Blood pump

Abstract

This application relates to a blood pump, which includes a drive unit and a housing. The drive unit drives blood flow. The housing is fitted around the periphery of the drive unit, and the proximal end of the housing is fixedly connected to the proximal end of the drive unit or a conduit of the blood pump. The inner circumferential surface of the housing and the drive unit are radially spaced to form a blood flow channel. The housing includes a first housing and a second housing. The proximal end of the first housing is fixedly connected to the drive unit or the conduit, and the distal end of the first housing is connected to the second housing, forming a cylindrical structure. The first housing has an inlet, and the second housing has an outlet, which communicates with the inlet through the blood flow channel. This design allows for a smaller axial dimension of the blood pump body, enabling the blood pump to pass through the path from the inferior vena cava (or superior vena cava) to the pulmonary artery, thus assisting the right ventricle in pumping blood into the pulmonary artery and reducing the risk of excessive expansion during right ventricular congestion.

Description

Technical Field

[0001] This application relates to the field of medical device technology, and in particular to a blood pump. Background Technology

[0002] An interventional blood pump, also known as an intracardiac blood pump or intravascular blood pump, can be inserted into a blood vessel and protruded into the patient's heart to function as a left ventricular assist device or a right ventricular assist device.

[0003] In traditional technologies, right ventricular assist pumps, used as right ventricular assist devices, can easily cause excessive expansion of the right ventricle when assisting the heart to pump blood, which is detrimental to the patient's health. Summary of the Invention

[0004] Based on this, this application provides a blood pump designed to assist the right ventricle in blood circulation and to solve the problem of excessive expansion of the right ventricle.

[0005] This application provides a blood pump, which includes a drive unit and a housing. The drive unit drives blood flow. The housing is fitted around the periphery of the drive unit, and the proximal end of the housing is fixedly connected to the proximal end of the drive unit or a conduit of the blood pump. The inner circumferential surface of the housing and the drive unit are radially spaced to form a blood flow channel. The proximal end of the housing has a liquid inlet, and the distal end of the housing has a liquid outlet, which communicates with the liquid inlet through the blood flow channel. The housing includes a first housing and a second housing. The proximal end of the first housing is fixedly connected to the drive unit or a conduit, and the distal end of the first housing is connected to the second housing, forming a cylindrical structure. The first housing has a liquid inlet, and the second housing has a liquid outlet.

[0006] In one embodiment, the first housing includes a first straight tube; the second housing includes a second straight tube coaxially disposed with the first straight tube, the second straight tube being abutted to the distal end of the first straight tube, the inner circumferential surface of the second straight tube being flush with the inner circumferential surface of the first straight tube along its axial direction; and the outer circumferential surface of the first straight tube being flush with the outer circumferential surface of the first straight tube along its axial direction.

[0007] In one embodiment, the first housing further includes a reducing pipe and a plurality of connecting arms connecting the first straight pipe and the reducing pipe; wherein the reducing pipe is sleeved on the outer periphery of the connection between the conduit and the drive unit, and is fixedly connected to at least one of the drive unit and the conduit; the plurality of connecting arms are arranged at intervals along the circumference of the first straight pipe, and two adjacent connecting arms form a liquid inlet.

[0008] In one embodiment, the connecting arm has a first connecting portion connected to a first straight pipe, and a second connecting portion connecting the first connecting portion and the reducing pipe; the second connecting portion is located on the outer peripheral surface of the reducing pipe, and adjacent second connecting portions are spaced apart by notches, which are connected to the liquid inlet along the axial direction of the first housing.

[0009] In one embodiment, a guide surface is provided on the side of the second connector facing the notch groove, and the distal portion of the guide surface extends to the side of the proximal end of the first connector. The guide surface has a first width in the radial direction of the variable diameter pipe, and the first width first increases and then decreases in the direction from the variable diameter pipe to the first straight pipe.

[0010] In one embodiment, the second housing further includes a distal end cap connected to the distal end of the second straight tube; the distal end cap is dome-shaped and covers the distal end of the second straight tube; the liquid outlet extends from the side wall of the second straight tube to the distal end cap.

[0011] In one embodiment, the distal cap includes a top wall and an arched wall arranged circumferentially along the top wall; wherein the top wall is axially opposite and spaced from the distal end of the drive unit to be connected to the pig tail tube of the blood pump; the arched wall is disposed at the periphery of the top wall and connected to a second straight tube; the outlet includes a first outlet area located on the second straight tube and a second outlet area located on the arched wall.

[0012] In one embodiment, the outlet has a first orifice wall defining a first outlet region and a second orifice wall defining a second outlet region; the second orifice wall has an inner edge that contacts the inner surface of the arched wall and an outer edge that contacts the outer surface of the arched wall, and the second orifice wall is inclined from its inner edge to its outer edge.

[0013] In one embodiment, the first hole wall has a second width along the radial direction of the second straight pipe, and the second hole wall has a third width along the radial direction of the arched wall, the third width being greater than the second width;

[0014] And / or, the first hole wall includes a transverse hole wall extending circumferentially along the second straight pipe, and arcuate hole walls located at both ends of the transverse hole wall; the second hole wall extends in a semi-circular shape along its length, and the two ends of the second hole wall are smoothly connected to the two arcuate hole walls respectively.

[0015] In one embodiment, the second hole wall has a middle portion adjacent to the top wall, and a first portion and a second portion located on both sides of the middle portion; the third width of the second hole wall located on the first portion gradually increases and then gradually decreases along the direction from the first portion to the middle portion; and / or, the third width of the second hole wall located on the second portion gradually increases and then gradually decreases along the direction from the second portion to the middle portion.

[0016] In one embodiment, the drive unit includes a motor and an impeller; the motor is at least partially located inside the first housing, with the proximal end of the motor fixed to the proximal end of the first housing; the impeller is located inside the second housing and connected to the distal end of the motor; and the distal end of the impeller extends into the inside of the distal end cover to be radially opposite to the liquid outlet.

[0017] In one embodiment, the second housing includes a second straight tube and a conical top connected to the distal end of the second straight tube; wherein, a liquid outlet is provided on the distal sidewall of the second straight tube; the conical top includes a hemispherical portion connected to the second straight tube, and a guide cone extending from the hemispherical portion to the distal end of the second straight tube, the diameter of the guide cone being gradually reduced in the direction from the second housing to the first housing.

[0018] In one embodiment, the drive unit includes a motor and an impeller; the motor is at least partially located inside the first housing, and the proximal end of the motor is fixed to the proximal end of the first housing; the impeller is located inside the second housing and connected to the distal end of the motor; the distal end of the impeller extends into the inside of the distal end cover and is radially opposite to the liquid outlet.

[0019] In one embodiment, the drive unit includes a motor and an impeller; the proximal end of the motor is connected to a duct, and the proximal end of the impeller is connected to the motor shaft; the maximum outer diameter of the motor is d1, the maximum outer diameter of the impeller is d2, d1 < d2; the maximum inner diameter of the casing is d3, △D1 = d3 - d1, △D2 = d3 - d2, 2*△D2 ≤ △D1 ≤ 4*△D2.

[0020] The blood pump provided in this application, by providing an inlet and an outlet on the casing and placing the drive unit inside the casing, creates a blood flow channel along the radial distance between the inner wall of the casing and the drive unit. This blood flow channel connects the inlet and outlet, allowing the casing length to be shortened to slightly longer than the drive unit (enough to accommodate the drive unit and enable its normal operation). This effectively shortens the axial length of the pump body, making the blood pump suitable for narrowing the delivery path between the right ventricle and the pulmonary artery. When used in the right ventricle of an interventional patient, the blood pump can pass through the right atrium, through the tricuspid valve, into the right ventricle, and through the pulmonary valve to partially extend into the pulmonary artery, so that the inlet of the blood pump is located within the right ventricle, and the outlet is located within the pulmonary artery. Compared to conventional blood pumps, the blood pump of this application can penetrate from the right ventricle into the pulmonary artery to assist in right ventricular decompression, reduce the risk of excessive expansion during right ventricular congestion, and improve the safety of the blood pump. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the anatomical structure of the human heart.

