes a first skeleton 1111 and a flow-blocking membrane 1112. The flow-blocking membrane 1112 is applied to the first skeleton 1111, and the first skeleton 1111 is connected to the perforated section 112. The closed section 111 of this structure can be expanded or contracted by the deformation of the first skeleton 1111, and the flow-blocking membrane 1112 is used to directionally drive the blood flow in the pump housing 20. It can be seen that the closed section 111 of this structure is convenient for driving the blood flow and is also convenient for expansion or contraction.

[0055] like Figure 5 As shown, the first frame 1111 includes a plurality of first support rods 1111a, which are arranged sequentially along the circumference of the blade assembly 100. One end of each first support rod 1111a is connected to a hollow section 112 of the same blade 110 and a hollow section 112 of an adjacent blade 110. This first frame 1111 has a simple structure, is easy to manufacture and process, and facilitates the unfolding or folding of the closed section 111. Of course, in some other embodiments, the first frame 1111 may be configured as a mesh frame structure.

[0056] Regarding the number of first support rods 1111a, it can be set to 8 to 16, for example, 8, 9, 10, 11, 12, 13, 14, 15 or 16, without specific limitations, as long as the strength of the closed section 111 and its smooth expansion or contraction are guaranteed. Regarding the diameter of the first support rods 1111a, it can be set to 0.1mm to 0.25mm, for example, 0.1mm, 0.15mm, 0.2mm and 0.25mm, etc. This application does not impose specific limitations on this, as long as the strength of the closed section 111 and its smooth expansion or contraction are guaranteed.

[0057] The first skeleton 1111 of this structure can be laser-engraved, for example, by laser engraving a nickel-titanium alloy tube during processing. Alternatively, the first skeleton 1111 can be woven, for example, by weaving nickel-titanium wires during processing. After the first skeleton 1111 is laser-engraved or woven, it still needs to undergo heat setting, electrochemical polishing, and other processing steps.

[0058] The flow-blocking membrane 1112 can be made of biocompatible materials such as e-PTFE (expended polytetrafluoroethylene), TPU (thermoplastic polyurethanes), or nylon. This type of flow-blocking membrane 1112 has a certain degree of elasticity, allowing it to contract and expand synchronously with the first skeleton 1111 without detaching from it due to excessive changes in the radial dimensions of the first skeleton 1111, thus ensuring the normal blood pumping function of the blood pump 1.

[0059] The flow-blocking membrane 1112 can be sewn onto the first skeleton 1111. Specifically, the flow-blocking membrane 1112 can be sewn onto the first skeleton 1111 using sutures made of materials such as PET (Polyethylene terephthalate), polytetrafluoroethylene, or PP (Polypropylene). Of course, the flow-blocking membrane 1112 can also be set onto the first skeleton 1111 by heat pressing.

[0060] The flow-blocking membrane 1112 may be disposed on the inner peripheral surface of the first skeleton 1111, or on the outer peripheral surface of the first skeleton 1111, or on both the inner and outer peripheral surfaces of the first skeleton 1111. This application does not impose specific restrictions on this, as long as it can effectively block blood flow.

[0061] See also Figure 5The hollow section 112 may also include a second frame 1121, which is connected to the first frame 1111 of the closed section 111. The second frame 1121 includes multiple second support rods 1121a, which are sequentially arranged along the circumference of the blade assembly 100. One end of each second support rod 1121a is connected to the closed section 111 of the same blade 110 or the closed section 111 of an adjacent blade 110. This structure of the second frame 1121 is simple, easy to manufacture and process, and facilitates the unfolding or folding of the closed section 111. Of course, in some other embodiments, the second frame 1121 may be configured as a mesh frame structure.

