Pumping blood driving mechanism of blood pump, blood pump and ventricular assist system

Abstract

The invention relates to a pump blood 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 blade assembly has a first form and a second form, and the maximum radial size of the blade assembly in the first form is larger than the maximum radial size of the blade assembly in the second form; the driving assembly can drive the paddle assembly to axially stretch out and draw back in a reciprocating mode so that the paddle assembly can be switched between the first form and the second form in turn, and then the paddle assembly can conduct blood pumping operation. The blood pumping driving mechanism can effectively reduce the shearing force on blood cells, so that the hemolysis risk is greatly eliminated, meanwhile, 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 achieved.

Description

Technical Field

[0001] The present application relates to the technical field of medical devices, and in particular to a blood pumping drive mechanism of a blood pump, a blood pump and a ventricular assist system. Background Art

[0002] Interventional catheter pumps, also known as blood pumps, are mostly used to be implanted from blood vessels into the patient's ventricles to assist the patient's heart in pumping blood from the ventricles to the arteries, thereby providing support for the patient's blood circulation. Among them, the traditional blood pump includes a pump housing, an impeller, a motor and a catheter; the motor is arranged between the pump housing and the catheter, and the impeller, as a blood pumping drive mechanism, can rotate in the pump housing under the drive of the motor, and can flow blood into the pump housing through the blood flow inlet of the pump housing and out of the blood flow outlet of the pump housing.

[0003] However, the shear force generated by the high-speed rotation of the impeller will destroy the red blood cells, thereby producing potential hemolytic side effects. The longer the operation time, the greater the side effects and the higher the incidence of complications. Summary of the invention

[0004] Based on this, it is necessary to provide a blood pumping drive mechanism, a blood pump and a ventricular assist system for the above-mentioned technical problems.

[0005] A blood pump driving mechanism of a blood pump, comprising:

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

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

[0008] In one embodiment, the blade assembly includes a plurality of blades connected in sequence from near to far, and in the first form, each of the blades is unfolded, and in the second form, each of the blades is folded.

[0009] In one embodiment, the maximum radial dimensions of the plurality of blades in the first form decrease sequentially along the blood pumping direction.

[0010] In one embodiment, the paddle comprises a connected closed segment and a hollow segment, the closed segment and the hollow segment are arranged in sequence along the blood pumping direction, and the radial dimension of the connection between the closed segment and the hollow segment is the largest.

[0011] In one embodiment, the radial dimensions of the closed segment in the first form and the second form gradually increase along the blood pumping direction, and the radial dimensions of the hollow segment in the first form and the second form gradually decrease along the blood pumping direction.

[0012] In one embodiment, the closed section includes a first frame and a flow-blocking film, the flow-blocking film is covered on the first frame, and the first frame is connected to the hollow section; and / or,

[0013] The hollow section includes a second frame 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 an initial state, the blade is in the first shape; and / or,

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

[0016] In one embodiment, the blade assembly further includes at least one connecting tube, and the connecting tube is disposed between two adjacent blades or at the proximal end of the blade closest to the blade.

[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 paddle blade; the inner tube has a proximal end and a distal end connected to each other, the proximal end is movably sleeved in the outer tube, and the distal end is passed through each of the paddle blades and connected to the farthest paddle blade.

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

[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 developing member, which is disposed on the proximal side of the paddle assembly;

[0021] The blood pumping drive mechanism further includes a second developing member, which is disposed at the distal side of the paddle assembly;

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

[0023] A blood pump, comprising a pump housing, a catheter, a power mechanism and a blood pumping drive mechanism as described in any one of the above items;

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

[0025] A ventricular assist system comprises 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 pump, the blade assembly of the blood pumping drive mechanism can be reciprocated axially extended and retracted under the drive of the drive assembly, so that it can switch between the first form and the second form alternately, and then can perform blood pumping operation, wherein the reciprocating axial extension and reciprocating 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 of the existing blood pump; 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 form, the number of blades, the axial stroke of the blade assembly in the pump housing, etc., so that the reciprocating axial extension and retraction frequency of the blade assembly can be slightly increased or not increased, avoiding the reciprocating axial extension and retraction frequency of the blade assembly being too large, so that the reciprocating axial extension and reciprocating frequency of the blade assembly is much lower than the high-speed rotation frequency of the impeller of the blood pump, and the shear force on blood cells can also be effectively reduced. In summary, the blood pump drive mechanism, blood pump and ventricular assist system provided in this application can effectively reduce the shear force on blood cells and thus greatly eliminate 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. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A schematic diagram of the structure of a blood pump provided in one embodiment of the present application.

