Blood pump

Abstract

The application relates to a blood pump, which comprises a casing, a driving unit and a cannula assembly; the driving unit is arranged in the casing; the casing and the driving unit are spaced apart by a flow gap; the cannula assembly comprises a compensating tube, which is fixedly connected with the casing and communicates with the flow gap to form a blood flow channel. The casing is provided with a first opening, and the cannula assembly is provided with a second opening. Since the driving unit is arranged in the casing, the axial length of the pump body of the blood pump is shortened. When the blood pump is inserted into the right ventricle, the compensating tube enters the right ventricle first and can deform in the right ventricle, so that the pump body with a relatively short length can also enter the right ventricle, and then the pump body and the compensating tube can deflect in the right ventricle to extend into the pulmonary artery. Since the compensating tube appropriately compensates for the shortened axial length of the pump body, the compensating tube and the pump body can both be clamped by the pulmonary valve, so that the axial length of the blood pump for clamping the pulmonary valve is increased, and the risk of the pump body falling off the pulmonary valve is reduced.

Description

Technical Field

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

[0002] In related technologies, a blood pump capable of intervening in the right ventricle has emerged. This pump passes through the pulmonary valve to enter the pulmonary artery, assisting the right ventricle in pumping blood. To adapt to the right ventricle's delivery path, the pump body is designed with a relatively short axial length. However, this pump body needs to pass through and be held in place by the pulmonary valve, which opens and closes alternately with each heartbeat. Due to the short axial length of the pump body, the pump is easily displaced from the pulmonary valve during its alternating opening and closing.

[0003] The information disclosed above in the background art of this application is only used to understand the background of the concept of this application, and may contain information that does not constitute prior art. Summary of the Invention

[0004] Based on this, this application provides a blood pump that can be used to assist the right ventricle in pumping blood from the right ventricle to the pulmonary artery and reduce the risk of the blood pump dislodging from the pulmonary valve.

[0005] This application provides a blood pump, comprising a housing, a drive unit, and a cannula assembly. The drive unit is disposed inside the housing, 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. A flow gap is formed between the inner circumferential surface of the housing and the drive unit. The cannula assembly includes a compensation tube, which is elastic and fixedly connected to the distal end of the housing to communicate with the flow gap to form a blood flow channel. The proximal end of the housing has a first opening, and the distal end of the cannula assembly has a second opening, which communicates with the first opening through the blood flow channel.

[0006] In one embodiment, the compensation tube is configured as a straight tube extending axially along the drive unit, and the central axes of the compensation tube, the housing, and the drive unit are located on the same straight line.

[0007] In one embodiment, the inner circumferential surface of the compensation tube is flush with the inner circumferential surface of the sleeve along the axial direction of the compensation tube, and the outer circumferential surface of the compensation tube is flush with the outer circumferential surface of the sleeve along the axial direction of the compensation tube.

[0008] And / or, the compensation tube has a first axial length L1, the sleeve has a second axial length L2, and the ratio of the first axial length L1 to the second axial length L2 is 0.7 ≤ L1 / L2 ≤ 1.3.

[0009] In one embodiment, the compensation tube has a first axial length greater than or equal to 20 mm and less than or equal to 35 mm; and / or, the compensation tube includes an inner membrane, an outer membrane, and an elastic coil disposed between the inner membrane and the outer membrane.

[0010] In one embodiment, the housing has a distal port for communication with the compensation tube; the drive unit includes a motor and an impeller connected to the motor, the distal end of the impeller having a distal end furthest from the conduit, the distal end being located within the housing and not extending beyond the distal port, so that the impeller does not extend into the compensation tube.

[0011] In one embodiment, the distal end point and the end face of the distal port are both located on a first plane, which is a plane perpendicular to the axis of the drive unit.

[0012] In one embodiment, the distal end of the casing is provided with a first insertion portion, and the proximal end of the compensation tube is provided with a second insertion portion. The second insertion portion is sleeved on the outer peripheral surface of the first insertion portion, and the overlapping area between the second insertion portion and the first insertion portion has a third axial length of L3. The ratio of the third axial length L3 to the first axial length L1 of the compensation tube is: 1 / 2 ≤ L 3 / L1≤2 / 3.

[0013] In one embodiment, the drive unit includes a motor and an impeller connected to the motor; wherein the maximum outer diameter of the motor is D1, the outer diameter of the impeller is D2, and the inner diameter of the casing is D3, where D3 > D2 > D1.

[0014] In one embodiment, the drive unit includes a motor and an impeller; the drive unit includes a motor and an impeller connected to the motor, the impeller has a hub and blades disposed on the outer circumferential surface of the hub, the diameter of the hub gradually increases along the direction from the motor to the impeller, so that the distance between the outer circumferential surface of the hub and the inner circumferential surface of the casing gradually decreases along the diameter expansion direction of the hub.

[0015] In one embodiment, the motor includes a motor body and a shaft support, the shaft support being connected to the distal end of the motor body for the motor shaft of the motor body to pass through; the distal end of the shaft support is axially opposite to the proximal end of the hub, and the diameter of the shaft support gradually decreases along the direction from the motor to the impeller, such that the shaft support has a first minimum outer diameter D at its distal end. 1min The hub has a second minimum outer diameter D at its proximal end. 4min The second minimum outer diameter D 4min Less than or equal to the first minimum outer diameter D 1min .

[0016] In one embodiment, the housing includes an inlet pipe, a fixing ring, and a connecting pipe, wherein the inlet pipe and the connecting pipe are respectively connected to both ends of the fixing ring; wherein the inlet pipe has the first opening, and the end of the inlet pipe away from the fixing ring is fixedly connected to the proximal end of the drive unit or the conduit; the connecting pipe away from the fixing ring is connected to the compensation pipe; the inner wall surface of the fixing ring is fixedly connected to the outer peripheral surface of the motor of the drive unit through a support member.

[0017] In one embodiment, the inlet pipe includes a straight pipe, a reducing pipe, and a plurality of connecting arms connecting the straight pipe and the reducing pipe; wherein the straight pipe is connected to the fixing ring; 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 circumferentially spaced along the straight pipe, and a first opening is formed between every two adjacent connecting arms.

[0018] In one embodiment, the inner wall surfaces of the straight pipe, the fixing ring, and the connecting pipe are flush with the axial direction of the straight pipe, and the outer wall surfaces of the straight pipe, the fixing ring, and the connecting pipe are also flush with the axial direction of the straight pipe.

