Blood pump

Abstract

Provided is a blood pump (1), comprising a pump body (11). The pump body (11) comprises a pump housing (100), a driving unit (200), and an insensitive ring (300). A liquid inlet (101) is provided at a proximal end of the pump housing (100), an opening at a distal end of the pump housing (100) is configured as a liquid outlet (102), and a central axis of the pump housing (100) passes through the liquid outlet (102). The driving unit (200) is fixedly connected to the proximal end of the pump housing (100), and the driving unit (200) can drive blood to flow from the liquid inlet (101) to the liquid outlet (102). An insensitive ring (300) is arranged along the circumference of the liquid outlet (102). The radial thickness of the insensitive ring (300) is greater than the pipe wall thickness of the pump housing (100). The insensitive ring (300) is provided with an annular wall (310) extending in a circumferential direction thereof, and the center of a generating circle of an annular body where the annular wall (310) is located is located inside the insensitive ring (300).

Description

blood pump

[0001] This application claims priority to two Chinese patent applications, application number CN202311568122.6 and name “Blood Pump” filed with the China Patent Office on November 21, 2023, and application number CN202311861519.4 and name “Blood Pump” filed with the China Patent Office on December 29, 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 assist the right ventricle in pumping blood. The push path of this blood pump implantation is generally from the inferior vena cava or superior vena cava, through the right atrium, tricuspid valve, right ventricle, pulmonary valve and reach the pulmonary artery. This right ventricular push path has the characteristics of a short path, many bends, and complex internal tissues. Therefore, during the implantation process, the blood pump often needs to go through multiple turns to pass through the bend of the push path. However, when the distal part of the traditional blood pump turns and passes through the bend of the push path, it is very easy to collide or rub with the internal tissue on the push path, thereby damaging the internal tissue.

[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 reduce collision or friction with internal tissues during implantation to avoid damaging the internal tissues.

[0007] The present application provides a blood pump, which includes a pump body, and the pump body includes a pump casing, a drive unit and an insensitive ring. The proximal end of the pump casing is provided with a liquid inlet, and the distal end of the pump casing is open, so that the distal end opening of the pump casing is set as a liquid outlet, and the central axis of the pump casing passes through the liquid outlet. The drive unit is fixedly connected to the proximal end of the pump casing, and the drive unit can drive blood to flow from the liquid inlet to the liquid outlet. The insensitive ring is arranged along the circumference of the liquid outlet; the radial thickness of the insensitive ring is greater than the thickness of the tube wall of the pump casing; the insensitive ring is provided with an annular wall extending along its circumferential direction, and the center of the mother circle of the annular body where the annular wall is located is located inside the insensitive ring.

[0008] The present application also provides a blood pump, comprising a pump body, the pump body comprising a pump housing, a desensitizing ring, and a drive unit. The pump housing comprises a main section having a liquid inlet and a variable diameter section connected to the main section; the desensitizing ring is disposed at the distal end of the variable diameter section, the inner circumference of the desensitizing ring and the inner circumference of the variable diameter section jointly defining a liquid outlet; the distal end of the desensitizing ring is provided with a desensitizing wall, the desensitizing wall being located on a circular ring, the center of the parent circle of the circular ring being located within the desensitizing ring, the desensitizing wall extending along the circumference of the desensitizing ring, the radial width of the desensitizing wall along the radial direction of the pump housing being greater than the thickness of the tube wall of the pump housing. The drive unit comprises an impeller disposed within the pump housing, the impeller pointing toward the liquid outlet. The direction in which the impeller points toward the liquid outlet is referred to as a first direction, and the diameter of the liquid outlet gradually increases along the first direction, so that the liquid outlet has a flared shape.

[0009] 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

[0010] 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.

[0011] FIG1 is a schematic structural diagram of an embodiment of a blood pump of the present application.

[0012] FIG2 is a front view of the blood pump shown in FIG1 .

[0013] FIG3 is a cross-sectional view of the structure shown in FIG2 along line II.

[0014] FIG. 4 is a schematic diagram of a portion of the structure shown in FIG. 3 with dimensioning.

[0015] FIG5 is a schematic diagram of the exploded structure of the blood pump shown in FIG1 .

[0016] FIG6 is a schematic diagram of the blood flow direction when the pump body of the blood pump of the present application is placed in the pulmonary artery.

[0017] FIG. 7 is a schematic diagram showing the extension tube and the insensitive ring of the blood pump shown in FIG. 1 being connected as one.

[0018] FIG8 is a longitudinal sectional view of the structure shown in FIG7.

[0019] FIG9 is an enlarged view of the structure P1 shown in FIG8 .

[0020] FIG. 10 is a schematic diagram showing dimension markings of the structure shown in FIG. 9 .

[0021] FIG11 is a schematic structural diagram of another embodiment of the blood pump of the present application.

[0022] FIG12 is a schematic diagram of the internal structure of the blood pump shown in FIG11 .

[0023] FIG13 is a schematic structural diagram of another embodiment of the blood pump of the present application.

[0024] FIG14 is a front view of the blood pump shown in FIG13.

[0025] FIG15 is a cross-sectional view of the structure shown in FIG14 along line II.

[0026] FIG. 16 is a schematic diagram of a portion of the structure shown in FIG. 15 with dimension markings.

[0027] FIG17 is an enlarged view of the structure P2 shown in FIG16 .

[0028] FIG. 18 is a top view of the blood pump in FIG. 13 .

[0029] FIG19 is a schematic diagram of the structural decomposition of the blood pump shown in FIG13.

[0030] FIG20 is a schematic diagram showing the extension tube and the insensitive ring of the blood pump shown in FIG19 being connected as one.

[0031] FIG21 is a longitudinal sectional view of the structure shown in FIG20.

[0032] FIG22 is an enlarged view of structure P3 shown in FIG21 .

[0033] FIG23 is a schematic diagram showing the angles of tangent lines of a portion of the structure shown in FIG22 .

[0034] FIG24 is a schematic diagram showing the pump body of the blood pump of the present application being clamped and fixed by the pulmonary valve.

[0035] FIG25 is a schematic diagram of the blood pump of the present application being implanted into the pulmonary artery from the first blood pathway.

[0036] FIG26 is a schematic diagram of the blood pump of the present application being implanted into the pulmonary artery through the second blood pathway.

[0037] FIG. 27 is a schematic diagram showing the distal end of a blood pump in contact with the inner wall of a tissue in the prior art.

[0038] FIG28 is a schematic diagram showing the distal end of the blood pump of the present application in contact with the inner wall of the tissue. DETAILED DESCRIPTION

[0039] To make the above-mentioned objects, features, and advantages of the present application more clearly understood, the specific embodiments of the present application are described in detail below with reference to the accompanying drawings. The following description sets forth many specific details to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways than those described herein, and those skilled in the art can make similar improvements without violating the scope of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0040] In the description of this application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0041] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include at least one of such features. In the description of this application, if the term "plurality" appears, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0042] In this application, unless otherwise specified or limited, the terms "mounted," "connected," "connected," "fixed," etc., should be interpreted broadly. For example, these terms may refer to fixed connections, removable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediary; and internal communication between two components or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0043] In this application, unless otherwise expressly specified or limited, when a first feature is described as being "above" or "below" a second feature, or similar descriptions, this may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is described as being "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is described as being "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0044] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only embodiment.

[0045] In the related art, a blood pump has emerged that can assist the right ventricle in pumping blood. The delivery path for this blood pump implantation typically begins at the inferior or superior vena cava, passes through the right atrium, tricuspid valve, right ventricle, pulmonary valve, and finally reaches the pulmonary artery. This delivery path to the right ventricle is characterized by a short path, numerous bends, and complex internal structures. Therefore, during implantation, the blood pump often needs to make multiple turns to navigate the bends in the delivery path.

[0046] Referring to FIG. 27 , conventional blood pumps typically have multiple side openings 30 on their distal sidewalls. These side openings 30 serve as liquid discharge outlets. These side openings 30 are spaced apart circumferentially, with connecting posts 31 formed between adjacent side openings 30. These connecting posts 31 are slender and made of metal, resulting in relatively sharp edges. As the right ventricular delivery pathway is short and winding, the distal end of the blood pump often undergoes significant deflection when it turns through a narrow bend in the delivery pathway during implantation. This makes it very easy for the distal side of the blood pump to come into contact with the tissue walls at the bend, potentially dipping into the side openings 30 along the blood pump's radial direction. Subsequently, as the blood pump continues to be advanced in the direction indicated by T in FIG. 27 , the connecting posts 31 on either side of the side openings 30 could scrape against the tissue walls 40 that have sunk into the side openings 30, causing damage to the patient's internal tissue.

[0047] Referring to Figure 28, in order to solve the above problems, the present application provides a blood pump 10, which includes a pump body 11 and a catheter 12. The blood pump 10 can reduce the collision or friction between the pump body 11 and the inner wall of the tissue 40 during the implantation process to avoid damaging the patient's internal tissue. The blood pump 10 is mainly used as a right ventricular assist pump; 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 1 to 3 , in one embodiment of a blood pump 10 of the present application, the blood pump 10 includes a pump body 11, which includes a pump housing 100 and a drive unit 200. A liquid inlet 101 is provided at the proximal end of the pump housing 100, and the distal end of the pump housing 100 is open, so that the distal end of the pump housing 100 is configured as a liquid outlet 102. The central axis M1M2 of the pump housing 100 passes through the liquid outlet 102. The drive unit 200 is fixedly coupled to the proximal end of the pump housing 100 and is capable of driving blood from the liquid inlet 101 to the liquid outlet 102.

[0049] By configuring the distal opening of the pump housing 100 as the liquid outlet 102, the distal sidewall of the pump housing 100 is free of openings. Consequently, during implantation of the blood pump 10, when the pump body 11 of the blood pump 10 turns and passes through a narrow bend in the delivery path, even if the distal sidewall of the pump body 11 abuts against the inner tissue wall at the bend, the inner tissue wall will not radially penetrate into the pump body 11. Compared to the sidewalls of the pump housing 100, the distal opening of the pump housing 100 is less likely to directly abut against the inner tissue wall. Therefore, configuring the distal opening of the pump housing 100 as the liquid outlet 102 reduces the risk of the inner tissue wall penetrating the liquid outlet 102. Furthermore, the larger flow area of ​​the liquid outlet 102 increases the amount of blood pumped.

[0050] Based on this, the present application also considers that the wall thickness of the pump housing 100 itself is generally thin, which can make the peripheral edge of the liquid outlet 102 of the pump housing 100 relatively sharp. As shown in FIG28 , during the implantation process of the blood pump 10, when the blood pump 10 is pushed in the direction indicated by T in FIG28 , the peripheral edge of the liquid outlet 102 of the pump housing 100 may also contact the inner wall of the tissue. Therefore, to prevent the liquid outlet 102 of the pump housing 100 from cutting the inner wall of the tissue, in the present application, the pump body 11 is further provided with a desensitizing ring 300. The desensitizing ring 300 is arranged along the peripheral edge of the liquid outlet 102. As shown in FIG3 and FIG4 , the radial thickness H1 of the desensitizing ring 300 is greater than the wall thickness H2 of the pump housing 100, that is, H1>H2. The desensitizing ring 300 is provided with an annular wall 310 extending along its circumference, and the center of the parent circle of the annular body of the annular wall 310 is located inside the desensitizing ring 300.