[0022] Figure 2 This is a schematic diagram of a blood pump used to assist the right ventricle in pumping blood, according to an embodiment of this application.

[0023] Figure 3 for Figure 2 The diagram shows a partial structural schematic of the blood pump.

[0024] Figure 4 for Figure 3 The blood pump shown is a cross-sectional view along line AA.

[0025] Figure 5 for Figure 4 A magnified view of blood pump B shown.

[0026] Figure 6 for Figure 4 A magnified view of the blood pump at point C.

[0027] Figure 7 for Figure 3 A schematic diagram of the blood pump from another perspective.

[0028] Figure 8 for Figure 3 The diagram shows an explosion of a blood pump.

[0029] Figure 9 for Figure 8 The diagram shows the structure of the first housing of the blood pump.

[0030] Figure 10 for Figure 9 A structural schematic diagram of the first housing from another perspective.

[0031] Figure 11 for Figure 10 The first housing shown is a cross-sectional view.

[0032] Figure 12 for Figure 8 The diagram shows the structure of the second housing of the blood pump.

[0033] Figure 13 for Figure 12 The second housing shown is a cross-sectional view.

[0034] Figure 14 for Figure 13 An enlarged view of point D in the second housing shown.

[0035] Figure 15 for Figure 8 Another structural schematic diagram of the second housing of the blood pump shown.

[0036] Figure 16 for Figure 8 Another structural schematic diagram of the second housing of the blood pump shown.

[0037] Figure 17 for Figure 3 A magnified view of the distal end of the blood pump body shown.

[0038] Figure 18 This is a schematic diagram of the structure of the second housing of the blood pump in another embodiment of this application.

[0039] Figure 19This is a size comparison diagram of the motor, impeller, and housing of the blood pump in another embodiment of this application.

[0040] Reference numerals: 10, Blood pump; 11, Pump body; 12, Catheter; 100, Shell; 110, Second shell; 1110, Second straight tube; 1111, Second insertion part; 1120, Distal cap; 1121, Arched wall; 1122, Top wall; 1122a, Guide wire hole; 1123, Separator wall; 1130, Outlet; 1131, First outlet area; 1132, Second outlet area; 1133, First hole wall; 1133a, Transverse hole wall; 1133b, Arc-shaped hole wall; 1134, Second hole wall; 1134a, Inner edge; 1134b, Outer edge; A1, First part; A2, Second part; A3, Middle part; 1140, Conical apex; 1141, Guide cone; 1142, Hemispherical part; 120, First shell; 1210, Second... 1211 First insertion part; 1220 Variable diameter tube; 1221 Fourth insertion part; 1230 Connecting arm; 1231 First connecting part; 1232 Second connecting part; 1232a First outer surface; 1232b Second outer surface; 1232c Side surface; 1232d Variable diameter surface; 1240 Inlet; 200 Drive unit; 210 Motor; 211 Third insertion part; 220 Impeller; 300 Blood flow channel; 20 Inferior vena cava; 21 Superior vena cava; 22 Right atrium; 23 Tricuspid valve; 24 Right ventricle; 25 Pulmonary valve; 25a Medial surface; 26 Pulmonary artery; 27 Pulmonary vein; 28 Left atrium; 29 Mitral valve; 30 Left ventricle; 31 Aortic valve; 32 Aorta. Detailed Implementation

[0041] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0042] In the description of this application, it should be understood that if 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.

[0043] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0044] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0045] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0046] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0047] In related technologies, interventional assistive devices, also known as blood pumps, are primarily used to insert into a patient's blood vessels to assist blood circulation. To facilitate understanding of the application of blood pumps, a brief explanation of the heart structure and blood flow direction is provided below. Please refer to... Figure 1 , Figure 1 This is an anatomical diagram of the human heart. Human blood circulation includes systemic circulation and pulmonary circulation. In systemic circulation, blood is ejected from the left ventricle (30) through the aortic valve (31) into the aorta (32). From there, it flows through the aorta to the capillaries throughout the body for substance exchange, transforming arterial blood into venous blood. This venous blood then returns to the right atrium (22) via the superior vena cava (21) and inferior vena cava (20). Next, blood from the right atrium (22) enters the right ventricle (24) through the tricuspid valve (23), and is then ejected from the right ventricle (24) through the pulmonary valve (25) into the pulmonary artery (26). From there, it flows through the pulmonary artery (26) to the pulmonary capillaries for gas exchange, transforming venous blood into arterial blood. Finally, this arterial blood returns to the left atrium (28) through the pulmonary veins (27). Blood from the left atrium (28) then enters the left ventricle (30) through the mitral valve (29). This circulation is called pulmonary circulation.

[0048] A common type of blood pump is the left ventricular assist pump (LVAP). This type of LVAP typically includes a drive unit and a cannula assembly. The cannula assembly has an outlet at its proximal end and an inlet at its distal end. The motor of the drive unit is fixed to the proximal end of the cannula assembly, and the impeller of the drive unit is arranged inside the cannula assembly and connected to the motor shaft. The length of this cannula assembly is usually several times the length of the drive unit, resulting in a relatively long axial length of the pump body. When the LVAP is applied to the left ventricle 30, it is typically passed through the aortic valve 31 from the aorta 32, with the inlet of the LVAP extending into the left ventricle 30, while the outlet remains within the aorta 32; that is, only the distal portion of the LVAP extends into the left ventricle 30. Thus, the LVAP assists the left ventricle 30 in pumping blood from the left ventricle 30 to the aorta 32. The path of the left ventricular assist pump from the ascending portion of the aorta 32 through the aortic valve 31 to enter the left ventricle 30 is relatively close to the same axial direction. Therefore, this left ventricular assist pump with a pump body of relatively long axial length can adapt to the pushing path of the left ventricle 30.

[0049] If a patient has functional impairment in right ventricle 24, a blood pump is also required to assist right ventricle 24 in pumping blood. Therefore, the application of a left ventricular assist pump (LVAP) to assist right ventricle 24 in pumping blood has been considered. However, the typical delivery path for a blood pump implanted in the right ventricle is from the inferior vena cava 20 or superior vena cava 21, through the right atrium, tricuspid valve 23, right ventricle 24, pulmonary valve 25, and finally to the pulmonary artery 26. This path is short, winding, and complex. Because the axial length of a traditional left ventricular assist pump is too long to pass through the right ventricle 24 delivery path, its application in right ventricle 24 is difficult.

[0050] Therefore, a right ventricular assist pump (LVAP) has emerged on the market to assist blood flow in the right ventricle 24. This LVAP is designed to be inserted into the inferior vena cava 20 via an incision in the patient's lower back or thigh, with both the inlet and outlet located within the inferior vena cava 20; that is, the outlet does not extend into the pulmonary artery 26. When the LVAP is activated, it only accelerates the flow of blood from the inferior vena cava 20 to the right atrium, and then into the right ventricle 24. However, it cannot assist the right ventricle 24 in pumping blood to the pulmonary artery 26 for decompression. This results in a significant defect: the right ventricle 24 is prone to over-inflation during congestion, posing a potential safety hazard to the patient.