[0019] And / or, the connecting arm has a first connecting portion connected to the 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 circumferential surface of the reducing pipe, and a notch is formed between adjacent two second connecting portions, the notch being connected to the first opening along the axial direction of the inlet pipe.

[0020] In one embodiment, the distal end of the blood pump can pass sequentially through the right atrium, right ventricle and pulmonary valve to extend into the pulmonary artery, such that the first opening is located in the right ventricle and the second opening is located in the pulmonary artery.

[0021] In one embodiment, the blood pump includes the catheter having a proximal portion, a distal portion, and a bend. The bend is located between and adjacent to the distal portion. The bend is pre-formed into a bend to adapt its shape to the anatomical structure of a first or second connection point of the right atrium. The first connection point is a connection between the right atrium and the inferior vena cava; the second connection point is a connection between the right atrium and the superior vena cava.

[0022] In the blood pump of this application, a drive unit is disposed inside the housing, and a flow gap is formed between the inner circumferential surface of the housing and the drive unit. The proximal end of the housing is fixed to the proximal end of the drive unit or the conduit of the blood pump, and the distal end of the housing is fixed to the compensation tube of the cannula assembly, so that the compensation tube communicates with the flow gap inside the housing to form a blood flow channel. The proximal end of the housing has a first opening, and the distal end of the cannula assembly has a second opening, which communicates with the first opening through the blood flow channel. The housing and the drive unit constitute the pump body of the blood pump. Because the drive unit is disposed inside the housing, the axial length of the pump body is reduced. When blood enters the right ventricle, the compensation tube enters the right ventricle before the pump body and can undergo elastic deformation within the right ventricle, allowing the shorter pump body to enter the right ventricle after the compensation tube. Furthermore, the pump body and its compensation tube can deflect upwards within the right ventricle to pass through the pulmonary valve and extend into the pulmonary artery. Because the compensating tube appropriately compensates for the shortened axial length of the pump body, both the compensating tube and the pump body can be clamped by the pulmonary valve, thus effectively increasing the axial length of the blood pump that can be clamped and positioned by the pulmonary valve. Therefore, after the blood pump is installed on the pulmonary valve, both the pump body and the compensating tube can be clamped by the pulmonary valve, thereby reducing the risk of the pump body dislodging from the pulmonary valve. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the anatomical structure of the human heart.

[0024] 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.

[0025] Figure 3 for Figure 2 The diagram shows the blood flow during cardiac contraction after the blood pump is implanted in the heart.

[0026] Figure 4 for Figure 2 The diagram shows the blood flow during diastole after the blood pump is implanted in the heart.

[0027] Figure 5This is a schematic diagram of the structure of a blood pump provided in one embodiment of this application.

[0028] Figure 6 for Figure 5 The front view of the blood pump is shown.

[0029] Figure 7 for Figure 6 The blood pump shown is a cross-sectional view along line AA.

[0030] Figure 8 for Figure 7 The diagram shows a comparison of the axial dimensions of the casing and the compensation tube in the blood pump.

[0031] Figure 9 for Figure 7 A magnified view of a portion of the blood pump at point B.

[0032] Figure 10 for Figure 9 The diagram shows a comparison of the radial dimensions of the motor, impeller, and casing in the blood pump.

[0033] Figure 11 for Figure 5 The diagram shows an explosion of a blood pump.

[0034] Figure 12 for Figure 11 The diagram shows a further explosion of the blood pump.

[0035] Figure 13 for Figure 5 The diagram shows an axial view of the compensation tube in the blood pump.

[0036] Figure 14 for Figure 5 The diagram shows an axial view of the connecting tube in the blood pump.

[0037] Figure 15 for Figure 5 A schematic diagram of the outlet tube in the blood pump shown.

[0038] Figure 16 for Figure 5 A schematic diagram of the inlet tube in the blood pump shown.

[0039] Figure 17 for Figure 5 The diagram shows an axial view of the casing and catheter in the blood pump.

[0040] Reference numerals: 10, Blood pump; 11, Pump body; 12, Catheter; 12a, Proximal portion; 12b, Distal portion; 12c, Bend; 100, Shell; 110, Inlet tube; 111, First opening; 112, Straight tube; 113, Reducing tube; 114, Connecting arm; 114a, First connecting part; 114b, Second connecting part; 114c, Guide surface; 115, Notch / groove; 120, Connecting tube; 121, First insertion part; 122, Distal port; 130, Retaining ring; 131, Support; 200, Drive unit; 210, Motor; 211, Shaft support; 212, Motor shaft; 213, Motor body; 220. Impeller; 221, Hub; 222, Blade; 223, Distal end point; 300, Sleeve assembly; 310, Compensation tube; 311, Second insertion part; 312, Fourth insertion part; 320, Outlet tube; 321, Second opening; 322, Third insertion part; 400, Flow gap; 20, Inferior vena cava; 21, Superior vena cava; 22, Right atrium; 23, Tricuspid valve; 24, Right ventricle; 25, Pulmonary valve; 26, Pulmonary artery; 27, Pulmonary vein; 28, Left atrium; 29, Mitral valve; 30, Left ventricle; 31, Aortic valve; 32, Aorta; L1, First axial length; L2, Second axial length; L3, Third axial length. 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] Please see Figure 1 , Figure 1This is an anatomical diagram of the human heart. In related technologies, interventional assistive devices, also known as blood pumps, are mainly used to assist the ventricles in pumping blood by being inserted through a patient's blood vessels into the ventricles. To facilitate understanding of the application of blood pumps, the following is a brief explanation of the heart structure and blood flow direction. Human blood circulation includes systemic circulation and pulmonary circulation. Blood is ejected from the left ventricle 30 through the aortic valve 31 into the aorta 32, where it flows through the aorta 32 to the capillaries throughout the body for substance exchange, transforming arterial blood into venous blood. The venous blood then returns to the right atrium 22 via the superior vena cava 21 and inferior vena cava 20. This circulation is called systemic circulation. Next, blood from the right atrium 22 enters the right ventricle 24 through the tricuspid valve 23, and then is ejected from the right ventricle 24 through the pulmonary valve 25 to the pulmonary artery 26. It then flows through the pulmonary artery 26 to the pulmonary capillaries of various levels for gas exchange, turning venous blood into arterial blood. Finally, the arterial blood flows back from the pulmonary vein 27 to the left atrium 28. Blood from the left atrium 28 enters the left ventricle 30 through the mitral valve 29. This cycle is called the pulmonary circulation.