[0051] Specifically, by setting the radial thickness H1 of the insensitive ring 300 to be greater than the wall thickness H2 of the pump housing 100, the radial thickness of the insensitive ring 300 can be increased, thereby improving the insensitivity of the insensitive ring 300 and making it less sharp. Furthermore, a circular wall 310 extending along the circumferential direction is provided on the surface of the insensitive ring 300, so that the surface of the insensitive ring 300 can be made more rounded and smooth, and less likely to cut the inner wall of the tissue. The circular wall 310 is located on a corresponding annular body. The annular body refers to an annular structure formed by rotating a circle around an axis that does not intersect the circle. The circle is usually referred to as the mother circle of the annular body. For example, structures such as swimming rings, donuts, and hula hoops are all annular bodies. The insensitive ring 300 can be set as an annular body as a whole, so that the annular wall 310 is formed on the entire surface of the insensitive ring 300. Alternatively, the insensitive ring 300 itself is not a circular ring, but only a portion of the surface of the insensitive ring 300 is set as the circular wall 310. The circular ring where the circular wall 310 is located is a virtual circular ring for designing the shape of the circular wall 310.

[0052] Regardless of whether the annular body within which the annular wall 310 resides is the insensitive ring 300 itself or a virtual annular body, the center of the annular body's parent circle should be located within the insensitive ring 300, such that the annular wall 310 is convex outward relative to the interior of the insensitive ring 300, thereby making the circumference of the insensitive ring 300 relatively round and smooth. When the blood pump 10 is implanted in a patient, the distal end of the pump body 11 can contact the inner wall of the tissue through the insensitive ring 300. Because the annular wall 310 of the insensitive ring 300 is relatively round and smooth, it is less likely to scratch the inner wall of the tissue, thereby preventing damage to the patient's internal tissue.

[0053] The technical solution of the present application, by setting the distal opening of the pump housing 100 as the liquid outlet 102, can ensure that no opening is formed on the distal side wall of the pump housing 100. Therefore, during the implantation of the blood pump 10, when the pump body 11 of the blood pump 10 turns and passes through the narrow bend of the push path, even if the distal side wall of the pump body 11 abuts against the inner wall of the tissue at the bend, these inner walls of the tissue will not sink into the pump body 11 from the radial direction of the pump body 11. In addition, the present application also provides a desensitizing ring 300 on the periphery of the liquid outlet 102 of the pump housing 100. The radial thickness H1 of the desensitizing ring 300 is greater than the tube wall thickness H2 of the pump housing 100, and a circular wall 310 extending along its circumference is provided on the desensitizing ring 300. The center of the mother circle of the circular body where the circular wall 310 is located is located inside the desensitizing ring 300, so that the circular wall 310 is convex outward relative to the inside of the desensitizing ring 300, thereby making the circumference of the desensitizing ring 300 relatively round and smooth, avoiding the periphery of the liquid outlet 102 from being too sharp and not easy to scratch the inner wall of the tissue, thereby avoiding the distal end of the pump body 11 from scratching the patient's internal tissue.

[0054] 2 and 3 , when the blood pump 10 is operating, the drive unit 200 drives blood from the liquid inlet 101 into the pump housing 100. Within the pump housing 100, the blood continues to be driven by the drive unit 200, flowing along the axial direction of the drive unit 200 (i.e., the direction from M1 to M2) toward the liquid outlet 102. When the blood reaches the distal end of the pump housing 100, it can be discharged directly from the liquid outlet 102 along the axial direction of the drive unit 200. This prevents significant radial deflection of the blood from being discharged from the liquid outlet 102, thereby reducing kinetic energy loss during the blood discharge process.

[0055] As shown in Figures 3 and 7 to 9 , the distal end of the insensitive ring 300 is more likely to come into contact and rub against the inner wall of tissue. Therefore, in this embodiment, the annular wall 310 of the insensitive ring 300 includes at least a distal wall 311 located at the distal end of the insensitive ring 300. The distal wall 311 has a semicircular cross-section as measured by an axial plane passing through the central axis. Point O in Figure 9 represents the center of the circle encompassing the cross-section of the distal wall 311, i.e., the center of the parent circle of the annular body encompassing the distal wall 311.

[0056] Because the insensitive ring 300 has a radial thickness H1, the parent circle of the annular body containing the distal wall 311 can be a circle with the radial thickness H1 of the insensitive ring 300 as its diameter. Thus, a cross-section of the distal wall 311 taken along the axial plane is semicircular. This arrangement allows the distal wall 311 to form the distal end surface of the insensitive ring 300, with both sides of the distal wall 311 smoothly transitioning to the inner and outer circumferential surfaces of the pump housing 100, respectively. This prevents the insensitive ring 300 from injuring the tissue wall when its distal end contacts it, reducing the risk of blood pump 10 implantation.

[0057] Referring to Figures 3, 8, and 9, the annular wall 310 optionally further includes an outer wall 312 located outside the insensitive ring 300. The outer wall 312 has an arc-shaped cross-section as measured by the axial plane. The outer wall 312 smoothly connects the distal wall 311 to the outer circumference of the pump housing 100. The outer wall 312 forms a portion of the outer surface of the insensitive ring 300, further rounding the outer surface. This makes it less likely that the outer surface of the insensitive ring 300 will injure the inner tissue wall when it contacts it, thereby reducing the risk of blood pump 10 implantation.

[0058] Furthermore, the annular wall 310 includes an inner wall 313 located inside the insensitive ring 300. The cross-section of the inner wall 313, as measured by the axial plane, is arc-shaped. The inner wall 313 smoothly connects the distal wall 311 to the inner circumferential surface of the pump housing 100. The inner wall 313 forms a portion of the inner surface of the insensitive ring 300, making the inner surface of the insensitive ring 300 more rounded. When blood is discharged from the liquid outlet 102, a portion of the blood contacts the inner wall 313. This reduces the risk of damaging blood cells, thereby improving the safety of the blood pump 10.

[0059] Referring to Figures 7 to 9, in one embodiment, the insensitive ring 300 is configured as a circular ring body, so that the insensitive ring 300 itself serves as the circular ring body where the circular ring wall 310 is located; and the two cross-sections S1 and S2 of the insensitive ring 300 cut by any one of the axial planes are symmetrical about the central axis M1M2. In other words, one of the cross-sections S1 or S2 of the insensitive ring 300 can serve as the mother circle of the circular ring body, and the center of the mother circle is point O. In this way, the two cross-sections of the insensitive ring 300 cut by any one of the axial planes will be symmetrical about the central axis M1M2. This arrangement can make the entire insensitive ring 300 relatively smooth along its circumferential direction, without forming sharp edges, greatly reducing the risk of the pump housing 100 damaging the inner wall of the tissue.

[0060] 1 to 3 , the insensitive ring 300 can be configured as an integral structure with the pump housing 100, or can be configured as a separate structure with the pump housing 100. The specific design can be combined with the specific structure of the pump housing 100. Optionally, in one embodiment, the pump housing 100 includes a shell tube 110 fixedly connected to the drive unit 200, and an extension tube 120 fixedly connected to the shell tube 110; wherein the shell tube 110 is provided with a liquid inlet 101; the proximal end of the extension tube 120 is fixedly connected to the shell tube 110, and the distal end of the extension tube 120 is provided with a distal opening for forming a liquid outlet 102. The insensitive ring 300 is connected to the periphery of the distal opening, and the insensitive ring 300 constitutes the farthest end of the blood pump 10.

[0061] Referring to Figures 3 and 5 , the shell tube 110 and the extension tube 120 are two separately molded components. The insensitive ring 300 can be integrally molded with the extension tube 120 to reduce the number of parts and simplify processing and assembly steps. Of course, in other embodiments, the insensitive ring 300 can also be manufactured separately and then fixedly attached to the extension tube 120. Specifically, in this embodiment, the insensitive ring 300 is integrally molded with the extension tube 120.

[0062] In one embodiment, at least one of the extension tube 120 and the insensitive ring 300 is configured as an elastic structure. For example, the insensitive ring 300 is configured as an elastic structure, which allows the insensitive ring 300 to be elastic. When the insensitive ring 300 contacts the inner wall of tissue during implantation of the blood pump 10, the insensitive ring 300 can elastically deform to buffer the force exerted by the insensitive ring 300 on the inner wall of the tissue.

[0063] Similarly, the extension tube 120 can also be configured as an elastic structure. During the implantation of the blood pump 10, when the insensitive ring 300 contacts the inner wall of the tissue, the force between the insensitive ring 300 and the inner wall of the tissue will be transmitted to the extension tube 120. The elastic deformation of the extension tube 120 can also buffer the force exerted by the insensitive ring 300 on the inner wall of the tissue. Given that the insensitive ring 300 and the extension tube 120 are integrally formed, in this embodiment, the insensitive ring 300 and the extension tube 120 are both elastic structures. The elastic structure refers to a structure supported by an elastic material, which can be a TPU material. Of course, in other embodiments, the insensitive ring 300 and the extension tube 120 can also be made of metal materials, so that the insensitive ring 300 and the extension tube 120 have rigidity.

[0064] Referring to Figures 3 and 8, in one embodiment, given that the radial thickness H1 of the insensitive ring 300 is greater than the wall thickness H2 of the pump casing 100, in order to avoid the formation of a relatively sharp transition step at the connection between the pump casing 100 and the insensitive ring 300, the extension tube 120 optionally includes a connecting section 121 fixedly connected to the casing tube 110, and a transition section 122 connecting the connecting section 121 and the insensitive ring 300. The inner circumference of the connecting tube 113 is axially connected and flush with the inner circumference of the casing tube 110; and the inner and outer circumferences of the connecting tube 113 are axially connected and flush with the outer circumference of the casing tube 110. The pump casing 100 gradually transitions to the insensitive ring 300 through the transition section 122, so that the connection between the pump casing 100 and the insensitive ring 300 is relatively smooth and less likely to form a sharp transition step.

[0065] Referring to Figures 3 and 10 , the connecting section 121 further comprises a first inner diameter A1, and the insensitive ring 300 comprises a second inner diameter B1. The second inner diameter B1 is the minimum inner diameter of the insensitive ring 300 and is smaller than the first inner diameter A1, i.e., B1 < A1. This allows the liquid outlet 102 to be a constricted opening relative to the inner lumen of the connecting section 121. When blood is discharged from the liquid outlet 102, it is compressed, increasing its pressure. This allows the blood to gain greater kinetic potential energy after exiting the liquid outlet 102 into the pulmonary artery 26, thereby increasing the blood flow rate within the pulmonary artery 26.

[0066] Also referring to Figures 3 and 10 , optionally, the connecting section 121 has a first outer diameter A2, and the insensitive ring 300 has a second outer diameter B2. Second outer diameter B2 is the maximum outer diameter of the insensitive ring 300 and is smaller than the first outer diameter A2, i.e., B2 < A2. Because the insensitive ring 300 forms the distal end of the pump body 11, setting the second outer diameter B2 smaller than the first outer diameter A2 is equivalent to reducing the diameter of the distal end of the pump body 11. This reduces the resistance of the distal end of the pump body 11 through the various bends in the delivery path, allowing the pump body 11 to be more smoothly implanted in the patient.

[0067] Referring to Figures 8 to 10 , in one embodiment, the transition section 122 has an inner transition surface 122b and an outer transition surface 122a. The outer transition surface 122a connects the outer circumference of the connecting section 121 and the outer sidewall 312 of the insensitive ring 300, while the inner transition surface 122b connects the inner circumference of the connecting section 121 and the inner sidewall 313 of the insensitive ring 300. The transition section 122 has a third inner diameter C1, which is the diameter of the inner transition surface 122b. This third inner diameter C1 gradually decreases from the connecting section 121 to the insensitive ring 300. This allows the inner transition surface 122b to smoothly connect the inner circumference of the connecting section 121 and the inner sidewall 313 of the insensitive ring 300, resulting in a smoother inner circumference of the pump housing 100, thereby reducing blood flow resistance and minimizing blood cell damage.