[0051] Please see Figure 2 To address the aforementioned problems, this application provides a blood pump 10, which is primarily used as a right ventricular assist pump. The blood pump 10 extends from the right ventricle 24 into the pulmonary artery 26 to assist the right ventricle 24 in pumping blood into the pulmonary artery 26, thereby relieving pressure in the right ventricle 24. Of course, in other embodiments, the blood pump 10 can also be used as a left ventricular assist pump. It should be noted that in the field of medical device technology, the end of a medical device closer to the physician or operator is typically referred to as the proximal end, and the end farther from the physician or operator is referred to as the distal end.

[0052] Please see Figures 2 to 4This application provides a blood pump 10 for assisting blood delivery, comprising a housing 100 and a drive unit 200. The drive unit 200 drives blood flow; the housing 100 is fitted around the outer periphery of the drive unit 200, and the proximal end of the housing 100 is fixedly connected to the proximal end of the drive unit 200 or the conduit 12 of the blood pump 10 to stabilize the relative position of the drive unit 200 and the housing 100. The inner circumferential surface of the housing 100 and the drive unit 200 are radially spaced to form a blood flow channel 300; the proximal end of the housing 100 is provided with an inlet 1240, and the distal end of the housing 100 is provided with an outlet 1130, which communicates with the inlet 1240 through the blood flow channel 300. The blood pump 10 can pass sequentially through the right atrium 22, the right ventricle 22, and the pulmonary artery to extend into the pulmonary artery 26, such that the inlet 1240 is located in the right ventricle 22 and the outlet 1130 is located in the pulmonary artery 26. It should be noted that the radial direction refers to the radial direction of the drive unit 200.

[0053] Specifically, the drive unit 200 and the housing 200 constitute the pump body 11 of the blood pump 10, and the axial length of the blood pump 10 refers to the length of the pump body 11. Here, by housing the drive unit 200 entirely inside the housing 200, instead of arranging the motor 110 and the housing 200 axially (as in the arrangement of the motor and cannula assembly of a traditional left ventricular assist pump), the length of the housing 200 can be shortened to be slightly longer than the drive unit 200 (enough to accommodate the drive unit 200 and enable it to work normally). This greatly shortens the axial length of the pump body 11 of the blood pump 10, allowing the pump body 11 of the blood pump 10 to adapt to the short and winding push path of the right ventricle 24. Therefore, the distal end of the blood pump 10 of this application can pass through the right atrium 22, the right ventricle 24, and the pulmonary valve 25 in sequence to extend into the pulmonary artery 26, so that the inlet 1240 is located in the right ventricle 24, while the outlet 220a is located in the pulmonary artery 26.

[0054] Specifically, such as Figure 2 As shown, the Figure 2 This diagram illustrates the blood pump 10 of this application as a right ventricular auxiliary pump used to assist the right ventricle in pumping blood. Figure 2The dashed arrow F indicates the direction of blood flow. One of the pushing paths of the blood pump 10 is as follows: the pump body 11 of the blood pump 10 passes through the inferior vena cava 20 into the right atrium 22, then passes through the tricuspid valve 23 into the right ventricle 24 from the right atrium 22, and then passes through the pulmonary valve 25 from the right ventricle 24 to partially extend into the pulmonary artery 26, ensuring that the inlet 1240 of the blood pump 10 is located in the right ventricle 24, while the outlet 220a of the blood pump 10 is located in the pulmonary artery 26. Another delivery path of the blood pump 10 is that the pump body 11 of the blood pump 10 enters the right atrium 22 from the superior vena cava 21, then passes through the tricuspid valve 23 from the right atrium 22 into the right ventricle 24, and then passes through the pulmonary valve 25 from the right ventricle 24 to partially extend into the pulmonary artery 26, ensuring that the inlet 1240 of the blood pump 10 is located in the right ventricle 24, while the outlet 220a of the blood pump 10 is located in the pulmonary artery 26.

[0055] from Figure 1 and Figure 2 It is evident that the delivery path of the blood pump 10 from the inferior vena cava 20 or the superior vena cava 21 to the pulmonary artery 26 is characterized by a short path, numerous bends, and complex internal tissues. Because the pump body 11 of the blood pump 10 of this application has a relatively short axial length, the pump body 11 can pass through each bend of the shorter delivery path and bend upwards (or deflect) into the pulmonary artery 26 within the narrow right ventricle 24, greatly reducing the difficulty of the blood pump 10 entering the right ventricle 24 and improving the smoothness of the blood pump 10 traversing the delivery path.

[0056] When the blood pump 10 is turned on, the drive unit 200 operates and drives blood through the right atrium 22 into the right ventricle 24. The blood in the right ventricle 24 is then drawn into the blood flow channel 41 by the inlet 1240 of the blood pump 10. The blood in the blood flow channel 40 continues to be driven by the impeller 120 to flow to the outlet 1130, and finally the blood is discharged from the outlet 1130 into the pulmonary artery 26. Thus, the blood pump 10 of this application can extend from the right ventricle 24 to the pulmonary artery 26 to assist in depressurization of the right ventricle 24, thereby reducing the risk of excessive expansion during the congestion of the right ventricle 24 and improving the safety of the blood pump 10 during use. In the accompanying drawings of this application, M1 and M2 are two points on the axis of the pump body 11 of the blood pump 10. The dashed lines M1 and M2 can represent the axis or axial direction of the pump body 11. The direction from M1 to M2 is the direction along the blood pump 10 from the proximal end to the distal end. Conversely, the direction from M2 to M1 is the direction along the blood pump 10 from the distal end to the proximal end.

[0057] It is understandable that, since the drive unit 200 is housed inside the housing 200 and the blood flow channel 300 is formed between the inner peripheral wall of the housing 200 and the drive unit 200, the length of the housing 200 is equivalent to the axial length of the pump body 11. The length of the housing 200 can be designed to be only slightly longer than the drive unit 200 (to accommodate the drive unit and enable it to work properly), instead of being designed to be several times longer than the drive unit 200 as in traditional cannula assemblies.

[0058] Please see Figure 3 and Figure 8 The blood pump 10 also includes a catheter 12, the distal end of which is fixedly connected to the proximal end of the drive unit 200. The catheter 12 contains supply lines such as wires and flushing tubing (not shown in the figure). The proximal end of the housing 200 can be directly fixed to the catheter 12, or the proximal end of the housing 200 can be fixed to the proximal end of the drive unit 200. Since the catheter 12 is typically deformable to fit into blood vessels, its axial size usually has little impact on the difficulty of implanting the blood pump 10 within the heart 20. That is, the ability to design a smaller axial size for the blood pump 10 mainly refers to the axial size of the pump body 11. The portion of the blood pump 10 located within the heart 20 mainly refers to the pump body 11. This application is configured such that the axial length of the pump body 11 of the blood pump 10 can be designed to be smaller, so that after the pump body 11 of the blood pump 10 enters the right ventricle 24, it can bend (or deflect) upward in the right ventricle 24 to pass through the pulmonary valve 25, so that the inlet 1240 of the blood pump 10 is located in the right ventricle 24, while the outlet 1130 of the blood pump 10 can pass through the pulmonary valve 25 into the pulmonary artery 26.

[0059] Please see Figure 4 and Figure 8 In one embodiment, the housing 100 includes a first housing 120 and a second housing 110; the proximal end of the first housing 120 is fixedly connected to the drive unit 200 or the conduit 12, and the distal end of the first housing 120 is connected to the proximal end of the second housing 110, thus forming a cylindrical structure with the second housing 110. The first housing 120 is provided with the liquid inlet 1240; the second housing 110 is provided with the liquid outlet 1130.