[0062] Regarding the number of second support rods 1121a, it can be set to 8 to 16, for example, 8, 9, 10, 11, 12, 13, 14, 15, or 16. This application does not impose specific limitations on this, as long as the strength of the hollow section 112 and its smooth unfolding or retraction are guaranteed. Regarding the diameter of the second support rods 1121a, it can be set to 0.1mm to 0.25mm, for example, 0.1mm, 0.15mm, 0.2mm, and 0.25mm, etc., without specific limitations, as long as the strength of the hollow section 112 and its smooth unfolding or retraction are guaranteed.

[0063] The second skeleton 1121 of this structure can be laser-engraved, for example, by laser engraving a nickel-titanium alloy tube during processing. Alternatively, the second skeleton 1121 can be woven, for example, by weaving nickel-titanium wires during processing. After the second skeleton 1121 is laser-engraved or woven, it still needs to undergo heat setting, electrochemical polishing, and other processing steps.

[0064] The first frame 1111 is made of shape memory material. When the first frame 1111 is in its initial state, the propeller 110 is in a first shape. The second frame 1121 is also made of shape memory material. When the second frame 1121 is in its initial state, the propeller 110 is in a first shape. Figure 6As shown, when the blood pump 1 is inserted into the patient's body, the paddle assembly 100 is first placed into the pump housing 20, and the pump housing 20 and the paddle assembly 100 are simultaneously stretched (at this time, the paddle assembly 100 is in its second form), so that the pump housing 20 can carry the paddle assembly 100 into the sheath. When pushed into the patient's body, the pump housing 20 and the paddle assembly 100 are always in a compressed state due to the limitation of the sheath. When the blood pump 1 reaches the target position in the patient's body, the sheath is retracted, the pump housing 20 is unfolded, and at this time, the first skeleton 1111 and the second skeleton 1121 of the paddle 110 are also reset and unfolded, placed in the unfolded pump housing 20 in their first form. Afterwards, the paddle assembly 100 reciprocates axially to perform the blood pumping operation. As can be seen, since the paddle assembly 100 of this application can switch between the first and second forms, when pushed into the patient's body, the paddle assembly 100 can be set to the second form with a smaller radial dimension, and the pump housing 20 can be compressed at the same time. This allows the blood pump 1 to maintain a smaller radial dimension when it is delivered in the body, thereby reducing the difficulty of pushing the blood pump 1 into the patient's body and increasing the range of vascular access, thereby expanding the scope of indications. In addition, when the paddle 110 is in the first form in its original state, the paddle assembly 100 can ensure a stable maximum radial dimension when it is propelling blood flow, so that the blood pump 1 can pump blood stably.

[0065] It should be noted that, Figure 6 The straight, wide arrow in the figure represents the radial shrinkage direction of the blade assembly 100 and the pump casing 20.

[0066] like Figure 3 As shown, in some embodiments of this application, the blade assembly 100 further includes at least one connecting pipe 120, which is disposed between two adjacent blades 110 or at the proximal end of the nearest blade 110. The connecting pipe 120 allows all blades 110 to be integrally engraved on the same nickel-titanium tube, ensuring the connection strength between adjacent blades 110. After all blades 110 are laser-engraved, they also need to undergo heat setting, electrochemical polishing, and other processes to form the blade assembly 100.

[0067] The number of connecting pipes 120 is set according to the number of blades 110. For example, the number of connecting pipes 120 may be the same as or one less than the number of blades 110.

[0068] The blade assembly 100 based on the above structure, such as Figure 3As shown, in some embodiments, the drive assembly 200 includes an inner tube 210 and an outer tube 220; the distal end of the outer tube 220 is connected to the nearest blade; the inner tube 210 has a connected proximal end 211 and a distal end 212, the proximal end 211 being movably fitted into the outer tube 220 and connected to the power mechanism 40, and the distal end 212 passing through each blade 110 and connected to the distal end of the farthest blade 110. The distal end of the outer tube 220 is used to fix the proximal end of the blade assembly 100. When the power mechanism 40 drives the inner tube 210 to reciprocate linearly, the distal end 212 of the inner tube 210 carries each blade 110 to reciprocate axially.