[0068] Referring also to Figures 8 to 10 , the transition section 122 further comprises a third outer diameter C2, which is the diameter of the outer transition surface 122a. The third outer diameter C2 gradually decreases and then increases along the direction from the connecting section 121 to the insensitive ring 300. This allows the outer transition surface 122a to smoothly connect the outer circumference of the connecting section 121 and the outer sidewall 312 of the insensitive ring 300, making the outer circumference of the pump housing 100 smoother. This avoids the formation of sharp transition steps on the outer circumference of the pump housing 100, thereby reducing damage from collision with the inner wall of tissue.

[0069] Because the third outer diameter C2 gradually decreases and then increases along the direction from the connecting section 121 to the insensitive ring 300, an annular recess 105 is formed on the outer side of the transition section 122. When the insensitive ring 300 is configured as an elastic structure, the presence of the annular recess 105 can enhance the amplitude of the elastic deformation of the insensitive ring 300 in the axial direction, further buffering the reaction force of the insensitive ring 300 on the inner wall of the tissue.

[0070] In the embodiment of the blood pump 10 shown in Figures 11 and 12, since the transition section 122 forms the transition portion of the extension tube 120, the transition section 122 is recessed relative to the connecting section 121 and the insensitive ring 300 toward the central axis M1M2 of the pump housing 100, making it relatively less likely for the transition section 122 to come into surface contact with the inner wall of the tissue. Therefore, a plurality of through holes 104 are optionally provided through the sidewall of the transition section 122, with the plurality of through holes 104 spaced apart along the circumference of the transition section 122. A portion of the blood within the pump housing 100 can be discharged directly axially from the liquid outlet 102, while a smaller portion can be discharged radially from the through holes 104. This can increase the amount of blood pumped by the blood pump 10.

[0071] Because the multiple through-holes 104 are spaced apart, partition walls 108 are formed between adjacent through-holes 104. To prevent the partition walls 108 from forming a prismatic shape, the through-holes 104 optionally have a second length L2 extending along the circumference of the extension tube 120, and the partition walls 108 have a third length L3 extending along the circumference of the extension tube 120. The third length L3 is greater than or equal to the second length L2, i.e., L3 ≥ L2. This arrangement allows the partition walls to extend longer along the circumference of the extension tube 120, providing a larger surface area and preventing them from forming a prismatic shape. This prevents the inner tissue wall from being damaged even if it contacts the through-holes 104 or partition walls 108.

[0072] Regarding the drive unit 200 of the blood pump 10, the drive unit 200 includes a motor 210 and an impeller 220 connected to the motor 210. The motor 210 is capable of driving the impeller 220 to rotate, so that the impeller 220 drives blood to flow from the liquid inlet 101 into the pump housing 100 and be discharged from the liquid outlet 102 of the pump housing 100. In the present application, there are two ways to assemble the drive unit 200 and the pump housing 100. For example, referring to Figures 11 and 12, in one embodiment, only the impeller 220 of the drive unit 200 is disposed inside the pump housing 100, the distal end of the motor 210 is fixedly connected to the proximal end of the pump housing 100, and the motor shaft of the motor 210 extends into the pump housing 100 to be fixedly connected to the impeller 220. In this way, the first length of the pump body 11 is close to the sum of the length of the motor 210 and the length of the pump housing 100.

[0073] In the embodiment shown in Figures 1 to 6 , the motor 210 and impeller 220 of the drive unit 200 are both disposed within the interior of the pump housing 100. A blood flow channel 103 is formed between the motor 210 and the inner wall of the pump housing 100. The blood flow channel 103 connects the liquid outlet 102 with the liquid inlet 101. The proximal end of the motor 210 is affixed to the proximal end of the pump housing 100. Specifically, the proximal end of the pump housing 100 is affixed to the proximal end of the motor 210, and the inner wall of the pump housing 100 is spaced apart from the outer circumference of the motor 210 to form a portion of the blood flow channel 103. As such, the first length L1 of the pump body 11 is close to the length of the pump housing 100, thereby ensuring that the first length L1 of the pump body 11 is relatively short. This ensures that the first length L1 of the pump body 11 can accommodate both the propulsion path of the right ventricle 24 and the physiological structure of the pulmonary artery 26, thereby facilitating better implantation within the pulmonary artery 26.

[0074] Referring to Figures 3, 6, and 7, the proximal end of the pump housing 100 is optionally provided with a plurality of connecting arms 107, with a liquid inlet 101 spaced apart between each two adjacent connecting arms 107. The proximal end of the outer circumference of the motor 210 is provided with a plurality of fixing portions 214, with an inlet slot 106 spaced apart between each two adjacent fixing portions 214. The inlet slot 106 faces the proximal end of the catheter 12. The plurality of fixing portions 214 are respectively connected to the plurality of connecting arms 107 in a one-to-one correspondence, such that the inlet slots 106 and the proximal ends of the liquid inlet 101 are butt-jointed and connected. When the pump body 11 is placed in the pulmonary artery 26, the liquid inlet 101 of the pump body 11 is adjacent to the pulmonary valve 25, and the inlet slot 106 faces the central region of the pulmonary valve 25, through which the catheter 12 passes. When the blood pump 10 is working, after the blood in the right ventricle 24 passes through the pulmonary valve 25, a portion of the blood F2 is radially sucked into the liquid inlet 101 from the circumference of the pump body 11, and then continues to be driven by the drive unit 200 to switch to flow axially into the blood flow channel 103; another portion of the blood F1 can be guided by the distal end of the catheter 12 to flow axially into the inlet groove 106, and is axially introduced into the inner side of the liquid inlet 101 through the inlet groove 106, thereby pushing the portion of blood F2 entering from the liquid inlet 101 to flow axially, thereby pushing the blood F2 to flow into the blood flow channel 103 at an accelerated speed, thereby effectively increasing the blood flow entering from the liquid inlet 101 and improving the blood pumping efficiency of the blood pump 10.

[0075] 3 and 4 , the pump casing 100 optionally includes a casing tube 110, with the motor 210 and impeller 220 both located within the casing tube 110. The casing tube 110 includes an inlet pipe 111, a fixed pipe 112, and a connecting pipe 113. The inlet pipe 111 and the connecting pipe 113 are respectively connected to the ends of the fixed pipe 112. The inlet pipe 111 is provided with a liquid inlet 101, and the end of the inlet pipe 111 away from the fixed pipe 112 is fixedly connected to the proximal end of the motor 210. The inner wall of the fixed pipe 112 is fixedly connected to the outer circumference of the motor 210 via a support member.

[0076] Specifically, the fixed tube 112 is looped around the outer periphery of the motor 210, and the inner wall surface of the fixed tube 112 is spaced apart from the outer periphery of the motor 210; the inner wall surface of the fixed tube 112 is provided with a plurality of support members, and the plurality of support members are fixedly connected to the outer periphery of the motor 210 to support and fix the fixed tube 112. The fixed tube 112 forms the side wall of the middle portion of the shell tube 110. Therefore, the fixed tube 112 is stably supported by the support members, so that the fixed tube 112 plays a central supporting role on the shell tube 110, so that the inlet tube 111 and the connecting tube 113 can both have a stable relative position relative to the outer surface of the motor 210, thereby improving the structural stability of the blood flow channel 103 constructed between the shell tube 110 and the drive unit 200.

[0077] It is worth mentioning that there is no specific limitation on the shape and structure of the above-mentioned support member. The support member 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 111 of the shell tube 110 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 fixed tube 112; and the connecting tube 113 of the shell tube 110 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 fixed tube 112. In this way, the shell tube 110 and the motor 210 are connected and fixed, which improves the convenience of assembly.

[0078] 3 and 4 , the motor 210 optionally includes a motor body 211 and a shaft support 212 connected to the distal end of the motor body 211. The outer diameter of the shaft support 212 is gradually reduced in the direction from the motor 210 to the impeller 220, so that the outer peripheral surface of the shaft support 212 forms a tapered guide surface 213. The tapered guide surface 213 can guide blood passing through the periphery of the motor 210 to gradually deflect toward the central axis of the impeller 220, and then flow toward the central area of ​​the impeller 220. In other words, the blood can be gradually guided to the central area of ​​the impeller 220 by the shaft support 212 to adapt to the radial dimension difference between the motor 210 and the hub 221 of the impeller 220.

[0079] Furthermore, a rectifier plate 230 is provided on the conical guide surface 213, and a plurality of rectifier plates 230 are arranged at intervals along the circumference of the conical guide surface 213, and the plurality of rectifier plates 230 all extend along the axial direction of the motor 210. The rectifier plates 230 can be integrally formed with the shaft support seat 212. Specifically, the plurality of rectifier plates 230 are fixed on the conical guide surface 213 at intervals along the circumference of the shaft support seat 212 to form a linearly extending rectifier channel between two adjacent rectifier plates 230. In other words, the rectifier channel extends linearly along the axial direction of the motor 210 so as to be able to guide the blood in the blood flow channel 103 to flow axially into the impeller 220.

[0080] In this way, the plurality of rectifying plates 230 can define a rectifying channel in pairs, so that the rectifying device 400 has a plurality of linearly extending rectifying channels, and the plurality of rectifying channels are spaced apart along the circumference of the shaft support seat 212. When blood flows to the periphery of the shaft support seat 212, the plurality of rectifying plates 230 divide the blood into a plurality of orderly blood flows that flow stably along the axial direction. These orderly blood flows will flow into the impeller 220 along the axial direction.

[0081] In addition, the side of the rectifying plate 230 away from the conical guide surface 213 can be fixedly connected to the inner wall surface of the fixed pipe 112, so that the rectifying plate 230 serves as the supporting member to support the fixed pipe 112.

[0082] 3 and 4 , based on any of the above-mentioned embodiments, the impeller 220 of the drive unit 200 includes a hub 221 and blades 222 provided on the hub 221; the diameter of the hub 221 is gradually increased in 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 pump housing 100 gradually decreases in the direction of the diameter expansion of the hub 221. The diameter expansion direction is the direction from the motor 210 to the impeller 220. This arrangement can make the distal end diameter of the hub 221 larger, so that the distance K2 between the distal end outer circumference of the hub 221 and the inner circumference of the pump housing 100 is smaller than the distance K1 between the proximal end outer circumference of the hub 221 and the inner circumference of the pump housing 100, that is, K2 < K1.

[0083] Blood 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 is gradually compressed by the spiral in this process, so that part of the radial potential energy of the blood obtained by being driven spirally by the impeller 220 is converted into axial potential energy, which increases the axial potential energy of the blood, thereby increasing the component velocity of the blood flowing along the axial direction, so that the blood is discharged quickly along the axial outlet 102.

[0084] Because the diameter of hub 221 gradually increases from motor 210 to impeller 220, hub 221 has a fourth outer diameter D1 at its distal end, which represents its maximum diameter. Impeller 220 has a fifth outer diameter D2, which represents its maximum diameter when the impeller 220 rotates as a whole. Insensitive ring 300 has a second inner diameter B1, which represents its minimum inner diameter. Optionally, second inner diameter B1 is greater than fourth outer diameter D1 and smaller than fifth outer diameter D2, i.e., D1 < B1 < D2.

[0085] Specifically, the second inner diameter B1 corresponds to the diameter of the liquid outlet 102. This second inner diameter B1 is smaller than the fifth outer diameter D2, meaning that the diameter of the liquid outlet 102 is smaller than the maximum diameter of the impeller 220, thereby forming a constricted opening relative to the blood flow channel 103. When blood is discharged from the liquid outlet 102, it is compressed, raising blood pressure. This allows the blood to acquire greater kinetic potential energy upon discharge into the pulmonary artery 26, thereby increasing the blood flow rate within the pulmonary artery 26. Furthermore, the second inner diameter B1 is larger than the fourth outer diameter D1, meaning that the diameter of the liquid outlet 102 is larger than the maximum diameter of the distal end of the hub 221. As a result, blood discharged axially from the distal end of the hub 221 does not directly impact the peripheral edge of the liquid outlet 102, thereby reducing kinetic energy loss, increasing the blood discharge velocity, and improving pumping efficiency.