[0048] A common type of blood pump is the left ventricular assist pump (LVAP). This type of LVAP has a relatively long pump body. When applied to the left ventricle (30), the LVAP is typically positioned from the aorta (32) through the aortic valve (31), with the blood inlet of the LVAP extending into the left ventricle (30), while the blood outlet remains within the aorta (32). In other words, 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 LVAP from the ascending portion of the aorta (32) through the aortic valve (31) into the left ventricle (30) is relatively close to the same axial direction; therefore, this longer pump body allows it to 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 has emerged on the market. This pump has a shorter axial length, allowing it to pass through the pulmonary valve 25 from the right ventricle 24 into the pulmonary artery 26 to assist the right ventricle 24 in pumping blood. However, the pump body of this right ventricular assist pump needs to pass through and be held in place by the pulmonary valve 25. The pulmonary valve 25 opens and closes alternately with the heartbeat. Due to the short axial length of the pump body, it is easily pushed axially by the pulmonary valve 25 during its alternating opening and closing, posing a risk of the pump body dislodging from the pulmonary valve 25.

[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 and reducing the risk of the blood pump dislodging from the pulmonary valve 25. 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 Figure 2 and Figure 5 In one embodiment of the blood pump provided in this application, the blood pump 10 includes a housing 100, a drive unit 200, and a cannula assembly 300; the drive unit 200 is used to drive blood flow, and the drive unit 200 is disposed inside the housing 100. 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, and a flow gap 400 is formed between the inner surface of the housing 100 and the drive unit 200 (e.g., a flow gap 400 is formed between them). Figure 6 and Figure 7 (As shown); the cannula assembly 300 includes a compensation tube 310, which is fixedly connected to the distal end of the housing 100 and communicates with the flow gap 400 to form a blood flow channel. The proximal end of the housing 100 has a first opening 111, and the distal end of the cannula assembly 300 has a second opening 321, which communicates with the first opening 111 through the blood flow channel.

[0053] See Figure 7The first opening 111 and the second opening 321 can each serve as a blood inlet and a blood outlet. When the blood pump 10 is used as a right ventricular assist pump, the first opening 111 serves as a blood inlet and the second opening 321 serves as a blood outlet. After the blood pump 10 is started, the drive unit 200 drives blood F from the first opening 111 into the flow gap 400, then blood F enters the compensation tube 310 from the flow gap 400, and finally exits from the second opening 321 to assist in depressurizing the right ventricle 24, thereby reducing excessive expansion during the congestion of the right ventricle 24. When the blood pump 10 is used as a left ventricular assist pump, the first opening 111 serves as a blood outlet and the second opening 321 serves as a blood inlet. After the blood pump 10 is started, the drive unit 200 drives blood from the second opening 321 into the compensation tube 310, then enters the flow gap 400 from the compensation tube 310, and finally exits from the first opening 111.

[0054] Understandably, in the aforementioned blood pump 10, the housing 100 and the drive unit 200 constitute the pump body 11 of the blood pump 10. Since the drive unit 200 is located inside the housing 100, the axial length of the pump body 11 is reduced. When the blood pump 10 is implanted, the compensation tube 310 of the blood pump 10 enters the right ventricle 24 before the pump body 11. The compensation tube 310 can undergo elastic deformation within the right ventricle 24, allowing the pump body 11, with its shorter axial length, to enter the right ventricle 24 after the compensation tube 310. Furthermore, the pump body 11 and its compensation tube 310 can deflect upwards within the right ventricle 24 to pass through the pulmonary valve 25 and extend into the pulmonary artery 26. Because the compensation tube 310 appropriately compensates for the shortened axial length of the pump body 11, not only the pump body 11 can be clamped by the pulmonary valve 25, but the compensation tube 310 can also be clamped by the pulmonary valve 25. This effectively increases the axial length of the blood pump 10 that can be clamped and positioned by the pulmonary valve 25. Therefore, after the blood pump 10 is installed on the pulmonary valve 25, both the pump body 11 and the compensation tube 310 can be clamped by the pulmonary valve 25, thereby reducing the risk of the pump body 11 falling off the pulmonary valve 25.

[0055] 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.

[0056] 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. Due to the relatively short axial length of the pump body 11 of the blood pump 10, and the elastic deformation of its compensation tube 310, the pump body 11 can pass through each bend of the relatively short delivery path and bend upwards (or deflect) into the pulmonary artery 26 within the narrow right ventricle 24. In the process of the pump body 11 turning upwards from the right ventricle 24 into the pulmonary artery 26, the compensation tube 310 enters the right ventricle 24 before the pump body 11. Through elastic deformation within the right ventricle 24, the compensation tube 310 not only allows the pump body 11 to subsequently enter the right ventricle 24, but also allows it to bend (or deflect) upwards from the right ventricle 24 to partially extend into the pulmonary artery 26. This ensures that the first opening 111 of the blood pump 10 is located within the right ventricle 24, while the second opening 321 of the blood pump 10 is located within the pulmonary artery 26. This significantly reduces the difficulty of the blood pump 10 entering the right ventricle 24 and improves the smoothness of the blood pump 10's passage through the delivery path.

[0057] It's easy to understand that the heart is always undergoing contraction and expansion. For example... Figure 3 As shown, during cardiac contraction, the pulmonary artery 26 opens, allowing blood to flow from the right ventricle 24 into the pulmonary artery 26. At this time, the clamping force of the pulmonary valve 25 on the blood pump 10 decreases. Therefore, under the impact of the blood flow along the Q1 direction, the pump body 11 of the blood pump 10 tends to move towards the pulmonary artery 26. Similarly, as... Figure 4 As shown, the pulmonary valve 25 closes when the heart expands, and the pulmonary valve 25 has a tendency to move the pump body 11 carrying the blood pump 10 into the right ventricle 24 along the Q2 direction.