[0028] Figure 2 for Figure 1 A schematic diagram of the implantation of a blood pump in a patient is provided.

[0029] Figure 3 for Figure 1 A schematic structural diagram of a blood pump driving mechanism of a blood pump is provided when the blade assembly is in a first form.

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

[0031] Figure 5 for Figure 3A schematic structural diagram of the first and second skeletons of the blood pumping drive mechanism is provided when the blade assembly is in a first form.

[0032] Figure 6 for Figure 1 A schematic diagram of the structure of the blood pump when it is pushed in the body is provided.

[0033] The reference numerals in the accompanying drawings are described as follows:

[0034] 1. Blood pump; 10. Blood pump driving mechanism; 100. Paddle assembly; 110. Paddle; 111. Closed section; 1111. First skeleton; 1111a. First support rod; 1112. Flow blocking membrane; 112. Hollow section; 1121. Second skeleton; 1121a. Second support rod; 120. Connecting tube; 200. Driving assembly; 210. Inner tube; 211. Proximal end; 212. Distal end; 220. Outer tube; 300. Second developing part; 20. Pump housing; 20a. Blood inlet; 20b. Blood outlet; 30. Catheter; 40. Power mechanism; 50. Flexible terminal; 60. Directional axis; 2. Handle; M. Left ventricle; N. Aorta. DETAILED DESCRIPTION

[0035] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0036] In the description of the present application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0037] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0038] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0039] In the present application, unless otherwise clearly specified and limited, if there is a description that a first feature is "above" or "below" a second feature, etc., or similar descriptions appear, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0040] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. If present, 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 implementation method.

[0041] It should be noted that the terms “distal end” and “proximal end” throughout the text are only used to indicate relative positional relationships. The “distal end” of a component refers to the end of the component that enters the patient's body first compared to the other end during normal operation and / or the end that is farther away from the operator, while the “proximal end” refers to the end that enters the patient's body later than the other end and / or the end that is closer to the operator.

[0042] Interventional catheter pumps, also known as blood pumps, are mostly used to be implanted from blood vessels into the patient's ventricles to assist the patient's heart in pumping blood from the ventricles to the arteries, thereby providing support for the patient's blood circulation. Among them, the traditional blood pump includes a pump housing, an impeller, a motor and a catheter; the motor is arranged between the pump housing and the catheter, and the impeller, as a blood pumping drive mechanism, can rotate in the pump housing under the drive of the motor, and can flow blood into the pump housing through the blood flow inlet of the pump housing and out of the blood flow outlet of the pump housing.

[0043] In order to generate sufficient centrifugal force, maintain the stability of blood flow and ensure blood perfusion efficiency, the impeller speed of traditional blood pumps is generally very high, especially the impeller of axial flow blood pumps, which can be as high as 7000-15000 revolutions per minute (rpm). However, when the impeller rotates at high speed, the shear force generated is greater, and the degree of damage to red blood cells is greater, thus generating potential hemolytic side effects. The longer the operation time, the greater the side effects and the higher the incidence of complications.

[0044] In this regard, an embodiment of the present application provides a blood pumping drive mechanism, which can be used as a blood pumping drive mechanism of a blood pump, mainly providing power for the flow of blood, and can promote the flow of blood, thereby achieving a blood pumping operation. Among them, the blood pump can be implanted into the patient's ventricle as an interventional catheter pump, such as Figure 1 As shown, the blood pump 1 includes a pump housing 20, a catheter 30, a power mechanism 40 and a blood pumping drive mechanism 10; the pump housing 20 is arranged on the distal side of the catheter 30 and has a blood flow inlet 20a and a blood flow outlet 20b, and the pump housing 20 can be contracted or expanded to adjust its own radial size; 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 flow inlet 20a of the pump housing 20 and flows out from the blood flow outlet 20b of the pump housing 20. Figure 1 The arrow X+ in the figure indicates the direction from the proximal end to the distal end; the arrow X- indicates the direction from the distal end to the proximal end. Figure 1 Only the installation position of the power mechanism 40 is shown, and the specific structure of the power mechanism 40 is not given; in addition, Figure 1 The straight dotted lines on the proximal and distal sides of the middle pump housing 20 are only used to define the blood flow outlet 20b and the blood flow outlet 20a of the pump housing 20 and have no special meaning.