[0069] The inner tube 210 can be a corrugated tube, which not only gives it a certain degree of flexibility, making it easy to push through curved blood vessels, but also provides a certain degree of strength, enabling the impeller 110 to perform axial expansion and contraction. The corrugated tube can be laser-cut and can be made of biocompatible metals such as nickel-titanium alloy or 316L steel.

[0070] The inner tube 210 can be fixed to the far end of the farthest blade 110 by means of welding, hot melting or other methods. This application does not impose any specific restrictions on this.

[0071] The inner diameter of the outer tube 220 may be slightly larger than the outer diameter of the inner tube 210, and it may be made of medical polymer composite material. The distal end of the outer tube 220 may be connected to the nearest connecting tube 120 by welding, heat fusion or other methods, and this application does not impose specific restrictions.

[0072] like Figure 3 As shown, in some embodiments of this application, the paddle assembly 100 further includes a first imaging element (not shown in the figures) and a second imaging element 300. The first imaging element is located near the paddle assembly 100, and the second imaging element 300 is located far from the paddle assembly 100. With the assistance of imaging equipment such as X-ray fluoroscopy, the positions of the paddle assembly 100 relative to the blood flow inlet 20a and blood flow outlet 20b of the pump housing 20 can be determined by the first imaging element and the second imaging element 300. If the paddle assembly 100 is not in the preset position, for example, in the first configuration, the paddle assembly 100 is located between the blood flow inlet 20a and blood flow outlet 20b, the radial dimension of the pump housing 20 or the extension / retraction range of the paddle assembly 100 can be adjusted so that the paddle assembly 100 is not in the preset position, thereby ensuring the pumping efficiency of the blood pump 1.

[0073] The first developing element can be disposed at the far end of the outer tube 220 and close to the nearest blade 110, for example, on the nearest connecting tube 120. The first developing element can be made of platinum-iridium alloy or tantalum, and can be disposed on the nearest connecting tube 120 by laser welding or physical embedding (i.e., a groove is provided on the nearest connecting tube 120, and the first developing element is embedded in the groove on the nearest connecting tube 120). The number of the first developing elements can be one, two, three or more, and this application does not impose a specific limitation, as long as it can effectively and accurately position the near end of the blade assembly 100.

[0074] The second developing element 300 can be configured as a developing ring and located at the far end of the farthest blade 110. The material of the second developing element 300 can be a platinum-iridium alloy or a platinum-tungsten alloy, and it can be connected to the farthest blade 110 and the far end of the inner tube 210 by means of laser welding, hot melting, etc.

[0075] In some embodiments of this application, the blood pumping drive mechanism 10 further includes a protective coating (not shown in the drawings) disposed on the surface of the blade assembly 100. The protective coating may be disposed on the inner surface and / or outer surface of the blade assembly 100. For example, all surfaces of the first frame 1111, the second frame 1121, and the flow-blocking membrane 1112 of the blade 110 are provided with a protective coating.

[0076] The protective coating can be an antithrombotic coating or a hydrophilic coating. Such coatings can effectively prevent the adhesion of thrombi and reduce the probability of postoperative complications. As an example, both the inner and outer surfaces of the blade assembly 100 can be provided with an antithrombotic coating, or both can be provided with a hydrophilic coating, or one can be provided with an antithrombotic coating and the other with a hydrophilic coating.

[0077] On the other hand, such as Figure 1 As shown, one embodiment of this application also provides a blood pump 1, which includes a pump housing 20, a conduit 30, a power mechanism 40, and a blood pumping drive mechanism 10 as described in any of the above claims; the pump housing 20 has a blood inlet 20a and a blood outlet 20b, and the conduit 30 is disposed on the proximal side of the pump housing 20; the paddle assembly 100 of the blood pumping drive mechanism 10 is disposed in the pump housing 20, and the proximal end of the drive assembly 200 of the blood pumping drive mechanism 10 is connected to the power mechanism 40, and the power mechanism 40 can drive the paddle assembly 100 to reciprocate axially between the blood inlet 20a and the blood outlet 20b through the drive assembly 200.