[0058] Therefore, the blood pump 10 of this application, by placing the drive unit 200 inside the housing 100, shortens the axial length of the pump body 11 to approximately equal to the axial length of the housing 100. Thus, when the compensation tube 310 of the blood pump 10 enters the right ventricle 24, the compensation tube 310 only needs to undergo a small elastic deformation to allow the shorter pump body 11 to also enter the right ventricle 24. Because the axial length of the pump body 11 is short and the compensation tube 310 can undergo elastic deformation, the pump body 11 of the blood pump 10 can deflect upwards in the right ventricle, passing through the pulmonary valve 25 and extending into the pulmonary artery 26. This allows the first opening 111 to be located within the right ventricle 24, while the second opening 321 of the blood pump 10 is located within the pulmonary artery 26. Furthermore, the compensation tube 310 and the pump body 11 are arranged axially, so not only the pump body 11 can be clamped by the pulmonary valve 25, but the compensation tube 310 can also be clamped by the pulmonary valve 25. This effectively increases the axial length of the blood pump 10 that can be used for clamping and positioning the pulmonary valve. Therefore, after the blood pump 10 passes through the pulmonary valve 25, during the alternating opening and closing of the pulmonary valve 25 with the heartbeat, the pulmonary valve 25 can be clamped on at least one of the pump body 11 and the compensation tube 310, thereby reducing the risk of the blood pump 10 dislodging from the pulmonary valve 25.

[0059] In one embodiment, both the first opening 111 and the second opening 321 of the blood pump 10 can connect to the blood flow channel. That is, either the first opening 111 or the second opening 321 can serve as a blood inlet, while the other serves as a blood outlet. This application does not limit which one serves as the blood inlet, but for ease of understanding and explanation, the following embodiments will use the first opening 111 as the blood inlet and the second opening 321 as the blood outlet as an example to illustrate the specific implementation of the blood pump 10 provided in this application. It should be understood that the reverse is also true, so it will not be repeated here.

[0060] Please see Figure 2 In one embodiment, the blood pump 10 can pass through the inferior vena cava 20, right atrium 22, right ventricle 24, and pulmonary valve 25 to extend into the pulmonary artery 26, such that the first opening 111 is located within the right ventricle 24, and the second opening 321 is located within the pulmonary artery 26. Thus, when the blood pump 10 is operating, it can directly pump blood into the pulmonary artery 26, reducing the possibility of excessive blood accumulation in the right ventricle 24 leading to over-dilation of the right ventricle 24. This improves the safety of using the blood pump 10. Furthermore, since the first opening 111 is located within the right ventricle 24, when the blood pump 10 is operating, it can also guide blood from the superior vena cava 21 and inferior vena cava 20 through the right atrium 22 into the right ventricle 24 to assist in cardiac blood delivery. See [link to blood flow path and direction within the blood pump 10] for details. Figure 7 and Figure 8 The standard number is Q.

[0061] Please see Figures 6 to 8 For conventional left ventricular assist pumps (LVAPs), a flexible sleeve is typically connected to the distal end of the pump body 11. Only a portion of this sleeve extends into the left ventricle. Therefore, to accommodate the left ventricular delivery path, the length of this sleeve is often several times the length of the pump body 11, and it is typically pre-shaped into a bent form, allowing for elastic deformation in its bending direction. In one embodiment of this application, a compensation tube 310 is used to appropriately compensate for the shortened length of the pump body 11 after the drive unit 200 is housed inside the housing 100. Therefore, the axial length of the compensation tube 310 is designed to be shorter to ensure that after the compensation tube 310 as a whole can enter the right ventricle 24, the pump body 11 of the blood pump 10 can also enter the right ventricle 24. Optionally, the compensation tube 310 has a first axial length L1, which is greater than or equal to 20 mm and less than or equal to 35 mm, i.e., 20 mm ≤ L1 ≤ 35 mm. For example, the value of the first axial length L1 can be, but is not limited to, 22mm, 25mm, 28mm, 30mm, 34mm, etc.

[0062] Furthermore, since the axial length of the compensation tube 310 is relatively short, and no significant directional bending is required during implantation into the right ventricle, in this embodiment, the compensation tube 310 is configured as a straight tube extending axially along the drive unit 200. This configuration eliminates the need for bending and shaping processes, reducing manufacturing difficulty and improving production efficiency. Because the compensation tube 310 is a straight tube, it has a linear central axis M1M2. Optionally, the central axes of the compensation tube 310, the housing 100, and the drive unit 200 are located on the same straight line. The compensation tube 310, the housing 100, and the drive unit 200 share the same central axis M1M2. This allows the blood flow channel, formed by the flow gap 400 and the compensation tube 310, to extend linearly along the axial direction, resulting in less resistance to blood flow and allowing blood to pass through more smoothly.

[0063] Please see Figure 8 In one embodiment, the outer peripheral surface of the compensation tube 310 and the outer peripheral surface of the housing 100 are configured to be flush along the axial direction of the compensation tube 310, so that the overall shape of the blood pump 10 is smooth and regular, thereby improving the smoothness of the blood pump 10 implantation process and reducing the obstruction of the external blood flow of the blood pump 10, while also reducing the probability of blood stasis forming on the surface of the blood pump 10.

[0064] Please see Figure 8In one embodiment, since the inner circumferential surface of the compensation tube 310 and the inner circumferential surface of the housing 100 both form the sidewall of the blood flow channel, the inner circumferential surface of the compensation tube 310 and the inner circumferential surface of the housing 100 are set to be flush with the axial direction of the compensation tube 310 to avoid forming a diameter-changing step at the connection between the compensation tube 310 and the housing 100. This makes the sidewall of the blood flow channel smoother along the axial direction, thereby reducing the resistance of the blood flow channel to blood flow, allowing blood to pass through the blood flow channel more smoothly, and improving the pumping efficiency of the blood pump 10.

[0065] Please also see Figure 8 In one embodiment, the compensation tube 310 has a first axial length L1, and the housing 100 has a second axial length L2. The ratio of the first axial length L1 to the second axial length L2 is 0.7 ≤ L1 / L2 ≤ 1.3, that is, 0.7L2 ≤ L1 ≤ 1.3L2. Since the housing 100 and the drive unit 200 constitute the rigid part of the pump body 11 of the blood pump 10, and the compensation tube 310 constitutes the elastic part of the pump body 11, and the axial length of the rigid part of the pump body 11 is approximately equal to the length of the housing 100, limiting the ratio of the first axial length L1 of the compensation tube 310 to the second axial length L2 of the housing 100 to 0.7 ≤ L1 / L2 ≤ 1.3 is equivalent to limiting the size ratio of the elastic part to the rigid part of the pump body 11 to 0.7 ≤ L1 / L2 ≤ 1.3. This avoids the compensating tube 310 being too long, reducing the difficulty of the pump body 11 entering the right ventricle; and the size of the rigid part of the pump body 11 will not be too short, ensuring that the axial length of the drive unit 200 of the pump body 11 is not too shortened, so that the drive unit 200 has sufficient driving force.