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

[0046] Specifically, 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 in the pump housing 20 and has a first form and a second form. The maximum radial dimension of the blade assembly 100 in the first form is greater than the maximum radial dimension in the second form. The proximal end of the drive assembly 200 is connected to the power mechanism 40, and can rely on the power of the power mechanism 40 to drive the blade assembly 100 to reciprocate axially and extend and retract, so that the blade assembly 100 switches alternately between the first form and the second form, thereby enabling the blade assembly 100 to perform a blood pumping operation. Figure 4 As shown, when the driving assembly 200 drives the blade assembly 100 to compress from the blood flow inlet 20a of the pump housing 20 toward the blood flow outlet 20b, the blade assembly 100 can switch from the second form to the first form, and the radial size of the blade assembly 100 becomes larger, so that the blade assembly 100 can bring the blood at the blood flow inlet 20a to the blood flow outlet 20b during compression, and then pump it into the patient's blood vessel; and when the driving assembly 200 drives the blade assembly 100 to extend from the blood flow outlet 20b of the pump housing 20 toward the blood flow inlet 20a, the blade assembly 100 can switch from the first form to the second form, and the radial size of the blade assembly 100 becomes smaller, so that the blade assembly 100 will not reversely bring blood from the blood flow outlet 20b to the blood flow inlet 20a. The blade assembly 100 repeats the above steps, that is, through reciprocating axial expansion and contraction and synchronous switching of its own form, blood perfusion can be achieved, which is similar to the irrigation principle of the ancient keel waterwheel. Figure 4 The flow direction of blood when the paddle assembly 100 switches between the first state and the second state is shown. Figure 4 The curved dotted arrows in the figure represent the flow direction of blood, while the straight wide arrows represent the extension and retraction direction of the paddle assembly 100.

[0047] like Figure 3 and Figure 4As shown, the blade assembly 100 includes a plurality of blades 110 connected in sequence from near to far, and in the first form, each blade 110 is unfolded, and in the second form, each blade 110 is folded. It should be noted that when the blade assembly 100 switches between the first form and the second form, each blade 110 opens and closes successively or synchronously. In the first form, 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 form; in the second form, 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 form.

[0048] Taking into account the processing cost and the axial dimension of the pump housing 20 of the blood pump 1 , the number of the 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 dimensions of the multiple blades 110 in the first form decrease successively along the blood pumping direction. The radial dimensions of the multiple blades 110 are set in this way, which can guide the flow of blood in the pump housing 20, and can also prevent the blood from forming vortices in the pump housing 20, thereby improving the blood pumping efficiency of the blood pump 1. It should be noted that the "blood pumping direction" in the full text refers to the flow direction of blood from the blood flow inlet 20a to the blood flow outlet 20b of the pump housing 20. Among them, when the blood pump 1 is a left heart interventional pump, the maximum radial dimensions of the multiple blades 110 in the first form gradually decrease from the distal end to the proximal end of the pump housing 20; when the blood pump 1 is a right heart interventional pump, the maximum radial dimensions of the multiple blades 110 in the first form gradually decrease from the proximal end 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 blade assembly 100 in the first form, the number of blades 110, the axial stroke of the blade assembly 100 in the pump housing 20, and the reciprocating axial telescopic frequency of the blade assembly 100. Specifically, the greater the blood perfusion volume of the blood pump 1, the greater the maximum radial dimension of the blade assembly 100 in the first form, the number of blades 110, the axial stroke of the blade assembly 100 in the pump housing 20, and the reciprocating axial telescopic frequency of the blade 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 maximum radial dimension of the blade assembly 100 in the first form, the number of blades 110, the axial stroke of the blade assembly 100 in the pump housing 20, and the reciprocating axial telescopic frequency of the blade assembly 100. In order to prevent the blade assembly 100 from having excessive shear force due to excessive reciprocating axial expansion and contraction frequency, when the blood perfusion volume of the blood pump 1 needs to be increased, the maximum radial dimension of the blade assembly 100 in the first form, the number of blades 110, and the axial stroke of the blade assembly 100 in the pump housing 20 can be appropriately increased accordingly. In this way, the reciprocating axial expansion and contraction frequency of the blade assembly 100 can be slightly increased or not increased, thereby preventing the reciprocating axial expansion and contraction frequency of the blade assembly 100 from being too large.