[0078] The blood pump 1 can be implanted into the ventricle of a patient as an interventional catheter 30 pump, and can be used as a left ventricular interventional pump or a right ventricular interventional pump.

[0079] The blood pump 1 provided in this application embodiment has a paddle assembly 100 of the blood pumping drive mechanism 10 that can reciprocate axially under the drive of the drive assembly 200, so that it can switch between a first mode and a second mode, thereby performing blood pumping operation. The reciprocating axial extension and retraction of the paddle assembly 100 during blood pumping is equivalent to reciprocating linear motion, and the shear force generated by the reciprocating linear motion is much smaller than the shear force generated by the high-speed rotation of the impeller of the existing blood pump 1. In addition, the blood perfusion volume of the blood pump 1 can be increased by appropriately increasing the maximum radial dimension of the paddle assembly 100 in the first mode, the number of paddles 110, and the axial stroke of the paddle assembly 100 in the pump housing 20. In this way, the reciprocating axial extension and retraction frequency of the paddle assembly 100 can be increased or not increased by a small amount, avoiding the reciprocating axial extension and retraction frequency of the paddle assembly 100 being too large, so that the reciprocating axial extension and retraction frequency of the paddle assembly 100 is much lower than the high-speed rotation frequency of the impeller of the blood pump 1, and the shear force on blood cells can also be effectively reduced. In summary, the blood pump 1 provided in this application can effectively reduce the shear force on blood cells, thereby greatly eliminating the risk of hemolysis. At the same time, the clinical application time and stability of the product are greatly improved, and it can achieve the effect of low-frequency operation and high blood perfusion.

[0080] In some embodiments of this application, a protective layer may also be provided on the surface of the pump housing 20. The protective layer may be on the inner and / or outer surface of the pump housing 20. The protective layer may be an antithrombotic coating or a hydrophilic coating, which can effectively prevent the adhesion of thrombi and reduce the probability of postoperative complications.

[0081] In some embodiments of this application, the power mechanism 40 may include one of a reciprocating linear motor, a cylinder, a hydraulic cylinder, and a mechanism consisting of a rotary motor and a crank-connecting rod. The power mechanism 40 is connected to the proximal end of the inner tube 210 of the drive assembly 200.

[0082] In some embodiments of this application, the power mechanism 40 is located proximal to the catheter 30, and the proximal end of the inner tube 210 passes through the catheter 30 and is connected to the power mechanism 40. Placing the power mechanism 40 outside the patient's body can prevent the power mechanism 40 from generating abrasive particles that may detach inside the patient's body, and can also prevent thrombosis problems caused by the power mechanism 40 generating heat during operation. Of course, in other embodiments, the power mechanism 40 may also be located inside the patient's body, specifically, between the distal end of the catheter 30 and the proximal end of the outer tube 220.

[0083] In some embodiments of this application, such as Figure 1 As shown, the blood pump 1 also includes a flexible end 50, which is located at the distal end of the pump housing 20. The flexible end 50 can abut against the inner wall of the tissue to position the distal end of the blood pump 1, and can also protect the blood vessel when the blood pump 1 is pushed. The flexible end 50 can be a tube structure such as a pig tail shape, a ball shape, an arrow shape, or a rhombus shape.

[0084] The flexible end 50 can be made of medical silicone or polyurethane mixed with radiopaque material, which gives the flexible end 50 a certain degree of softness, radiopaque function, and can also locate the position of the blood pump 1.