[0086] Figures 13 to 23 illustrate another embodiment of a blood pump 10 provided by the present application. Referring to Figures 13 to 15 , in this embodiment, the blood pump 10 includes a pump body 11 and a catheter 12, with the catheter 12 connected to the proximal end of the pump body 11. The pump body 11 includes a pump housing 100 and a drive unit 200. The pump housing 100 is provided with a liquid inlet 101, and the distal end of the pump housing 100 is open, so that the distal end of the pump housing 100 serves as a liquid outlet 102. The drive unit 200 includes an impeller 220 disposed within the pump housing 100, with the impeller 220 pointing toward the liquid outlet 102.

[0087] 24 , when the blood pump 10 is implanted in a patient, the pump body 11 of the blood pump 10 can be passed from the inferior vena cava 20 or the superior vena cava 21, sequentially through the right atrium 22, the tricuspid valve 23, the right ventricle 24, and the pulmonary valve 25, to the pulmonary artery 26, with at least the liquid outlet 102 of the pump body 11 extending into the pulmonary artery 26. When the blood pump 10 is in operation, the drive unit 200 drives the impeller 220 to rotate, causing blood to enter the pump housing 100 from the liquid inlet 101. The blood is then accelerated by the impeller 220 within the pump housing 100 and finally discharged from the liquid outlet 102 to the pulmonary artery 26, thereby assisting the right ventricle 24 in pumping blood to the pulmonary artery 26. Obviously, blood flows in the pump housing 100 along the axial direction of the impeller 220.

[0088] Since the impeller 220 in the present application points to the liquid outlet 102, that is, the liquid outlet 102 and the impeller 220 are opposite to each other along their axial direction, when the blood flows along the axial direction of the impeller 220 to the liquid outlet 102, it will continue to flow and be discharged from the liquid outlet 102 along the axial direction of the impeller 220, so that the blood is basically not blocked by other components, and the flow direction of most of the blood does not change significantly, so that the kinetic energy loss of the discharged blood is small, and the blood can be discharged from the liquid outlet 102 more quickly, which is conducive to increasing the amount of blood discharged from the liquid outlet 102. Furthermore, since the liquid outlet 102 is opposite to the impeller 220, the liquid outlet 102 is not located on the side wall of the pump housing 100. Therefore, when the side wall of the pump body 11 accidentally abuts against the inner wall of the tissue, the liquid outlet 102 is not easily blocked by the inner wall of the tissue, and the liquid outlet 102 can normally supply blood for discharge.

[0089] 15 and 16 , the present application also considers that, because the wall thickness H2 of the pump housing 100 itself is typically small, the width of the distal end surface of the pump housing 100 (i.e., the periphery of the liquid outlet 102) extending radially along the pump housing 100 is substantially equal to H2, resulting in a relatively sharp periphery of the liquid outlet 102. During implantation of the blood pump 10 into a patient, the blood pump 10 is pushed into the patient along the direction from the catheter 12 to the pump body 11. The periphery of the liquid outlet 102 of the pump body 11 may contact and scratch the inner wall of the tissue. In view of this, in order to reduce the occurrence of the periphery of the liquid outlet 102 scratching the inner wall of the tissue, in the present application, the pump body 11 is also provided with a desensitizing ring 300, which is arranged on the periphery of the distal end of the pump casing 100. At least the distal end of the desensitizing ring 300 is provided with a desensitizing wall 310, which extends along the circumferential direction of the desensitizing ring 300. The desensitizing wall 310 has a radial width H1 along the radial direction of the pump casing 100, and the radial width H1 is greater than the tube wall thickness H2 of the pump casing 100, that is, H1>H2.

[0090] Specifically, the insensitive wall 310 extends along the circumferential direction of the insensitive ring 300, wherein the circumferential direction of the insensitive ring 300 refers to the direction surrounding the central axis M1M2 of the impeller 220. By setting the radial width H1 of the insensitive wall 310 to be greater than the wall thickness H2 of the pump housing 100, the radial width H1 of the insensitive wall 310 can be ensured to be large, thereby increasing the surface area of ​​the insensitive wall 310, improving the insensitivity of the insensitive ring 300, and making the insensitive ring 300 less sharp. In this way, during the implantation of the blood pump 10 into the patient's body, the periphery of the liquid outlet 102 of the pump body 11 contacts the inner wall of the tissue through the insensitive wall 310 of the insensitive ring 300. Due to the strong insensitivity of the insensitive wall 310, it is not easy to scratch the inner wall of the tissue, thereby reducing the possibility of the periphery of the liquid outlet 102 damaging the inner wall of the tissue.

[0091] The pump housing 100 includes a main section 110 and a reducing section 120 connected to the main section 110; the main section 110 is provided with a liquid inlet 101; a desensitizing ring 300 is provided on the periphery of the distal end of the reducing section 120, such that the inner periphery of the desensitizing ring 300 and the inner periphery of the reducing section 120 jointly define a liquid outlet 102. The direction in which the impeller 220 points toward the liquid outlet 102 is referred to as a first direction; the diameter of the liquid outlet 102 is configured to gradually increase along the first direction, so that the liquid outlet 102 has a flared shape. This configuration ensures that the desensitizing ring 300 does not block the flow surface of the liquid outlet 102, and the flow surface area of ​​the liquid outlet 102 gradually increases from its proximal end to its distal end, thereby reducing the resistance of the liquid outlet 102 to blood flow, allowing blood to be quickly discharged from the liquid outlet 102, and effectively increasing the amount of blood discharged from the liquid outlet 102.

[0092] Specifically, the pump housing 100 is coaxial with the impeller 220, and both have a central axis M1M2. The central axis M1M2 is a virtual line that passes through the center of the cross section of the pump housing 100 and extends along the length direction of the pump housing 100, and M1 and M2 are two points on the virtual line respectively. The direction from M1 to M2 represents the direction from the proximal end to the distal end of the blood pump 10. The first direction is the direction along the central axis M1M2 and from M1 to M2. It can be understood that since the inner circumference of the insensitive ring 300 and the inner circumference of the reducing section 120 jointly define the liquid outlet 102, the diameter of the liquid outlet 102 is set to gradually increase along the first direction, that is, the inner diameter of the insensitive ring 300 and the inner diameter of the reducing section 120 are gradually increased along the first direction.

[0093] The technical solution of the present application is to provide a reducing section 120 on the pump housing 100 and a desensitizing ring 300 on the periphery of the distal end of the reducing section 120, so that the inner periphery of the desensitizing ring 300 and the inner periphery of the reducing section 120 jointly define a liquid outlet 102; the diameter of the liquid outlet 102 gradually increases in the direction from the impeller 220 to the liquid outlet 102, so that the liquid outlet 102 has a flared shape. This arrangement can ensure that the desensitizing ring 300 does not block the flow surface of the liquid outlet 102, so that the flow surface area of ​​the liquid outlet 102 will gradually increase from its proximal end to its distal end, thereby reducing the resistance of the liquid outlet 102 to the blood flow, allowing blood to be quickly discharged from the liquid outlet 102, and effectively increasing the amount of blood discharged from the liquid outlet 102. Furthermore, a desensitizing wall 310 is provided on the desensitizing ring 300. The desensitizing wall 310 extends circumferentially around the desensitizing ring 300, and the radial width H1 of the desensitizing wall 310 along the radial direction of the pump housing 100 is greater than the wall thickness H2 of the pump housing 100. This ensures that the radial width H1 of the desensitizing wall 310 is large, thereby increasing the surface area of ​​the desensitizing wall 310, improving the sensitivity of the desensitizing ring 300, and making the desensitizing ring 300 less sharp. Thus, during implantation of the blood pump 10 into a patient, the periphery of the liquid outlet 102 can contact the inner wall of the tissue through the desensitizing wall 310 of the desensitizing ring 300. Due to the strong sensitivity of the desensitizing wall 310, the inner wall of the tissue is less likely to be scratched. This reduces the risk of the periphery of the liquid outlet 102 damaging the inner wall of the tissue during implantation, thereby improving the safety of the blood pump 10 during implantation.

[0094] Referring to Figures 15 to 17 , for the pump housing 100 of the pump body 11, the main section 110 of the pump housing 100 can be configured as a straight tube shape or other non-straight tube shape. In this embodiment, the main section 110 of the pump housing 100 is configured as a straight tube shape. The inner circumferential surface of the main section 110 is designated as a first inner circumferential surface 111, and the outer circumferential surface of the main section 110 is designated as a first outer circumferential surface 112; both the first inner circumferential surface 111 and the first outer circumferential surface 112 are cylindrical surfaces. Regarding the reducing section 120 of the pump housing 100, the reducing section 120 can be integrally formed with the insensitive ring 300. The inner circumferential surface of the variable diameter section 120 is recorded as the second inner circumferential surface 121, and the outer circumferential surface of the variable diameter section 120 is recorded as the second outer circumferential surface 122; wherein, the second inner circumferential surface 121 is connected between the first inner circumferential surface 111 of the main body section 110 and the insensitive wall 310, and the second inner circumferential surface 121 constitutes the proximal part of the inner surface of the liquid outlet 102; the second outer circumferential surface 122 is connected between the first outer circumferential surface 112 of the main body section 110 and the insensitive wall 310.

[0095] Optionally, the inner circumference of the reducing section 120 (i.e., the second inner circumference 121) has a first diameter C1, which constitutes the inner diameter of the reducing section 120. The first diameter C1 gradually increases along the first direction, so that the liquid outlet 102 gradually increases along the first direction. The outer circumference of the reducing section 120 (i.e., the second outer circumference 122) has a second diameter, and the second diameter C2 can remain unchanged along the first direction, so that the second outer circumference 122 is cylindrical. The wall thickness of the pump housing 100 at the reducing section 120 is recorded as the first wall thickness H. 2a , then the first tube wall thickness H 2a It is 1 / 2 times the difference between the second diameter C2 and the first diameter C1, that is, H 2a =(C2-C1) / 2, and H 2a

[0096] If the radial width H1 of the insensitive wall 310 is equal to the first tube wall thickness H 2a The difference is recorded as the transition step difference △H, then △H=H1-H 2a =H1-(C2-C1) / 2. It can be understood that the larger the transition step ΔH is, the easier it is to form an abrupt and sharp transition step at the connection between the reducing section 120 and the insensitive wall 310. Therefore, on the basis that the first diameter C1 of the reducing section 120 gradually increases along the first direction, if the second diameter C2 of the reducing section 120 remains unchanged along the first direction, then the first tube wall thickness H 2a It will gradually become smaller along the first direction, and the transition step difference △H will gradually increase along the first direction. The transition step difference △H reaches the maximum at the connection between the adjacent variable diameter section 120 and the insensitive wall 310, so that a sharp transition step is easily formed at the connection between the variable diameter section 120 and the insensitive wall 310.

[0097] In view of the above situation, in this embodiment, the second diameter C2 of the reducing section 120 is set to gradually increase along the first direction, so that the reducing section 120 can be outward-turned relative to the main section 110, and the wall thickness H of the reducing section 120 is 2a Gradually increasing or remaining unchanged, or decreasing to a lesser extent, along the first direction can make the transition step difference △H at the connection between the adjacent variable diameter section 120 and the insensitive wall 310 reach a minimum, so that the distal end of the second outer peripheral surface 122 and the outer peripheral edge of the insensitive wall 310 can be connected together more smoothly, thus avoiding the formation of a sharp transition step at the connection between the two.