[0066] In one embodiment, the compensation tube 310 can be configured as a multi-layered composite structure to balance flexibility, support, and toughness. For example, the compensation tube 310 includes an inner membrane, an outer membrane, and an elastic coil disposed between the inner and outer membranes, forming a compensation tube 310 that balances elastic deformation and connection support. It is easily understood that the inner membrane is attached to the inner surface of the elastic coil to form an inner peripheral wall for blood flow, and the outer membrane is attached to the outer surface of the elastic coil to form the outer peripheral wall of the compensation tube 310. Of course, the compensation tube 310 is not limited to a three-layer structure; the number of layers and the materials used for each layer can be adaptively adjusted according to actual needs. For example, a braided layer can be added inside the compensation tube 310 to improve toughness.

[0067] In one embodiment, the housing 100 is a non-elastic structure. Optionally, the housing 100 is made of a rigid material. This allows the housing 100 to have high rigidity, thereby enabling the formation of a structurally stable flow gap 400 between the housing 100 and the drive unit 200 for stable blood delivery. For example, the rigid material can be a metal or a polymer.

[0068] Please see Figures 7 to 9 In one embodiment, the drive unit 200 includes a motor 210 and an impeller 220 connected to the motor 210. Both the motor 210 and the impeller 220 are housed within the housing 100. The motor 210 can drive the impeller 220 to rotate, thereby driving blood flow. Considering that the first axial length L1 of the compensation tube 310 is relatively short, when the blood pump 10 pushes along the right ventricular path sequentially from the right atrium to the right ventricle, through the pulmonary valve, and into the pulmonary artery, the relatively narrow pushing path may cause the blood pump 10 to bend at the proximal end of the compensation tube 310. If the impeller 220 extends from the inside of the housing 100 to the inside of the compensation tube 310, when the proximal end of the compensation tube 310 bends and deforms, the inner circumferential surface of the compensation tube 310 will contact or abut against the impeller 220, thereby interfering with the impeller 220 and hindering its rotation.

[0069] Optionally, the housing 100 has a distal port 122 for communication with the compensation tube 310; the distal end of the impeller 220 has a distal end point 223 furthest from the motor 210, which is located within the housing 100 and does not extend beyond the distal port 122, so that the impeller 220 does not extend into the compensation tube 310. Specifically, because the housing 100 has a relatively rigid structure, it can provide a spatially stable internal cavity so that the impeller 220 can rotate stably. When the blood pump 10 passes through the pulmonary artery along the right ventricular push path, even if the blood pump 10 bends at the proximal end of the compensation tube 310, since the impeller 220 does not extend into the compensation tube 310, the inner circumferential surface of the compensation tube 310 will not contact the impeller 220, and thus will not hinder the rotation of the impeller 220.

[0070] Please see Figure 10 and Figure 11 In one embodiment, the distal end 223 of the impeller 220 and the distal port 122 are both located on a first plane PL, which is perpendicular to the axis of the drive unit. That is, the distal end of the impeller 220 extends to the distal port 122 of the housing 100 to fully utilize the axial space of the housing 100 to arrange a longer impeller 220, thereby increasing the size of the impeller 220 and enabling it to drive more blood flow, increasing the pumped blood flow rate. Of course, in other embodiments, the distal end 223 of the impeller 220 may also be axially spaced from the distal port 122PL.

[0071] Please see Figure 10 , Figure 12 and Figure 13In one embodiment, the distal end of the housing 100 is provided with a first insertion portion 121, and the proximal end of the compensation tube 310 is provided with a second insertion portion 311. The second insertion portion 311 is sleeved on the outer peripheral surface of the first insertion portion 121 and is bonded and fixed to the outer peripheral surface of the first insertion portion 121. Figure 8 Optionally, the overlapping area of ​​the first insertion part 121 and the second insertion part 311 has a third axial length L3, wherein the ratio of the third axial length L3 to the first axial length L1 of the compensation tube 310 is: 0.1 ≤ L 3 / L1≤0.3, that is, 0.1L1≤L3≤0.3L1. The value of L3 can be, but is not limited to, 0.12L1, 0.15L1, 0.2L1, 0.25L1, and 0.3L1.

[0072] Specifically, because the compensating tube 310 is relatively short, when it bends, its proximal end experiences a significant bending force, and the connection between the second insertion part 311 and the first insertion part 121 bears a large bending force. The ratio of the third axial length L3 of the overlapping area of ​​the first insertion part 121 and the second insertion part 311 to the first axial length L1 of the compensating tube 310 is defined as 0.1 ≤ L. 3 / A length L1 ≤ 0.3 allows the second insertion part 311 to have a larger area for engaging with the first insertion part 121, resulting in a more secure connection between them. Thus, even when the compensation tube 310 is bent and deformed, the connection between the second insertion part 311 and the first insertion part 121 will not easily loosen or detach, effectively improving the safety performance of the blood pump 10. In other words, by appropriately setting the third axial length L3, the stability of the connection between the housing 100 and the compensation tube 310 is improved.

[0073] Please see Figure 10 In traditional blood pumps, the motor is typically directly connected to the casing assembly, with only the impeller located inside the casing assembly. Since the outer diameter of the motor is usually the same as the outer diameter of the casing assembly, the impeller diameter is typically smaller than the motor diameter. However, in this application, the drive unit 200 of the blood pump 10 is located inside the casing 100, meaning both the motor 210 and the impeller 220 are located inside the casing 100. Assuming the diameter of the motor 210 is D1, the diameter of the impeller 220 is D2, and the inner diameter of the casing 100 is D3, then we should have: D3 > D1, and D3 > D2.

[0074] Therefore, the impeller 220 can be designed to be larger by making full use of the internal space of the housing 100. Optionally, the relationship between the diameter D1 of the motor 210, the diameter D2 of the impeller 220, and the inner diameter D3 of the housing 100 is D3 > D2 > D1. That is, compared to conventional blood pumps, the diameter of the impeller 220 of the blood pump 10 of this application can be designed to be larger than the diameter of the motor 210, allowing the impeller 220 to have a larger radial dimension than the motor 210, thereby increasing the output power of the impeller 220 and improving the overall pumping efficiency of the blood pump 10. It can be understood that the diameter D1 of the motor 210 is the maximum radial dimension of the motor 2210, and the diameter D2 of the impeller 220 is also the maximum radial dimension of the impeller 220; the inner diameter D3 of the housing 100 is the diameter of the area within the housing 100 that houses the motor 210 and the impeller 220.