[0060] Specifically, the proximal end of the first housing 120 can be fixed to the proximal end of the drive unit 200 or the distal end of the conduit 12, so that the first housing 120 can support the drive unit 200 and ensure that the drive unit 200 can stably drive blood flow within the blood flow channel 300. By connecting the first housing 120 and the second housing 110 to form a cylindrical structure, a straight blood flow channel 300 can be formed inside the sleeve 100, which means that the blood flow channel 300 can extend in the same direction as the axis M1M2 of the sleeve 100, avoiding the blood flow channel 300 from being meandering and increasing the resistance to blood flow, so that blood can flow smoothly along the blood flow channel 300 to the outlet 1130. Furthermore, by setting the housing 100 as a splicing structure composed of the second housing 110 and the first housing 120, when assembling the blood pump 10, the drive unit 200 can be connected to the proximal end of the first housing 120 firstly, and then the second housing 110 can be fitted over the drive unit 200 from the other side to splice with the first housing 120. This makes the assembly of the drive unit 200 and the housing 100 more convenient.

[0061] Please see Figure 7 and Figure 8 In one embodiment, the first housing 120 includes a first straight tube 1210, a reducing tube 1220, and a plurality of connecting arms 1230; the plurality of connecting arms 1230 connect the first straight tube 1210 and the reducing tube 1220. The first straight tube 1210 is connected to a second straight tube 1110; the reducing tube 1220 is sleeved on the outer periphery of the connection between the conduit 12 and the drive unit 200, and is fixedly connected to at least one of the conduit 12 and the drive unit 200; the plurality of connecting arms 1230 are spaced apart along the circumferential direction of the first straight tube 1210, and an inlet 1240 is formed between every two adjacent connecting arms 1230, thereby forming a plurality of inlets 1240. The plurality of inlets 1240 are spaced apart along the circumferential direction of the first straight tube 1210, allowing blood to flow in from various circumferential angles.

[0062] Understandably, the first straight tube 1210 is arranged in a straight tube shape so that its inner circumferential surface forms a cylindrical surface, reducing the fluid resistance of the blood flow channel 300. The reducing tube 1220, on the other hand, is conical. By fitting the reducing tube 1220 around the connection between the catheter 12 and the drive unit 200, the connection can be enclosed within the reducing tube 1220, preventing the adhesive at the connection from being washed away by blood. The reducing tube 1220 has two openings, one of which can be press-fitted with the distal outer circumferential surface of the catheter 12, and the other opening can be press-fitted with the proximal outer circumferential surface of the drive unit 200. The first straight tube 1210, the reducing tube 1220, and the connecting arm 1230 can be integrally formed.

[0063] Optionally, the second housing 110 includes a second straight tube 1110 coaxially arranged with the first straight tube 1210, the distal end of the second straight tube 1110 being connected to the first straight tube 1210; the inner circumferential surface of the second straight tube 1110 is flush with the inner circumferential surface of the first straight tube 1210 along its axial direction; the outer circumferential surface of the second straight tube 1110 is flush with the outer circumferential surface of the first straight tube 1210 along its axial direction. The axial direction refers to the axial direction of the first straight tube 1210, that is, the circumferential direction of the second straight tube 1110. Specifically, the second straight tube 1110 is also arranged in a straight tube shape, such that the inner circumferential surface of the second straight tube 1110 also forms a cylindrical surface, thereby the second straight tube 1110 and the first straight tube 1210 are assembled into a regular cylinder. This design allows the outer circumference of the casing 100 to be smooth and regular, which can reduce damage to human tissues during the implantation of the blood pump 10. On the other hand, the inner circumference of the casing 100 is also relatively smooth and regular, which can reduce the resistance of the blood flow channel 300 to the fluid, reduce the kinetic energy loss of blood flowing in the blood flow channel 300, improve the pumping efficiency, and reduce damage to blood cells.

[0064] Please see Figures 4 to 5 Optionally, for the assembly method of the first straight tube 1210 and the second straight tube 1110, a first insertion part 1211 is provided radially outwardly recessed on the inner circumferential surface of the distal end of the first straight tube 1210, and a second insertion part 1111 is provided radially inwardly recessed on the outer circumferential surface of the proximal end of the second straight tube 1110. The first insertion part 1211 and the second insertion part 1111 are inserted into each other, so that the blood flow channel 300 is relatively closed. After the first straight tube 1210 and the second straight tube 1110 are inserted into each other, the inner circumferential surfaces of the first straight tube 1210 and the second straight tube 1110 are located on the same curved surface; the outer circumferential surfaces of the first straight tube 1210 and the second straight tube 1110 are also located on the same curved surface. In this way, the inner and outer circumferential surfaces of the casing 100 can be made smooth and regular.

[0065] Please see Figure 7In one embodiment, the connecting arm 1230 of the first housing 120 includes a first connecting portion 1231 connected to the first straight tube 1210, and a second connecting portion 1232 connecting the first connecting portion 1231 and the reducing tube 1220; the second connecting portion 1232 is located on the outer peripheral surface of the reducing tube 1220, and a notch 1241 is formed between two adjacent second connecting portions 1232, and the notch 1241 is connected to the liquid inlet 1240 along the axial direction of the first housing 120. Thus, when the drive unit 200 generates suction, a portion of blood F3 is drawn radially from the circumference of the first housing 120 into the inlet 1240, and then continues to be driven by the drive unit 200 to switch to axial flow into the blood channel 300; another portion of blood F4 can enter the inner side of the inlet 1240 axially from the notch 1241, and push the portion of blood F3 entering from the inlet 1240 to flow axially, thereby accelerating the flow of blood F3 into the blood channel 300, thereby effectively increasing the blood flow rate entering from the inlet 1240 and improving the pumping efficiency of the blood pump 10.

[0066] Please see Figure 7 and Figure 9 In one embodiment, the side of the second connecting portion 1232 facing the notch 1241 is provided with a guide surface 1242, which guides blood from the notch 1241 axially into the inner side of the inlet 1240. Specifically, as... Figure 10 and Figure 11 As shown, the outer diameter of the first straight pipe 1210 is larger than the outer diameter of the reducing pipe 1220. Let the outer diameter of the first straight pipe 1210 be R1 and the outer diameter of the reducing pipe 1220 be R2. Then R1 > R2. This causes the second connecting part 1232 to extend obliquely from the first connecting part 1231 toward the outer peripheral surface of the reducing pipe 1220, so that the side of the second connecting part 1232 can form the oblique flow guide surface 1242.

[0067] Optionally, the distal portion of the guide surface 1242 extends to the side of the proximal end of the first connecting portion 1231 to extend the axial length of the guide surface 1242. This allows the guide surface 1242 to continue guiding the blood that has completely passed through the notch 1241 a short distance towards the inside of the inlet 1240, improving the guiding effect. Further, the guide surface 1242 has a first width L1 in the radial direction along the reducer 1220, which first increases and then decreases in the direction from the reducer 1220 to the first straight pipe 1210. It is understood that the first width L1 should satisfy: L1 ≤ R1 - R2.

[0068] Specifically, the guide surface 1242 is roughly prismatic in shape, such that its first width L1 first increases and then decreases along the direction from the reducer 1220 to the first straight pipe 1210. The guide surface 1242 guides blood F4 from the notch 1241 into the inner side of the inlet 1240, accelerating blood flow and improving pumping efficiency. Furthermore, since there is a radial difference between the first straight pipe 1210 and the reducer 1220, by first increasing and then decreasing the guide surface 1242 of the second connecting part 1232, it is equivalent to increasing the radial thickness of the second connecting part 1232 and then decreasing it. This not only allows the second connecting part 1232 to fit between the first straight pipe 1210 and the reducer 1220, but also improves the structural strength of the connecting arm 1230.

