Blood pump

Abstract

A blood pump (10), comprising a sleeve housing (100), a driving unit (200), and a sleeve assembly (300). The driving unit (200) is arranged in the sleeve housing (100). The sleeve housing (100) and the driving unit (200) are spaced by a flow gap (500). The sleeve assembly (300) comprises a compensation tube (310), the compensation tube (310) being fixedly connected to the sleeve housing (100) and being in communication with the flow gap (500) to form a blood flow channel. A proximal end of the sleeve housing (100) is provided with a first opening (111), and a distal end of the sleeve assembly is provided with a second opening (321).

Description

blood pump

[0001] This application claims priority to two Chinese patent applications with application number CN202311447400.2 and name “Blood Pump” and application number CN202311432166.6 and name “Blood Pump” filed with the China Patent Office on October 31, 2023, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the technical field of medical devices, and in particular to a blood pump. Background Art

[0003] In the related art, there is a blood pump that can intervene in the right ventricle. This blood pump can pass through the pulmonary valve from the right ventricle to enter the pulmonary artery to assist the right ventricle in pumping blood. In order to adapt to the push path of the right ventricle, the axial length of the pump body of this blood pump is designed to be shorter. However, the pump body of this blood pump needs to pass through the pulmonary valve and be clamped and positioned by the pulmonary valve. The pulmonary valve will alternately open and close with the beating of the heart. Since the axial length of the pump body of this blood pump is too short, the blood pump is easily pushed axially by the pulmonary valve during the process of alternating opening and closing of the pulmonary valve, which makes the blood pump at risk of loosening from the pulmonary valve.

[0004] BACKGROUND OF THE INVENTION The above information disclosed is only for understanding the background of the concept of the application and may contain information that does not constitute the prior art.

[0005] Summary of the Invention

[0006] Based on this, the present application provides a blood pump, which 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 being loosened from the pulmonary valve.

[0007] The present application provides a blood pump, comprising a housing, a drive unit, and a cannula assembly; the drive unit is disposed within the housing, the proximal end of the housing being fixedly connected to the proximal end of the drive unit or a catheter of the blood pump; an overflow gap is formed between the inner circumferential surface of the housing and the drive unit; the cannula assembly includes a compensating tube, the compensating tube being elastic and fixedly connected to the distal end of the housing to communicate with the overflow gap to form a blood flow channel. The proximal end of the housing is provided with a first opening, and the distal end of the cannula assembly is provided with a second opening, the second opening being connected to the first opening through the blood flow channel.

[0008] The present application also provides a blood pump, comprising:

[0009] A casing, wherein the casing is provided with a liquid inlet and a liquid outlet;

[0010] A drive unit is disposed within the housing, with a proximal end of the housing fixedly connected to a proximal end of the drive unit or a catheter of the blood pump; a blood flow channel is formed between the inner circumferential surface of the housing and the drive unit, and the blood flow channel connects the liquid inlet and the liquid outlet; wherein the drive unit includes a motor and an impeller connected to the motor;

[0011] a cannula assembly, the cannula assembly being provided with a liquid discharge port, the cannula assembly including a compensating tube, the compensating tube being elastic and fixedly connected to and in communication with the distal end of the housing, so that the liquid discharge port is in communication with the liquid outlet of the housing through the inner cavity of the compensating tube; and

[0012] A rectifier is provided in the blood flow channel and can guide blood to flow from the periphery of the motor to the impeller.

[0013] The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will become apparent from the description, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments or descriptions of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0015] Figure 1 is a schematic diagram of the anatomical structure of the human heart.

[0016] FIG2 is a schematic diagram of a blood pump according to an embodiment of the present application being applied to assist the right ventricle in pumping blood.

[0017] FIG3 is a schematic diagram of blood flow during cardiac contraction after a blood pump according to an embodiment of the present application is implanted in the heart.

[0018] FIG4 is a schematic diagram of blood flow during cardiac diastole after the blood pump shown in FIG3 is implanted in the heart.

[0019] FIG5 is a front view of a blood pump according to an embodiment of the present application.

[0020] FIG6 is a cross-sectional view of the blood pump shown in FIG5 along line AA.

[0021] FIG7 is a partial enlarged view of point B in the blood pump shown in FIG6 .

[0022] FIG8 is a schematic diagram of an explosion of the blood pump shown in FIG5 .

[0023] FIG9 is a further exploded schematic diagram of the blood pump shown in FIG8 .

[0024] FIG10 is an axial schematic diagram of the compensation tube in the blood pump shown in FIG6 .

[0025] FIG11 is an axial schematic diagram of the connecting tube in the blood pump shown in FIG6 .

[0026] FIG12 is an axial schematic diagram of the outlet tube of the blood pump shown in FIG6 .

[0027] FIG13 is an axial schematic diagram of the inlet tube of the blood pump shown in FIG6.

[0028] FIG14 is an axial schematic diagram of the housing and catheter of the blood pump shown in FIG6.

[0029] FIG15 is a schematic structural diagram of a blood pump according to another embodiment of the present application.

[0030] FIG16 is a schematic diagram of the internal structure of the blood pump shown in FIG15 .

[0031] FIG17 is a partial enlarged view of point C in the blood pump shown in FIG16 .

[0032] FIG18 is a partial enlarged view of point E in the blood pump shown in FIG17 .

[0033] FIG19 is an assembly diagram of the catheter, drive unit, and rectifying device of the blood pump shown in FIG16 .

[0034] FIG20 is an assembly diagram of the catheter and motor of the blood pump shown in FIG19.

[0035] FIG21 is a schematic diagram of a partial structure of the assembly of the catheter and the motor of the blood pump shown in FIG20 .

[0036] FIG22 is a schematic structural diagram of a rectifier device of a blood pump according to an embodiment of the present application.

[0037] FIG23 is a schematic diagram of the rectification principle of the rectifier device shown in FIG22 . DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solutions and advantages of this application more clearly understood, the following further describes this application in detail with reference to the accompanying drawings, i.e., embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0039] It should be noted that when an element is referred to as being “fixed on” or “disposed on” another element, it may be directly on the other element or indirectly on the other element. When an element is referred to as being “connected to” another element, it may be directly connected to the other element or indirectly connected to the other element.

[0040] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. Throughout the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0041] In order to illustrate the technical solution of the present application, the following description is given with reference to specific drawings and embodiments.

[0042] In this document, the “proximal end” is defined as the end closer to the operator; the “distal end” is defined as the end farther from the operator.

[0043] Please refer to Figure 1, which is a diagram of the anatomical structure of the human heart. In related technologies, interventional assist devices are also called blood pumps, which are mainly used to penetrate from the patient's blood vessels into the ventricles to assist the ventricles in pumping blood. To facilitate understanding of the application of blood pumps, the following is a brief description of the heart structure and blood flow direction. The human body's blood circulation includes systemic circulation and pulmonary circulation. Among them, blood is ejected from the left ventricle 30 through the aortic valve 31 to the aorta 32, and then flows through the aorta 32 to the capillaries throughout the body for substance exchange, so that arterial blood becomes venous blood, and the venous blood then flows back to the right atrium 22 through the superior vena cava 21 and the inferior vena cava 20. This circulation is called systemic circulation. Next, the blood in 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 to the pulmonary artery 26. Then, it flows through the pulmonary artery 26 to the pulmonary capillaries at all levels for gas exchange, turning venous blood into arterial blood. The arterial blood finally flows back to the left atrium 28 from the pulmonary vein 27, and the blood in the left atrium 28 enters the left ventricle 30 through the mitral valve 29. This circulation is called pulmonary circulation.

[0044] A relatively common type of blood pump is the left ventricular assist pump. This type of left ventricular assist pump has a relatively long pump body. When the left ventricular assist pump is applied to the left ventricle 30, it is usually inserted from the aorta 32 through the aortic valve 31, so that the blood inlet of the left ventricular assist pump extends into the left ventricle 30, while the blood outlet of the left ventricular assist pump is located in the aorta 32, that is, only the distal end of the left ventricular assist pump extends into the left ventricle 30. Thus, the left ventricular assist pump can assist 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 part of the aorta 32 through the aortic valve 31 to enter the left ventricle 30 is relatively close to the same axial direction, so this left ventricular assist pump with a relatively long pump body can adapt to the delivery path of the left ventricle 30.

[0045] If the patient's right ventricle 24 has a functional disorder, a blood pump is also needed to assist the right ventricle 24 in pumping blood. Therefore, people have also considered using a left ventricular assist pump to assist the right ventricle 24 in pumping blood. However, the delivery path of the blood pump implanted in the right ventricle is generally from the inferior vena cava 20 or the superior vena cava 21 to the right atrium, tricuspid valve 23, right ventricle 24, pulmonary valve 25 and then to the pulmonary artery 26. It can be seen that the delivery path of the blood pump implanted in the right ventricle has many tortuous paths, is short, and has a complex internal structure. Because the axial length of the pump body of the traditional left ventricular assist pump is too long, it is difficult to pass through the delivery path of the right ventricle 24. Therefore, this left ventricular assist pump is difficult to apply to the right ventricle 24.

[0046] Therefore, a right ventricular assist pump has emerged on the market. The axial length of the pump body of this right ventricular assist pump is designed to be relatively short, allowing it to pass from the right ventricle 24 through the pulmonary valve 25 and 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 the pulmonary valve 25 and be held in place by the pulmonary valve 25. Since the pulmonary valve 25 alternately opens and closes with the heartbeat, the pump body of this right ventricular assist pump is easily displaced axially by the pulmonary valve 25 during the alternating opening and closing of the pulmonary valve 25, which may cause the pump body to become loose from the pulmonary valve 25.

[0047] Please refer to Figures 3 and 4. In order to solve the above problems, the present application provides a blood pump 10, which is mainly used as a right ventricular assist pump. The blood pump 10 can be installed from the right ventricle 24 to the pulmonary artery 26 to assist the right ventricle 24 in pumping blood into the pulmonary artery 26, thereby relieving the pressure of the right ventricle 24 and reducing the risk of the blood pump being loosened 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 the medical device close to the physician or operator is usually called the proximal end, and the end away from the physician or operator is called the distal end.

