An interventional ventricular assist device and ventricular assist membrane pump

Abstract

The present application relates to the field of medical equipment technology, and specifically to an interventional ventricular assist device and a ventricular assist membrane pump. The hardness range of the elastic diaphragm in the ventricular assist membrane pump is 50-80HA, and the elastic modulus range is 11-25Mpa, which makes the elastic diaphragm less ductile and not easily deformed by tension during repeated deformation of the elastic diaphragm. In order to meet the volume change requirements of the blood cavity, the elastic diaphragm can discharge the blood in the blood cavity and allow a set amount of blood to enter the blood cavity. The middle of the elastic diaphragm can bulge toward either side of the blood cavity and the medium cavity, thereby increasing the area of the elastic diaphragm, reducing or even eliminating the tension deformation of the elastic diaphragm, and making the diaphragm less prone to wrinkles. This improves the technical problem that the current diaphragm is prone to wrinkles after long-term tension deformation, resulting in a high risk of thrombosis.

Description

Technical Field

[0001] The present application relates to the technical field of medical equipment, and in particular to an interventional ventricular assist device and a ventricular assist membrane pump. Background Art

[0002] A percutaneous ventricular assist device (pVAD) can assist the heart or temporarily replace it when it fails. The device is typically inserted through the skin (percutaneously) into the femoral artery, for example, and then connected to the heart. It assists or takes over the heart's pumping function, increasing blood flow, enhancing blood perfusion, and reducing myocardial oxygen demand. It empties blood from the left ventricle and discharges it into the ascending aorta in sync with the cardiac cycle. It is commonly used in emergency situations, such as for short-term cardiac support during and after percutaneous coronary intervention (PCI) procedures for high-risk patients and those in cardiogenic shock. Therefore, the design of a pVAD prioritizes miniaturization, portability, and minimally invasiveness. Its key features are its small size, powerful functionality, and ease of operation. It allows for rapid intervention within a short timeframe, allowing patients with acute heart failure to quickly establish blood circulation and save valuable treatment time.

[0003] A percutaneous ventricular assist device typically includes a catheter, a ventricular assist membrane pump (VAPM), and a pumping unit. The catheter is inserted into the heart, and the VAPM chamber is divided into a medium chamber and a blood chamber by a diaphragm. The blood chamber connects to the catheter inserted into the body to receive blood pumped by the heart, while the medium chamber connects to the pumping unit to contain the fluid medium used to pump blood. When the heart is in systole, blood is pumped into the VAPM blood chamber through the catheter. The diaphragm deforms, allowing blood to occupy the blood chamber to the greatest extent possible, leaving almost no medium in the fluid medium chamber. When the heart is in diastole, the unit controls the filling of the medium chamber with fluid medium. As the medium continues to fill, the diaphragm gradually deforms in the opposite direction, pushing blood out of the VAPM and into the ascending aorta through a two-way valve at the proximal end of the catheter.

[0004] Current diaphragms are typically made of highly elastic materials. During ventricular assist membrane pump operation, the flexible diaphragm undergoes significant tensile deformation. Furthermore, the diaphragm must adapt to the pulsation, with the pumping frequency often reaching dozens or even hundreds of times per minute. This prolonged tensile deformation of the diaphragm can easily lead to wrinkles on the surface, increasing the risk of thrombosis. Summary of the Invention

[0005] The present application provides a ventricular assist membrane pump for improving the technical problem that the current diaphragm is prone to wrinkles after long-term tension deformation, resulting in a high risk of thrombosis.

[0006] The purpose of this application is also to provide an invasive ventricular assist device using the above-mentioned ventricular assist membrane pump.

[0007] In a first aspect, an embodiment provides a ventricular assist membrane pump, comprising:

[0008] a pump housing having a chamber therein;

[0009] and an elastic diaphragm, wherein the chamber is divided into a blood chamber and a medium chamber by the elastic diaphragm; the elastic diaphragm has a hardness range of 50-80HA and an elastic modulus range of 11-25Mpa;

[0010] The two sides of the elastic diaphragm in the thickness direction are respectively a first side and a second side, the blood cavity is on the first side, and the medium cavity is on the second side; when the pressure of the blood cavity is balanced with that of the medium cavity, the elastic diaphragm bulges toward one of the first side and the second side and is able to maintain this position; when the pressure of the blood cavity is greater than the pressure of the medium cavity, the elastic diaphragm bulges toward the second side, and when the pressure of the blood cavity is less than the pressure of the medium cavity, the elastic diaphragm bulges toward the first side.

[0011] Furthermore, in one embodiment, when the pressures of the blood chamber and the medium chamber are balanced, the minimum distance a between the apex of the bulged elastic diaphragm and the chamber is in the range of 0.6 mm ≤ a ≤ 2.61 mm.