[0098] Furthermore, the first wall thickness H of the diameter-reducing section 120 is 2a ​It gradually increases along the first direction, that is, the difference between the second diameter C2 and the first diameter C1 gradually increases along the first direction. Obviously, as the diameter of the liquid outlet 102 gradually increases along the first direction, the first tube wall thickness H of the variable diameter section 120 2a Also gradually increases along the first direction, rather than becoming smaller, which can make the first tube wall thickness H at the distal end of the diameter-reducing section 120 2a The diameter-changing section 120 and the insensitive wall 310 are connected together more smoothly, and it is not easy to form a sharp transition step at the connection between the diameter-changing section 120 and the insensitive wall 310.

[0099] Referring to Figures 20 to 22 , specifically, the second inner circumferential surface 121 is curved in an arc shape, so that the second inner circumferential surface 121 is smoothly connected to the inner circumference of the insensitive wall 310. The smooth connection means that there are no sharp edges or corners at the connection. For example, the smooth connection can be achieved by setting the connection to be rounded or arc-shaped. This allows the second inner circumferential surface 121 to smoothly transition to the insensitive wall 310, making the inner surface of the liquid outlet 102 smoother, reducing the resistance to blood flow, facilitating the rapid discharge of blood from the liquid outlet 102, and increasing the amount of blood discharged. Of course, the second outer circumferential surface 122 can also be curved in an arc shape, so that the second outer circumferential surface 122 is smoothly connected to the outer circumferential edge of the insensitive wall 310. This can make the distal outer surface of the pump housing 100 smoother. During the implantation of the blood pump 10 in the patient, when the distal end of the pump housing 100 contacts the inner wall of the tissue, it is less likely to scratch the inner wall of the tissue, thereby improving the safety of the blood pump 10 implanted in the patient. Optionally, the second inner circumferential surface 121 and the second outer circumferential surface 122 are both curved in an arc shape.

[0100] Referring to Figures 21 and 22, further, the curvature of the second outer peripheral surface 122 is greater than the curvature of the second inner peripheral surface 121. Assuming that the radius of the arc where the second inner peripheral surface 121 is located is R1, and the radius of the arc where the second outer peripheral surface 122 is located is R2, then 1 / R2>1 / R1, that is, R1>R2. This arrangement can make the curvature of the second outer peripheral surface 122 greater than the curvature of the second inner peripheral surface 121, thereby making the first tube wall thickness H of the variable diameter section 120 2a It gradually increases along the first direction, effectively reducing the transition step difference ΔH, thereby ensuring that the diameter-reducing section 104 can be better connected with the insensitive ring 300 to form an integral whole.

[0101] 21 and 22 , the inner periphery of the insensitive wall 310 is smoothly connected to the inner periphery of the reducing section 120, and the outer periphery of the insensitive wall 310 is smoothly connected to the outer periphery of the reducing section 120. This smooth connection also means that there are no sharp edges or corners at the connection, and this can be achieved, for example, by rounding or arcing the connection. Specifically, the inner periphery of the insensitive wall 310 is connected to the inner periphery of the variable diameter section 120 (i.e., the second inner periphery 121) to form a first connection 301; the outer periphery of the insensitive wall 310 is connected to the outer periphery of the variable diameter section 120 (i.e., the second outer periphery 122) to form a second connection 302; wherein, the inner periphery of the insensitive wall 310 is smoothly connected to the inner periphery of the variable diameter section 120, that is, the first connection 301 does not form sharp edges and corners, making the inner surface of the liquid outlet 102 relatively smooth, thereby reducing blood flow resistance. Similarly, the outer periphery of the insensitive wall 310 is smoothly connected to the outer periphery of the variable diameter section 120, that is, the second connection 302 does not form sharp edges and corners, thereby preventing the second connection 302 from scratching the inner wall of the tissue.

[0102] The insensitive wall 310 curves in a convex arc from the first connection 301 to the second connection 302. This arrangement makes the insensitive wall 310 relatively rounded and smooth. Furthermore, the inner periphery of the insensitive wall 310 smoothly transitions to the inner circumference of the reducing section 120 through its own arc, thereby achieving a smooth connection with the inner circumference of the reducing section 120. Similarly, the outer periphery of the insensitive wall 310 also smoothly transitions to the outer circumference of the reducing section 120 through its own arc, thereby achieving a smooth connection with the outer circumference of the reducing section 120. This prevents the edge of the liquid outlet 102 from being too sharp and scratching the inner tissue wall. Furthermore, during implantation of the blood pump 10 in a patient, the distal end of the pump body 11 is prevented from scratching the patient's internal tissue. Specifically, the insensitive wall 310 is convexly curved, extending away from the main section 110. The convex arc of the insensitive wall 310 can be a circular arc or an elliptical arc. Of course, the shape of the insensitive wall 310 is not limited to this. In other embodiments, the insensitive wall 310 can be configured as a flat wall extending radially along the pump housing 100, and the inner edge of the insensitive wall 310 is provided with a first chamfer, which is smoothly connected to the inner circumference of the reducing section 120 (i.e., the second inner circumference 121) through the first chamfer; the outer periphery of the insensitive wall 310 is provided with a second chamfer, which is smoothly connected to the outer circumference of the reducing section 120 (i.e., the second outer circumference 122) through the second chamfer. Such an insensitive wall 310 can also have a strong insensitivity.

[0103] Referring to Figures 16 to 18 , the first outer circumferential surface 112 of the main body segment 110 has a third diameter C3. The insensitive wall 310 has a radial section S1 perpendicular to the central axis M1M2 of the impeller 220. The circular tangent formed by the insensitive wall 310 and the radial section S1 is designated as the distal circumferential line 303. Distal circumferential line 303 is located between the first connection 301 and the second connection 302. Distal circumferential line 303 has an inner diameter E that is greater than the third diameter C3 of the main body segment 110, i.e., E>C3. It will be appreciated that because distal circumferential line 303 is a circular tangent formed by the insensitive wall 310 and the radial section S1, the axial distance between distal circumferential line 303 and the main body segment 110 is greater than the axial distance between any other circumferential lines of the insensitive wall 310 and the main body segment 110.

[0104] Specifically, because the insensitive ring 300 is disposed at the distal end of the reducing section 120, and the inner circumferential space of the insensitive ring 300 constitutes a portion of the liquid outlet 102, the circular inner diameter E of the insensitive wall 310 corresponds to the maximum diameter of the liquid outlet 102. By setting the circular inner diameter E to be greater than the third diameter C3, the maximum diameter of the liquid outlet 102 can be made greater than the third diameter C3 of the main section 110. As a result, the flow surface area of ​​the liquid outlet 102 is greater than the cross-sectional area of ​​the main section 110. This significantly increases the flow surface area of ​​the liquid outlet 102, thereby increasing the blood discharge volume of the liquid outlet 102.

[0105] Referring to Figures 15 to 17 , it can be understood that the reducing section 120 extends a distance from the distal end of the main section 110 toward the direction away from the main section 110, such that the inner diameter of the reducing section 120 gradually increases along the direction from the impeller 220 to the liquid outlet 102, thereby giving the liquid outlet 102 a flared shape. Therefore, the reducing section 120 has a starting end 123 connected to the main section 110 and a distal end remote from the main section 110. The starting end 123 corresponds to the minimum inner diameter of the liquid outlet 102, while the distal end is connected to the insensitive ring 300.

[0106] Referring to Figures 16 to 18 , the radial spacing between the distal circumference 303 of the insensitive wall 310 and the first inner circumferential surface 111 of the main body section 110 is recorded as the diameter expansion deviation D1; the axial spacing between the starting end 123 of the variable diameter section 120 and the radial section S1 is recorded as the total outlet length D2, and the total outlet length D2 is greater than the diameter expansion deviation D1. It can be understood that the diameter expansion deviation D1 is equivalent to 1 / 2 times the difference between the minimum diameter and the maximum diameter of the liquid outlet 102; the total outlet length D2 is equivalent to the total axial length of the liquid outlet 102. By setting the total outlet length D2 to be greater than the diameter expansion deviation D1, the total axial length of the liquid outlet 102 can be ensured to be longer. When blood is discharged from the liquid outlet 102, it can be guided by the inner surface of the liquid outlet 102 to flow for a distance, thereby enhancing the diversion effect of the liquid outlet 102 in guiding the discharge of blood.

[0107] Optionally, the ratio of the total outlet length D2 to the diameter expansion deviation D1 is 2.5 to 4.5, i.e., 2.5 ≤ D2 / D1 ≤ 4.5. By limiting the range to 2.5 ≤ D2 / D1 ≤ 4.5, the total outlet length D2 can be 2.5 to 4.5 times the diameter expansion deviation D1, thereby increasing the total outlet length of the liquid outlet 102 and facilitating the liquid outlet 102 to guide the blood to diffuse outward. On the other hand, assuming that the outward inclination angle of the second inner circumferential surface 121 of the reducing section 120 relative to the first inner circumferential surface 111 of the main section 110 is θ, then θ ≤ arctan(D1 / D2). Since 2.5≤D2 / D1≤4.5 in this embodiment, a larger value of D1 / D2 can be defined accordingly, and thus a larger value of the inclination angle θ that is suitable for setting can be roughly obtained, thereby preventing the inclination angle θ from being too large and preventing the reducing section 120 from protruding radially outward too much relative to the first outer peripheral surface 112 of the main section 110, thereby reducing the difficulty of the reducing section 120 passing through the blood vessels in the patient's body.

[0108] Referring to Figures 15 to 17 , a plane perpendicular to the central axes M1M2 of the impeller 220 and passing through the starting end 123 is designated as the radial marking plane S2. The impeller 220 is disposed within the main body section 110, and the distal end of the impeller 220 extends to the radial marking plane S2, or alternatively, the distal end of the impeller 220 passes through the radial marking plane S2 to extend into the reducing section 120. Specifically, the impeller 220 includes a hub 221 and blades 222 disposed on the hub 221. The distal end of the hub 221 extends to the radial marking plane S2 or passes through the radial marking plane S2. The radial marking plane S2 is parallel to and spaced from the radial tangential plane S1. If the distal end of the hub 221 extends to the radial marking plane S2, the distal end of the impeller 220 can be aligned with the starting end 123 of the reducing section 120 and both are located on the radial marking plane S2. In particular, if the distal end of the hub 221 passes through the radial marking surface S2 , the distal end of the impeller 220 can extend into the interior of the reducing section 120 , that is, into the liquid outlet 102 .

[0109] When the blood pump 10 is running, the impeller 220 rotates and drives the blood in the main section 110 to spirally propel toward the reducing section 120; when the blood separates from the impeller 220, a portion of the blood F1 has axial potential energy to flow along the axial direction of the impeller 220, and this portion of blood is directly discharged axially from the central area of ​​the liquid outlet 102; the other portions of blood F2 and F3 have radial potential energy to deflect radially along the impeller 220, and this portion of blood can just be radially deflected at the starting end of the reducing section 120 and contact the second inner circumferential surface 121 of the reducing section 120, and then will be guided and discharged along the circumference of the reducing section 120 by the second inner circumferential surface 121, so that this portion of blood can be quickly diffused and discharged circumferentially from the liquid outlet 102, effectively increasing the blood discharge volume of the liquid outlet 102.

[0110] Referring to Figures 18 and 20 to 22, for the insensitive ring 300, the insensitive wall 310 can make the surface of the insensitive ring 300 more rounded and smooth, and less likely to cut the inner wall of the tissue. Optionally, the insensitive wall 310 is located on a torus, so that the insensitive wall 310 is curved in an arc shape from the first connection 301 to the second connection 302. The center O1 of the mother circle 305 of the torus is located inside the insensitive ring 300, and the mother circle 305 has the radial width H1 of the insensitive ring 300 as its diameter. The torus refers to a circular ring structure formed by rotating a circle around an axis that does not intersect the circle; the circle is referred to as the mother circle 305 of the torus. For example, structures such as swimming rings, donuts, and hula hoops are all in the shape of torus.