[0048] Referring to Figures 5 and 6 , in one embodiment of a blood pump provided herein, the blood pump 10 includes a housing 100, a drive unit 200, and a cannula assembly 300. The drive unit 200 is configured to drive blood flow and is disposed within the housing 100. The proximal end of the housing 100 is affixed to the proximal end of the drive unit 200 or the catheter 12 of the blood pump 10. A flow gap 500 is formed between the inner surface of the housing 100 and the drive unit 200. The cannula assembly 300 includes a compensating tube 310 affixed to the distal end of the housing 100 and communicating with the flow gap 500 to form a blood flow channel. The housing 100 has a first opening 111 at its proximal end, and a second opening 321 at its distal end. The second opening 321 communicates with the first opening 111 through the blood flow channel.

[0049] 6 , one of the first opening 111 and the second opening 321 can serve as a blood inlet, while the other can serve as a blood outlet. When the blood pump 10 is used as a right ventricular assist pump, the first opening 111 serves as the blood inlet, and the second opening 321 serves as the blood outlet. After the blood pump 10 is activated, the drive unit 200 drives blood F from the first opening 111 into the flow gap 500 . The blood F then flows from the flow gap 500 into the compensation tube 310 , and finally is discharged from the second opening 321 , thereby assisting in decompressing the right ventricle 24 and reducing overexpansion during right ventricle 24 congestion.

[0050] In other embodiments, the blood pump 10 can function as a left ventricular assist pump. When the blood pump 10 functions 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 activated, the drive unit 200 drives blood from the second opening 321 into the compensation tube 310, then from the compensation tube 310 into the flow gap 500, and finally out of the first opening 111.

[0051] It is understood that in the blood pump 10 described above, the casing 100 and the drive unit 200 constitute the pump body 11 of the blood pump 10 and are the hard portion. Because the drive unit 200 is disposed within the casing 100, the axial length of the pump body 11 is reduced. When the blood pump 10 is implanted, the compensating tube 310 of the blood pump 10 enters the right ventricle 24 before the pump body 11. The compensating tube 310 can elastically deform within the right ventricle 24, allowing the pump body 11, which has a shorter axial length, to enter the right ventricle 24 after the compensating tube 310. Consequently, the pump body 11 of the blood pump 10 and its compensating tube 310 can deflect upward within the right ventricle 24 to pass through the pulmonary valve 25 and extend into the pulmonary artery 26. Because the compensating tube 310 appropriately compensates for the shortened axial length of the pump body 11, not only the pump body 11 but also the compensating tube 310 can be clamped to the pulmonary valve 25, effectively increasing the axial length of the blood pump 10 that can be used to clamp and position the pulmonary valve 25. Therefore, when the blood pump 10 is inserted into the pulmonary valve 25, both the pump body 11 and the compensating tube 310 can be clamped to the pulmonary valve 25, thereby reducing the risk of the pump body 11 falling off the pulmonary valve 25.

[0052] Specifically, as shown in Figure 3, one of the pushing paths of the blood pump 10 is that the pump body 11 of the blood pump 10 penetrates the right atrium 22 from the inferior vena cava 20, then passes through the tricuspid valve 23 from the right atrium 22 to enter 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 liquid inlet 1240 of the blood pump 10 can be in the right ventricle 24, and the liquid outlet 220a of the blood pump 10 is in the pulmonary artery 26. Another pushing 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 to enter 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 liquid inlet 1240 of the blood pump 10 can be in the right ventricle 24, and the liquid outlet 220a of the blood pump 10 is in the pulmonary artery 26.

[0053] As can be seen in Figures 1 and 3 , the delivery path of the blood pump 10 from the inferior vena cava 20 or superior vena cava 21 to the pulmonary artery 26 is characterized by a short path, numerous bends, and complex internal structures. Because the pump body 11 of the blood pump 10 has a relatively short axial length and its compensating tube 310 is elastically deformable, the pump body 11 can pass through the various bends of the shorter delivery path and then bend upward (or deflect) through the narrow right ventricle 24 to enter the pulmonary artery 26. During the process of the pump body 11 turning upward from the right ventricle 24 into the pulmonary artery 26, the compensating tube 310 enters the right ventricle 24 before the pump body 11. The compensating tube 310 elastically deforms within the right ventricle 24, allowing the pump body 11 to subsequently enter the right ventricle 24 and also to turn (or deflect) upwards toward 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 in 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 passing through the delivery path.

[0054] It's easy to understand that the heart 20 is constantly contracting and expanding. As shown in Figure 3 , when the heart 20 contracts, the pulmonary artery 26 opens, allowing blood to flow from the right ventricle 24 into the pulmonary artery 26. At this point, the clamping force of the pulmonary valve 25 on the blood pump 10 decreases. Consequently, driven by the impact of blood flowing in the direction Q1, the pump body 11 of the blood pump 10 tends to move into the pulmonary artery 26. Similarly, as shown in Figure 4 , when the heart 20 expands, the pulmonary valve 25 closes, carrying the pump body 11 of the blood pump 10 along the direction Q2 into the right ventricle 24.

[0055] Therefore, the blood pump 10 of the present application, by disposing the drive unit 200 inside the casing 100, shortens the axial length of the pump body 11 to approximately equal the axial length of the casing 100. Thus, after the compensating tube 310 of the blood pump 10 enters the right ventricle 24, the compensating tube 310 only needs to undergo a small elastic deformation, thereby enabling the shorter pump body 11 to also enter the right ventricle 24. Due to the short axial length of the pump body 11 and the elastic deformation of the compensating tube 310, the pump body 11 of the blood pump 10 can deflect upward in the right ventricle, and then pass through the pulmonary valve 25 to extend into the pulmonary artery 26, so that the first opening 111 can be located in the right ventricle 24, while the second opening 321 of the blood pump 10 is located in the pulmonary artery 26. Furthermore, the compensating tube 310 and the pump body 11 are arranged axially, so not only the pump body 11 but also the compensating tube 310 can be clamped to the pulmonary valve 25. This effectively increases the axial length of the blood pump 10 that can be used to clamp and position the pulmonary valve. Therefore, after the blood pump 10 passes through the pulmonary valve 25, as the pulmonary valve 25 alternately opens and closes with the heartbeat, the pulmonary valve 25 can be clamped to at least one of the pump body 11 and the compensating tube 310, thereby reducing the risk of the blood pump 10 becoming loose from the pulmonary valve 25.

[0056] In one embodiment, both the first opening 111 and the second opening 321 of the blood pump 10 can communicate with the blood flow path. That is, either the first opening 111 or the second opening 321 can serve as a blood inlet, while the other can serve as a blood outlet. This application does not limit which serves as the blood inlet. However, for ease of understanding and explanation, the following embodiments will illustrate specific implementations of the blood pump 10 provided herein using the first opening 111 as the blood inlet and the second opening 321 as the blood outlet. It should be understood that the reverse is also applicable, so further explanation will not be given.

[0057] Referring to Figure 3 , in one embodiment, the blood pump 10 is capable of passing through the inferior vena cava 20, right atrium 22, right ventricle 24, and pulmonary valve 25 to extend into the pulmonary artery 26, with the first opening 111 located within the right ventricle 24 and the second opening 321 located within the pulmonary artery 26. Thus, during operation, the blood pump 10 can pump blood directly into the pulmonary artery 26, reducing the risk of excessive blood accumulation in the right ventricle 24 and resulting in excessive dilation of the right ventricle 24. This improves the safety of the blood pump 10. Furthermore, because the first opening 111 is located within the right ventricle 24, the blood pump 10 can also direct blood from the superior vena cava 21 and inferior vena cava 20 into the right ventricle 24 via the right atrium 22 during operation, assisting in cardiac transfusion in the heart 20. The blood flow path and direction within the blood pump 10 are shown as dashed arrows F in Figure 6 .

[0058] Referring to Figures 5 and 6 , conventional left ventricular assist pumps typically have an elastic sleeve connected to the distal end of the pump body 11. Only a portion of this elastic sleeve extends into the left ventricle. Therefore, to accommodate the left ventricular delivery path, the length of this elastic sleeve is often several times the length of the pump body 11. This elastic sleeve is typically pre-shaped into a curved shape, allowing it to elastically deform in the direction of the bend. In one embodiment of the present application, a compensating tube 310 is used to appropriately compensate for the shortened length of the pump body 11 after the drive unit 200 is housed within the housing 100. Therefore, the axial length of the compensating tube 310 is designed to be relatively short to ensure that after the entire compensating tube 310 can enter the right ventricle 24, the pump body 11 of the blood pump 10 can also enter the right ventricle 24. Optionally, the compensating tube 310 has a first axial length L1 that 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, 22 mm, 25 mm, 28 mm, 30 mm, 34 mm, etc.

[0059] Furthermore, since the axial length of the compensation tube 310 is relatively short and a large degree of directional bending is not required during implantation in the right ventricle, in this embodiment, the compensation tube 310 is configured as a straight tube extending along the axial direction of the drive unit 200. This configuration allows the compensation tube 310 of the present application to eliminate the process steps of bending and shaping, reducing manufacturing difficulty and improving production efficiency. Since the compensation tube 310 is a straight tube, the compensation tube 310 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. In this way, the blood flow channel formed by the flow gap 500 and the compensation tube 310 can be extended linearly along the axial direction, and the blood flow channel has less resistance to blood flow, so that blood can pass through the blood flow channel more smoothly.

[0060] Please refer to Figure 6. In one embodiment, the outer circumferential surface of the compensation tube 310 is set to be flush with the outer circumferential surface of the housing 100 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 implantation process of the blood pump 10, reducing the obstruction to the blood flow outside the blood pump 10, and also reducing the probability of blood stasis on the surface of the blood pump 10 and forming a thrombus.