[0069] It is understandable that L1≤R1-R2, meaning the maximum thickness of the second connecting part 1232 can be equal to the difference between the inner diameter of the first straight pipe 1210 and the outer diameter of the reducer 1220. Therefore, the second connecting part 1232 neither extends beyond the outer circumferential surface of the first straight pipe 1210 nor protrudes inward from the outer circumferential surface of the reducer 1220. This arrangement allows the second connecting part 1232 to be more appropriately connected between the first straight pipe 1210 and the reducer 1220.

[0070] Please see Figures 9 to 11 In one embodiment, the second connecting portion 1232 has a first outer surface 1232a, a second outer surface 1232b, a side surface 1232c, a variable diameter surface 1232d, and an adapter surface (not shown in the figures, the same below). The first outer surface 1232a and the second outer surface 1232b are connected to form the outer surface of the second connecting portion 1232. The first outer surface 1232a and the outer peripheral surface of the first straight pipe 1210 are located on the same curved surface. The side of the second outer surface 1232b away from the first outer surface 1232a is radially deflected inward to adapt to the radial difference between the first straight pipe 1210 and the variable diameter pipe 1220. Each second connecting portion 1232 has two side surfaces 1232c, which are respectively connected to opposite sides of the outer peripheral surface of the second connecting portion 1232. The side surfaces 1232c form a guide surface 1242. One side of the reducing surface 1232d is connected to the connecting portion 1232. The side of the reducing surface 1232d away from the connecting portion 1232 is radially deflected inward to accommodate the radial difference between the first straight pipe 1210 and the reducing pipe 1220. The fitting surface is connected to the reducing surface 1232d and fits against the outer periphery of the reducing pipe 1220. The reducing surface 1232d is aligned with at least a portion of the first outer surface 1232a to gradually increase the thickness of the second connecting portion 1232. The fitting surface is aligned with the second outer surface 1232b to gradually decrease the thickness of the second connecting portion 1232.

[0071] Please see Figures 9 to 11In one embodiment, the first connecting portion 1231 can be smoothly connected to the reducing tube 1220; the second connecting portion 1232 can also be smoothly connected to the first straight tube 1210. This avoids the formation of sharp edges around the second connecting portion 1232, preventing scratching of blood cells. Specifically, among the connecting portion 1232, the reducing tube 1220, the first outer surface 1232a, the second outer surface 1232b, the side surface 1232c, the reducing surface 1232d, and the adapter surface, any interconnected components can be smoothly connected using rounded corners or other methods to reduce sharp edges on the outer periphery of the blood pump 10 and prevent damage to the inner wall of the blood vessel.

[0072] Please see Figure 3 , Figure 4 and Figure 8 In one embodiment, the second housing 110 includes a second straight tube 1110 and a distal end cap 1120. The proximal end of the second straight tube 1110 is connected to the first housing 120. The distal end cap 1120 is connected to the distal end of the second straight tube 1110, and the distal end cap 1120 covers the distal end opening of the second straight tube 1110 in a dome shape. The distal end cap 1120 is dome-shaped, that is, the distal end cap 1120 is set as a hollow arch, for example, the distal end cap 1120 can be a hemispherical hollow structure or a semi-elliptical hollow structure.

[0073] Furthermore, the outlet 1130 of the blood pump 10 extends from the side wall of the second straight tube 1110 to the distal end cap 1120, meaning that a portion of the area containing the outlet 1130 corresponds to the axial direction of the second straight tube 1110. Therefore, a portion of the blood flowing along the axial direction of the second straight tube 1110 can flow directly out from the outlet 1130 without being redirected, reducing kinetic energy loss during blood flow and improving the pumping efficiency of the blood pump 10. This also relatively improves the working efficiency of the drive unit 200, reduces the energy consumption of the blood pump 10, and extends the usage time of the blood pump 10 after a single charge. Optionally, the second straight tube 1110 and the distal end cap 1120 are integrally formed.

[0074] Please see Figure 4 , Figure 12 and Figure 13In one embodiment, the distal cap 1120 includes a top wall 1122 and an arched wall 1121 arranged circumferentially along the top wall 1122; the distal cap 1120 is connected to the second straight tube 1110 through the arched wall 1121. The top wall 1122 is axially opposite to and spaced from the distal end of the drive unit 200, and the top wall 1122 can be connected to the pig tail tube of the blood pump 10. Specifically, the top wall 1122 can be connected to the pig tail tube (not shown in the figure) of the blood pump 10. The top wall 1122 can be part of the most distal end of the blood pump 10. The top wall 1122 is connected to the pig tail tube, and the guiding effect of the pig tail tube facilitates the movement of the blood pump 10 in the tortuous blood vessels, and the structural fixing effect of the pig tail tube facilitates the fixation of the distal end of the blood pump 10 in the pulmonary artery 26.

[0075] The top wall 1122 can be a planar wall perpendicular to the axis M1M2 or a spherical wall. In this embodiment, the top wall 1122 is arranged radially along the second straight pipe 1110, and the diameter of the top wall 1122 is smaller than the inner diameter of the second straight pipe 1110. The outer surface of the top wall 1122 is a plane, and the inner surface of the top wall 1122 is a sphere. An arched wall 1121 is arranged around the circumference of the top wall 1122 and connects the top wall 1122 and the second straight pipe 1110. That is, the arched wall 1121 is arched in all directions to connect the second straight pipe 1110 and the top wall 1122, which have a radial dimensional difference.

[0076] Combination Figure 13 In one embodiment, the outlet 1130 extends from the side wall of the second straight pipe 1110 to the arched wall 1121 of the distal end cap 1120. It is understood that since the arched wall 1121 connects the second straight pipe 1110 and the top wall 1122, which have a radial dimensional difference, the arched wall 1121 has a certain extension area in the radial direction of the blood pump 10. Therefore, by extending the outlet 1130 from the side wall of the second straight pipe 1110 to the arched wall 1121 of the distal end cap 1120, on the one hand, the outlet 1130 has a larger distribution area; on the other hand, it also provides a certain extension area in the radial direction, allowing a portion of the blood flowing axially along the second straight pipe 1110 to flow out from the outlet 1130 with almost no turning, thereby reducing kinetic energy loss during blood flow and improving the pumping efficiency of the blood pump 10.

[0077] Please see Figure 12 and Figure 13In one embodiment, the outlet 1130 includes a first outlet region 1131 and a second outlet region 1132. The first outlet region 1131 is located on the second straight pipe 1110, and the second outlet region 1132 is located on the distal end cap 1120. A portion of blood F1 can be discharged radially from the first outlet region 1131. Since the arched wall 1121 is an arch that curves and retracts radially inward, and the second outlet region 1132 is located on the arched wall 1121, a portion of blood F2 flowing axially in the second straight pipe 1110 can flow directly out axially from the second outlet region 1132 without changing direction. This minimizes the kinetic energy loss of blood F2 and increases the flow rate of blood F2, thereby effectively improving the pumping efficiency of the blood pump 10.

[0078] Please see Figure 12 and Figure 15 Furthermore, the outlet 1130 also has a first orifice wall 1133 defining the first outlet region 1131 and a second orifice wall 1134 defining the second outlet region 1132. The first orifice wall 1133 includes a transverse orifice wall 1133a extending circumferentially along the second straight pipe 1110 and arcuate orifice walls 1133b located at both ends of the transverse orifice wall 1133a; the second orifice wall 1134 extends in a semi-circular shape along its length direction, and the two ends of the second orifice wall 1134 are smoothly connected to the arcuate orifice walls 1133b at both ends of the first orifice wall 1133.