[0111] Specifically, the insensitive ring 300 can be configured as a torus as a whole, so that the entire surface of the insensitive ring 300 forms the insensitive wall 310. In this case, the radial width H1 of the insensitive wall 310 is the diameter of the parent circle 305 of the torus. Of course, the insensitive ring 300 itself may not be a torus, but only a portion of its surface may be configured as the insensitive wall 310. The torus containing the insensitive wall 310 is a virtual torus designed to create the shape of the insensitive wall 310. Regardless of whether the torus containing the insensitive wall 310 is the insensitive ring 300 itself or a virtual torus, the center O1 of the parent circle 305 of the torus should be located within the interior of the insensitive ring 300, so that the insensitive wall 310 is convex outward relative to the interior of the torus 300, thereby making the circumference of the insensitive ring 300 relatively round and smooth. When the blood pump 10 is implanted in a patient's body, the distal end of the pump body 11 can contact the inner wall of the tissue through the insensitive ring 300. Since the insensitive wall 310 of the insensitive ring 300 is relatively round and smooth, it is not easy to scratch the inner wall of the tissue, thereby avoiding causing damage to the patient's internal tissue.

[0112] Referring to Figures 21 to 23 , in one embodiment, the circular tangent formed by the insensitive wall 310 and the radial section S1 is denoted as the distal circumferential line 303. The distal circumferential line 303 divides the insensitive wall 310 into an inner arc wall 311 and an outer arc wall 312. The inner arc wall 31 is located between the first connection 301 and the distal circumferential line 303, and constitutes the distal portion of the inner surface of the liquid outlet 102. The outer arc wall 312 is located between the distal circumferential line 303 and the second connection 302. The outer arc wall 312 connects to the second outer peripheral surface 122 to form the second connection 302. Optionally, the inner arc wall 311 has a first central angle α1, which is less than or equal to 90°, that is, α1≤90°; the outer arc wall 312 has a second central angle α2, which is greater than 90°, that is, α2>90°.

[0113] For the first central angle α1, it is obvious that α1>0°. If α1>90°, the first connection 301 between the inner arc wall 311 and the second inner circumferential surface 121 will be recessed toward the outer arc wall 312. This recessed area can easily block blood flow and increase the resistance to blood discharge. Therefore, by setting α1≤90° in this embodiment, the first connection 301 can be made smoother, so that the inner arc wall 311 and the second inner circumferential surface 121 are smoothly connected to form a complete smooth inner surface, and this smooth inner surface is in an inward convex arc shape. This can help reduce the resistance to blood discharge and make blood discharge from the liquid outlet 102 smoother.

[0114] For the second central angle α2, theoretically the second central angle α2 can be 0°<α2≤180°. However, considering that the radial width H1 of the insensitive wall 310 is greater than the wall thickness H2 of the pump casing 100, the insensitive wall 310 has a highest point 304 that protrudes radially relative to the first outer peripheral surface 112 of the main body section 110. When α2≤90°, the entire outer arc wall 312 is located between the distal circumferential line 303 and the highest point 304, and the second connection 302 will be at the highest point 304, that is, the second connection 302 and the highest point 304 coincide. In this case, it is difficult for the outer arc wall 312 to be smoothly connected to the second outer peripheral surface 122, making it easy for the second connection 302 to have ridges or sharp edges. For ease of understanding, the tangent of the outer arc wall 312 at the highest point 304 is recorded as the original tangent T0, and the tangent at the distal end of the second outer peripheral surface 122 is recorded as the first tangent T1; at this time, the original tangent T0 and the first tangent T1 intersect to form a first angle β1. The first angle β1 is large, so that the outer arc wall 312 and the second outer peripheral surface 122 are difficult to connect smoothly, and it is very easy for a ridge or sharp edge to appear at the second connection 302, which will increase the difficulty of implanting the blood pump 10 into the patient's body.

[0115] In view of the above, this embodiment sets α2>90°, so that the highest point 304 of the insensitive ring 300 divides the outer arc wall 312 into a first arc wall 312a and a second arc wall 312b. The first arc wall 312a is located between the distal circumferential line 303 and the highest point 304, and the second arc wall 312b is located between the highest point 304 and the second outer peripheral surface 122. The tangent of the second arc wall 312b at the second connection 302 is denoted as the second tangent T2. The second tangent T2 and the first tangent T1 intersect to form a second angle β2, which is less than the first angle β1, i.e., β2<β1. In this way, the second arc wall 312b can be smoothly connected to the second outer peripheral surface 122 at the second connection 302, so that the outer arc wall 312 and the second outer peripheral surface 122 are smoothly connected to form a relatively smooth outer surface. Furthermore, as α2 increases, the second angle β2 between the second tangent line T2 and the first tangent line T1 gradually decreases until the second angle β2 decreases to 0, at which point the second tangent line T2 and the first tangent line T1 coincide with each other. At this point, the outer arc wall 312 is most smoothly connected to the second outer peripheral surface 122. This prevents ridges or sharp edges from forming at the second connection 302, thereby preventing the second connection 302 from scratching the inner wall of tissue, and facilitating easier implantation of the blood pump 10 in a patient.

[0116] Referring to Figures 15, 21, and 22, in one embodiment, the radial height of the desensitizing ring 300 relative to the outer circumferential surface (first outer circumferential surface 112) of the main body section 110 is designated as radial projection D3. This radial projection D3 corresponds to the radial distance from the highest point 304 to the first outer circumferential surface 112 of the main body section 110. It will be appreciated that the greater the radial projection D3, the more insensitive the desensitizing ring 300 is, and the less likely it is to scratch the inner tissue wall. However, a greater radial projection D3 also increases the radial dimension of the desensitizing ring 300, which in turn increases the radial dimension of the distal end of the pump body 11, making implantation of the pump body 11 more difficult.

[0117] Based on this, the radial convex height D3 should be kept within a certain range. Optionally, the wall thickness of the pump casing 100 at the main section 110 is recorded as the second wall thickness H2b, H 2b 2b The ratio is 1.3 to 1.8, that is, 1.3≤D3 / H 2b ≤1.8. This is equivalent to 1.3H 2b ≤D3≤1.8H 2b ​With this arrangement, the radial convex height D3 of the insensitive ring 300 is maintained within a preferred range, thereby ensuring that the radial convex height D3 of the insensitive ring 300 is not too small, making the insensitive ring 300 more sensitive and less likely to scratch the inner wall of the tissue; furthermore, the radial convex height D3 is not too large, making the radial dimension of the distal end of the pump body 11 smaller, and making it less difficult to implant the pump body 11 into the patient's body.

[0118] Referring to Figure 19, in one embodiment, the pump housing 100 includes a shell tube 103 fixedly connected to the drive unit 200, and an extension tube 104 connected to the distal end of the shell tube 103. The reducing section 120 and the insensitive ring 300 are both arranged on the extension tube 104, and the insensitive ring 300 constitutes the farthest end of the blood pump 10. The shell tube 103 and the extension tube 104 are two separately molded components. The insensitive ring 300 can be integrally molded with the reducing section 120 on the extension tube 104 to reduce the number of parts and reduce the processing and assembly steps. Of course, in other embodiments, the insensitive ring 300 can also be manufactured and molded separately, and then fixed to the extension tube 104. Specifically in this embodiment, the insensitive ring 300 and the reducing section 120 are integrally molded on the extension tube 104

[0119] It is understood that only the distal end of the extension tube 104 can be configured as the reducing section 120 of the pump housing 100. Alternatively, the entire extension tube 104 can be configured as the reducing section 120 of the pump housing 100, i.e., the extension tube 104 gradually reduces in diameter from its proximal end to its distal end to form the reducing section 120, and the insensitive ring 300 is connected to the distal end of the reducing section 120. If only the distal end of the extension tube 104 is configured as the reducing section 120 of the pump housing 100, the proximal end of the extension tube 104 is configured as the main body 120 of the pump housing 100. Alternatively, the proximal end of the extension tube 104 and the housing tube 103 can both be straight tubes, and after the proximal end of the extension tube 104 and the housing tube 103 are connected, the proximal end of the extension tube 104 and the housing tube 103 together constitute the main body 120 of the pump housing 100. If the entire extension tube 104 is configured as the diameter-reducing section 120 of the pump housing 100 , the housing tube 103 is configured as the main body section 110 of the pump housing 100 .

[0120] Optionally, the shell tube 103 is also configured as a straight tube; the shell tube 103 and the proximal end portion of the extension tube 104 are coaxial and of equal diameter. Specifically, the shell tube 103, the extension tube 104, and the impeller 220 are all coaxial, and the impeller 220 is primarily located within the shell tube 103 and extends from the shell tube 103 into the extension tube 104.

[0121] Optionally, the extension tube 104 is configured as an elastic structure. This allows the extension tube 104 to be elastic, so that when the insensitive ring 300 abuts the inner wall of the tissue during implantation of the blood pump 10, the extension tube 104 can undergo elastic deformation to buffer the force exerted by the insensitive ring 300 on the inner wall of the tissue. It is understandable that since the insensitive ring 300 and the reducing section 120 are both provided on the extension tube 104, the insensitive ring 300 and the reducing section 120 are both elastic. The elastic structure refers to a structure made of an elastic material, which may be a TPU material. Of course, in other embodiments, the extension tube 104 may also be configured as a rigid structure, so that the extension tube 104 is rigid. For example, the rigid structure may be made of a metal material.

[0122] Because the curvature of the second outer circumferential surface 122 is greater than that of the second inner circumferential surface 121, an annular recess 105 is formed on the outer side of the second outer circumferential surface 122. When the extension tube 104 is configured as an elastic structure, the presence of the annular recess 105 can enhance the amplitude of elastic deformation of the extension tube 104 along the axial direction of the impeller 220, further buffering the reaction force of the insensitive ring 300 on the inner tissue wall. After the blood pump 10 penetrates the pulmonary artery 26, when the distal end of the pump body 11 is subjected to a force along the axial direction of the impeller 220, the extension tube 104 is more likely to bend outward from the annular recess 105 rather than inward from the liquid outlet 102, making it less likely that the bent portion will block the liquid outlet 102.

[0123] Referring to Figures 15 and 16 , in one embodiment, the impeller 220 includes a hub 221 and blades 222 disposed on the hub 221; the distal end of the hub 221 points toward the liquid outlet 102. As previously described, the delivery path of the blood pump 10 implanted in the pulmonary artery 26 generally runs from the inferior vena cava 20 or superior vena cava 21, sequentially through the right atrium 22, the tricuspid valve 23, the right ventricle 24, and the pulmonary valve 25, to the pulmonary artery 26, thereby assisting the right ventricle 24 in pumping blood to the pulmonary artery 26. Compared to the delivery path of the blood pump 10 implanted in the left ventricle from the aorta, the delivery path of the blood pump 10 implanted in the pulmonary artery 26 is shorter, has more tortuous paths, and has complex internal structures. During the process of implanting the pump body 11 of the blood pump 10 into the pulmonary artery 26, when the pump body 11 passes through multiple narrow bends in the push path of the pulmonary artery 26, the periphery of the liquid outlet 102 of the pump body 11 may hit the inner wall of the tissue at the bend, causing the inner wall of the tissue to be concave inward from the liquid outlet 102 and contact the distal end of the hub 221.

[0124] In view of the above situation, in order to prevent the distal end of the hub 221 from damaging the inner wall of the tissue, the diameter of the hub 221 can optionally be gradually increased along the direction from the impeller 220 to the liquid outlet 102. This configuration can increase the insensitivity of the distal end of the hub 221. During the implantation of the blood pump 10 into the patient's body, if the inner wall of the tissue is sunk from the liquid outlet 102 and contacts the distal end of the hub 221, due to the larger diameter of the distal end of the hub 221 of the impeller 220 of the present application, the insensitivity of the distal end of the hub 221 is stronger, and the contact area of ​​the distal end of the hub 221 with the inner wall of the tissue is also larger. The distal end surface of the hub 221 can disperse the mutual force between the hub 221 and the inner wall of the tissue, thereby making it less likely for the distal end of the hub 221 to scratch the inner wall of the tissue, thereby reducing the possibility of the distal end of the hub 221 damaging the inner wall of the tissue.