[0061] Please refer to Figure 6. In one embodiment, since the inner circumferential surface of the compensation tube 310 and the inner circumferential surface of the casing 100 both form the side wall of the blood flow channel, the inner circumferential surface of the compensation tube 310 and the inner circumferential surface of the casing 100 are set to be flush along 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 casing 100, so that the side wall of the blood flow channel becomes 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 blood pumping efficiency of the blood pump 10.

[0062] Referring also to FIG6 , in one embodiment, the compensating 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 greater than or equal to 0.7 and less than or equal to 1.3, i.e., 0.7≤L1 / L2≤1.3, i.e., 0.7L2≤L1≤1.3L2. Since the housing 100 and the drive unit 200 constitute the rigid portion of the pump body 11 of the blood pump 10, and the compensating tube 310 constitutes the elastic portion, and the axial length of the rigid portion of the pump body 11 is substantially equal to the length of the housing 100, the ratio of the first axial length L1 of the compensating tube 310 to the second axial length L2 of the housing 100 is defined as 0.7≤L1 / L2≤1.3, which is equivalent to defining the size ratio of the elastic portion to the rigid portion of the blood pump 10 as 0.7≤L1 / L2≤1.3. This can prevent the compensation tube 310 from being too long, reducing the difficulty of the pump body 11 entering the right ventricle; and the size of the hard 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.

[0063] In one embodiment, the compensating tube 310 can be configured as a multi-layer composite structure to balance flexible deformation capability, support capability, and toughness. For example, the compensating tube 310 includes an inner membrane, an outer membrane, and an elastic coil disposed between the inner membrane and the outer membrane to form a compensating tube 310 that balances elastic deformation and connection support capability. It is easy to understand that the inner membrane is attached to the inner side of the elastic coil to form an inner peripheral wall for blood circulation, and the outer membrane is attached to the outer side of the elastic coil to form the outer peripheral wall of the compensating tube 310. Of course, the compensating tube 310 is not limited to a three-layer structure. The number of layers of the layered structure of the compensating tube 310 and the materials used in each layer can also be adaptively adjusted according to actual needs. For example, a braided layer can be added to the compensating tube 310 to improve toughness.

[0064] In one embodiment, the housing 100 has a non-elastic structure. Optionally, the housing 100 is made of a hard material. This allows the housing 100 to be highly lightweight, thereby creating a structurally stable flow gap 500 between the housing 100 and the drive unit 200 for stable blood transport. For example, the hard material may be a metal or a polymer material.

[0065] 6 and 7 , 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 is capable of driving the impeller 220 to rotate, thereby driving blood flow. Considering that the first axial length L1 of the compensating tube 310 is relatively short, as the blood pump 10 travels along the right ventricular delivery path from the right atrium to the right ventricle, through the pulmonary valve, and into the pulmonary artery, the delivery path is relatively narrow, causing the blood pump 10 to bend at the proximal end of the compensating tube 310. If the impeller 220 extends from the interior of the housing 100 into the compensating tube 310, when the proximal end of the compensating tube 310 bends and deforms, the inner circumferential surface of the compensating tube 310 may contact or abut against the impeller 220, thereby interfering with the impeller 220 and hindering its rotation.

[0066] To this end, the housing 100 optionally includes a distal port 122 for communication with the compensating tube 310. The distal end of the impeller 220 includes a distal point 223, which is farthest from the motor 210. The distal point 223 is located within the housing 100 and does not extend beyond the distal port 122, thereby preventing the impeller 220 from protruding into the compensating tube 310. Specifically, because the housing 100 has a relatively rigid structure, it provides a spatially stable inner cavity, facilitating stable rotation of the impeller 220. When the blood pump 10 is routed along the right ventricular delivery pathway to the pulmonary artery, even if the blood pump 10 bends proximal to the compensating tube 310, since the impeller 220 does not protrude into the compensating tube 310, the inner circumferential surface of the compensating tube 310 will not contact the impeller 220, thereby preventing the impeller 220 from rotating.

[0067] Referring to Figures 7 and 8 , in one embodiment, the distal end 223 of the impeller 220 and the distal nozzle 122 are both located on a first plane PL, which is a plane perpendicular to the axis of the drive unit. In other words, the distal end of the impeller 220 extends to the distal nozzle 122 of the housing 100, fully utilizing the axial space of the housing 100 to accommodate a longer impeller 220. This increases the size of the impeller 220, thereby driving more blood flow and increasing the pumped blood flow rate. Of course, in other embodiments, the distal end 223 of the impeller 220 may also be spaced axially from the distal nozzle 122PL.

[0068] Please refer to Figures 7, 9 and 10. In one embodiment, a first insertion portion 121 is provided at the distal end of the housing 100, and a second insertion portion 311 is provided at the proximal end of the compensation tube 310. The second insertion portion 311 is sleeved on the outer circumferential surface of the first insertion portion 121 and is bonded and fixed to the outer circumferential surface of the first insertion portion 121.

[0069] Please refer to Figures 6 and 7. Optionally, the overlapping area of ​​the first insertion portion 121 and the second insertion portion 311 has a third axial length L3. The ratio of the third axial length L3 to the first axial length L1 of the compensation tube 310 is greater than or equal to 0.1 and less than or equal to 0.3, that 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.

[0070] Specifically, due to the short length of the compensation tube 310, when the compensation tube 310 bends and deforms, the proximal end of the compensation tube 310 will be subjected to a large bending force, and the connection between the second insertion portion 311 and the first insertion portion 121 will bear a large bending force. By limiting the third axial length L3 of the overlapping area of ​​the first insertion portion 121 and the second insertion portion 311, the ratio of the third axial length L3 to the first axial length L1 of the compensation tube 310 is 0.1≤L 3 / When L1 is ≤ 0.3, the second insertion portion 311 has a larger area for interfitting with the first insertion portion 121, thereby strengthening the connection between the second insertion portion 311 and the first insertion portion 121. This ensures that when the compensating tube 310 bends and deforms, even if the proximal end of the compensating tube 310 is subjected to a significant bending force, the connection between the second insertion portion 311 and the first insertion portion 121 will not easily loosen or fall off, effectively improving the safety of the blood pump 10. In other words, by properly setting the third axial length L3, the stability of the connection between the housing 100 and the compensating tube 310 is improved.

[0071] Referring to Figure 7 , in a conventional blood pump, the motor is typically directly connected to the cannula assembly, with only the impeller disposed within the cannula assembly. The motor's outer diameter is typically consistent with the cannula assembly's outer diameter, so the impeller's diameter is typically smaller than the motor's. In the present application, however, since the drive unit 200 of the blood pump 10 is disposed within the housing 100, both the motor 210 and the impeller 220 are disposed within the housing 100. Assuming the motor 210 has a first diameter D1, the impeller 220 has a second diameter D2, and the housing 100 has a third diameter D3, the third diameter should be greater than the first diameter, and the third diameter should be greater than the second diameter, i.e., D3>D1, and D3>D2.

[0072] Given this, the internal space of the casing 100 can be fully utilized to design the impeller 220 larger. Therefore, optionally, the relationship between the first diameter D1 of the motor 210, the second diameter D2 of the impeller 220, and the third diameter D3 of the casing 100 is as follows: the third diameter is larger than the second diameter, and the second diameter is larger than the first diameter, i.e., D3>D2>D1. In other words, compared to conventional blood pumps, the diameter of the impeller 220 of the blood pump 10 of the present 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 should be understood that the diameter D1 of the motor 210 is the maximum radial dimension of the motor 210, and the diameter D2 of the impeller 220 is also the maximum radial dimension of the impeller 220; the inner diameter D3 of the casing 100 is the inner diameter of the area of ​​the casing 100 that accommodates the motor 210 and the impeller 220.

[0073] Referring to Figure 7 , in one embodiment, impeller 220 comprises a hub 221 and blades 222, with blades 222 disposed on the outer periphery of hub 221. Hub 221 and shaft support 211 are axially opposed to each other in the impeller 220's direction. Because impeller 220 is an axial flow impeller, the blood driven by impeller 220 possesses not only axial kinetic energy but also radial kinetic energy. This axial kinetic energy enables the blood to flow rapidly along the axial direction of compensating tube 310 and through the lumen of compensating tube 310.

[0074] Based on this, in order to ensure that the blood can obtain greater axial kinetic energy after passing through the impeller 220, in this embodiment, the diameter of the hub 221 is configured to gradually increase along the direction from the motor 210 to the impeller 220, so that the distance between the outer circumference of the hub 221 and the inner circumference of the casing 100 gradually decreases along the direction of the hub 221's diameter expansion. The diameter expansion direction is the direction from the motor 210 to the impeller 220. This configuration enables the distal end of the hub 221 to have a larger diameter, so that the distance K2 between the outer circumference of the distal end of the hub 221 and the inner circumference of the casing 100 is smaller than the distance K1 between the outer circumference of the proximal end of the hub 221 and the inner circumference of the casing 100, i.e., K2 < K1. Blood F3 enters the impeller 220 at the spacing K1 and is driven by the impeller 220 to rotate spirally, thereby being gradually pushed by the impeller 220 toward the spacing K2. Since the path from the spacing K1 to the spacing K2 gradually becomes narrower, the blood F3 is gradually compressed by the spiral in this process, so that part of the radial potential energy of the blood F3 obtained by being driven spirally by the impeller 220 is converted into axial potential energy, which increases the axial potential energy of the blood F3, thereby increasing the component velocity of the blood F3 along the axial flow, so that the blood F3 flows rapidly through the inner cavity of the compensation tube 310 along the axial direction of the compensation tube 310.

[0075] Referring to Figures 6 and 7 , in one embodiment, the motor 210 includes a motor body 213 and a shaft support 211. The shaft support 211 is 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 and the proximal end of the hub 221 are axially opposed to each other. Furthermore, the diameter of the shaft support 211 gradually decreases along the direction from the motor 210 to the impeller 220. In this way, blood outside the shaft support 211 can be guided by the outer peripheral surface of the shaft support 211 to flow in the direction of its decreasing diameter, thereby being guided by the shaft support 211 to flow into the impeller 220, thereby increasing the blood flow driven by the impeller 220.