[0075] Please see Figure 9 and Figure 10 In one embodiment, the impeller 220 has a hub 221 and blades 222, with the blades 222 disposed on the outer periphery of the hub 221. The hub 221 and the shaft support 211 are axially opposite each other. Since the impeller 220 is an axial-flow impeller, the blood driven by the impeller 220 possesses not only axial kinetic energy but also a portion of radial kinetic energy. This axial kinetic energy enables the blood to flow rapidly along the axial direction of the compensation tube 310 through its inner cavity.

[0076] Therefore, in order to enable blood to gain greater axial kinetic energy after passing through the impeller 220, in this embodiment, the diameter of the hub 221 is set to gradually increase along the direction from the motor 210 to the impeller 220, so that the distance between the outer peripheral surface of the hub 221 and the inner peripheral surface of the casing 100 gradually decreases along the diameter expansion direction of the hub 221. The diameter expansion direction is along the direction from the motor 210 to the impeller 220. This setting allows the distal diameter of the hub 221 to be larger, so that the distance K2 between the distal outer peripheral surface of the hub 221 and the inner peripheral surface of the casing 100 is smaller than the distance K1 between the proximal outer peripheral surface of the hub 221 and the inner peripheral surface of the casing 100, i.e., K2 < K1. Blood F3 enters the impeller 220 from the gap K1 and is driven by the impeller 220 to rotate spirally, thus being gradually propelled towards the gap K2 by the impeller 220. As the path from the gap K1 to the gap K2 gradually narrows, the blood F3 is gradually compressed by the spiral during this process, causing a portion of the radial potential energy gained by the blood F3 due to being driven spirally by the impeller 220 to be converted into axial potential energy, thereby increasing the axial potential energy of the blood F3. This, in turn, increases the axial velocity component of the blood F3, allowing the blood F3 to flow rapidly through the inner cavity of the compensation tube 310 along the axial direction.

[0077] Please also see Figure 9 and Figure 10 In one embodiment, the motor 210 includes a motor body 213 and a shaft support 211, the shaft support 211 being connected to the distal end of the motor body 213; the motor shaft 212 of the motor 210 passes through the shaft support 211 from the motor body 213 and is fixedly connected to the impeller 220. Optionally, the distal end of the shaft support 211 is axially opposite to the proximal end of the hub 221; and the diameter of the shaft support 211 gradually decreases along the direction from the motor 210 to the impeller 220. This allows blood around the shaft support 211 to be guided by the outer peripheral surface of the shaft support 211 to flow along its narrowing direction, thereby being guided by the shaft support 211 into the impeller 220, increasing the blood flow driven by the impeller 220.

[0078] Furthermore, the shaft support 211 has a first minimum outer diameter D at its distal end. 1min The hub 221 has a second minimum outer diameter D at its proximal end. 4min The second minimum outer diameter D 4min Less than or equal to the first minimum outer diameter D 1min D 4min ≤D 1min It is easy to understand that the proximal end of the hub 221 is at its minimum radial dimension, and the distal end of the shaft support 211 is at its minimum radial dimension. The proximal end of the hub 221 and the distal end of the shaft support 211 are opposite and adjacent to each other along the axial direction of the impeller 220. This is because the second minimum outer diameter D... 4min Less than or equal to the first minimum outer diameter D 1min When blood is guided by the outer peripheral surface of the shaft support 211 to flow towards the impeller 220 along its narrowing direction, the blood that has separated from the distal outer peripheral surface of the shaft support 211 can flow to the outer peripheral surface of the hub 221 of the impeller 220, thus avoiding collision between this part of the blood and the proximal end face of the hub 221 and reducing the loss of blood kinetic energy.

[0079] In other words, because the radial dimension of the shaft support 211 is greater than or equal to that of the hub 221 in the region where the shaft support 211 and the hub 221 are close to each other, the shaft support 211 can guide blood smoothly across the transition connection between the shaft support 211 and the hub 221. This improves blood flow smoothness, resulting in higher pumping efficiency for the blood pump 10. Furthermore, it reduces the likelihood of blood clots forming at the transition connection between the shaft support 211 and the hub 221.

[0080] Please see Figure 9 and Figure 12In one embodiment, the housing 100 includes an inlet pipe 110, a fixing ring 130, and a connecting pipe 120; the inlet pipe 110 and the connecting pipe 120 are respectively connected to both ends of the fixing ring 130. The inlet pipe 110 has a first opening 111. The end of the inlet pipe 110 furthest from the fixing ring 130 (i.e., the proximal end of the inlet pipe 110) is fixedly connected to the proximal end of the drive unit 200 or the conduit 12; the end of the connecting pipe 120 furthest from the fixing ring 130 (i.e., the distal end of the connecting pipe 120) is connected to the compensation pipe 310; the inner wall surface of the fixing ring 130 is fixedly connected to the outer peripheral surface of the motor 210 via a support member 131.

[0081] Specifically, the retaining ring 130 is fitted around the outer periphery of the motor 210, and the inner wall surface of the retaining ring 130 is spaced apart from the outer periphery surface of the motor 210. Multiple support members 131 are provided on the inner wall surface of the retaining ring 130, and these support members 131 are fixedly connected to the outer periphery surface of the motor 210 to support and fix the retaining ring 130. The retaining ring 130 forms the sidewall of the middle portion of the housing 100. Therefore, the retaining ring 130 is stably supported by the support members 131, allowing it to play a central supporting role on the housing 100. This ensures that both the inlet pipe 110 and the connecting pipe 120 have a stable relative position with respect to the outer surface of the motor 210, thereby improving the stability of the blood flow channel structure formed between the housing 100 and the drive unit 200.

[0082] It is worth mentioning that the shape and structure of the aforementioned support member 131 are not specifically limited. The support member 131 can be a support rib extending radially along the motor 210, or it can be a guide plate extending axially along the motor 210. During assembly, the inlet pipe 110 of the housing 100 can be looped from the proximal end of the motor 210 to the outer periphery of the proximal end of the motor 210 and fixed to the proximal end of the fixing ring 130; and the connecting pipe 120 of the housing 100 can be looped from the distal end of the motor 210 to the outer periphery of the distal end of the motor 210 and fixed to the distal end of the fixing ring 130. In this way, the housing 100 and the motor 210 are connected and fixed, which improves the convenience of assembly.