[0125] Furthermore, because the diameter of the hub 221 gradually increases from the impeller 220 to the liquid outlet 102, the spacing between the outer circumference of the hub 221 and the inner circumference of the pump housing 100 gradually decreases along the direction of the hub 221's diameter expansion. The diameter expansion direction is the direction from the impeller 220 to the liquid outlet 102. This arrangement allows the distal end of the hub 221 to have a larger diameter, resulting in a spacing K2 between the distal outer circumference of the hub 221 and the inner circumference of the pump housing 100 that is smaller than the spacing K1 between the proximal outer circumference of the hub 221 and the inner circumference of the pump housing 100, i.e., K2 < K1. Blood enters the impeller 220 at the interval K1 and is driven by the impeller 220 to rotate spirally, thereby being gradually pushed by the impeller 220 toward the interval K2. Since the path from the interval K1 to the interval K2 gradually becomes narrower, the blood is gradually compressed by the spiral during this process, so that the blood is driven by the impeller 220 to rotate spirally and obtains greater kinetic potential energy, thereby accelerating the blood to be discharged from the liquid outlet 102.

[0126] Referring to Figures 15, 16, and 17, the diameter of hub 221 gradually increases from impeller 220 to liquid outlet 102, resulting in a maximum hub diameter N at the distal end of hub 221. Optionally, the distal end surface of hub 221 is configured as a hemispherical surface 201, with the sphere containing hemispherical surface 201 having the maximum hub diameter N as its diameter. Assuming that the sphere containing hemispherical surface 201 is centered at O2, with R as its radius, and O2 located on central axis M1M2, then R = N / 2. This allows the distal end of hub 221 to be smoother. When the inner wall of tissue abuts the distal end of hub 221, it is less likely to be scratched by the distal end of hub 221.

[0127] It is understood that the drive unit 200 also includes a motor 210, which is connected to the impeller 220 to drive the impeller 220 to rotate. The motor 210 is fixedly connected to the proximal end of the pump housing 100 to form a part of the pump body 11. When the blood pump 10 is implanted in the patient's body, the motor 210 can be implanted in the patient's body together with the pump housing 100. In other embodiments, the motor 210 can also be configured outside the blood pump, that is, outside the body, and the motor 210 is connected to the impeller 220 via a flexible shaft that passes through the catheter 12 and the pump housing 100 in sequence. When the blood pump 10 is implanted in the patient's body, the motor 210 is not implanted in the patient's body along with the pump housing 100.

[0128] For example, in a blood pump 10 according to any of the above-described embodiments, the pump body 11 of the blood pump 10 can be clamped and fixed by the pulmonary valve 25. FIG24 shows a schematic diagram of the pump body 11 of the blood pump 10 of the present application being clamped and fixed by the pulmonary valve 25. The dotted arrow F in FIG24 represents the direction of blood flow. Referring to FIG24 , the pump body 11 of the blood pump 10 is generally fixed in the patient's body by partially passing the pump body 11 through the pulmonary valve 25 so that the pump body 11 is clamped and fixed by the pulmonary valve 25. The liquid inlet 101 of the pump body 11 is located in the right ventricle 24, while the liquid outlet 102 of the pump body 11 is located in the pulmonary artery 26. Blood in the right ventricle 24 can enter the pump body 11 of the blood pump 10 through the liquid inlet 101 and then be discharged to the pulmonary artery 26 through the liquid outlet 102 of the pump body 11.

[0129] However, the present application takes into account that the heart is always undergoing alternating contraction and expansion. When the heart 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, and the pump body 11 of the blood pump 10 tends to move into the pulmonary artery 26. Conversely, when the heart expands, the pulmonary valve 25 closes, and the pulmonary valve 25 tends to carry the pump body 11 of the blood pump 10 into the right ventricle 24. Because the right ventricular delivery path is short, has many bends, and has a complex internal structure, the axial length of the pump body 11 of the blood pump 10 of the present application is designed to be relatively short to enable the blood pump body to pass through the narrow bends of the right ventricular delivery path. If the present application still adopts the method of clamping and fixing the pump body 11 by the pulmonary valve 25, the pump body 11 with a shorter axial length is easily affected by the opening and closing movement of the pulmonary valve 25, making it very easy for the pump body 11 to loosen and fall off from the pulmonary valve 25.

[0130] In view of this, the present application also provides another way to fix the pump body 11 of the blood pump 10 to the patient's body. Specifically, referring to Figure 25, in one embodiment, the pump body 11 can be configured in the pulmonary artery 26; and fixed with the heart structure through the catheter 12 of the blood pump 10. The pump body 11 is not clamped by the pulmonary artery 26, so the pump body 11 is not easily affected by the movement of the pulmonary valve 25, fundamentally eliminating the possibility of the pump body 11 loosening and falling off the pulmonary valve 25. In addition, the pulmonary valve 25 is clamped in the catheter 12, and the diameter of the catheter 12 is smaller than the diameter of the pump body 11, so the reaction force on the pulmonary valve 25 is also small, which can reduce the damage to the pulmonary valve 25. When the blood pump 10 is working, the blood in the right ventricle 24 flows into the pulmonary artery 26 through the pulmonary valve 25, and is then sucked into the pulmonary artery 26 by the liquid inlet 101 of the blood pump 10 at the end close to the pulmonary valve 25. After being accelerated by the blood pump 10, the blood is discharged from the distal tube port 102 of the blood pump 10 to the end of the pulmonary artery 26 away from the pulmonary valve 25.

[0131] Generally speaking, the pulmonary artery 26 is short and thick. At its distal end (i.e., the end distal to the right ventricle 24), the pulmonary artery 26 branches into a left pulmonary artery 261 and a right pulmonary artery 262. When the pump body 11 is placed within the pulmonary artery 26, the outlet 102 of the pump body 11 is relatively close to the branching point of the pulmonary artery 26. Because the outlet 102 of the pump body 11 is flared, some of the blood discharged from the outlet 102 has the potential to be radially deflected. A portion of the blood F2 is radially deflected to the left and flows into the left pulmonary artery 261, while a portion of the blood F3 is radially deflected to the right and flows into the right pulmonary artery 262. Obviously, making the liquid outlet 102 of the pump body 11 into an expanded shape can help to divert the blood discharged from the liquid outlet 102 to the left pulmonary artery 261 and the right pulmonary artery 262, reduce the collision between the blood and the inner wall of the tissue at the branch of the pulmonary artery 26, and thereby reduce the kinetic energy loss of the blood discharged from the liquid outlet 102.

[0132] Referring to FIG. 25 , because the pump body 11 of the blood pump 10 of the present application is adapted for installation within the pulmonary artery 26 , the length of the pump body 11 needs to be relatively short. Therefore, in this embodiment, the pump body 11 has a first length L1 (see FIG. 2 or FIG. 14 ), which enables the pump body 11 to be entirely positioned within the pulmonary artery 26 . The blood pump 10 also includes a catheter 12 , which is affixed to the proximal end of the drive unit 200 and can be secured to the heart structure to position the pump body 11 within the pulmonary artery 26 .

[0133] Specifically, the first length L1 of the pump body 11 refers to the axial length of the pump body 11. This first length L1 enables the blood pump 10 to pass through the right atrium 22, right ventricle 24, and pulmonary valve 25 and be pushed into the pulmonary artery 26, ensuring that the entire pump body 11 is located within the pulmonary artery 26. In other words, the liquid inlet 101 and liquid outlet 102 of the pump body 11 are both located within the pulmonary artery 26, and the pump body 11 is not clamped by the pulmonary artery 26. The catheter 12 is fixed to the heart structure, thereby fixing the position of the catheter 12 and, consequently, positioning the pump body 11 within the pulmonary artery 26. The first length L1 of the pump body 11 must be able to adapt to both the delivery path of the right ventricle 24 and the physiological structure of the pulmonary artery 26, to facilitate implantation within the pulmonary artery 26.

[0134] It can be understood that the pulmonary artery 26 is short and thick, and the end of the pulmonary artery 26 (i.e., the end away from the right ventricle 24) branches out into the left pulmonary artery 261 and the left pulmonary artery 262. Since the pump body 11 is placed in the pulmonary artery 26, the first length L1 should not exceed 30 mm, that is, L1 ≤ 30 mm. Because if the first length L1 exceeds 30 mm, it may be difficult for the pump body 11 to pass through the various narrow bends of the push path of the right ventricle 24. Even if it can pass through the push path of the right ventricle 24, after the pump body 11 reaches the pulmonary artery as a whole, the distal end of the pump body 11 may hit the branch at the end of the pulmonary artery 26 due to the excessive length of the pump body 11. Therefore, the first length L1 should not exceed 30 mm.

[0135] It is understandable that the size or anatomical shape of the push path of the right ventricle 24 of different patients is slightly different. For example, the size or distance of the internal tissue of the push path of the right ventricle 24 of young patients and elderly patients are somewhat different, and the requirements for the first length L are also different. Therefore, in actual application, the length of the first length L1 should be set according to the actual situation of the patient. Optionally, the first length L1 is 20mm to 30mm, that is, 20mm≤L≤30mm. The first length L1 can be but is not limited to 22mm, 25mm, 28mm, 30mm, etc. It can be reasonably designed according to the characteristics of different patients such as age, body shape or symptoms.

[0136] Referring to Figure 25, a blood pump 10 such as any of the above-mentioned embodiments, the catheter 12 includes a proximal portion 12a, a distal portion 12b and a shaped portion 12c; wherein the distal portion 12b is fixedly connected to the drive unit 200, and the shaped portion 12c is adjacent to the distal portion 12b; the shape of the shaped portion 12c is predetermined to be consistent with the anatomical shape of the blood passage of the right ventricle 24 of the heart so as to be fixed in coordination with the heart structure; the blood passage is a communication path between the superior vena cava 21 or the inferior vena cava 20 and the right atrium 22, the right ventricle 24, and the pulmonary artery 26.

[0137] Specifically, the catheter 12 is used to accommodate the supply lines of the blood pump body 11, such as guide wires and flushing lines. The catheter 12 is an elastic structure and can undergo elastic deformation. When not subjected to external forces, the shaped portion 12c of the catheter 12 can maintain its curved initial shape, which is consistent with the anatomical shape of the blood passageway of the right ventricle 24 of the heart. When the blood pump 10 is implanted in the patient's body, the shaped portion 12c of the catheter 12 is elastically deformed by the squeezing force of the tissue inner wall of the blood passageway during the process of the catheter 12 passing through the blood passageway of the heart. This allows the catheter 12 to pass smoothly through the blood passageway until the pump body 11 of the blood pump 10 fully enters the predetermined position in the pulmonary artery 26. The shaped portion 12c of the catheter 12 then returns to its initial shape, thereby adapting and fixing to the anatomical shape of the blood passageway of the right ventricle 24 of the heart.

[0138] For ease of understanding, the communication path between the superior vena cava 21 and the right atrium 22, right ventricle 24, and pulmonary artery 26 is defined herein as the first blood pathway; and the communication path between the inferior vena cava 20 and the right atrium 22, right ventricle 24, and pulmonary artery 26 is defined as the second blood pathway. Referring to Figure 25 , in one embodiment, the shape of the shaped portion 12c of the catheter 12 is configured to match the shape of the first blood pathway. In this case, the delivery path of the blood pump 10 is as follows: the pump body 11 of the blood pump 10 passes sequentially through the superior vena cava 21, right atrium 22, tricuspid valve 23, right ventricle 24, pulmonary valve 25, and into the pulmonary artery 26. After the pump body 11 reaches a predetermined position within the pulmonary artery 26, the shaped portion 12c of the catheter 12 returns to its original shape. This shaped portion 12c is fixedly adapted to the shape of the first blood pathway, and is unlikely to move in the first blood pathway without external force.