[0076] Furthermore, the shaft support seat 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 , that is, D 4min ≤D 1min It is easy to understand that the proximal end of the hub 221 is the minimum radial dimension of the hub 221, and the distal end of the shaft support seat 211 is the minimum radial dimension of the shaft support seat 211. The proximal end of the hub 221 and the distal end of the shaft support seat 211 are opposite and adjacent to each other along the axial direction of the impeller 220. 4min Less than or equal to the first minimum outer diameter D 1min When the blood is guided by the outer peripheral surface of the shaft support seat 211 to flow toward the impeller 220 along its shrinking direction, the blood separated from the distal outer peripheral surface of the shaft support seat 211 can flow to the outer peripheral surface of the hub 221 of the impeller 220, avoiding this part of the blood from colliding with the proximal end surface of the hub 221, thereby reducing the loss of blood kinetic energy.

[0077] In other words, because the radial dimension of shaft support 211 is greater than or equal to that of hub 221 in the area where shaft support 211 and hub 221 are close to each other, shaft support 211 can guide blood smoothly across the transition between shaft support 211 and hub 221. This, on the one hand, improves the smoothness of blood flow, resulting in higher blood pumping efficiency for blood pump 10. On the other hand, it also reduces the chance of blood stagnation and thrombosis at the transition between shaft support 211 and hub 221.

[0078] Referring to Figures 7 to 9 , in one embodiment, the housing 100 includes an inlet pipe 110, a fixing ring 420, and a connecting pipe 120. The inlet pipe 110 and the connecting pipe 120 are respectively connected to the ends of the fixing ring 420. The inlet pipe 110 is provided with a first opening 111. The end of the inlet pipe 110 away from the fixing ring 420 (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 away from the fixing ring 420 (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 420 is fixedly connected to the outer circumference of the motor 210 via the support member 410.

[0079] Specifically, the fixing ring 420 is looped around the outer periphery of the motor 210, and the inner wall surface of the fixing ring 420 is spaced apart from the outer periphery of the motor 210. The inner wall surface of the fixing ring 420 is provided on a plurality of support members 410, and the plurality of support members 410 are fixedly connected to the outer periphery of the motor 210 to support and fix the fixing ring 420. The fixing ring 420 forms the side wall of the middle portion of the housing 100. Therefore, the fixing ring 420 is stably supported by the support members 410, so that the fixing ring 420 serves as a central support on the housing 100, allowing the inlet tube 110 and the connecting tube 120 to maintain a stable relative position relative to the outer surface of the motor 210, thereby improving the structural stability of the blood flow channel formed between the housing 100 and the drive unit 200.

[0080] It is worth mentioning that the shape and structure of the above-mentioned support member 410 are not specifically limited. The support member 410 can be a support rib extending along the radial direction of the motor 210, or a guide plate extending along the axial direction of the motor 210. During assembly, the inlet pipe 110 of the casing 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 420; and the connecting pipe 120 of the casing 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 420. In this way, the casing 100 and the motor 210 are connected and fixed, which improves the convenience of assembly.

[0081] Please refer to Figures 9, 11 and 12. Optionally, the first inserting portion 121 is provided at the distal end of the connecting tube 120, and the connecting tube 120 is plugged into and fitted with the second inserting portion 311 of the compensation tube 310 through the first inserting portion 121.

[0082] Referring to Figures 9, 12, and 13, the distal end of the retaining ring 420 is provided with a seventh insertion portion 421 and an eighth insertion portion 422. The end of the connecting tube 120, distal from the compensating tube 310, is provided with a fifth insertion portion 123. The seventh insertion portion 421 engages with the fifth insertion portion 123. The inlet tube 110 is provided with a sixth insertion portion 116. The eighth insertion portion 422 engages with the sixth insertion portion 116. In this arrangement, the retaining ring 420 is respectively engaged with the connecting tube 120 and the inlet tube 110 to form the housing 100.

[0083] Referring to Figures 9, 13, and 14, in 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 the fixing ring 420; the reducing pipe 113 is sleeved around the outer circumference 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 spaced apart along the circumference of the straight pipe 112, with a first opening 111 formed between each two adjacent connecting arms 114.

[0084] Specifically, the straight tube 112 is arranged in a straight tube shape so that the inner circumference of the straight tube 112 forms a cylindrical surface, thereby reducing the fluid resistance of the blood flow channel. The reducer 113 is arranged in a conical shape. By sleeved on the outer circumference of the connection between the catheter 12 and the drive unit 200, the connection can be wrapped inside the reducer 113 to prevent the adhesive at the connection from being washed off by the blood. The reducer 113 has two interfaces, one of which is an interference fit with the distal outer circumference of the catheter 12, and the other is an interference fit with the proximal outer circumference of the drive unit 200. The straight tube 112, the reducer 113 and the connecting arm 114 can be formed as one piece.

[0085] Furthermore, the inner wall surfaces of the straight tube 112, the fixing ring 420 and the connecting tube 120 are flush along the axial direction to facilitate smooth blood flow. In addition, the outer wall surfaces of the straight tube 112, the fixing ring 420 and the connecting tube 120 are also flush along the axial direction. With this arrangement, the straight tube 112, the fixing ring 420 and the connecting tube 120 are assembled into a regular cylinder. With this arrangement, on the one hand, the outer circumferential surface of the housing 100 can be made smooth and regular, which can reduce damage to human tissue during the implantation of the blood pump 10; on the other hand, the inner circumferential surface of the housing 100 is also relatively smooth and regular, which can reduce the resistance of the blood flow channel to the fluid, reduce the kinetic energy loss of blood circulating in the blood flow channel, improve blood pumping efficiency, and reduce blood cell damage.

[0086] Please refer to Figure 14. In one embodiment, the connecting arm 114 includes a first connecting portion 114a connected to the straight tube 112, and a second connecting portion 114b connecting the first connecting portion 114a and the reducing tube 113; wherein, the connecting arm 114 is located on the outer circumferential surface of the reducing tube 113, and a notch groove 115 is formed between two adjacent second connecting portions 114b, and the notch groove 115 is connected to the proximal end of the first opening 111 along the axial direction of the inlet tube 110.

[0087] When the drive unit 200 operates and generates suction, a portion of the blood F2 is radially drawn into the first opening 111 from the circumference of the inlet tube 110, and then continues to be driven by the drive unit 200 to switch to flowing axially into the flow gap 500. Another portion of the blood F1 can enter the inner side of the first opening 111 axially from the notch 115, and push 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 500, thereby effectively increasing the flow rate of blood entering from the first opening 111 and improving the pumping efficiency of the blood pump 10. In other words, by providing the second connecting portion 114 and the reducing tube 113 to form the notch 115, the smoothness of blood entering the first opening 111 can be improved, thereby reducing the probability of blood congestion at the first opening 111.

[0088] Referring to Figure 14 , a guide surface 114c is further provided on the side of the second connecting portion 114b facing the notch 115. This guide surface 114c is configured to guide blood axially from the notch 115 into the interior of the first opening 111, accelerating blood flow and improving blood pumping efficiency. The guide surface 114c is generally prismatic in shape, with its distal end extending to the side of the proximal end of the first connecting portion 114a.

[0089] Referring to Figures 5, 9, and 10, in one embodiment, the cannula assembly 300 further includes an outlet tube 320, which is fixedly connected to the end of the compensating tube 310 distal 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 (see Figure 11) is provided at the distal end of the compensating tube 310. The third insertion portion 322 engages with the fourth insertion portion 312 to connect the compensating tube 310 to the outlet tube 320. The inner circumferential wall of the outlet tube 320 is axially flush with the inner circumferential wall of the compensating tube 310 to facilitate smooth blood flow. The outer circumferential wall of the outlet tube 320 is axially flush with the outer circumferential wall of the compensating tube 310 to provide a smooth and regular overall appearance for the blood pump 10, facilitating movement of the blood pump 10 within the blood vessel or heart 20.

[0090] 5 and 6 , in one embodiment, the blood pump 10 includes a catheter 12 that extends from the outside to the inside through the proximal end of the housing 100 to connect to the drive unit 200. The proximal end of the housing 100 can be positioned over the catheter 12, the drive unit 200, or the connection between the catheter 12 and the drive unit 200, to directly or indirectly connect to the drive unit 200.

[0091] Referring to FIG. 3 , in one embodiment, the catheter 12 comprises a proximal portion 12a, a distal portion 12b, and a bend 12c. The bend 12c is located between the proximal and distal portions 12a, 12b, and adjacent to the distal portion 12b. The bend 12c is pre-formed into a curved shape to conform to the anatomical shape of a first connection point in the right atrium 22. The first connection point is the connection point between the inferior vena cava 20 and the right atrium 22. Thus, the bend 12c of the catheter 12 conforms to the shape of the connection point between the inferior vena cava 20 and the right atrium 22, enabling the blood pump 10 to enter the right atrium 22 from the inferior vena cava 20 via the first connection point. This reduces the difficulty of the blood pump 10 passing through the bend in the first connection point, improves the smoothness of delivery of the blood pump 10, and reduces damage and discomfort caused by the blood pump 10 to the human body.

[0092] Of course, in another embodiment, the shape of the bend 12c is adapted to the anatomical shape of the second connection point of the right atrium 22. The second connection point refers to the connection point 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 connection 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 connection point. This reduces the difficulty of the blood pump 10 passing through the bend of the second 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] Referring to Figures 15 and 16 , in one embodiment, a blood pump 10 includes a housing 100 and a drive unit 200. The housing 100 is provided with a liquid inlet 111 and a liquid outlet 122. The drive unit 200 is disposed within the housing 100. A blood flow channel 500 is formed between the drive unit 200 and the inner circumference of the housing 100. The blood flow channel 500 connects the liquid inlet 111 and the liquid outlet 122. The proximal end of the housing 100 is fixedly coupled to the proximal end of the drive unit 200 or the catheter 12 of the blood pump 10, thereby ensuring a stable relative position between the housing 100 and the motor 210, thereby forming a structurally stable blood flow channel 500. The drive unit 200 includes a motor 210 and an impeller 220 connected to the distal end of the motor 210.