[0085] To ensure that the blade assembly 100 can extend and retract in a specific direction under the drive of the inner tube 210, in some embodiments of this application, such as Figure 1 As shown, the blood pump 1 also includes a directional shaft 60, the proximal end of which extends out of the inner tube 210, and the distal end of which passes through the impeller assembly 100 and is connected to the flexible end 50 at the distal end of the pump housing 20. The impeller assembly 100 can reciprocate axially along the directional shaft 60, enabling the impeller assembly 100 to pump blood in a directional manner.

[0086] The directional shaft 60 may be a flexible metal shaft. The distal end of the directional shaft 60 may protrude from the flexible end 50 and may be connected to the flexible end 50 by means of welding, hot melting, etc. This application does not impose specific restrictions on this.

[0087] In summary, the blood pump 1 provided in this application has the following effects:

[0088] 1. Its unique reciprocating blood pump blade 110 design is different from the existing axial flow spiral impeller structure. During its operation, it can greatly eliminate shear force, which can effectively reduce the risk of hemolysis, making the surgery safer and the service life longer.

[0089] 2. The overall structure and manufacturing process of the impeller 110 and pump casing 20 have relatively stable and low costs and high feasibility; they are simple and easy to operate, effectively reducing costs while improving safety and reliability.

[0090] 2. The size of both the impeller 110 and the pump casing 20 is adjustable, allowing for a smaller overall size design, reducing the occurrence of complications, and broadening the range of indications;

[0091] 4. The built-in design of multiple paddle blades 110 and the adjustable reciprocating motion frequency of the external power mechanism 40 can provide better hemodynamics, that is, higher blood flow.

[0092] 5. The opening and closing action of the built-in multiple blades 110 has minimal shear force on the blood and eliminates the continuous noise of the high-speed operation of the axial flow pump motor, thus having less impact on the patient.

[0093] 6. The built-in impeller 110 and pump housing 20 are coated with a protective coating, which can effectively prevent the adhesion of thrombi and reduce the occurrence of related complications;

[0094] On the other hand, such as Figure 4As shown, one embodiment of this application provides a ventricular assist system, which includes a handle mechanism 2 and a blood pump 1 as described above, with the proximal end of a catheter 30 connected to the handle mechanism 2. It should be noted that... Figure 4 The image only shows the mounting position of the handle mechanism 2, and does not show the structure of the handle mechanism 2.

[0095] The ventricular assist system provided in this application embodiment has a paddle assembly 100 of the blood pumping drive mechanism 10 that can reciprocate axially under the drive of the drive assembly 200, so that it can switch between a first mode and a second mode, thereby enabling blood pumping operation. The reciprocating axial extension and retraction of the paddle assembly 100 during blood pumping is equivalent to reciprocating linear motion, and the shear force generated by the reciprocating linear motion is much smaller than the shear force generated by the high-speed rotation of the impeller of the existing blood pump 1. In addition, the blood perfusion volume of the blood pump 1 can be increased by appropriately increasing the maximum radial dimension of the paddle assembly 100 in the first mode, the number of paddles 110, and the axial stroke of the paddle assembly 100 in the pump housing 20. In this way, the reciprocating axial extension and retraction frequency of the paddle assembly 100 can be increased or not increased by a small amount, avoiding the reciprocating axial extension and retraction frequency of the paddle assembly 100 being too high. This ensures that the reciprocating axial extension and retraction frequency of the paddle assembly 100 is much lower than the high-speed rotation frequency of the impeller of the blood pump 1, and can also effectively reduce the shear force on blood cells. In summary, the pump drive mechanism 10 of the ventricular assist system provided in this application can effectively reduce the shear force on blood cells, thereby greatly eliminating the risk of hemolysis. At the same time, the clinical application time and stability of the product are greatly improved, and it can achieve the effect of low-frequency operation and high blood perfusion.

[0096] In some embodiments of this application, the handle mechanism 2 may be provided with a movable first operating button (not shown in the figures). The pump housing 20 can be expanded or contracted by controlling the first operating button to push the conduit 30 forward or retract it backward. The first operating button may be a knob or a toggle button.