[0139] Referring to Figure 26 , in another embodiment, the shape of the shaped portion 12c of the catheter 12 can also be configured to match the shape of the second blood pathway. In this case, the blood pump 10 pushes blood along a path where the pump body 11 of the blood pump 10 passes sequentially through the inferior vena cava 20, the right atrium 22, the tricuspid valve 23, the right ventricle 24, the pulmonary valve 25, and into the pulmonary artery 26. Once the pump body 11 reaches a predetermined position within the pulmonary artery 26, the shaped portion 12c of the catheter 12 returns to its original shape. This shaped portion 12c is fixedly adapted to the shape of the second blood pathway, and when not subjected to external forces, the shaped portion 12c of the catheter 12 is unlikely to move within the second blood pathway.

[0140] As described above, the entire pump body 11 of the blood pump 10 can be inserted into the pulmonary artery 26. However, due to the short and thick nature of the pulmonary artery 26, the pump body 11 should not be excessively long. Therefore, in this application, the outlet housing 300 is the distal-most component of the blood pump 10, meaning that the distal end of the outlet housing 300 is no longer connected to components such as a pigtail. This reduces the overall length of the pump body 11, ensuring that, after implantation, the pump body 11 can be fully accommodated within the pulmonary artery 26 and is less likely to impact with branches of the pulmonary artery 26.

[0141] The technical features of the above-described embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification. The above-described embodiments only express several implementation methods of the present application. The description is relatively specific and detailed, but it cannot be understood as a limitation on the scope of the patent application. For ordinary technicians in this field, without departing from the concept of the present application, several variations and improvements can be made, which all fall within the scope of protection of the present application. Therefore, the scope of protection of the patent application of this application shall be based on the attached claims.

Claims

1. A blood pump, characterized in that: The blood pump comprises a pump body, and the pump body comprises: A pump housing, wherein a liquid inlet is provided at a proximal end of the pump housing, and a distal end of the pump housing is open so that the distal end of the pump housing is set as a liquid outlet, and a central axis of the pump housing passes through the liquid outlet; a driving unit, the driving unit being fixedly connected to the proximal end of the pump housing, and the driving unit being capable of driving blood to flow from the liquid inlet to the liquid outlet; and A desensitizing ring is arranged along the periphery of the liquid outlet; the radial thickness of the desensitizing ring is greater than the tube wall thickness of the pump housing; the desensitizing ring is provided with a circular wall extending along its circumferential direction, and the center of the mother circle of the circular body where the circular wall is located is located inside the desensitizing ring.

2. The blood pump according to claim 1, characterized in that The insensitive ring is the farthest end of the blood pump; The pump body has a first length, which is 20 mm to 30 mm. The first length enables the pump body to be entirely located in the pulmonary artery.

3. The blood pump according to claim 1, characterized in that The annular wall of the insensitive ring includes a distal wall located at the farthest end of the insensitive ring, and the cross section of the distal wall cut by an axial plane is semicircular; wherein the axial plane is a plane passing through the central axis.

4. The blood pump according to claim 3, characterized in that The annular wall also includes at least one of the following features: The annular wall also includes an outer side wall located outside the insensitive ring, the cross section of the outer side wall cut by the axial plane is arc-shaped, and the outer side wall smoothly connects the distal wall and the outer peripheral surface of the pump housing; The annular wall also includes an inner wall located inside the insensitive ring, the cross section of the inner wall cut by the axial plane is arc-shaped, and the inner wall smoothly connects the distal wall and the inner circumference of the pump housing.

5. The blood pump according to claim 3, characterized in that The insensitive ring is configured as a circular ring, so that the insensitive ring itself serves as the circular ring where the circular ring wall is located; and two cross sections of the insensitive ring cut by any one of the axial planes are symmetrical about the central axis.

6. The blood pump according to claim 1, characterized in that The pump housing includes a housing tube fixedly connected to the drive unit, and an extension tube connected to the distal end of the housing tube; wherein the distal end of the extension tube is provided with a distal opening for forming the liquid outlet; the insensitive ring is connected to the periphery of the distal opening, and the insensitive ring constitutes the farthest end of the blood pump.

7. The blood pump according to claim 6, characterized in that The extension tube comprises a connection section fixedly connected to the shell tube, and a transition section connecting the connection section and the insensitive ring; the extension tube also has at least one of the following characteristics: The connecting section has a first inner diameter, and the insensitive ring has a second inner diameter, the second inner diameter is the minimum inner diameter of the insensitive ring, and the second inner diameter is smaller than the first inner diameter; The connecting section has a first outer diameter, and the insensitive ring has a second outer diameter, wherein the second outer diameter is the maximum outer diameter of the insensitive ring, and the second outer diameter is smaller than the first outer diameter; The transition section has a third inner diameter, and the third inner diameter is gradually reduced in the direction from the connecting section to the insensitive ring; The transition section has a third outer diameter, and the third outer diameter gradually decreases and then increases in the direction from the connecting section to the insensitive ring. An annular recess is formed on the outer side of the transition section.

8. The blood pump according to claim 6, characterized in that The extension tube includes a connecting section fixedly connected to the shell tube, and a transition section connecting the connecting section and the insensitive ring; a plurality of through holes are penetrated on the side wall of the transition section, and the through holes have a second length extending along the circumference of the extension tube; a partition wall is formed between two adjacent through holes; the partition wall has a third length extending along the circumference of the extension tube, and the third length is greater than or equal to the second length.

9. The blood pump according to claim 1, characterized in that: The driving unit comprises a motor and an impeller connected to the motor; the impeller is arranged inside the pump housing and is axially opposite to the liquid outlet; the impeller comprises a hub and blades arranged on the hub; the diameter of the hub is gradually increased along the direction from the motor to the impeller, so that the distal end of the hub has a fourth outer diameter, and the fourth outer diameter is the maximum diameter of the hub; The impeller has a fifth outer diameter, which is the maximum diameter of the impeller when it rotates as a whole; the insensitive ring has a second inner diameter, which is the minimum inner diameter of the insensitive ring, and the second inner diameter is larger than the fourth outer diameter and smaller than the fifth outer diameter.

10. The blood pump according to claim 1, characterized in that The driving unit comprises a motor and an impeller connected to the motor; the motor and the impeller are both arranged inside the pump housing, a blood flow channel is formed between the motor and the inner wall surface of the pump housing, and the blood flow channel connects the liquid outlet with the liquid inlet; the proximal end of the motor is fixedly connected to the proximal end of the pump housing; The motor includes a motor body and a shaft support seat connected to the distal end of the motor body, wherein 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; a rectifier plate is arranged on the conical guide surface, and a plurality of the rectifier plates are arranged at intervals along the circumference of the conical guide surface, and the plurality of the rectifier plates extend along the axial direction of the motor.

11. A blood pump, characterized in that: The blood pump comprises a pump body, and the pump body comprises: A pump housing, the pump housing comprising a main body section having a liquid inlet, and a reducing section connected to the main body section; A desensitizing ring, the desensitizing ring being arranged at the distal end of the diameter-changing section, the inner circumference of the desensitizing ring and the inner circumference of the diameter-changing section jointly defining a liquid outlet; a desensitizing wall being arranged at the distal end of the desensitizing ring, the desensitizing wall extending along the circumferential direction of the desensitizing ring, the radial width of the desensitizing wall along the radial direction of the pump housing being greater than the wall thickness of the pump housing; as well as A driving unit, wherein the driving unit comprises an impeller arranged in the pump housing, the impeller points to the liquid outlet, and the direction in which the impeller points to the liquid outlet is recorded as a first direction. The diameter of the liquid outlet gradually increases along the first direction so that the liquid outlet is in a flared shape.

12. The blood pump according to claim 11, characterized in that The insensitive ring is the farthest end of the blood pump. The pump body has a first length, which is 20 mm to 30 mm. The first length enables the pump body to be located entirely in the pulmonary artery.

13. The blood pump according to claim 11, characterized in that The inner circumference of the diameter-changing section has a first diameter, which gradually increases along the first direction; the outer circumference of the diameter-changing section has a second diameter, which gradually increases along the first direction.

14. The blood pump according to claim 13, characterized in that The tube wall thickness at the diameter-changing section is recorded as the first tube wall thickness, the first tube wall thickness is 1 / 2 times the difference between the second diameter and the first diameter, and the first tube wall thickness gradually increases along the first direction; or, The inner circumference of the variable diameter section is curved in an arc shape so as to be smoothly connected to the inner circumference of the insensitive wall. The outer circumference of the variable diameter section is curved in an arc shape so as to be smoothly connected to the outer circumference of the insensitive wall. The curvature of the inner circumference of the variable diameter section is greater than the curvature of the outer circumference of the variable diameter section. An annular recess is formed on the outer side of the outer circumference of the variable diameter section.

15. The blood pump according to claim 11, characterized in that The inner periphery of the insensitive wall is smoothly connected to the inner periphery of the variable diameter section to form a first connection; the outer periphery of the insensitive wall is smoothly connected to the outer periphery of the variable diameter section to form a second connection; the insensitive wall is curved in a convex arc shape from the first connection to the second connection.

16. The blood pump according to claim 15, characterized in that The outer circumferential surface of the main body segment has a third diameter; the insensitive wall has a radial section perpendicular to the central axis of the impeller, and the circular tangent formed by the insensitive wall and the radial section is recorded as the distal circumferential line, and the distal circumferential line has an inner diameter, and the inner diameter is greater than the third diameter.

17. The blood pump according to claim 16, characterized in that The radial distance between the distal circumference and the inner circumference of the main body section is recorded as the diameter expansion deviation; the axial distance from the starting end of the variable diameter section connected to the main body section to the radial section is recorded as the total outlet length, and the total outlet length is greater than the diameter expansion deviation; The ratio of the total outlet length to the diameter expansion deviation is 2.5 to 4.

5.

18. The blood pump according to claim 11, characterized in that The insensitive wall is located on the annular body, the center of the mother circle of the annular body is located inside the insensitive ring, and the diameter of the mother circle is the radial width of the insensitive ring; the distal circumference line of the insensitive wall divides the insensitive wall into an inner arc wall and an outer arc wall, the inner arc wall is located between the distal circumference line and the first connection, and the outer arc wall is located between the distal circumference line and the second connection; wherein, The inner arc wall has a first central angle, which is less than or equal to 90°; The outer arc wall has a second central angle, and the second central angle is greater than 90°.

19. The blood pump according to claim 18, characterized in that The insensitive wall has a highest point protruding along the radial direction relative to the outer circumference of the main body segment, and the highest point divides the outer arc wall into a first arc wall and a second arc wall, the first arc wall is located between the distal circumference line and the highest point, and the second arc wall is located between the highest point and the outer circumference of the diameter-changing segment; Furthermore, the distal end of the outer peripheral surface of the diameter-changing section has a first tangent line, and the second arc wall has a second tangent line at the second connection point, and the second tangent line coincides with the first tangent line.

20. The blood pump according to claim 11, characterized in that The wall thickness of the pump casing at the main body section is recorded as the second wall thickness; the height of the insensitive ring protruding in the radial direction relative to the outer peripheral surface of the main body section is recorded as the radial convex height, and the ratio of the radial convex height to the second wall thickness is 1.3 to 1.8; The pump housing includes a housing tube fixedly connected to the driving unit, and an extension tube connected to the distal end of the housing tube; wherein the diameter-reducing section and the insensitive ring are both arranged on the extension tube, and the extension tube is arranged as an elastic structure or a rigid structure.

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