[0012] Furthermore, in one embodiment, the pump housing has an inner wall surface of a blood chamber, and the inner wall surface of the blood chamber and the elastic diaphragm form the blood chamber, and the elastic diaphragm includes a fixed part and a movable part, and the movable part can bulge toward the first side or the second side; when the pressure of the blood chamber and the medium chamber is balanced and the elastic diaphragm bulges toward the first side, the minimum distance b between any point on the inner wall surface of the blood chamber and the movable part is in the range of: 0.6mm≤b≤2.61mm.

[0013] Furthermore, in one embodiment, the elastic diaphragm has a thickness ranging from 0.1 to 1.0 mm.

[0014] Furthermore, in one embodiment, the elastic diaphragm includes a membrane body and a blood cavity side coating, the blood cavity side coating is located on the side of the membrane body facing the blood cavity, and the blood cavity side coating is a hydrophilic coating, a hydrophobic coating or an anticoagulant coating.

[0015] Furthermore, in one embodiment, the pump housing includes a first shell and a second shell, the first shell having a blood channel connected to the blood chamber, the blood channel being used to allow blood to flow in and out of the blood chamber; the second shell also having a medium channel connected to the medium chamber, the medium channel being used to allow fluid medium to flow in and out of the medium chamber; the second shell having an annular protrusion protruding toward the blood chamber, an annular channel being formed between the annular protrusion and the inner wall surface of the first shell, the blood channel having a blood chamber connecting port, the blood chamber connecting port being located on the inner wall surface of the blood chamber; at least a portion of the blood chamber connecting port extends to the channel wall of the annular channel, so that the blood channel is directly connected to the annular channel.

[0016] Furthermore, in one embodiment, the first shell and the second shell are arranged along a first direction, the first shell has a central axis extending along the first direction, the centerline of the blood channel is coplanar with the central axis and is on a first plane, the blood cavity communication port is symmetrical about the first plane, and the blood channel smoothly transitions to the inner wall surface of the first shell.

[0017] Furthermore, in one embodiment, a second plane passes through the center line of the blood channel and is perpendicular to the first plane, a line where the inner wall of the first shell intersects the second plane is a first circle, the first circle is tangent to the channel wall of the blood channel at a first point and a second point, the radius of the first circle is d / 2, and the distance c between the first point and the second point satisfies: 2d / 25<c<4d / 5.

[0018] Furthermore, in one embodiment, the first shell and the second shell are arranged along a first direction, the first shell has a central axis extending along the first direction, the centerline of the blood channel is coplanar with the central axis and is on a first plane, the second plane passes through the centerline of the blood channel and is perpendicular to the first plane, the projected area of the inner wall surface of the first shell on the second plane is S1, the minimum flow area of the blood channel is S2, and the ratio of S1 / S2 ranges from 25 to 225.

[0019] Furthermore, in one embodiment, an edge of the elastic diaphragm is fixed to a side of the annular protrusion facing away from the medium cavity.

[0020] Furthermore, in one embodiment, the first shell and the second shell are arranged along a first direction, the first shell has a central axis extending along the first direction, the central axis is not coplanar with the center line of the blood channel, and the center line of the blood channel is on a second plane and the second plane is perpendicular to the central axis, the line where the inner wall surface of the first shell intersects the second plane is a first circle, a line where the channel wall surface of the blood channel intersects the second plane is a first straight line, and the other line is a curve, and the first straight line is tangent to the first circle.

[0021] In a second aspect, an embodiment provides an invasive ventricular assist device, comprising a catheter and a ventricular assist membrane pump, wherein the catheter is adapted to be connected to a human body and communicate with the blood cavity; the ventricular assist membrane pump comprises:

[0022] a pump housing having a chamber therein;

[0023] and an elastic diaphragm, wherein the chamber is divided into a blood chamber and a medium chamber by the elastic diaphragm; the elastic diaphragm has a hardness range of 50-80HA and an elastic modulus range of 11-25Mpa;

[0024] The two sides of the elastic diaphragm in the thickness direction are respectively a first side and a second side, the blood cavity is on the first side, and the medium cavity is on the second side; when the pressure of the blood cavity is balanced with that of the medium cavity, the elastic diaphragm bulges toward one of the first side and the second side and is able to maintain this position; when the pressure of the blood cavity is greater than the pressure of the medium cavity, the elastic diaphragm bulges toward the second side, and when the pressure of the blood cavity is less than the pressure of the medium cavity, the elastic diaphragm bulges toward the first side.

[0025] Furthermore, in one embodiment, when the pressures of the blood chamber and the medium chamber are balanced, the minimum distance a between the apex of the bulged elastic diaphragm and the chamber is in the range of 0.6 mm ≤ a ≤ 2.61 mm.