[0083] Please refer to 11 to Figure 14 Optionally, the first insertion part 121 is provided at the far end of the connecting pipe 120, and the connecting pipe 120 is inserted and engaged with the second insertion part 311 of the compensation pipe 310 through the first insertion part 121.

[0084] Please see Figure 12 , Figure 16 and Figure 17In one embodiment, the inlet pipe 110 includes a straight pipe 112, a reducing pipe 113, and a plurality of connecting arms 114 connecting the straight pipe 112 and the reducing pipe 113. The straight pipe 112 is connected to a fixing ring 130; the reducing pipe 113 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 drive unit 200 and the conduit 12. The plurality of connecting arms 114 are arranged at intervals along the circumferential direction of the straight pipe 112, and a first opening 111 is formed between every two adjacent connecting arms 114.

[0085] Specifically, the straight tube 112 is arranged in a straight tube shape so that its inner circumferential surface forms a cylindrical surface, reducing fluid resistance in the blood flow channel. The reducing tube 113 is arranged in a conical shape. By fitting the reducing tube 113 around the outer circumference of the connection between the catheter 12 and the drive unit 200, the connection can be wrapped inside the reducing tube 113, preventing the adhesive at the connection from being washed away by blood. The reducing tube 113 has two interfaces, one of which is press-fitted with the distal outer circumferential surface of the catheter 12, and the other interface is press-fitted with the proximal outer circumferential surface of the drive unit 200. The straight tube 112, the reducing tube 113, and the connecting arm 114 can be integrally formed.

[0086] Furthermore, the inner walls of the straight tube 112, the fixing ring 130, and the connecting tube 120 are flush axially to facilitate smooth blood flow. Additionally, the outer walls of the straight tube 112, the fixing ring 130, and the connecting tube 120 are also flush axially. This arrangement forms a regular cylinder. This design, on the one hand, ensures a smooth and regular outer surface of the casing 100, reducing damage to human tissues during the implantation of the blood pump 10; on the other hand, the relatively smooth and regular inner surface of the casing 100 reduces resistance to fluid flow, minimizes kinetic energy loss during blood flow, improves pumping efficiency, and reduces damage to blood cells.

[0087] Please see Figure 17 In one embodiment, the connecting arm 114 includes a first connecting portion 114a connected to the straight pipe 112, and a second connecting portion 114b connecting the first connecting portion 114a and the reducing pipe 113; wherein the connecting arm 114 is located on the outer peripheral surface of the reducing pipe 113, and a notch 115 is formed between two adjacent second connecting portions 114b, and the notch 115 is connected to the proximal end of the first opening 111 along the axial direction of the inlet pipe 110.

[0088] When the drive unit 200 generates suction, a portion of blood F2 is drawn radially from the circumference of the inlet pipe 110 into the first opening 111, and then continues to be driven by the drive unit 200 to switch to axial flow into the flow gap 400. Another portion of blood F1 enters axially from the notch 115 into the inner side of the first opening 111, pushing the portion of blood F2 entering from the first opening 111 to flow axially, thereby accelerating the flow of blood F2 into the flow gap 400. This effectively increases the blood flow rate entering from the first opening 111, improving the pumping efficiency of the blood pump 10. In other words, by setting the second connecting part 114b to cooperate with the reducing pipe 113 to form the notch 115, the smoothness of blood entering the first opening 111 can be improved, reducing the probability of blood congestion at the first opening 111.

[0089] Furthermore, a guide surface 114c is provided on the side of the second connecting portion 114b facing the notch groove 115. The guide surface 1242 is used to guide blood from the notch groove 115 axially into the inner side of the first opening 111, accelerating blood flow and improving pumping efficiency. The guide surface 1242 is generally prismatic, and the distal portion of the guide surface 1242 extends to the proximal side of the first connecting portion 1231.

[0090] Please see Figure 12 and Figure 15 In one embodiment, the cannula assembly 300 further includes an outlet tube 320, which is fixedly connected to the end of the compensation tube 310 away from the housing 100. The outlet tube 320 has a second opening 321. A third insertion portion 322 is provided at the proximal end of the outlet tube 320, and a fourth insertion portion 312 is provided at the distal end of the compensation tube 310. The third insertion portion 322 and the fourth insertion portion 312 are inserted and engaged to connect the compensation tube 310 and the outlet tube 320. The inner peripheral wall of the outlet tube 320 is axially flush with the inner peripheral wall of the compensation tube 310 to facilitate smooth blood flow; the outer peripheral wall of the outlet tube 320 is axially flush with the outer peripheral wall of the compensation tube 310 to make the overall shape of the blood pump 10 smooth and regular, facilitating the movement of the blood pump 10 in blood vessels or the heart.

[0091] Please see Figure 7 and Figure 8 In one embodiment, the blood pump 10 includes a catheter 12 that extends from the outside into the proximal end of the housing 100 to connect with the drive unit 200. The proximal end of the housing 100 can be fitted onto the catheter 12, the drive unit 200, or the connection point between the catheter 12 and the drive unit 200, to connect directly or indirectly to the drive unit 200. The pump body portion described in the embodiments of this application refers to the housing 100, the drive unit 200, and the cannula assembly 300 collectively, that is, the portion of the blood pump 10 excluding the catheter 12.

[0092] Please see Figure 3 In one embodiment, the catheter 12 has a proximal portion 12a, a distal portion 12b, and a bend 12c. The bend 12c is located between and adjacent to the distal portion 12b. The bend 12c is pre-formed into a bend shape to adapt its shape to the anatomical structure of the first connection point of the right atrium 22. The first connection point refers to the connection between the inferior vena cava 20 and the right atrium 22. Thus, the bend 12c of the catheter 12 can adapt to the shape of the connection point between the inferior vena cava 20 and the right atrium 22, allowing the blood pump 10 to enter the right atrium 22 from the inferior vena cava 20 through the first connection point. This reduces the difficulty for the blood pump 10 to pass through the bend of the first connection point, improves the smoothness of the blood pump 10's delivery, and reduces the damage and discomfort caused by the blood pump 10 to the human body.