[0094] Specifically, the blood flow channel 500 may be the flow gap 500 shown in FIG6 ; the liquid inlet 111 may be the first opening 111 of the housing 100 shown in FIG6 ; and the liquid outlet 122 may be the distal end nozzle 122 of the housing 100 shown in FIG6 . The motor 210 can drive the impeller 220 to rotate, thereby driving blood to flow from the liquid inlet 111 through the blood flow channel 500 to the liquid outlet 122.

[0095] Because the blood flow channel 500 is formed between the outer periphery of the drive unit 200 and the inner circumference of the housing 100, the portion of the blood flow channel 500 located between the outer circumference of the motor 210 and the inner circumference of the cannula 100 is an annular channel. As a result, when blood flows from the annular channel around the motor 210 into the impeller 220, the flow area and shape of the blood flow channel 500 change, causing the blood flow direction to change. This can lead to collision and interference between blood streams, resulting in chaotic blood flow and loss of blood kinetic energy.

[0096] Referring to Figures 16 and 17 , in view of the above-mentioned issues, in one embodiment, the blood pump 10 further includes a rectifier 400 disposed within the blood flow channel 500. The rectifier 400 is capable of guiding blood from the periphery of the motor 210 toward the impeller 220. Specifically, the portion of the blood flow channel 500 located between the outer circumference of the motor 210 and the inner circumference of the cannula 100 forms a relatively narrow annular channel. When blood within this annular channel flows into the rectifier 400, it is rectified into an orderly flow along the axial direction. The rectifier 400 then guides the blood axially toward the impeller 220, ensuring an orderly flow of blood toward the impeller 220. This reduces kinetic energy loss upon entry, effectively increases the blood flow velocity driven by the impeller 220, and thereby improves the blood flow rate driven by the impeller 220, thereby enhancing the blood pumping efficiency of the blood pump 10.

[0097] It should be noted that although the direction of each blood flow stream in impeller 200 will also change, the directional changes of the blood flow streams driven by impeller 220 are regular and predictable. Compared with a fluid with a chaotic flow direction, a fluid with a stable flow direction obviously has less resistance. The blood pump provided by this application is described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0098] In one embodiment, the liquid outlet 122 of the blood pump 10 can be used directly as a blood outlet (as shown in FIG2 ). In this case, when the blood pump 10 is inserted into the right ventricle, the liquid inlet 111 of the blood pump 10 is located within the right ventricle 24, and the liquid outlet 122 of the blood pump 10 extends into the pulmonary artery 26. The blood pump 10 can discharge blood directly from the liquid outlet 122 into the pulmonary artery 26. In this embodiment, the liquid outlet 122 can be provided on the sidewall of the distal end of the housing 100.

[0099] Considering that the housing 100 and the drive unit 200 constitute the pump body 11 of the blood pump 10, and because the drive unit 200 is disposed within the housing 100, the axial length of the pump body 11 is reduced. When the blood pump passes through the pulmonary valve 25 and extends into the pulmonary artery 26, the pump body 11 of the blood pump 10 is positioned on the pulmonary valve 25. However, the pulmonary valve 25 alternates between opening and closing with the heartbeat. As shown in FIG6 , when the heart 20 contracts, 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. Consequently, driven by the impact of blood flowing in the direction Q1, the pump body 11 of the blood pump 10 tends to move into the pulmonary artery 26. Similarly, as shown in FIG5 , when the heart 20 expands, the pulmonary valve 25 closes. The pulmonary valve 25 tends to move along the Q2 direction, carrying the pump body 11 of the blood pump 10, into the right ventricle 24. Therefore, if the axial dimension of the pump body 11 of the blood pump 10 is too short, the pump body 11 of the blood pump 10 may easily fall off the pulmonary valve 24 during the alternating opening and closing of the pulmonary valve 24, affecting the safety and reliability of the blood pump 10.

[0100] 15 to 17 , in view of the above, in another embodiment, the blood pump 10 may further include a cannula assembly 300 having a drain port 321. The cannula assembly 300 includes a compensating tube 310 that is fixedly connected to and communicates with the distal end of the housing 100, such that the drain port 321 communicates with the liquid outlet 122 of the housing 100 through the inner lumen of the compensating tube 310.

[0101] As shown in FIG16 , in this case, the drain port 321 serves as a blood outlet. The drain port 321 may be the second opening 321 of the housing 100 shown in FIG6 . When the blood pump 10 is inserted into the right ventricle, the inlet 111 of the blood pump 10 is located within the right ventricle, and the drain port 321 of the blood pump 10 is located within the pulmonary artery. After the blood pump 10 is activated, blood in the right ventricle 24 enters the blood flow channel 500 of the blood pump 10 through the inlet 111, is discharged from the blood flow channel 500 through the outlet 122 into the lumen of the compensation tube 310, then flows through the lumen of the compensation tube 310 to the drain port 321, and finally is discharged from the drain port 321 into the pulmonary artery 26.

[0102] Therefore, after the compensating tube 310 of the blood pump 10 of the present application enters the right ventricle 24 before the pump body 11, the compensating tube 310 only needs to undergo a small elastic deformation to allow the shorter pump body 11 to enter the right ventricle 24. Because the axial length of the pump body 11 is relatively short and the compensating tube 310 can elastically deform, the pump body 11 of the blood pump 10 can deflect upward within the right ventricle, passing through the pulmonary valve 25 and extending into the pulmonary artery 26. This allows the liquid inlet 111 to be located within the right ventricle 24, while the liquid outlet 321 of the blood pump 10 is located in the pulmonary artery 26. Furthermore, the compensating tube 310 and the pump body 11 are axially arranged, so that not only the pump body 11 but also the compensating tube 310 can be clamped to the pulmonary valve 25, effectively increasing the axial length of the blood pump 10 available for clamping and positioning the pulmonary valve. Therefore, after the blood pump 10 passes through the pulmonary valve 25, the pulmonary valve 25 can be clamped on at least one of the pump body 11 and the compensation tube 310 during the process of the pulmonary valve 25 alternatingly opening and closing with the beating of the heart, thereby reducing the risk of the blood pump 10 loosening from the pulmonary valve 25.

[0103] Obviously, in the present application, the sleeve assembly 300 is not necessary. It is only necessary that the axial length of the sleeve 100 is long enough so that the pump body 11 is not easily detached from the pulmonary valve 25 .

[0104] Referring to Figures 16 and 17, in one embodiment, the motor 210 includes a motor body 213 and a shaft support seat 211 connected to the distal end of the motor body 213. The motor 210 also includes a motor shaft 212, which extends from the motor body 213 and passes through the shaft support seat 211 to connect to the impeller 220. Optionally, the blood flow channel 500 includes a drainage section 510, a straightening section 520, and a pressurizing section 530 that are connected in sequence. The drainage section 510 is located between the outer circumference of the motor body 213 and the inner circumference of the casing 100 and is connected to the liquid inlet 111. The straightening section 520 is located between the outer circumference of the shaft support seat 211 and the inner circumference of the casing 100; and the pressurizing section 530 is located between the impeller 220 and the inner circumference of the casing 100 and is connected to the liquid outlet 122. The rectifying device 400 is disposed in the rectifying section 520 , so that the blood transported by the drainage section 510 can be rectified into an orderly fluid flowing axially, and then introduced into the boosting section 530 for driving the impeller 200 .

[0105] Specifically, motor 210 includes a motor shaft 212, which extends from the distal end of motor 210 and passes through shaft support 211 to connect to impeller 220. The proximal end of shaft support 211 is connected to and covers the distal end of motor 210. Rectifier 400 is fixedly attached to the outer circumference of shaft support 211.

[0106] Because drainage section 510 is formed by the separation of motor 210 and housing 100, and motor 210 has a generally regular shape, drainage section 510 forms a relatively regular annular channel, with a relatively regular flow area and flow path shape throughout drainage section 510. After blood F flows out of the distal end of drainage section 510, it is susceptible to turbulent flow at the distal end of drainage section 510 due to the changes in the flow area and flow path between drainage section 510 and pressurizing section 530, and the suction force of impeller 220. Therefore, in this embodiment, a rectifying section 520 is provided between the drainage section 510 and the pressurizing section 530 for transition, and a rectifying device 400 is provided within the rectifying section 520. When the blood pump 10 is in operation, the blood F first enters the drainage section 510 of the blood flow channel 500 from the liquid inlet 111, then flows sequentially through the rectifying section 520 and the pressurizing section 530 of the blood flow channel 500, and finally flows toward the liquid outlet 122. Within the rectifying section 520, the rectifying device 400 can rectify the blood flowing out of the distal end of the drainage section 510, thereby rectifying the blood into an orderly fluid flowing along the axial direction, and then orderly directing the fluid to the impeller 220 of the pressurizing section 530.

[0107] Please refer to Figures 16 to 18. In one embodiment, the impeller 220 includes a hub 221 and blades 222 arranged on the outer periphery of the hub 221. The outer diameter of the motor body 213 is larger than the outer diameter of the hub 221. Preferably, the outer diameter of the shaft support seat 211 is gradually reduced in the direction from the motor 210 to the impeller 220, so that the outer peripheral surface of the shaft support seat 211 forms a conical guide surface 211a. The conical guide surface 211a can guide the blood flow in the rectifying channel 404 to gradually deflect toward the central axis of the impeller 220, and then flow to the central area of ​​the impeller 220. That is, the blood can be gradually guided to the central area of ​​the impeller 220 through the shaft support seat 211 to adapt to the radial size difference between the motor 210 and the hub 221 of the impeller 220.

[0108] Please refer to Figures 16 to 18. Furthermore, the rectifying device 400 includes a plurality of rectifying plates 410; the plurality of rectifying plates 410 are arranged on the conical guide surface 211a at intervals along the circumference of the shaft support seat 211. The rectifying plates 410 can be integrally formed with the shaft support seat 211. Specifically, the plurality of rectifying plates 410 are fixed on the conical guide surface 211a at intervals along the circumference of the shaft support seat 211, and a rectifying channel 404 is formed between each two adjacent rectifying plates 410. When blood flows into the rectifying device 400, the blood is separated by the rectifying plates 410 and flows through the rectifying channels 404 on both sides of the rectifying plates 410. The blood passing through the rectifying channels 404 can also be guided by the outer peripheral surface of the shaft support seat 211 to flow toward the impeller 220, which helps to accelerate the blood passing through the rectifying channels 404.