[0079] Specifically, since the second straight tube 1110 is straight, by forming the first orifice wall 1133 with a transverse orifice wall 1133a and arc-shaped orifice walls 1133b at both ends, the first orifice wall 1133 can define a first outlet region 1131 with a large area on the second straight tube 1110, increasing the blood flow area and making the boundary of the first outlet region 1131 smoother, thus reducing damage to the blood. Similarly, since the arched wall 1121 is arched, the second orifice wall 1134 is semi-circular along its extension direction, which allows the second orifice wall 1134 to define a second outlet region 1132 with a large area on the arched wall 1121, increasing the blood flow area and making the boundary of the second outlet region 1132 smoother, thus reducing damage to the blood.

[0080] Please see Figures 12 to 14In one embodiment, the first orifice wall 1133 has a second width L2 radially along the second straight pipe 1110, and the second orifice wall has a third width L3 radially along the arched wall 1121. The third width L3 is greater than the second width L2, i.e., L3 > L2. As mentioned above, the distal end cap 1120 covers the distal end of the second straight pipe 1110; therefore, the blood flowing towards the distal end along the second straight pipe 1110 will change from axial flow to radial flow under the guidance of the distal end cap 1120, so the distal end cap 1120 needs to withstand a relatively large blood flow impact. Therefore, setting the third width L3 of the orifice wall surface of the second outlet region 1132 of the distal end cap 1120 relatively large can improve the structural strength of this region. At the same time, the second outlet region 1132 needs to accommodate the large amount of blood flow after the change, so setting the width of the orifice wall surface of the second outlet region 1132 relatively large can provide more guidance for the blood, thereby improving the smoothness of the blood flowing out of the second outlet region 1132 after the change.

[0081] Please see Figure 13 , Figure 14 and Figure 16 In one embodiment, the second hole wall 1134 has an inner edge 1134a that contacts the inner surface of the arched wall 1121, and an outer edge 1134b that contacts the outer surface of the arched wall 1121. The second hole wall 1134 is inclined from the inner edge 1134a to the outer edge 1134b. That is, the projections of the inner edge 1132a and the outer edge 1132b onto a plane perpendicular to the axial direction of the second straight tube 1110 do not coincide.

[0082] like Figure 16 As shown, the plane perpendicular to the axial direction of the second straight pipe 1110 is denoted as the projection plane PL. On the projection plane PL, the projection of the inner edge 1134a of the second hole wall 1134 onto the projection plane PL is called the first projection, and the projection of the outer edge 1134b onto the projection plane PL is called the second projection. The first projection is located between the second projection and the axis M1M2. With this configuration, when blood in the central region of the second housing 110 flows towards the top wall 1122, this portion of blood can flow radially from the top wall 1122 to the inner edge 1134a of the second hole wall 1134, then be guided by the second hole wall 1134 and flow along the wall attached to the second hole wall 1134, and flow to the outer edge 1134b of the second hole wall 1134, and finally separate from the outer edge 1134b and be discharged from the outlet 1130. That is, the second orifice wall 1134 can guide the blood flowing through the second outlet area 1132 from the inner edge 1134a to the outer edge 1134b, so as to reduce the resistance of the second outlet area 1132 to discharge blood and improve the pumping efficiency.

[0083] Of course, in another embodiment, the first projection and the second projection can be set to coincide. In this case, the second hole wall 1134 is perpendicular to the projection plane PL. In this case, the second hole wall 1134 can guide blood to be discharged from the outlet 1130 along the axial direction of the second housing 110. In yet another embodiment, the second projection is located between the first projection and the axis M1M2. In this case, the outer surface area of ​​the arched wall 1121 is smaller than the inner surface area of ​​the arched wall 1121. During the blood pump 10 intervention in the blood vessel, the contact area between the distal end of the second housing 110 (such as the position of the arched wall 1121) and the inner wall of the blood vessel is smaller, so as to reduce the resistance of the distal end of the second housing 110 to intervene in the blood vessel and make the intervention of the blood pump 10 smoother.

[0084] Please see Figure 14 , Figure 16 and Figure 17 In one embodiment, the inner edge 1134a of the second hole wall 1134 is formed by a first arc C1 along its length. The second hole wall 1134 has a third width L3 radially along the distal end cap 1120, that is, the third width L3 is the hole wall width of the second hole wall 1134 from the inner edge 1134a to the outer edge 1134b along the normal direction of the first arc C1. The third width L3 of the second hole wall 1134 gradually increases and then gradually decreases from both ends to the middle position. Specifically, the second hole wall 1134 includes a middle portion A3 adjacent to the top wall 1122, and a first portion A1 and a second portion A2 located on both sides of the middle portion A3. The third width L3 of the second hole wall 1134 located on the first portion A1 gradually increases and then gradually decreases along the direction from the first portion A1 to the middle portion A3. And / or, the third width L3 of the second hole wall 1134 located on the second portion A2 gradually increases and then gradually decreases along the direction from the second portion A2 to the middle portion A3.

[0085] Taking the first part A1 as an example, the first part A1 has a proximal endpoint P1 and a midpoint P2; the middle part A3 has a distal endpoint P3, and the midpoint P2 is located at the midpoint between the proximal endpoint P1 and the distal endpoint P3. The third width L3 of the second hole wall 1134 located on the first part A1 gradually increases from the proximal endpoint P1 to the midpoint P2, and then gradually decreases from the midpoint P2 to the distal endpoint P3. The second part A2 can be set with reference to the first part A1, or in other words, the second part A2 and the first part A1 are symmetrically set with respect to the middle part A3.

[0086] like Figure 13 As shown, for the blood pumped by blood pump 10, a portion of the blood F located in the peripheral region of impeller 220 21 It will be discharged from the area between the proximal endpoint P1 and the midpoint P2; there is also a portion of blood F near the central region of impeller 220. 22Due to the obstruction of the top wall 1122, the blood F will be radially deflected along the top wall 1122 and discharged from the area between the midpoint P2 and the distal end P3. 22 There may be kinetic energy loss during the deflection process. Therefore, in this embodiment, as... Figure 17 As shown, by gradually increasing and then decreasing the third width L3 of the second hole wall 1134 located on the first part A1 and the second part A2 along the direction from the proximal end to the distal end, the third width L3 of the second hole wall 1134 located on the middle part A3 is smaller, while the third width L3 located near the midpoint P2 of the first part A1 and the second part A2 is larger. Combined with the arcuate effect of the inner edge 1134a, the blood flow F 21 The axial component velocity increases, causing blood F 21 The blood tends to flow out from the region where the midpoint P2 is located, which not only prolongs the flow of blood F 21 The distance derived along the axial direction makes the blood F 21 It is expelled to more distant locations and can also increase blood flow. 21 The flow rate; thus, blood F 21 Increased flow will create negative pressure in its vicinity, affecting blood flow. 22 It can supply blood F even before it gets close to the top wall 1122. 21 Slightly deflected and flowed into the bloodstream F 21 This reduces the amount of blood F rushing towards the top wall 1122. 22 The flow rate, thereby reducing blood F 22 The energy loss resulting from the collision with the top wall 1122. The same applies to Part A2, so it will not be elaborated further.