[0093] Of course, in another embodiment, the shape of the bend 12c is adapted to the anatomical shape of the second connecting point of the right atrium 22. The second connecting point refers to the connection between the superior vena cava 21 and the right atrium 22. Thus, the bend 12c of the catheter 12 can adapt to the shape of the connecting point between the superior vena cava 21 and the right atrium 22, allowing the blood pump 10 to enter the right atrium 22 from the superior vena cava 21 through the second connecting point, reducing the difficulty for the blood pump 10 to pass through the bend of the second connecting point, improving the smoothness of the blood pump 10's delivery, and reducing the damage and discomfort caused by the blood pump 10 to the human body.

[0094] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0095] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A blood pump, characterized in that, The blood pump includes: Shell; A drive unit, disposed inside the housing, includes a motor and an impeller connected to the motor, both of which are housed within the housing; the proximal end of the housing is fixedly connected to the proximal end of the drive unit or a conduit of the blood pump; a flow clearance is formed between the inner circumferential surface of the housing and the drive unit; and A cannula assembly, the cannula assembly including a compensating tube, the compensating tube being elastic, the compensating tube being fixedly connected to the distal end of the cannula to communicate with the flow gap to form a blood flow channel; The proximal end of the sheath has a first opening, and the distal end of the cannula assembly has a second opening, the second opening being connected to the first opening via the blood flow channel. The casing is a non-elastic structure. The maximum outer diameter of the motor is D1, the outer diameter of the impeller is D2, and the inner diameter of the casing is D3, where D3 > D2 > D1. The casing includes an inlet pipe, a fixing ring, and a connecting pipe. The inlet pipe and the connecting pipe are respectively connected to the two ends of the fixing ring. The inlet pipe includes a straight pipe, and the inner wall surfaces of the straight pipe, the fixing ring, and the connecting pipe are flush along the axial direction of the straight pipe.

2. The blood pump according to claim 1, characterized in that, The compensation tube is configured as a straight tube extending along the axial direction of the drive unit, and the central axes of the compensation tube, the housing, and the drive unit are located on the same straight line.

3. The blood pump according to claim 2, characterized in that, The inner circumferential surface of the compensation tube is flush with the inner circumferential surface of the sleeve along the axial direction of the compensation tube, and the outer circumferential surface of the compensation tube is flush with the outer circumferential surface of the sleeve along the axial direction of the compensation tube. And / or, the compensation tube has a first axial length L1, the sleeve has a second axial length L2, and the ratio of the first axial length L1 to the second axial length L2 is 0.7 ≤ L1 / L2 ≤ 1.

3.

4. The blood pump according to claim 1, characterized in that, The compensation tube has a first axial length, which is greater than or equal to 20 mm and less than or equal to 35 mm; and / or, the compensation tube includes an inner membrane, an outer membrane, and an elastic coil disposed between the inner membrane and the outer membrane.

5. The blood pump according to any one of claims 1 to 4, characterized in that, The casing has a distal port for communication with the compensation pipe; the distal end of the impeller has a distal end furthest from the conduit, the distal end being located inside the casing and not extending beyond the distal port, so that the impeller does not extend into the compensation pipe.

6. The blood pump according to claim 5, characterized in that, The distal end point and the end face of the distal port are both located on a first plane, which is a plane perpendicular to the axis of the drive unit.

7. The blood pump according to claim 5, characterized in that, The distal end of the casing is provided with a first insertion portion, and the proximal end of the compensation tube is provided with a second insertion portion. The second insertion portion is sleeved on the outer peripheral surface of the first insertion portion. The overlapping area between the second insertion portion and the first insertion portion has a third axial length of L3. The ratio of the third axial length L3 to the first axial length L1 of the compensation tube is: 1 / 2 ≤ L 3 / L1≤2 / 3.

8. The blood pump according to claim 5, characterized in that, The distal end of the impeller and the distal end of the pipe are spaced apart axially.

9. The blood pump according to any one of claims 1 to 4, characterized in that, The impeller has a hub and blades disposed on the outer circumferential surface of the hub. The diameter of the hub gradually increases along the direction from the motor to the impeller, so that the distance between the outer circumferential surface of the hub and the inner circumferential surface of the casing gradually decreases along the diameter expansion direction of the hub.

10. The blood pump according to claim 9, characterized in that, The motor includes a motor body and a shaft support. The shaft support is connected to the distal end of the motor body for the motor shaft of the motor body to pass through. The distal end of the shaft support is axially opposite to the proximal end of the hub. The diameter of the shaft support gradually decreases along the direction from the motor to the impeller, such that the shaft support has a first minimum outer diameter D at its distal end. 1min The hub has a second minimum outer diameter D at its proximal end. 4min The second minimum outer diameter D 4min Less than or equal to the first minimum outer diameter D 1min .

11. The blood pump according to any one of claims 1 to 4, characterized in that, The inlet pipe has the first opening, and the end of the inlet pipe away from the fixed ring is fixedly connected to the proximal end of the drive unit or the conduit; the connecting pipe away from the fixed ring is connected to the compensation pipe; the inner wall surface of the fixed ring is fixedly connected to the outer peripheral surface of the motor of the drive unit through a support member.

12. The blood pump according to claim 11, characterized in that, The inlet pipe includes a reducing pipe and a plurality of connecting arms connecting the straight pipe and the reducing pipe; wherein the straight pipe is connected to the fixing ring; 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 straight pipe, and a first opening is formed between each two adjacent connecting arms.

13. The blood pump according to claim 12, characterized in that, The outer walls of the straight pipe, the fixing ring, and the connecting pipe are also flush with the axial direction of the straight pipe. And / or, the connecting arm has a first connecting portion connected to the 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 circumferential surface of the reducing pipe, and a notch is formed between adjacent two second connecting portions, the notch being connected to the first opening along the axial direction of the inlet pipe.

14. The blood pump according to any one of claims 1 to 4, characterized in that, The distal end of the blood pump can pass sequentially through the right atrium, right ventricle and pulmonary valve to extend into the pulmonary artery, such that the first opening is located in the right ventricle and the second opening is located in the pulmonary artery.

15. The blood pump according to claim 14, characterized in that, The blood pump includes the catheter, which has a proximal portion, a distal portion, and a bend. The bend is located between the proximal portion and the distal portion and is adjacent to the distal portion. The bend is pre-formed into a bend shape to adapt the shape of the bend to the anatomical structure of the first or second connection point of the right atrium. The first connection point is the connection between the right atrium and the inferior vena cava; the second connection point is the connection between the right atrium and the superior vena cava.

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