[0109] Optionally, the outer edge of the rectifier plate 410 away from the conical guide surface 211a is parallel to the motor shaft 212. This arrangement allows the blood in the rectifier channel 404 to be confined between the two rectifier plates 410 and the conical guide surface 211a. The two rectifier plates 410 and the conical guide surface 211a can jointly guide the blood in the rectifier channel 404 to flow toward the impeller 220, which helps to accelerate the flow of blood into the impeller 220 and increase the blood flow rate. Because the outer edge of the rectifier plate 410 away from the conical guide surface 211a is parallel to the motor shaft 212, the rectifier plate 410 can obtain a larger guide area and can guide more blood flow. The outer edge can be composed of a first side edge 401 and a second side edge 402. It should be noted that in other embodiments, the rectifier plate 410 of the rectifier device 400 does not need to be fixed to the shaft support seat 211, but can be fixed to the inner circumferential surface of the housing 100.

[0110] Referring to Figures 16 to 18, in one embodiment, the rectifier device 400 includes a plurality of rectifier plates 410, which are fixed to the outer circumferential surface of the motor 210 and spaced apart along the circumference of the motor 210. The plurality of rectifier plates 410 extend axially along the motor 210 to form a linearly extending rectifier channel 404 between two adjacent rectifier plates 410. In other words, the rectifier channel 404 extends linearly along the axial direction of the motor 210 to guide blood to flow axially into the impeller 220. In this way, the plurality of rectifier plates 410 can define a rectifier channel 404 in pairs, thereby providing the rectifier device 400 with a plurality of linearly extending rectifier channels 404 spaced apart along the circumference of the shaft support 211. As described above, the rectifier plates 410 can be fixed to the outer circumferential surface of the shaft support 211 or to the inner circumferential surface of the housing 100.

[0111] Based on this, when blood flows into the rectifying device 400, the blood is divided by the multiple rectifying channels 404 of the rectifying device 40 into multiple orderly blood flows that flow stably along the axial direction. These orderly blood flows will flow axially into the impeller 220. Preferably, the multiple rectifying channels 404 correspond to the spaces between the multiple blades 222 of the impeller 220, so that each rectifying channel 404 guides the blood into the corresponding space, reducing the collision between the blood and the ends of the blades 222.

[0112] Referring to Figures 17 to 20 , in one embodiment, the rectifier plate 410 includes a distal plate 411 and a proximal plate 412 . The distal plate 411 and the proximal plate 412 are arranged and connected along the axial direction of the motor 210 . The distal plate 411 is adjacent to the impeller 220 . The distal plate 411 has a first side 401 that is distal to the outer circumference of the motor 210 . The proximal plate 412 has a second side 402 that is distal to the outer circumference of the motor 210 . The second side 402 extends in the same direction as the first side 401 . The first side 401 and the second side 402 together constitute the outer side of the rectifier plate 410 .

[0113] Optionally, at least one of the first side 401 and the second side 402 is fixedly connected to the inner circumferential surface of the housing 100. This configuration allows the rectifying plate 410 to not only guide blood to flow axially toward the impeller 220, but also to be supported between the drive unit 200 and the housing 100 to ensure that a stable blood flow channel 500 is formed between the drive unit 200 and the housing 100, thereby facilitating stable blood transport through the blood flow channel 500.

[0114] Optionally, the rectifying plate 410 can be fixedly connected to the inner circumference of the casing 100 via the first side 401; or, the rectifying plate 410 can be fixedly connected to the inner circumference of the casing 100 via the second side 402; or, both the first side 401 and the second side 402 are fixedly connected to the inner circumference of the casing 100.

[0115] 16 and 17 , since the distal plate 411 is adjacent to the impeller 220, after blood enters the inlet end of the rectifying channel 404, a portion of the blood will flow along the proximal plate 412 of the rectifying plate 410 toward the distal plate 411, and then be guided by the distal plate 411 into the impeller 220. Considering that if the first side 401 of the distal plate 411 is also fixed to the inner circumferential surface of the housing 100, the entire plate surface of the rectifying plate 410 will be connected to the inner circumferential surface of the housing 100. The portion of blood that flows along the proximal plate 412 toward the distal plate 411 may adhere to the inner circumferential surface of the housing 100, thereby clinging to the inner circumferential surface of the housing 100. This makes it difficult for the blood to be directed to the impeller 220 and thus difficult to be driven by the impeller 220.

[0116] Referring to Figures 17, 18, and 20, in view of the above, in this embodiment, the first side 401 is spaced apart from the inner circumference of the casing 100, and the second side 402 is fixedly connected to the inner circumference of the casing 100. Specifically, the second side 402 of the proximal plate 412 protrudes radially relative to the first side 401 of the distal plate 411, thereby enabling the second side 402 to be connected to the inner circumference of the casing 100 to support the casing 100. The first side 401 is spaced apart from the inner circumference of the housing 100 by a distance D5, so that the blood F2 flowing along the proximal plate 412 is less likely to adhere to the inner circumference of the housing 100 when it transitions to the distal plate 411. This allows more blood F2 to be introduced into the impeller 220 by the distal plate 411, and then the rectifying channel 404 guides most of the blood into the impeller 220 for driving the impeller 220, thereby increasing the blood flow driven by the impeller 220 and improving the blood pumping efficiency.

[0117] Furthermore, the first side 401 extends linearly in the axial direction, so that the rectifying plate 410 obtains a larger rectifying surface. Furthermore, the axial length of the first side 401 is greater than the axial length of the second side 402. Specifically, the first side 401 has a fourth axial length L4, and the second side 402 has a fifth axial length L5, i.e., L4>L5. This arrangement allows the distal plate 411 to extend longer than the proximal plate 412, resulting in less contact between the blood guided by the proximal plate 412 and the inner circumferential surface of the housing 100, thereby directing more blood toward the distal plate 411, thereby increasing the amount of blood guided by the distal plate 411 toward the impeller 220.

[0118] Since the second side 402 of the proximal plate 412 protrudes radially relative to the first side 401 of the distal plate 411, a transition step is formed at the junction of the second side 402 and the first side 401. Therefore, a rounded corner 403 is optionally provided at the junction of the second side 402 and the first side 401 to avoid a narrow sharp corner at the junction. This not only prevents blood cell loss due to blood collision, but also facilitates the proximal plate 412 to guide blood toward the distal plate 411.

[0119] Referring to Figures 17, 22, and 23, in one embodiment, the rectifying plate 410 has an incoming flow end surface 413 and a outgoing flow end surface 414. The incoming flow end surface 413 and the outgoing flow end surface 414 are located at opposite ends of the rectifying plate 410, with the outgoing flow end surface 414 facing the impeller 220 and the incoming flow end surface 413 facing away from the impeller 220. When blood enters the rectifying device 400, a portion of the blood F1 first contacts the incoming flow end surface 413 of the rectifying plate 410. The incoming flow end surface 413 then divides the blood into two blood flows F2, each flowing toward the rectifying channels 404 on either side of the rectifying plate 410. The blood flows F2 then flow along the rectifying channels 404. When they reach the outlets of the rectifying channels 404, the blood flows F2 from the two adjacent rectifying channels 404 merge at the outgoing flow end surface 414 of the rectifying plate 410 to form a blood flow F3.

[0120] In view of this, optionally, at least one of the flow-incoming end face 413 and the flow-delivery end face 414 is arranged in an arc shape from one plate surface of the rectifier plate 410 to the other plate surface. Specifically, the contours of the flow-incoming end face 413 and the flow-delivery end face 414 along the thickness direction of the rectifier plate 410 are semicircular, and the center O1 of the arc where the flow-incoming end face 413 is located is located on the bisector of the thickness of the rectifier plate 410, so that the two sides of the flow-incoming end face 413 can be smoothly connected with the two plate surfaces of the rectifier plate 410. Similarly, the center O2 of the arc where the flow-delivery end face 414 is located is also located on the bisector of the thickness of the rectifier plate 410, and the two sides of the flow-delivery end face 414 can also be smoothly connected with the two plate surfaces of the rectifier plate 410. Such an arrangement can make the flow-incoming end face 413 or the flow-delivery end face 414 smoother, thereby reducing the resistance of the flow-incoming end face 413 or the flow-delivery end face 414 to the fluid.

[0121] Taking the incident flow end surface 413 as an example, when blood enters the rectifier 400, blood F1 first contacts the incident flow end surface 413 of the rectifier plate 410. Guided by the arc-shaped incident flow end surface 413, it is then split into two blood flows F2 along the arc direction of the incident flow end surface 413. The two blood flows F2 flow into the rectifier channels 404 on either side of the rectifier plate 410, respectively. This effectively reduces the obstruction of the incident flow end surface 413 on the blood, reduces the kinetic energy loss of the blood upon entering the rectifier 400, and improves the blood pumping efficiency. Similarly, when blood flows F2 from two adjacent rectifier channels 404 are discharged, guided by the arc-shaped delivery end surface 414, the two blood flows F2 gradually fill and converge along the arc direction of the delivery end surface 414 into the distal space of the rectifier plate 410, thereby merging into blood flow F3. This relatively improves the smoothness of the blood flow after leaving the rectifier plate 410.

[0122] Referring to Figures 21 to 23 , in one embodiment, the thickness H of the rectifying plates 410 gradually increases along the direction from the motor 210 to the impeller 220. Consequently, the space between the two rectifying plates 410 in the rectifying section 520 gradually decreases along the direction from the motor 210 to the impeller 220, forming a rectifying channel 404 for pressurizing the blood. In other words, the width of the rectifying channel 404 gradually narrows along the direction from the motor 210 to the impeller 220. This allows the rectifying channel 404 to pre-pressurize the blood flow F2 before directing it to the impeller 220. In other words, the blood is pre-pressurized within the rectifying section 520 through the rectifying channel 404, and then further pressurized by the impeller 220 after flowing into the pressurizing section 530. Thus, compared to simply increasing the pressure through the impeller 220, by gradually increasing the pressure of the blood in the rectifying section 520 and the pressurizing section 530, the blood can be pressurized to a higher pressure, thereby improving the blood discharge efficiency. In other words, this arrangement improves the blood pumping efficiency of the blood pump 10.