[0026] Furthermore, in one embodiment, the pump housing has an inner wall surface of a blood chamber, and the inner wall surface of the blood chamber and the elastic diaphragm form the blood chamber, and the elastic diaphragm includes a fixed part and a movable part, and the movable part can bulge toward the first side or the second side; when the pressure of the blood chamber and the medium chamber is balanced and the elastic diaphragm bulges toward the first side, the minimum distance b between any point on the inner wall surface of the blood chamber and the movable part is in the range of: 0.6mm≤b≤2.61mm.

[0027] Furthermore, in one embodiment, the elastic diaphragm has a thickness ranging from 0.1 to 1.0 mm.

[0028] Furthermore, in one embodiment, the elastic diaphragm includes a membrane body and a blood cavity side coating, the blood cavity side coating is located on the side of the membrane body facing the blood cavity, and the blood cavity side coating is a hydrophilic coating, a hydrophobic coating or an anticoagulant coating.

[0029] Furthermore, in one embodiment, the pump housing includes a first shell and a second shell, the first shell having a blood channel connected to the blood chamber, the blood channel being used to allow blood to flow in and out of the blood chamber; the second shell also having a medium channel connected to the medium chamber, the medium channel being used to allow fluid medium to flow in and out of the medium chamber; the second shell having an annular protrusion protruding toward the blood chamber, an annular channel being formed between the annular protrusion and the inner wall surface of the first shell, the blood channel having a blood chamber connecting port, the blood chamber connecting port being located on the inner wall surface of the blood chamber; at least a portion of the blood chamber connecting port extends to the channel wall of the annular channel, so that the blood channel is directly connected to the annular channel.

[0030] Furthermore, in one embodiment, the first shell and the second shell are arranged along a first direction, the first shell has a central axis extending along the first direction, the centerline of the blood channel is coplanar with the central axis and is on a first plane, the blood cavity communication port is symmetrical about the first plane, and the blood channel smoothly transitions to the inner wall surface of the first shell.

[0031] Furthermore, in one embodiment, a second plane passes through the center line of the blood channel and is perpendicular to the first plane, a line where the inner wall of the first shell intersects the second plane is a first circle, the first circle is tangent to the channel wall of the blood channel at a first point and a second point, the radius of the first circle is d / 2, and the distance c between the first point and the second point satisfies: 2d / 25<c<4d / 5.

[0032] Furthermore, in one embodiment, the first shell and the second shell are arranged along a first direction, the first shell has a central axis extending along the first direction, the centerline of the blood channel is coplanar with the central axis and is on a first plane, the second plane passes through the centerline of the blood channel and is perpendicular to the first plane, the projected area of the inner wall surface of the first shell on the second plane is S1, the minimum flow area of the blood channel is S2, and the ratio of S1 / S2 ranges from 25 to 225.

[0033] Furthermore, in one embodiment, an edge of the elastic diaphragm is fixed to a side of the annular protrusion facing away from the medium cavity.

[0034] Furthermore, in one embodiment, the first shell and the second shell are arranged along a first direction, the first shell has a central axis extending along the first direction, the central axis is not coplanar with the center line of the blood channel, and the center line of the blood channel is on a second plane and the second plane is perpendicular to the central axis, the line where the inner wall surface of the first shell intersects the second plane is a first circle, a line where the channel wall surface of the blood channel intersects the second plane is a first straight line, and the other line is a curve, and the first straight line is tangent to the first circle.

[0035] According to the ventricular assist membrane pump of the above-described embodiment, the elastic diaphragm in the ventricular assist membrane pump has a hardness range of 50-80 HA and an elastic modulus range of 11-25 MPa. This results in low ductility of the elastic diaphragm, making it less susceptible to tensile deformation during repeated deformation. To meet the volumetric change requirements of the blood cavity, the elastic diaphragm can expel blood from the blood cavity while simultaneously allowing a set amount of blood to enter the blood cavity. The center of the elastic diaphragm can bulge toward either the blood cavity or the medium cavity. This increases the area of the elastic diaphragm, reduces or even eliminates tensile deformation of the elastic diaphragm, and makes the diaphragm less susceptible to wrinkling. This improves the technical problem of existing diaphragms that are prone to wrinkling after prolonged tensile deformation, resulting in a high risk of thrombosis. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 is a schematic structural diagram of an invasive ventricular assist device in an embodiment;

[0037] Figure 2 A schematic diagram of the structure of a ventricular assist membrane pump in an embodiment;

[0038] Figure 3 A schematic diagram of a state in which the elastic diaphragm of a ventricular assist membrane pump bulges toward a first side in an embodiment;

[0039] Figure 4 A schematic diagram of a state in which the elastic diaphragm of a ventricular assist membrane pump bulges toward the second side in one embodiment;