[0051] It can be seen that in the blood pumping drive mechanism 10 provided in the embodiment of the present application, the blade assembly 100 can be reciprocated axially extended and retracted under the drive of the drive assembly 200, so that it can switch between the first form and the second form alternately, and then can perform blood pumping operation, wherein the reciprocating axial extension and reciprocating of the blade 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 blade assembly 100 in the first form, the number of blades 110, the axial stroke of the blade assembly 100 in the pump housing 20, etc., so that the reciprocating axial extension and retraction frequency of the blade assembly 100 can be slightly increased or not increased, and the reciprocating axial extension and retraction frequency of the blade assembly 100 is avoided to be too large, so that the reciprocating axial extension and reciprocating frequency of the blade 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 drive mechanism 10 provided in the present application can effectively reduce the shear force on blood cells and thus greatly eliminate 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.

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

[0053] like Figure 3 As shown, the radial dimensions of the closed section 111 in the first form and the second form gradually increase along the direction of blood pumping, and the radial dimensions of the hollow section 112 in the first form and the second form gradually decrease along the direction of blood pumping. The closed section 111 and the hollow section 112 of this structure are similar to two umbrella structures arranged opposite to each other, which facilitates the deployment and folding of the blades 110. Among them, when the blood pump 1 is a left heart interventional pump, the radial dimensions of the closed section 111 in the first form and the second form gradually decrease from near to far, and the radial dimensions of the hollow section 112 in the first form and the second form gradually increase from near to far; when the blood pump 1 is a right heart interventional pump, the radial dimensions of the closed section 111 in the first form and the second form gradually increase from near to far, and the radial dimensions of the hollow section 112 in the first form and the second form gradually decrease from near to far.

[0054] like Figure 3 As shown, the closed section 111 includes a first frame 1111 and a flow-blocking film 1112. The flow-blocking film 1112 is covered on the first frame 1111, and the first frame 1111 is connected to the hollow section 112. The closed section 111 of this structure can be expanded or collapsed by deformation of the first frame 1111, and the flow-blocking film 1112 is used to drive the blood to flow in the pump housing 20 in a directional manner. It can be seen that the closed section 111 of this structure is convenient for driving the flow of blood and is convenient for expansion or collapse.

[0055] like Figure 5 As shown, the first skeleton 1111 includes a plurality of first support rods 1111a, which are sequentially arranged along the circumference of the blade assembly 100, and one end of the first support rod 1111a is connected to the hollow section 112 of the same blade 110 and the hollow section 112 of the adjacent blade 110. The first skeleton 1111 of this structure is simple in structure, easy to produce and process, and also easy to unfold or fold the closed section 111. Of course, in some other embodiments, the first skeleton 1111 can be set as a grid skeleton structure.

[0056] The number of the first support rods 1111a can be 8 to 16, for example, 8, 9, 10, 11, 12, 13, 14, 15 or 16, without specific limitation, as long as the strength of the closed section 111 and the smooth unfolding or folding are guaranteed. The diameter of the first support rod 1111a can be 0.1 mm to 0.25 mm, for example, 0.1 mm, 0.15 mm, 0.2 mm and 0.25 mm, etc., and the present application does not make specific limitation on this, as long as the strength of the closed section 111 and the smooth unfolding or folding are guaranteed.

[0057] The first skeleton 1111 of the structure can be formed by laser engraving, for example, laser engraving is performed on the nickel-titanium alloy tube during processing. Alternatively, the first skeleton 1111 can be formed by weaving, for example, nickel-titanium wires are weaved during processing. After the first skeleton 1111 is laser engraved or woven, it is also necessary to perform heat setting, electrochemical polishing and other processes.