[0123] Referring to Figure 21 , in another embodiment, the distal ends 12b of the plurality of rectifier plates 410 are all curved toward the same side along the circumference of the motor 210, and the curvature is aligned with the rotational direction of the impeller 220. Thus, as the blood flows from the proximal end to the distal end along the rectifier plates 410, an initial force aligned with the rotational direction of the impeller 220 is gradually applied. This arrangement improves the ease with which the impeller 220 can move the blood, thereby reducing the resistance to blood flow caused by the impeller 220 and improving the pumping efficiency of the blood pump 10. The curvature of the distal ends of the rectifier plates 410 is shown as S in Figure 21 .

[0124] Referring to Figures 16 to 18 , in one embodiment, the rectifying device 400 further includes a fixing ring 420 circumscribing the outer circumference of the rectifying plate 410 . The fixing ring 420 is fixedly connected to the casing 100 , and at least a portion of the inner wall of the fixing ring 420 is fixedly connected to the rectifying plate 410 to support the casing 100 . The fixing ring 420 in Figures 16 to 18 has the same structure as the fixing ring 420 shown in Figure 6 . In other words, the rectifying plate 410 in this embodiment can serve as the support member 410 shown in Figure 6 to support the fixing ring 420 .

[0125] Specifically, the fixing ring 420 surrounds the outer periphery of the proximal plate 412 of the rectifier plate 410; the inner wall surface of the fixing ring 420 is spaced apart from the outer periphery of the shaft support seat 211, and at least part of the inner wall surface of the fixing ring 420 is fixedly connected to the proximal plate 412 of the rectifier plate 410, so that the motor 210 supports and fixes the fixing ring 420 through the rectifier plate 410, and then supports the housing 100 through the fixing ring 420, thereby constructing a stable blood flow channel 500 between the housing 100 and the drive unit 200.

[0126] Referring to Figures 16, 17, and 20, in one embodiment, the casing 100 includes an inlet pipe 110 and a connecting pipe 120. The inlet pipe 110 and the connecting pipe 120 are respectively connected to the ends of the fixing ring 420 and are coaxially arranged with the fixing ring 420, so that the fixing ring 420 forms the middle portion of the casing 100. Coaxiality means that the central axes of the inlet pipe 110, the fixing ring 420, and the connecting pipe 120 are aligned. The inlet pipe 110, the fixing ring 420, and the connecting pipe 120 are sequentially connected along the direction from the motor 210 to the impeller 220 to form the casing 100, with the fixing ring 420 forming the middle portion of the casing 100. The inlet pipe 110 is provided with a liquid inlet 111, and the connecting pipe 120 is provided with a liquid outlet 122.

[0127] During assembly, the inlet pipe 110 of the casing 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 420; then the connecting pipe 120 of the casing 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 420. In this way, the casing 100 and the motor 210 are connected and fixed, which improves the convenience of assembly.

[0128] Referring to Figures 16 and 17 , in one embodiment, the inlet pipe 110, similar to the embodiments shown in Figures 6 to 9 , 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 the fixing ring 420; the reducing pipe 113 is sleeved around the periphery of the connection between the catheter 12 and the drive unit 200 and is fixedly connected to at least one of the drive unit 200 and the catheter 12. The plurality of connecting arms 114 are spaced apart along the circumference of the straight pipe 112, with a liquid inlet 111 formed between each two adjacent connecting arms 114.

[0129] Specifically, the straight tube 112 is arranged in a straight tube shape so that the inner circumference of the straight tube 112 forms a cylindrical surface, thereby reducing the fluid resistance of the blood flow channel. The reducer 113 is arranged in a conical shape. By sleeved on the outer circumference of the connection between the catheter 12 and the drive unit 200, the connection can be wrapped inside the reducer 113 to prevent the adhesive at the connection from being washed off by the blood. The reducer 113 has two interfaces, one of which is an interference fit with the distal outer circumference of the catheter 12, and the other is an interference fit with the proximal outer circumference of the drive unit 200. The straight tube 112, the reducer 113 and the connecting arm 114 can be formed as one piece.

[0130] Furthermore, the inner wall surfaces of the straight tube 112, the fixing ring 420 and the connecting tube 120 are flush along the axial direction to facilitate smooth blood flow. In addition, the outer wall surfaces of the straight tube 112, the fixing ring 420 and the connecting tube 120 are also flush along the axial direction. With this arrangement, the straight tube 112, the fixing ring 420 and the connecting tube 120 are assembled into a regular cylinder. With this arrangement, on the one hand, the outer circumferential surface of the housing 100 can be made smooth and regular, which can reduce damage to human tissue during the implantation of the blood pump 10; on the other hand, the inner circumferential surface of the housing 100 is also relatively smooth and regular, which can reduce the resistance of the blood flow channel 500 to the fluid, reduce the kinetic energy loss of blood circulating in the blood flow channel 500, improve blood pumping efficiency, and reduce blood cell damage.

[0131] Please refer to Figures 16 and 17. In one embodiment, the connecting tube 120 is provided with a first insertion portion 121 (see Figure 12), and the compensating tube 310 is provided with a second insertion portion 311 (see Figure 11). The first insertion portion 121 and the second insertion portion 311 are plugged into each other to connect the blood flow channel 500 in the housing 100 with the inner cavity of the compensating tube 310.

[0132] This fixing ring 420 is similar to the fixing ring 420 shown in FIG11 , and also includes a seventh insertion portion 421 and an eighth insertion portion 422. The seventh insertion portion 421 is pluggable with the fifth insertion portion 123 of the connecting tube 120, while the eighth insertion portion 422 is pluggable with the sixth insertion portion 116 of the inlet tube 110. Thus, the fixing ring 420 is pluggable with the connecting tube 120 and the inlet tube 110, respectively, to form the housing 100.

[0133] As shown in FIG16 , the compensating tube 310 shown in FIG16 can also have a first axial length L1, similar to the compensating tube 310 shown in FIG6 . The first axial length L1 is greater than or equal to 20 mm and less than or equal to 35 mm, that is, 20 mm ≤ L1 ≤ 35 mm. The structure of the compensating tube 310 described in this embodiment, as well as the connection and matching method between the compensating tube 310 and the housing 100, can be configured with reference to the embodiments of the compensating tube 310 described in the embodiments shown in FIG5 to FIG14 , and will not be further described here.

[0134] 15 and 16 , the cannula assembly 300 further includes an outlet tube 320, with a drainage port 321 disposed on the outlet tube 320. A fourth insertion portion 312 is disposed at the distal end of the compensating tube 310, and a third insertion portion 322 is disposed at the proximal end of the outlet tube 320. The fourth insertion portion 312 engages with the third insertion portion 322 to connect the inner lumens of the compensating tube 310 with those of the outlet tube 320, thereby delivering blood to the outlet tube 320 and discharging it into the pulmonary artery through the drainage port 321.

[0135] Referring to Figures 16 and 17 , in one embodiment, a flushing channel 201 is provided within the motor body 213. The shaft support 211 defines a drainage cavity 202 and an axial hole 203 communicating with the drainage cavity 202. The drainage cavity 202 communicates with the flushing channel 201. The motor shaft 212 extends from the distal end of the motor body 213 and sequentially passes through the drainage cavity 202 and axial hole 203 of the shaft support 211 to connect to the impeller 220. It is easy to understand that the flow path of the flushing liquid can be roughly the same as the extension distribution direction of the motor shaft 212, that is, the flushing liquid can flow into the drainage chamber 202 through the flushing channel 201, and flow out from the shaft hole 203 of the drainage chamber 202 to the gap between the shaft support seat 211 and the impeller 220, so that the flushing liquid can wash away the blood between the end of the shaft support seat 211 and the end of the impeller 220, so as to reduce the probability of blood staying in the gap between the shaft support seat 211 and the impeller 220 to form a thrombus.

[0136] Furthermore, the diameter of the drainage chamber 202 gradually decreases in the direction from the motor 210 to the impeller 220, so that the drainage chamber 202 can guide the flushing liquid from the flushing channel 201 to the axial hole 203, and in the process of the flushing liquid flowing from the proximal end to the distal end in the drainage chamber 202, the flushing liquid is gradually squeezed to increase the hydraulic pressure, so that the flushing liquid can discharge the axial hole 203 outward, while the blood in the blood flow channel 500 is difficult to enter the drainage chamber 202 from the axial hole 203, thereby avoiding the occurrence of thrombosis in the axial hole 203 and improving the anti-thrombosis effect.

[0137] In one embodiment, the blood pump also includes a catheter 12, in which a flushing liquid pipeline is provided for circulating flushing liquid (not shown in the figure, the same below). The flushing liquid pipeline is connected to the flushing channel 201 in the motor 210 to continuously provide flushing liquid to the flushing channel 201, thereby continuously flushing the gap between the shaft support seat 211 and the impeller 220.

[0138] Please refer to Figures 6 and 15. In one embodiment, the distal end of the catheter 12 is connected to the drive unit 200. The proximal end of the housing 100 can be placed on the periphery of the connection between the catheter 12 and the drive unit 200 to wrap the connection inside, reduce the scouring of the connection by blood, and prevent the adhesive at the connection from loosening. In conjunction with Figure 3, the catheter 12 can also have a proximal portion 12a, a distal portion 12b, and a bend 12c. The bend 12c is located between the proximal portion 12a and the distal portion 12b and is adjacent to the distal portion 12b. The bend 12c is preformed into a bend shape so that the shape of the bend 12c is adapted to the anatomical shape of the first connection point or the second connection point of the right atrium 22. For details, please refer to the implementation methods mentioned above and the embodiment shown in Figure 3, which will not be repeated here.