[0087] Please see Figure 13 and Figure 14 In one embodiment, the arched wall 1121 includes a partition wall 1123 located between two adjacent outlets 1130. The partition wall 1123 has a wall thickness in the radial direction of the distal cap 1120, which increases first and then decreases from the connection between the partition wall 1123 and the second straight pipe 1110 to the top wall 1122. In this embodiment, this is configured so that the middle portion of the partition wall 1123 has a greater thickness. This facilitates a larger width near the midpoint P2 of the second orifice wall 1134, resulting in a larger flow guiding area for the orifice wall surface of the second outlet region 1132 near the P2 position. Furthermore, it improves the structural strength of the distal cap 1120 and reduces the possibility of deformation of the distal cap 1120 due to blood flow impact.

[0088] Please see Figure 8 and Figure 12In one embodiment, the top wall 1122 has a guide wire hole 1122a for a guide wire to pass through. The guide wire passes through the guide wire hole 1122a to assist in the implantation of the blood pump 10, and blood can also flow into the blood pump 10 through the guide wire hole 1122a. The inner surface of the top wall 1122 is shaped like a second arc C2, and the side of the second arc C2 near the guide wire hole 1122a is located at the distal end relative to the side away from the guide wire hole 1122a. It can be understood that the blood pumped by the blood pump 10 flows from the proximal end to the distal end. By setting the inner circumferential surface of the top wall 1122 to be shaped like a second arc C2, the inner circumferential surface of the top wall 1122 acts like a funnel, which can guide the blood to flow into the guide wire hole 1122a, thereby improving the smoothness of blood flow into the guide wire hole 1122a. The thickness H of the top wall 1122 can be set to gradually decrease along the direction from the end of the partition wall 1123 to the guide wire hole 1122a, so that the inner circumferential surface of the top wall 1122 is set as an arc. H can refer to the distance from the inner surface to the outer surface of the top wall 1122 along the normal direction of the second arc C2.

[0089] Please see Figure 4 and Figure 8 In one embodiment, the drive unit 200 includes a motor 210 and an impeller 220. The motor 210 is located inside the first housing 120, and the proximal end of the motor 210 is fixedly connected to the proximal end of the first housing 120; the impeller 220 is located inside the second housing 110 and is connected to the distal end of the motor 210.

[0090] Specifically, the distal end of the motor 210 is connected to the impeller 220, and the motor 210 can drive the impeller 220 to rotate, thereby driving blood flow. Traditional drive units require a separate proximal end cap at the proximal end of the motor 210 to enclose the connection between the motor 210 and the catheter 12. In this embodiment, the reducing tube 1220 of the first housing 120 can be directly used as the proximal end cap of the motor 210. Since the reducing tube 1220 is fitted around the outer periphery of the connection between the motor 210 and the catheter 12, it can enclose the connection. Furthermore, the two openings of the reducing tube 1220 are interference-fitted with the outer peripheral surface of the proximal end of the motor 210 and the outer peripheral surface of the distal end of the catheter 12, respectively, allowing the relatively rigid motor 210 and the relatively flexible catheter 12 to be stably connected. This configuration also simplifies the overall structure of the blood pump 10 and makes it more compact, improving the convenience of implanting and fixing the blood pump 10 in the human body and reducing the negative impacts of implantation and fixation on the human body.

[0091] Please see Figure 4 , Figure 7 and Figure 9In one embodiment, the reducing pipe 1220 of the first housing 120 can be sleeved and connected to the proximal end of the motor 210. The outer peripheral surface of the reducing pipe 1220 and the outer peripheral surface of the motor 210 are located on the same curved surface, that is, the outer peripheral surface of the reducing pipe 1220 and the outer peripheral surface of the motor 210 are flush with each other along the axial direction. Specifically, the outer peripheral surface of the reducing pipe 1220 forms the bottom of the notch groove 1241. By flushing the outer peripheral surface of the reducing pipe 1220 with the outer peripheral surface of the motor 210 along the axial direction, the joint between the two is made smoother and more regular, reducing blood flow resistance. In this way, the blood F4 flowing in from the notch groove 1241 can transition more smoothly from the outer peripheral surface of the reducing pipe 1220 to the outer peripheral surface of the proximal end of the motor 210 along the axial direction, effectively improving the blood flow rate.

[0092] Please continue reading. Figure 4 , Figure 6 and Figure 7 Optionally, the outer peripheral surface of the motor 210 is recessed radially inward on its proximal end, providing a third insertion portion 211; the inner peripheral surface of the reducer 1220 is provided radially outward on its distal end. The third insertion portion 211 and the fourth insertion portion 1221 are inserted into each other, and after insertion, the outer peripheral surface of the reducer 1220 and the outer peripheral surface of the motor 210 are located on the same curved surface. This makes the joint between the outer peripheral surface of the reducer 1220 and the outer peripheral surface of the motor 210 smooth and regular, which helps to reduce blood flow resistance.

[0093] Furthermore, the distal end of the impeller 220 extends into the inner side of the distal end cover 1120 of the second housing 110, so as to be radially opposite to the outlet 1130. In this way, when the impeller 220 rotates, it can directly and effectively drive the blood to flow out of the outlet 1130. Of course, other alignment relationships between the impeller 220 and the outlet 1130 can also be set according to the actual dimensions of the impeller 220 and the outlet 1130.

[0094] Please see Figure 19 In one embodiment, the maximum outer diameter of the motor 210 is d1, and the maximum outer diameter of the impeller 220 is d2, where d1 < d2. That is, a relatively large impeller 220 can be driven to rotate by a relatively small motor 210, thereby increasing the output power of the impeller 220 and improving the pumping efficiency of the pump.

[0095] Understandably, in traditional technologies, the motor of a blood pump is usually not located inside the housing, but rather its outer surface is part of the blood pump's outer surface. Since the impeller needs to create a stable blood flow, it is typically installed within the outlet pipe. Blood pumps are usually regular cylindrical structures, meaning the outer diameter of the outlet pipe is approximately the same as the outer diameter of the motor. However, in the embodiments of this application, by arranging both the motor 210 and the impeller 220 within the housing 100, and with the motor 210 and the inner circumferential surface of the housing 100 forming a blood flow channel 300 for stable blood flow, the radial dimension of the impeller 220 can be designed to be larger than that of the motor 210, thereby increasing the output power of the impeller 220 and improving the pumping efficiency. It should be noted that the impeller 220 is not a regular cylindrical structure. The radial dimension of the impeller 220 mentioned in the embodiments refers to the radial dimension of the approximately cylindrical rotating surface formed when the impeller 220 rotates. It can be understood that the maximum outer diameter of the impeller 220 is also the outer diameter of the rotating surface. In one embodiment, the maximum inner diameter of the casing 100 is d3. Therefore, we can set △D1 = d3 - d1, △D2 = d3 - d2, and 2 * △D2 ≤ △D1 ≤ 4 * △D2.

[0096] Please see Figure 18 This application also provides another structural type of the second housing 110. In this embodiment, the second housing 110 includes a second straight tube 1110 and a conical apex 1140. The proximal end of the second straight tube 1110 is connected to the first housing 120, and a liquid outlet 1130 is provided on the distal sidewall of the second straight tube 1110. The conical apex 1140 is connected to the distal end of the second straight tube 1110, and the conical apex 1140 has a guide cone 1141 extending into the distal end of the second straight tube 1110. The diameter of the guide cone 1141 gradually decreases along the direction from the second housing 110 to the second housing 120. In this way, the outer surface of the guide cone 1141 can guide the blood located radially inward in the second straight tube 1110 to flow radially outward toward the liquid outlet 1130, and from the liquid outlet 1130 flows into the blood pump 10. Optionally, the cone apex 1140 further includes a hemispherical portion 1142, which is connected to the distal end of the guide cone 1141. The hemispherical portion 1142 is axially offset from the outlet 1130. The hemispherical portion 1142 has an outer spherical surface, which can guide the blood flowing out of the outlet 1130 to quickly fill the central region of the distal end of the blood pump 10.