[0058] The flow-blocking membrane 1112 can be made of biocompatible materials such as e-PTFE (expended polytetrafluoroethylene), TPU (Thermoplastic Polyurethanes), and nylon. The flow-blocking membrane 1112 of such materials has a certain elasticity and can be folded or unfolded synchronously with the first frame 1111, and will not fall off the first frame 1111 due to excessive changes in the radial dimensions of the first frame 1111, thereby ensuring normal blood pumping of the blood pump 1.

[0059] The baffle film 1112 can be sewn to the first frame 1111. Specifically, the baffle film 1112 can be sewn to the first frame 1111 using sutures made of materials such as PET (Polyethyleneterephthalate), polytetrafluoroethylene or PP (Polypropylene). Of course, the baffle film 1112 can also be set on the first frame 1111 by hot pressing.

[0060] The flow-blocking membrane 1112 can be disposed on the inner circumference of the first skeleton 1111, or on the outer circumference of the first skeleton 1111, or on the inner and outer circumferences of the first skeleton 1111. The present application does not impose any specific restrictions on this, as long as it can effectively block the blood flow.

[0061] Continue to see Figure 5, the hollow section 112 may also include a second skeleton 1121, and the second skeleton 1121 is connected to the first skeleton 1111 of the closed section 111. Among them, the second skeleton 1121 includes a plurality of second support rods 1121a, and the plurality of second support rods 1121a are sequentially arranged along the circumference of the blade assembly 100, and one end of the second support rod 1121a is connected to the closed section 111 of the same blade 110 and the closed section 111 of the adjacent blade 110. The second skeleton 1121 of this structure has a simple structure, is easy to produce and process, and is also easy to unfold or fold the closed section 111. Of course, in some other embodiments, the second skeleton 1121 can be set as a grid skeleton structure.

[0062] The number of the second support rods 1121a can be 8 to 16, for example, 8, 9, 10, 11, 12, 13, 14, 15 or 16, and the present application does not impose any specific restrictions on this, as long as the strength of the hollow section 112 and the smooth expansion or folding can be guaranteed. The diameter of the second support rod 1121a can be 0.1 mm to 0.25 mm, for example, 0.1 mm, 0.15 mm, 0.2 mm and 0.25 mm, etc., and there is no specific restriction on this, as long as the strength of the hollow section 112 and the smooth expansion or folding can be guaranteed.

[0063] The second frame 1121 of the structure can be formed by laser engraving, for example, laser engraving is performed on the nickel-titanium alloy tube during processing. Alternatively, the second frame 1121 can be formed by weaving, for example, nickel-titanium wires are weaved during processing. After the second frame 1121 is laser engraved or woven, it is also necessary to perform heat setting, electrochemical polishing and other processes.

[0064] The first frame 1111 is a shape memory material. When the first frame 1111 is in the initial state, the blade 110 is in the first shape. The second frame 1121 is a shape memory material. When the second frame 1121 is in the initial state, the blade 110 is in the first shape. Figure 6As shown, when the blood pump 1 is inserted into the patient's body, the paddle assembly 100 can be placed in the pump housing 20 first, and the pump housing 20 and the paddle assembly 100 are stretched at the same time (the paddle assembly 100 is in the second form at this time), so that the pump housing 20 can carry the paddle assembly 100 into the sheath; when pushed in 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 withdrawn, the pump housing 20 is unfolded, and at this time the first frame 1111 and the second frame 1121 of the paddle 110 are also reset and unfolded, and placed in the unfolded pump housing 20 in the first form. Afterwards, the paddle assembly 100 reciprocates and axially expands and contracts to perform blood pumping operation. It can be seen that the paddle assembly 100 of the present application can switch between the first form and the second form. When pushing in 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, so that the blood pump 1 can maintain a smaller radial dimension when being delivered in the body, thereby reducing the difficulty of pushing the blood pump 1 in the patient's body, and also increasing the range of blood vessels that can be intervened, thereby improving the scope of indications; in addition, the paddle 110 is in the first form in the original state, so that the paddle assembly 100 can ensure a stable maximum radial dimension when promoting 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 represents the radial dimension shrinking direction of the impeller assembly 100 and the pump housing 20 .