[0139] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned 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.

[0140] The above-described embodiments merely represent several implementation methods of the present application. 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 a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A blood pump, characterized in that: The blood pump comprises: Shell; A drive unit, wherein the drive unit is disposed inside the housing, and a proximal end of the housing is fixedly connected to a proximal end of the drive unit or a catheter of the blood pump; an inner circumferential surface of the housing and the drive unit are spaced to form a flow gap; and A sleeve assembly, the sleeve assembly comprising a compensation tube, the compensation tube having elasticity, the compensation tube being fixedly connected to the distal end of the sleeve shell, the inner cavity of the compensation tube being connected to the flow gap to form a blood flow channel; The proximal end of the housing is provided with a first opening, the distal end of the sleeve assembly is provided with a second opening, and the second opening is communicated with the first opening through the blood flow channel.

2. The blood pump according to claim 1, characterized in that The blood pump also has at least one of the following features: The compensating tube has a first axial length, which is greater than or equal to 20 mm and less than or equal to 35 mm; The compensating tube has a first axial length, the casing has a second axial length, and a ratio of the first axial length to the second axial length is greater than or equal to 0.7 and less than or equal to 1.3; The compensating tube includes an inner film, an outer film, and an elastic coil arranged between the inner film and the outer film.

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

4. The blood pump according to claim 1, characterized in that The casing has a distal pipe opening 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 has a distal point farthest from the catheter, the distal point is located in the casing and does not exceed the distal pipe opening, so that the impeller does not extend into the compensation tube; the distal point and the end faces of the distal pipe opening are both on a first plane, which is a plane perpendicular to the axis of the drive unit.

5. The blood pump according to claim 1, characterized in that A first insertion portion is provided at the distal end of the sleeve, and a second insertion portion is provided at the proximal end of the compensation tube. The second insertion portion is sleeved on the outer circumferential surface of the first insertion portion, and an overlapping area between the second insertion portion and the first insertion portion has a third axial length; the compensation tube has a first axial length, and a ratio of the third axial length to the first axial length is greater than or equal to 1 / 2 and less than or equal to 2 / 3.

6. The blood pump according to claim 1, characterized in that The driving unit includes a motor and an impeller connected to the motor; wherein the maximum outer diameter of the motor is a first diameter, the outer diameter of the impeller is a second diameter, the inner diameter of the casing is a third diameter, the third diameter is greater than the second diameter, and the second diameter is greater than the first diameter.

7. The blood pump according to claim 1, characterized in that The casing comprises an inlet pipe, a fixing ring and a connecting pipe, wherein the inlet pipe and the connecting pipe are respectively connected to two ends of the fixing ring; wherein the inlet pipe is provided with the first opening, and the end of the inlet pipe away from the fixing ring is fixedly connected to the proximal end of the driving unit or the catheter; 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 driving unit through a support member.

8. The blood pump according to claim 7, characterized in that The inlet pipe includes a straight pipe, a reducer and a plurality of connecting arms connecting the straight pipe and the reducer; wherein the straight pipe is connected to the fixing ring; the reducer is sleeved on the outer circumference of the connection between the conduit and the driving unit, and is fixedly connected to at least one of the driving 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.

9. The blood pump according to claim 8, characterized in that The inner wall surfaces of the straight tube, the fixing ring and the connecting tube are flush along the axial direction of the straight tube, and the outer wall surfaces of the straight tube, the fixing ring and the connecting tube are also flush along the axial direction of the straight tube; 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 reducer; the second connecting portion is located on the outer circumferential surface of the reducer, and a notch groove is formed between two adjacent second connecting portions, and the notch groove is connected to the first opening along the axial direction of the inlet pipe.

10. The blood pump according to claim 1, characterized in that The distal end of the blood pump can sequentially pass through the right atrium, the right ventricle and the pulmonary valve to extend into the pulmonary artery, so that the first opening is in the right ventricle and the second opening is in the pulmonary artery; The blood pump includes the catheter, which has a proximal part, a distal part and a bending portion, wherein the bending portion is located between the proximal part and the distal part and is adjacent to the distal part, and the bending portion is preformed into a bending shape so that the shape of the bending portion is adapted to the anatomical shape of a first connecting point or a second connecting point of the right atrium; wherein the first connecting point is the connecting point between the right atrium and the inferior vena cava; and the second connecting point is the connecting point between the right atrium and the superior vena cava.

11. A blood pump, characterized in that: The blood pump comprises: A casing, wherein the casing is provided with a liquid inlet and a liquid outlet; A driving unit, wherein the driving unit is arranged inside the casing, and the proximal end of the casing is fixedly connected to the proximal end of the driving unit or the catheter of the blood pump; a blood flow channel is formed between the inner circumferential surface of the casing and the driving unit, and the blood flow channel connects the liquid inlet and the liquid outlet; wherein the driving unit includes a motor and an impeller connected to the motor; A sleeve assembly, wherein the sleeve assembly is provided with a liquid discharge port, the sleeve assembly includes a compensation tube, the compensation tube is elastic, the compensation tube is fixedly connected to and communicated with the distal end of the housing, so that the liquid discharge port is communicated with the liquid outlet of the housing through the inner cavity of the compensation tube; and A rectifying device is arranged in the blood flow channel, and the rectifying device can guide the blood to flow from the periphery of the motor to the impeller.

12. The blood pump according to claim 11, characterized in that The motor comprises a motor body and a shaft support seat connected to the distal end of the motor body; the blood flow channel comprises a drainage section, a rectification section and a boost section which are connected in sequence; wherein the drainage section is located between the outer circumference of the motor body and the inner circumference of the casing, and is connected to the liquid inlet; the rectification section is located between the outer circumference of the shaft support seat and the inner circumference of the casing; the boost section is located between the impeller and the inner circumference of the casing, and is connected to the liquid outlet; the rectification device is arranged in the rectification section, and is fixedly connected to the shaft support seat.

13. The blood pump according to claim 12, characterized in that The outer diameter of the shaft support seat is gradually reduced in the direction from the motor to the impeller, so that the outer peripheral surface of the shaft support seat forms a conical guide surface; the rectifier device includes a plurality of rectifier plates, and the plurality of rectifier plates are arranged on the conical guide surface at intervals along the circumference of the shaft support seat, and the outer side edge of the rectifier plate away from the conical guide surface is parallel to the motor shaft.

14. The blood pump according to claim 11, characterized in that The rectifier device includes a plurality of rectifier plates, which are fixed on the outer peripheral surface of the motor and arranged at intervals along the circumference of the motor; the plurality of rectifier plates extend along the axial direction of the motor to form a linearly extending rectifier channel between two adjacent rectifier plates.

15. The blood pump according to claim 14, characterized in that The rectifier plate includes a proximal plate body and a distal plate body, and the proximal plate body and the distal plate body are arranged and connected along the axial direction of the motor; wherein the distal plate body has a first side edge away from the outer circumferential surface of the motor; the proximal plate body has a second side edge away from the outer circumferential surface of the motor, and at least one of the second side edge and the first side edge is fixedly connected to the inner circumferential surface of the casing.

16. The blood pump according to claim 15, characterized in that The first side is spaced apart from the inner circumference of the casing, and the second side is fixedly connected to the inner circumference of the casing; wherein the fourth axial length of the first side is greater than the fifth axial length of the second side; or a chamfer is provided at the connection between the first side and the second side.

17. The blood pump according to claim 14, characterized in that The blood pump also has at least one of the following solutions: The rectifying plate has a flow-incoming end face and a flow-out end face, the flow-incoming end face and the flow-out end face are respectively located at two ends of the rectifying plate, the flow-incoming end face faces away from the impeller, and the flow-out end face faces the impeller; at least one of the flow-incoming end face and the flow-out end face is arranged in an arc shape from one plate surface of the rectifying plate to the other plate surface, and the center of the arc is located on the bisector of the thickness of the rectifying plate; The thickness of the rectifier plate gradually increases in the direction from the motor to the impeller; The distal end portions of the plurality of rectifier plates are all bent toward the same side along the circumference of the motor, and the bending direction is consistent with the rotation direction of the impeller.

18. The blood pump according to claim 14, characterized in that The rectifying device further comprises a fixing ring, which surrounds the outer periphery of the plurality of rectifying plates, is fixedly connected to the casing, and at least a part of the inner wall surface of the fixing ring is fixedly connected to the outer side edge of the rectifying plate to support the casing; The casing comprises an inlet pipe and a connecting pipe; the inlet pipe and the connecting pipe are respectively connected to the two ends of the fixing ring and are coaxially arranged with the fixing ring so that the fixing ring constitutes the middle part of the casing; wherein the proximal end of the inlet pipe is provided with the liquid inlet, and the distal end of the connecting pipe is provided with the liquid outlet.

19. The blood pump according to claim 18, characterized in that The inlet pipe includes a straight pipe, a reducer and a plurality of connecting arms connecting the straight pipe and the reducer; wherein, The straight tube is connected to the fixing ring, and the inner wall surfaces of the straight tube, the fixing ring and the connecting tube are flush along the axial direction of the straight tube, and the outer wall surfaces of the straight tube, the fixing ring and the connecting tube are also flush along the axial direction of the straight tube; The reducer 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 tube, and a liquid inlet is formed between every two adjacent connecting arms.

20. The blood pump according to claim 11, characterized in that The distal end of the blood pump can sequentially pass through the right atrium, the right ventricle and the pulmonary valve to extend into the pulmonary artery, so that the liquid inlet is located in the right ventricle and the liquid outlet is located in the pulmonary artery; The blood pump includes the catheter, which has a proximal part, a distal part and a bending portion, wherein the bending portion is located between the proximal part and the distal part and is adjacent to the distal part, and the bending portion is preformed into a bending shape so that the shape of the bending portion is adapted to the anatomical shape of a first connecting point or a second connecting point of the right atrium; wherein the first connecting point is the connecting point between the right atrium and the inferior vena cava; and the second connecting point is the connecting point between the right atrium and the superior vena cava.

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