[0040] Figure 5 A top view of a ventricular assist membrane pump according to an embodiment;

[0041] Figure 6 For the Figure 5 Cross-sectional view of AA;

[0042] Figure 7 A front view of a ventricular assist membrane pump in one embodiment;

[0043] Figure 8 For the Figure 7 Cross-sectional view of the middle BB;

[0044] Figure 9 is a structural diagram of a ventricular assist membrane pump in another embodiment;

[0045] Figure 10 for Figure 8 The scheme shown in Figure 9 Comparison of pump blood flow rates for the schemes shown in ;

[0046] Figure 11 for Figure 8 The scheme shown in Figure 9 Comparison of maximum shear stress on the pump wall for the schemes shown in .

[0047] List of feature names corresponding to the reference numerals in the figure: 100, ventricular assist membrane pump; 200, catheter; 201, window; 202, two-way valve; 300, pumping main unit; 1, pump housing; 11, chamber; 111, blood chamber; 1111, blood chamber inner wall; 1112, annular channel; 112, medium chamber; 12, first housing; 121, blood channel; 1211, blood chamber connecting port; 1212, center line; 122, center Axis; 13. Second shell; 131. Annular protrusion; 1311. Protrusion side; 132. Medium channel; 14. Conduit connector; 15. Host connector; 16. First plane; 17. Second plane; 18. First circle; 19. First point; 101. Second point; 102. First straight line; 2. Elastic diaphragm; 21. First side; 22. Second side; 23. Vertex; 24. Fixed part; 25. Moving part; 3. Fixed ring.

[0048] Explanation of the reference numerals in brackets in the accompanying drawings: In the reference numerals in brackets in the accompanying drawings, the features referred to by the reference numerals are both the features represented by the numbers in the brackets and the features represented by the numbers outside the brackets. DETAILED DESCRIPTION

[0049] The present application is further described in detail below by means of specific embodiments in conjunction with the accompanying drawings. Similar elements in different embodiments are numbered with associated similar elements. In the following embodiments, many detailed descriptions are provided to enable the present application to be better understood. However, those skilled in the art will readily appreciate that some of the features may be omitted in different circumstances, or may be replaced by other elements, materials, or methods. In some cases, some operations related to the present application are not shown or described in the specification. This is to avoid the core portion of the present application being overwhelmed by excessive descriptions. For those skilled in the art, it is not necessary to describe these related operations in detail. They can fully understand the related operations based on the description in the specification and the general technical knowledge in the art.

[0050] In addition, the features, operations, or characteristics described in the specification may be combined in any appropriate manner to form various embodiments. Furthermore, the steps or actions in the method description may be reordered or adjusted in a manner readily apparent to those skilled in the art. Therefore, the various sequences in the specification and drawings are provided solely for the purpose of clearly describing a particular embodiment and are not intended to be mandatory, unless otherwise specified.

[0051] In the description of this document, it should be understood that 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" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on this application.

[0052] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or to implicitly indicate the quantity of the technical features indicated. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the features.

[0053] In this application, unless otherwise expressly specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection, abutment, or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0054] In this application, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Furthermore, when a first feature is "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 "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.

[0055] The various embodiments described in the specific implementation manner can be combined in any suitable manner without contradiction. For example, different implementation manners can be formed by combining different embodiments. In order to avoid unnecessary repetition, various possible combinations of the embodiments will not be described separately.

[0056] Although the diaphragm with high compliance has better elasticity, after the ventricular assist membrane pump has been running for a long time, the diaphragm is prone to fatigue, and after being stretched and deformed, it is easy to produce wrinkles, and blood clots are easy to accumulate on the surface of the diaphragm. In addition, the diaphragm in the prior art has strong compliance and high elasticity, but when it responds to the fluid medium to push the blood out, the elasticity of the diaphragm itself will also bring a certain resistance to the medium push, affecting the instantaneous flow rate of the blood. The present application provides a ventricular assist membrane pump, the elastic diaphragm of the ventricular assist membrane pump has low compliance, and the deformation capacity of the elastic diaphragm is compensated by increasing the area of the elastic diaphragm. Under the condition of meeting the use requirements, the elastic diaphragm has little or no stretch deformation, is not easy to produce wrinkles, and reduces the risk of blood clots formed due to wrinkles. The ventricular assist membrane pump and the interventional ventricular assist device in this application are introduced in detail below with reference to the accompanying drawings.

[0057] For some examples, please refer to Figures 1 to 4 The interventional ventricular assist device includes a ventricular assist membrane pump 100 and a catheter 200. The ventricular assist membrane pump 100 includes a pump housing 1 and an elastic diaphragm 2. The pump housing 1 has a chamber 11, and the chamber 11 is divided into a blood chamber 111 and a medium chamber 112 by the elastic diaphragm 2.