[0097] Please see Figure 3In one embodiment, the housing 200 has a first length K along the axial direction of the drive unit 100. This first length K allows the blood pump 10 to pass through the right atrium 22, right ventricle 24, and pulmonary valve 25 to extend into the pulmonary artery 26, such that the inlet 1240 is located within the right ventricle 24, while the outlet 220a is located within the pulmonary artery 26. Since the drive unit 100 and the housing 200 constitute the pump body 11 of the blood pump 10, and the drive unit 100 is located inside the housing 200, the first length K of the housing 200 corresponds to the axial length of the pump body 11 of the blood pump 10. It is understood that the size or anatomical shape of the tissues within the push path of the right ventricle 24 varies slightly among different patients; for example, the size or distance of the tissues within the push path of the right ventricle differs between young and elderly patients, and the requirements for the first length K also differ. Therefore, in practical applications, the length of the first length K should be set according to the patient's actual condition.

[0098] Optionally, the first length K is 20mm to 32mm. The first length K can be, but is not limited to, 22mm, 25mm, 28mm, 30mm, 31mm, etc. Specific designs can be tailored to patients of different ages, body types, or conditions, and will not be elaborated upon here.

[0099] The technical features of the embodiments described above can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as the combination of these technical features does not contradict each other, it should be considered within the scope of this specification. The embodiments described above only illustrate several implementation methods of this application, and their descriptions are relatively specific and detailed, but 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 several 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 pump, characterized in that, The blood pump includes: A drive unit for driving blood flow; the drive unit includes a motor and an impeller; and A housing is fitted around the outer periphery of the drive unit, with the proximal end of the housing fixedly connected to the proximal end of the motor; the inner circumferential surface of the housing and the drive unit are radially spaced to form a blood flow channel; the proximal end of the housing is provided with a liquid inlet, and the distal end of the housing is provided with a liquid outlet, which communicates with the liquid inlet through the blood flow channel. The casing includes a first housing and a second housing. The proximal end of the first housing is fixedly connected to the proximal end of the motor, and the distal end of the first housing is connected to the second housing, forming a cylindrical structure to create a straight blood flow channel inside the casing. The first housing has an inlet, and the second housing has an outlet. The motor is located inside the first housing. The impeller is located inside the second housing and connected to the distal end of the motor. The maximum outer diameter of the impeller is greater than the maximum outer diameter of the motor.

2. The blood pump of claim 1, wherein, The first housing includes a first straight tube; the second housing includes a second straight tube coaxially disposed with the first straight tube, the second straight tube being connected to the distal end of the first straight tube, the inner circumferential surface of the second straight tube being flush with the inner circumferential surface of the first straight tube along its axial direction; the outer circumferential surface of the first straight tube being flush with the outer circumferential surface of the first straight tube along its axial direction.

3. The blood pump of claim 2, wherein, The first housing further includes a reducing tube and a plurality of connecting arms connecting the first straight tube and the reducing tube; wherein, the reducing tube is sleeved on the outer periphery of the connection between the blood pump's conduit and the drive unit, and is fixedly connected to at least one of the drive unit and the conduit; the plurality of connecting arms are arranged at intervals along the circumference of the first straight tube, and two adjacent connecting arms form a liquid inlet.

4. The blood pump of claim 3, wherein, The connecting arm has a first connecting portion that connects to the first straight pipe, and a second connecting portion that connects the first connecting portion and the variable diameter pipe; the second connecting portion is located on the outer circumferential surface of the variable diameter pipe, and a notch is formed between two adjacent second connecting portions, the notch being connected to the liquid inlet along the axial direction of the first housing.

5. The blood pump of claim 4, wherein, The second connecting part has a flow guide surface on the side facing the notch, and the distal portion of the flow guide surface extends to the side of the proximal end of the first connecting part. The flow guide surface has a first width in the radial direction of the variable diameter pipe, and the first width first increases and then decreases in the direction from the variable diameter pipe to the first straight pipe.

6. The blood pump of any one of claims 2 to 5, wherein, The second housing also includes a distal end cap connected to the distal end of the second straight tube; the distal end cap is configured as a hollow arch and covers the distal end of the second straight tube; the liquid outlet extends from the side wall of the second straight tube to the distal end cap.

7. The blood pump of claim 6, wherein, The distal end cap includes a top wall and an arched wall arranged circumferentially along the top wall; wherein the top wall is axially opposite and spaced from the distal end of the drive unit for connection to the pig tail tube of the blood pump; the arched wall is disposed at the periphery of the top wall and connected to the second straight tube; the outlet includes a first outlet area located on the second straight tube and a second outlet area located on the arched wall.

8. The blood pump of claim 7, wherein, The outlet has a first orifice wall defining the first outlet area and a second orifice wall defining the second outlet area; the second orifice wall has an inner edge that contacts the inner surface of the arched wall and an outer edge that contacts the outer surface of the arched wall, and the second orifice wall is inclined from its inner edge to its outer edge.

9. The blood pump of claim 8, wherein, The first hole wall has a second width along the radial direction of the second straight pipe, and the second hole wall has a third width along the radial direction of the arched wall, the third width being greater than the second width; And / or, the first hole wall includes a transverse hole wall extending circumferentially along the second straight tube, and arcuate hole walls located at both ends of the transverse hole wall; the second hole wall extends in a semi-circular shape along its length direction, and the two ends of the second hole wall are smoothly connected to the two arcuate hole walls respectively.

10. The blood pump of claim 8, wherein, The second hole wall has a third width radially along the arched wall, and the second hole wall surface includes a central portion adjacent to the top wall, and a first portion and a second portion respectively located on both sides of the central portion; wherein, The third width of the second hole wall located on the first portion gradually increases and then gradually decreases along the direction from the first portion to the middle portion; and / or, the third width of the second hole wall located on the second portion gradually increases and then gradually decreases along the direction from the second portion to the middle portion.

11. The blood pump of claim 6, wherein, The distal end of the impeller extends into the inside of the distal end cover and is radially opposite to the liquid outlet.

12. The blood pump of claim 1, wherein, The second housing further includes a second straight tube and a distal end cap connected to the distal end of the second straight tube; the distal end cap is configured as a hemispherical hollow structure or a semi-elliptical hollow structure and covers the distal end of the second straight tube, and the liquid outlet extends from the side wall of the second straight tube to the distal end cap; or, the second housing includes a second straight tube and a conical top connected to the distal end of the second straight tube; wherein the liquid outlet is provided on the distal side wall of the second straight tube; the conical top includes a hemispherical portion connected to the second straight tube, and a guide cone extending from the hemispherical portion to the distal end of the second straight tube, the diameter of the guide cone being gradually reduced in the direction from the second housing to the first housing.

13. The blood pump of any one of claims 1 to 5, wherein, The proximal end of the motor is connected to the conduit of the blood pump, and the proximal end of the impeller is connected to the shaft of the motor; the maximum outer diameter of the motor is d1, the maximum outer diameter of the impeller is d2, and d1 < d2; the maximum inner diameter of the casing is d3, △D1 = d3 - d1, △D2 = d3 - d2, wherein △D1 is greater than or equal to twice △D2 and less than or equal to four times △D2.

14. The blood pump of any one of claims 1 to 5, characterized in that The housing has a first length in an axial direction of the drive unit; the first length enables the blood pump to pass from the right atrium, the right ventricle, the pulmonary valve to extend into the pulmonary artery, such that the inlet is in the right ventricle and the outlet is in the pulmonary artery.

15. The blood pump of claim 14, wherein, The first length is 25mm-35mm.

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