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

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

[0068] Based on the above structure of the blade assembly 100, 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 most proximal blade; the inner tube 210 has a proximal portion 211 and a distal portion 212 connected, the proximal portion 211 is movably sleeved in the outer tube 220 and connected to the power mechanism 40, and the distal portion 212 is penetrated in each blade 110 and connected to the distal end of the most distal blade 110. The distal end of the outer tube 220 is used to fix the proximal end of the blade assembly 100, and when the power mechanism 40 drives the inner tube 210 to reciprocate linearly, the distal portion 212 of the inner tube 210 drives each blade 110 to reciprocate axially.

[0069] The inner tube 210 can be a hypotube, which not only makes the inner tube 210 flexible to facilitate pushing in curved blood vessels, but also has a certain strength to push the blades 110 to perform complex axial expansion and contraction. The bellows can be cut by laser, and the material can be a biocompatible metal material such as nickel-titanium alloy, 316L steel, etc.

[0070] The inner tube 210 may be fixed to the distal end of the farthest blade 110 by welding, hot melting, etc., and this application does not impose any specific limitation 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 may be made of a medical polymer composite material. The distal end of the outer tube 220 may be connected to the proximal connecting tube 120 by welding, hot melting, etc., and this application does not make specific restrictions.

[0072] like Figure 3 As shown, in some embodiments of the present application, the paddle assembly 100 further includes a first developing member (not shown in the drawings) and a second developing member 300, the first developing member is disposed on the proximal side of the paddle assembly 100, and the second developing member 300 is disposed on the distal side of the paddle assembly 100. With the assistance of imaging equipment such as X-ray fluoroscopy, the position of the paddle assembly 100 relative to the blood flow inlet 20a and the blood flow outlet 20b of the pump housing 20 can be determined by the first developing member and the second developing member 300. If the paddle assembly 100 is not in the preset position, for example, in the first form, the paddle assembly 100 is located between the blood flow inlet 20a and the blood flow outlet 20b, the radial dimension of the pump housing 20 or the telescopic range of the paddle assembly 100 can be adjusted so that the paddle assembly 100 is not in the preset position, thereby ensuring the blood pumping efficiency of the blood pump 1.

[0073] The first developing member may be disposed at the distal end of the outer tube 220 and close to the most proximal blade 110, for example, on the most proximal connecting tube 120. The first developing member may be made of a platinum-iridium alloy or tantalum, and may be disposed on the most proximal connecting tube 120 by laser welding or physical inlaying (i.e., a groove is provided on the most proximal connecting tube 120, and the first developing member is inlaid in the groove on the most proximal connecting tube 120). The number of the first developing members may be 1, 2, 3 or more, and the present application does not impose any specific limitation, as long as the proximal end of the blade assembly 100 can be effectively and accurately positioned.

[0074] The second developing member 300 may be a developing ring and disposed at the distal end of the most distal blade 110. The second developing member 300 may be made of a platinum-iridium alloy or a platinum-tungsten alloy and may be connected to the most distal blade 110 and the distal end of the inner tube 210 by laser welding, hot melting or the like.

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

[0076] The protective coating may be an anti-thrombotic coating or a hydrophilic coating, which can effectively prevent the attachment of thrombi and reduce the probability of postoperative complications. As an example, the inner surface and the outer surface of the blade assembly 100 may both be provided with an anti-thrombotic coating, or both be provided with a hydrophilic coating, or one may be provided with an anti-thrombotic coating and the other may be provided with a hydrophilic coating.

[0077] On the other hand, Figure 1 As shown, an embodiment of the present application further provides a blood pump 1, which includes a pump housing 20, a catheter 30, a power mechanism 40 and a blood pumping drive mechanism 10 as described in any one of the above items; the pump housing 20 has a blood flow inlet 20a and a blood flow outlet 20b, and the catheter 30 is arranged on the proximal side of the pump housing 20; the paddle assembly 100 of the blood pumping drive mechanism 10 is arranged in the pump housing 20, and the proximal end of the driving 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 flow inlet 20a and the blood flow outlet 20b through the driving assembly 200.

[0078] The blood pump 1 can be implanted into the patient's ventricle as an interventional catheter 30 pump, and can be either a left heart interventional pump or a right heart interventional pump.