[0058] The elastic diaphragm 2 has a hardness range of 50-80 HA and an elastic modulus range of 11-25 MPa. The elastic diaphragm 2 has a first side 21 and a second side 22 along its thickness direction, with the blood chamber 111 located on the first side 21 and the medium chamber 112 located on the second side 22. When the pressures in the blood chamber 111 and the medium chamber 112 are balanced, the elastic diaphragm 2 bulges toward one of the first side 21 and the second side 22 and maintains this position. Maintaining the bulged elastic diaphragm 2 reduces the risk of thrombosis due to redundant area and stacking of the elastic diaphragm 2. When the pressure in the blood chamber 111 is greater than that in the medium chamber 112, the elastic diaphragm 2 bulges toward the second side 22. When the pressure in the blood chamber 111 is less than that in the medium chamber 112, the elastic diaphragm 2 bulges toward the first side 21.

[0059] In the ventricular assist membrane pump 100 of the present application, the elastic diaphragm 2 has a larger area, resulting in less or no tensile deformation during operation. This reduces tensile deformation, improves the durability of the elastic diaphragm 2, and makes it less likely to wrinkle due to tensile deformation. Furthermore, the hardness and elastic modulus of the elastic diaphragm 2 of the present application ensure that the diaphragm 2 maintains a unilateral bulge when pressure is balanced, forming a cup-like shape. This makes the diaphragm 2 less likely to collapse and less likely to form blood clots.

[0060] Since the low-compliance elastic diaphragm 2 of the present application has a larger surface area, during the process of injecting pressure medium into the medium cavity 112, the blood cavity 111 can respond more quickly to the pressure of the elastic diaphragm 2, and the blood in the blood cavity 111 can obtain a larger instantaneous flow rate, thereby reducing the accumulation of blood in the blood cavity 111.

[0061] Further, in one embodiment, please refer to Figure 3 and Figure 4 When the pressures in the blood chamber 111 and the medium chamber 112 are balanced, the minimum distance a between the apex 23 of the bulged elastic diaphragm 2 and the chamber 11 is in the range of 0.6 mm ≤ a ≤ 2.61 mm. Specifically, a can be selected from values such as 0.6 mm, 0.8 mm, 1 mm, 1.2 mm, 1.3 mm, 1.6 mm, 1.5 mm, 2 mm, 2.1 mm, 2.3 mm, and 2.6 mm.

[0062] For some examples, please refer to Figure 3 The pump housing 1 has a blood chamber inner wall surface 1111, which is capable of contacting the blood in the blood chamber 111. The blood chamber inner wall surface 1111 and the elastic diaphragm 2 enclose the blood chamber 111. The elastic diaphragm 2 includes a fixed portion 24 and a movable portion 25. The movable portion 25 is capable of bulging toward the first side 21 or the second side 22. When the pressure in the blood chamber 111 and the medium chamber 112 is balanced, and the elastic diaphragm 2 bulges toward the first side 21, the minimum distance b between any point on the blood chamber inner wall surface 1111 and the movable portion 25 is in the range of 0.6 mm ≤ b ≤ 2.61 mm. Specifically, b can be selected from values such as 0.6 mm, 0.8 mm, 1 mm, 1.2 mm, 1.3 mm, 1.6 mm, 1.5 mm, 2 mm, 2.1 mm, 2.3 mm, and 2.6 mm. The elastic diaphragm 2 is almost in contact with the inner wall surface 1111 of the blood cavity, and the closest distance between the elastic diaphragm 2 and the inner wall surface 1111 of the blood cavity has an appropriate value range, thereby preventing the elastic diaphragm 2 from affecting blood flow or pressure transmission due to its own tension.

[0063] In some embodiments, the thickness of the elastic membrane 2 is in the range of 0.1-1.0 mm. Specifically, the thickness of the elastic membrane can be in the range of 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm or 1.0 mm.

[0064] In one embodiment, the elastic membrane 2 is integrally injection molded. In some other embodiments, the elastic membrane 2 can also be extrusion-stretched.

[0065] Regarding the material of the elastic diaphragm 2, in one embodiment, the elastic diaphragm 2 is made of silicone material. In some other embodiments, the elastic diaphragm 2 can also be made of TPU material.

[0066] In some embodiments, the elastic diaphragm 2 includes a membrane body and a blood cavity side coating. The blood cavity side coating is located on the side of the membrane body facing the blood cavity 111 and can be a hydrophilic coating, a hydrophobic coating, or an anticoagulant coating. The side of the elastic diaphragm 2 facing the blood cavity 111 needs to be in contact with blood. The hydrophilic coating or the hydrophobic coating can reduce blood flow resistance, allowing blood to quickly reflux and accelerate blood exchange. The anticoagulant coating can directly reduce the probability of thrombosis and reduce the risk of harm to the patient.