[0097] The handle mechanism 2 may also be provided with a movable second operating button (not shown in the attached drawings). The power mechanism 40 of the blood pump 1 may be located on the handle mechanism 2 and connected to the second operating button. The power mechanism 40 can be moved forward or backward by controlling the second operating button, thereby adjusting the initial position of the paddle assembly 100 in the pump housing 20. The second operating button may be a knob or a toggle switch.

[0098] 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.

[0099] 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 blood pumping drive mechanism for a blood pump, characterized in that, include: A blade assembly having a first form and a second form, wherein the maximum radial dimension of the blade assembly in the first form is greater than the maximum radial dimension in the second form; the blade assembly includes a plurality of blades connected sequentially from near to far, wherein in the first form each blade is deployed, and in the second form each blade is retracted; A drive assembly is capable of driving the blade assembly to reciprocate axially, thereby allowing the blade assembly to alternate between a first mode and a second mode, and thus enabling the blade assembly to perform a blood pumping operation. The drive assembly includes an inner tube and an outer tube. The distal end of the outer tube is connected to the nearest blade. The inner tube has a connected proximal end and a distal end, the proximal end being movably fitted into the outer tube, and the distal end passing through each blade and connected to the farthest blade.

2. The blood pumping drive mechanism according to claim 1, characterized in that, The maximum radial dimension of the plurality of blades in the first configuration decreases sequentially along the pumping direction.

3. The blood pumping drive mechanism according to claim 1, characterized in that, The blade includes a closed section and a hollow section connected together. The closed section and the hollow section are arranged sequentially along the pumping direction, and the radial dimension is largest at the connection between the closed section and the hollow section.

4. The blood pumping drive mechanism according to claim 3, characterized in that, The radial dimension of the closed segment gradually increases along the pumping direction in both the first and second forms, while the radial dimension of the hollow segment gradually decreases along the pumping direction in both the first and second forms.

5. The blood pumping drive mechanism according to claim 3, characterized in that, The closed section includes a first skeleton and a flow-blocking membrane, the flow-blocking membrane being applied to the first skeleton, and the first skeleton being connected to the perforated section; and / or The hollow section includes a second skeleton, which is connected to the closed section.

6. The blood pumping drive mechanism according to claim 5, characterized in that, The first frame is made of shape memory material, and when the first frame is in its initial state, the blades are in the first shape; and / or, The second frame is made of shape memory material, and when the second frame is in its initial state, the blades are in the first shape.

7. The blood pumping drive mechanism according to claim 1, characterized in that, The blade assembly further includes at least one connecting pipe disposed between two adjacent blades or at the proximal end of the blade on the nearest side.

8. The blood pumping drive mechanism according to claim 7, characterized in that, The inner tube is a thiocyanate tube.

9. The blood pumping drive mechanism according to any one of claims 1 to 8, characterized in that, The blood pumping drive mechanism also has at least one of the following features: The blood pumping drive mechanism further includes a first imaging element, which is disposed near the blade assembly. The blood pumping drive mechanism further includes a second imaging element, which is located on the distal side of the blade assembly. The blood pumping drive mechanism also includes a protective coating, which is disposed on the surface of the blade assembly.

10. A blood pump, characterized in that, Includes a pump housing, a conduit, a power mechanism, and a blood pumping drive mechanism as described in any one of claims 1 to 9; The pump housing has a blood inlet and a blood outlet. The conduit is located on the proximal side of the pump housing. The paddle assembly of the blood pumping drive mechanism is located in the pump housing. The proximal end of the drive assembly of the blood pumping drive mechanism is connected to the power mechanism. The power mechanism can drive the paddle assembly to reciprocate axially between the blood inlet and the blood outlet through the drive assembly.

11. A ventricular assist system, characterized in that, It includes a handle mechanism and a blood pump as described in claim 10, wherein the proximal end of the catheter of the blood pump is connected to the handle mechanism.

Images