[0079] In the blood pump 1 provided in the embodiment of the present application, the blade assembly 100 of the blood pumping drive mechanism 10 can reciprocate and axially extend and retract under the drive of the drive assembly 200, so as to switch itself alternately between the first form and the second form, thereby being able to perform a blood pumping operation, wherein the reciprocating axial extension and reciprocating of the blade 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 blade assembly 100 in the first form, the number of blades 110, the axial stroke of the blade assembly 100 in the pump housing 20, etc., so that the reciprocating axial extension and retraction frequency of the blade assembly 100 can be slightly increased or not increased, and the reciprocating axial extension and retraction frequency of the blade assembly 100 can be avoided to be too large, so that the reciprocating axial extension and reciprocating frequency of the blade 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 the present application can effectively reduce the shear force on blood cells and thus greatly eliminate 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.

[0080] In some embodiments of the present 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 anti-thrombotic coating or a hydrophilic coating, which can effectively prevent the attachment of thrombi and also reduce the probability of postoperative complications.

[0081] In some embodiments of the present application, the power mechanism 40 may include one of a reciprocating linear motor, a cylinder, a hydraulic cylinder, and a mechanism composed 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 driving assembly 200 .

[0082] In some embodiments of the present application, the power mechanism 40 is disposed on the proximal side of 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 wear particles that fall off in the patient's body, and can also prevent the power mechanism 40 from generating heat during operation and causing thrombosis. Of course, in some other embodiments, the power mechanism 40 can also be disposed inside the patient's body, specifically, the power mechanism 40 is disposed between the distal end of the catheter 30 and the proximal end of the outer tube 220.

[0083] In some embodiments of the present application, Figure 1 As shown, the blood pump 1 further includes a flexible end 50, which is disposed 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 the flexible end 50 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 pigtail shape, a spherical shape, an arrow shape, or a prism shape.

[0084] The flexible end 50 may be made of materials such as medical silicone or polyurethane mixed with a developing material, which makes the flexible end 50 have a certain degree of softness and a developing function, and can also locate the position of the blood pump 1.

[0085] In order to ensure that the blade assembly 100 can be directional and retractable under the drive of the inner tube 210, in some embodiments of the present application, such as Figure 1 As shown, the blood pump 1 further 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 paddle assembly 100 and is connected to the flexible end 50 at the distal end of the pump housing 20. The paddle assembly 100 can reciprocate axially along the directional shaft 60, so that the paddle assembly 100 can pump blood in a directional manner.

[0086] The directional shaft 60 may be a metal soft shaft. The distal end of the directional shaft 60 may be exposed from the flexible end head 50 and may be connected to the flexible end head 50 by welding, hot melting, etc., and the present application does not impose any 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 pumping blade 110 design is different from the existing axial flow spiral impeller structure. It can greatly eliminate shear force during operation, which can effectively reduce the risk of hemolysis, making the operation safer and longer in service life;

[0089] 2. The overall structure and processing cost of the impeller 110 and the pump housing 20 are relatively stable and low, with a high feasibility; they are simple and easy to operate, which can effectively reduce costs while improving safety and reliability;

[0090] 2. The sizes of the impeller 110 and the pump housing 20 are adjustable, and the overall size can be designed to be smaller, reducing the occurrence of complications and expanding the scope of indications;

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

[0092] 5. The opening and closing action of the built-in multiple paddles 110 exerts very little shear force on the blood, and there is no continuous noise caused by the high-speed operation of the axial flow pump motor, which has less impact on the patient;

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

[0094] On the other hand, Figure 4As shown, an embodiment of the present application provides a ventricular assist system, which includes a handle mechanism 2 and the blood pump 1 as described above, and the proximal end of the catheter 30 is connected to the handle mechanism 2. It should be noted that, Figure 4 Only the installation position of the handle mechanism 2 is shown, and the structure of the handle mechanism 2 is not shown.

[0095] In the ventricular assist system provided by the embodiment of the present application, the blade assembly 100 of the blood pumping drive mechanism 10 can reciprocate axially and contract under the drive of the drive assembly 200, so as to switch itself alternately between the first form and the second form, thereby being able to perform blood pumping operations, wherein the reciprocating axial contraction and contraction of the blade 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 blade assembly 100 in the first form, the number of blades 110, the axial stroke of the blade assembly 100 in the pump housing 20, etc., so that the reciprocating axial contraction frequency of the blade assembly 100 can be slightly increased or not increased, and the reciprocating axial contraction frequency of the blade assembly 100 is avoided to be too large, so that the reciprocating axial contraction frequency of the blade 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 pumping drive mechanism 10 of the ventricular assist system provided in the present application can effectively reduce the shear force on blood cells and thus greatly eliminate 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.