[0067] Specifically, in some embodiments, the material for the blood-cavity coating is PVP, a zwitterionic polymer, a fluororesin, a superhydrophobic MOF, or a heparin complex. Specifically, materials that can be used for the hydrophilic coating include PVP (polyvinyl pyrrolidone), zwitterionic polymers (sulfobetaine SBMA, carboxymethyl chitosan CMC). Materials that can be used for the hydrophobic coating include fluororesins (such as PTFE, FEP), and superhydrophobic MOF. Materials that can be used for the anticoagulant coating include heparin complexes and zwitterionic polymers (phosphorylcholine, sulfobetaine microgel).

[0068] For some examples, please refer to Figures 1 to 6 The pump housing 1 includes a first housing 12 and a second housing 13. The first housing 12 has a blood channel 121 communicating with the blood chamber 111. The blood channel 121 is used to allow blood to enter and exit the blood chamber 111. The second housing 13 also has a medium channel 132 communicating with the medium chamber 112. The medium channel 132 is used to allow fluid medium to enter and exit the medium chamber 112. In one embodiment, the pump housing 1 includes a catheter connector 14 and a host connector 15. At least a portion of the blood channel 121 is located in the catheter connector 14, and at least a portion of the medium channel 132 is located in the host connector 15. The catheter connector 14 is connected to the catheter 200, and the host connector 15 is used to communicate with the pumping host 300. The pumping host 300 is used to pump fluid medium into the medium chamber 112, and is also used to extract fluid medium from the medium chamber.

[0069] For some examples, please refer to Figure 3 、 Figure 4 and Figure 6 The second housing 13 has an annular protrusion 131 projecting toward the blood chamber 111. An annular channel 1112 is formed between the annular protrusion 131 and the inner wall of the first housing 12. The blood channel 121 has a blood chamber communication port 1211 located on the blood chamber inner wall 1111. At least a portion of the blood chamber communication port 1211 extends to the channel wall of the annular channel 1112, allowing the blood channel 121 to directly communicate with the annular channel 1112. Blood in the blood chamber is pushed out by the elastic diaphragm 2 and flows into the annular channel 1112, which then communicates with the blood chamber communication port 1211. This reduces blood retention and prevents thrombosis.

[0070] For some examples, please refer to Figure 3 and Figure 4 The edge of the elastic diaphragm 2 is the fixing portion 24, and the fixing portion 24 is fixed to the annular protrusion 131. In some embodiments, the fixing portion 24 is fixed to the side of the annular protrusion 131 facing away from the medium cavity 112. For example, the fixing portion 24 can be fixed to the convex side surface 1311 of the annular protrusion 131 facing away from the medium cavity 112, and the fixing method can be adhesive. For another example, please refer to Figure 6 The fixing portion 24 can also be fixed in the annular channel 1112 via the fixing ring 3. This prevents the elastic diaphragm 2 from being too close to the inner wall 1111 of the blood chamber when it bulges toward the first side 21, thereby reducing the formation of blood clots. In one embodiment, the elastic diaphragm 2 is bonded to the annular protrusion 131.

[0071] In one embodiment, please refer to Figure 6 The first housing 12 and the second housing 13 are arranged along a first direction. The first housing 12 has a central axis 122 extending along the first direction. The centerline 1212 of the blood channel 121 is coplanar with the central axis 122 of the first housing 12 and lies on the first plane 16. The blood cavity communication opening 1211 is symmetrical about the first plane 16. This facilitates blood in the blood cavity to flow into the blood channel 121, reducing blood residue in the blood cavity.

[0072] When blood needs to be discharged from the blood cavity, the elastic diaphragm 2 is pushed toward the blood cavity 111. Since there is a certain distance between the elastic diaphragm 2 and the inner wall surface of the first shell 12, the remaining blood is discharged and flows into the annular channel 1112. The annular channel 1112 is connected to the blood cavity communication port 1211, so that the blood can flow out of the blood cavity 111 as much as possible.

[0073] Further, in one embodiment, please refer to Figures 6 to 8Second plane 17 passes through centerline 1212 of blood channel 121 and is perpendicular to first plane 16. The intersection of the inner wall of first housing 12 and second plane 17 forms first circle 18. First circle 18 is tangent to the wall of blood channel 121 at first point 19 and second point 101. The radius of first circle 18 is d / 2. The distance c between first point 19 and second point 101 satisfies the following: 2d / 25 < c < 4d / 5. Specifically, c can be 2d / 25, d / 5, d / 3, d / 2, 3d / 5, or 4d / 5.

[0074] In another embodiment of this application, please refer to Figure 9 The centerline 1212 of the blood channel 121 is not coplanar with the central axis 122 of the first housing 12, and the blood cavity communication opening 1211 is asymmetrical. A second plane 17 passes through the centerline 1212 of the blood channel 121 and is perpendicular to the central axis 122. The intersection of the inner wall of the first housing 12 and the second plane 17 forms a first circle 18. One line where the channel wall of the blood channel 121 intersects the second plane 17 is a first straight line 102, and another line is a curve. The curve includes an arc tangent to the first circle 18. The distance i between the points where the first straight line 102 and the arc tangent to the first circle 18 is in the range of d / 10 < i < d / 2. The tangency of the first straight line 102 to the first circle 18 facilitates blood flow out of the annular channel 1112.

[0075] In one embodiment, Figure 8 The solution of the symmetrical blood cavity communication port 1211 is Solution 1. Figure 9 The scheme of the asymmetric blood cavity communication port 1211 is scheme 2. The simulation analysis of schemes 1 and 2 is carried out. Figure 10 and Figure 11 , the blood flow rate of the blood cavity pump in Scheme 1 is higher than that in Scheme 2, and the maximum shear stress of the pump wall in Scheme 1 is less than the maximum shear stress of the pump wall in Scheme 2.

[0076] In one embodiment, to further increase the blood flow rate of the blood channel 121, the projected area of the inner wall of the first housing 12 on the second plane 17 is S1, the minimum flow area of the blood channel 121 is S2, and the ratio S1 / S2 ranges from 25 to 225. Specifically, the ratio S1 / S2 can be 25, 50, 100, 150, or 225.

[0077] In one embodiment, the cross-section of the blood channel 121 is circular. The minimum flow area of the blood channel 121 is defined as the area after the blood cavity communication port 1211 is left and the tube diameter no longer changes. In one embodiment, the first housing 12 has a housing opening opposite the second housing. The intersection of a cross-section of the first housing 12 perpendicular to the first direction and the inner wall of the first housing 12 is a circle, with the diameter of the circle gradually decreasing from the housing opening to the direction away from the housing opening. The ratio of the inner diameter of the housing opening to the minimum diameter of the blood channel is in the range of 5-25.

[0078] Regarding the structure of the catheter 200, in some embodiments, please refer to Figure 1 A window 201 is provided at the front end of the catheter 200, and a two-way valve 202 is provided on the rear side of the window 201. The two-way valve 202 is opened only when the ventricular assist membrane pump 100 pushes blood into the catheter 200, thereby establishing a passage between the inside of the catheter 200 and the ascending aorta.

[0079] For some examples, please refer to Figures 1 to 4 The steps for interventional ventricular assist device operation are:

[0080] For patients requiring ventricular assist, a femoral artery is punctured, and a guidewire is used to guide a catheter 200 equipped with a two-way valve 202 into the patient's aorta. The window 201 at the front of the catheter 200 is located within the left ventricle, while the two-way valve 202 is located outside the heart, in the ascending aorta. Once the catheter 200 is filled with blood, the catheter 200, an external ventricular assist membrane pump 100, and an external pumping unit 300 are connected. The pumping unit 300 pushes the fluid medium in sync with the heart rate, thereby pumping blood.

[0081] Specifically, during the heart's systole, the pumping unit 300 draws fluid from the medium chamber 112. Blood in the heart enters the catheter 200 through the window 201 at the front end of the catheter 200, and then into the blood chamber 111 of the ventricular assist membrane pump 100. Under the negative pressure of the medium chamber 112, the elastic diaphragm 2 deforms toward the medium chamber 112. During the heart's diastole, the pumping unit 300 pumps fluid into the medium chamber 112 of the ventricular assist membrane pump 100. At this point, the fluid (which can be liquid or gas) gradually fills the medium chamber 112, and the elastic diaphragm 2 is also deformed, pushing the blood in the blood chamber 111 into the catheter 200. The pushed blood flows through the two-way valve 202 into the ascending aorta. The ventricular assist membrane pump 100 pumps back and forth once per heartbeat. The pumping unit 300 controls the pushing of fluid based on the patient's heart rate, thereby assisting the ventricle in pumping blood.

[0082] In some embodiments of the ventricular assist membrane pump, the structure of the ventricular assist membrane pump is the same as the structure of the ventricular assist membrane pump 100 described in any of the above embodiments, and will not be described in detail.

[0083] The above specific examples are used to illustrate the present application, which is only used to help understand the present application and is not intended to limit the present application. For those skilled in the art of the present application, based on the concept of the present application, they can also make some simple deductions, modifications or substitutions.