[0096] In some embodiments of the present application, a movable first operating button (not shown in the drawings) may be provided on the handle mechanism 2. The pump housing 20 may be expanded or contracted by controlling the first operating button to push the conduit 30 forward or withdraw it backward, wherein 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 drawings), and the power mechanism 40 of the blood pump 1 may be provided on the handle mechanism 2 and connected to the second operating button. The power mechanism 40 may 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 button.

[0098] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described 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 above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A blood pump driving mechanism for a blood pump, characterized in that: include: A blade assembly, the blade assembly having a first shape and a second shape, wherein a maximum radial dimension of the blade assembly in the first shape is greater than a maximum radial dimension in the second shape; The driving assembly can drive the blade assembly to reciprocate and axially extend and retract, so that the blade assembly switches alternately between the first form and the second form, thereby enabling the blade assembly to perform a blood pumping operation.

2. The blood pumping drive mechanism according to claim 1, characterized in that: The blade assembly includes a plurality of blades connected in sequence from near to far. In the first form, each of the blades is unfolded, and in the second form, each of the blades is folded.

3. The blood pumping drive mechanism according to claim 2, characterized in that: The maximum radial dimensions of the plurality of blades in the first form decrease sequentially along the blood pumping direction.

4. The blood pumping drive mechanism according to claim 2, characterized in that: The paddle comprises a connected closed section and a hollow section, the closed section and the hollow section are arranged in sequence along the blood pumping direction, and the radial dimension of the connection between the closed section and the hollow section is the largest.

5. The blood pumping drive mechanism according to claim 4, characterized in that: The radial dimensions of the closed section in the first form and the second form gradually increase along the blood pumping direction, and the radial dimensions of the hollow section in the first form and the second form gradually decrease along the blood pumping direction.

6. The blood pumping drive mechanism according to claim 4, characterized in that: The closed section includes a first frame and a flow-blocking film, the flow-blocking film is covered on the first frame, and the first frame is connected to the hollow section; and / or, The hollow section includes a second frame connected to the closed section.

7. The blood pumping drive mechanism according to claim 6, characterized in that: The first frame is made of shape memory material, and when the first frame is in an initial state, the blade is in the first shape; and / or, The second frame is made of shape memory material, and when the second frame is in an initial state, the blade is in the first shape.

8. The blood pumping drive mechanism according to claim 2, characterized in that: The blade assembly further includes at least one connecting tube, which is disposed between two adjacent blades or at the proximal end of the blade at the nearest side.

9. The blood pumping drive mechanism according to claim 2, characterized in that: 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 proximal end and a distal end connected, the proximal end is movably sleeved in the outer tube, and the distal end is passed through each of the blades and connected to the farthest blade.

10. The blood pumping drive mechanism according to claim 9, characterized in that: The inner tube is a hypotube.

11. The blood pumping drive mechanism according to any one of claims 1 to 10, 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 developing member, which is disposed on the proximal side of the paddle assembly; The blood pumping drive mechanism further includes a second developing member, which is disposed at the distal side of the paddle assembly; The blood pumping drive mechanism also includes a protective coating, which is arranged on the surface of the blade assembly.

12. A blood pump, characterized in that: It comprises a pump housing, a catheter, a power mechanism and a blood pumping drive mechanism as claimed in any one of claims 1 to 11; The pump housing has a blood flow inlet and a blood flow outlet, the catheter is arranged on the proximal side of the pump housing, the paddle assembly of the blood pumping drive mechanism is arranged in the pump housing, the proximal end of the driving assembly of the blood pumping drive mechanism is connected to the power mechanism, and the power mechanism can drive the paddle assembly to reciprocate axially between the blood flow inlet and the blood flow outlet through the driving assembly.

13. A ventricular assist system, characterized in that: It comprises a handle mechanism and the blood pump as claimed in claim 12, wherein the proximal end of a catheter of the blood pump is connected to the handle mechanism.

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