Claims

1. A ventricular assist membrane pump, characterized in that: include: a pump housing having a chamber therein; and an elastic diaphragm, wherein the chamber is divided into a blood chamber and a medium chamber by the elastic diaphragm; The elastic diaphragm has two sides in a thickness direction, namely a first side and a second side, with the blood cavity being located on the first side and the medium cavity being located on the second side. The elastic diaphragm has a hardness range of 50-80 HA and an elastic modulus range of 11-25 MPa, so that when the pressures of the blood cavity and the medium cavity are balanced, the elastic diaphragm bulges toward one of the first side and the second side and maintains this balance. When the pressure of the blood cavity is greater than the pressure of the medium cavity, the elastic diaphragm bulges toward the second side, and when the pressure of the blood cavity is less than the pressure of the medium cavity, the elastic diaphragm bulges toward the first side. When the pressures of the blood chamber and the medium chamber are balanced, the minimum distance a between the apex of the bulged elastic diaphragm and the chamber is in the range of 0.6 mm ≤ a ≤ 2.61 mm.

2. The ventricular assist membrane pump according to claim 1, wherein The pump housing has an inner wall surface of a blood cavity, the inner wall surface of the blood cavity and the elastic diaphragm enclose the blood cavity, the elastic diaphragm includes a fixed part and a movable part, and the movable part can bulge toward the first side or the second side; When the pressures of the blood chamber and the medium chamber are balanced and the elastic diaphragm bulges toward the first side, a minimum distance b between any point on the inner wall of the blood chamber and the movable part is in the range of 0.6 mm ≤ b ≤ 2.61 mm.

3. The ventricular assist membrane pump according to claim 1 or 2, wherein: The thickness of the elastic diaphragm is in the range of 0.1-1.0 mm.

4. The ventricular assist membrane pump according to claim 1 or 2, wherein: The elastic diaphragm includes a membrane body and a blood cavity side coating. The blood cavity side coating is located on the side of the membrane body facing the blood cavity. The blood cavity side coating is a hydrophilic coating, a hydrophobic coating or an anticoagulant coating.

5. The ventricular assist membrane pump according to claim 1 or 2, wherein: The pump housing includes a first housing and a second housing, the first housing having a blood channel communicating with the blood chamber, the blood channel being used for allowing blood to flow into and out of the blood chamber; The second housing further comprises a medium passage communicating with the medium cavity, wherein the medium passage is used for allowing fluid medium to enter and exit the medium cavity; The second shell has an annular protrusion protruding toward the blood cavity, an annular channel is formed between the annular protrusion and the inner wall surface of the first shell, and the blood channel has a blood cavity communication port, and the blood cavity communication port is located on the inner wall surface of the blood cavity; At least a portion of the blood cavity communication port extends to the channel wall of the annular channel, so that the blood channel is directly connected to the annular channel.

6. The ventricular assist membrane pump according to claim 5, wherein: The first shell and the second shell are arranged along a first direction, the first shell has a central axis extending along the first direction, the centerline of the blood channel is coplanar with the central axis and is on a first plane, the blood cavity communication port is symmetrical about the first plane, and the channel wall of the blood channel smoothly transitions with the inner wall of the first shell.

7. The ventricular assist membrane pump according to claim 6, wherein: The second plane passes through the center line of the blood channel and is perpendicular to the first plane. The line where the inner wall of the first shell intersects the second plane is a first circle. The first circle is tangent to the channel wall of the blood channel at a first point and a second point. The radius of the first circle is d / 2, and the distance c between the first point and the second point satisfies the following: 2d / 25<c<4d / 5.

8. The ventricular assist membrane pump according to claim 5, wherein: The first shell and the second shell are arranged along a first direction, the first shell has a central axis extending along the first direction, the centerline of the blood channel is coplanar with the central axis and is on a first plane, the second plane passes through the centerline of the blood channel and is perpendicular to the first plane, the projected area of the inner wall surface of the first shell on the second plane is S1, the minimum flow area of the blood channel is S2, and the ratio of S1 / S2 ranges from 25 to 225.

9. The ventricular assist membrane pump according to claim 5, wherein: The edge of the elastic diaphragm is fixed on a side of the annular protrusion facing away from the medium chamber.

10. The ventricular assist membrane pump according to claim 5, wherein The first shell and the second shell are arranged along a first direction, the first shell has a central axis extending along the first direction, the central axis is not coplanar with the center line of the blood channel, and the center line of the blood channel is on a second plane and the second plane is perpendicular to the central axis, the line where the inner wall of the first shell intersects the second plane is a first circle, a line where the channel wall of the blood channel intersects the second plane is a first straight line, and the other line is a curve, and the first straight line is tangent to the first circle.

11. An interventional ventricular assist device, characterized in that: It comprises a catheter and a ventricular assist membrane pump as described in any one of claims 1 to 10, wherein the catheter is used to be connected to a human body and communicated with the blood cavity.

Images