Catheter pump

Abstract

A catheter pump (1), comprising: a catheter (10); a foldable pump head (30), which comprises a pump housing and a covering film (32) mounted on the pump housing, wherein the pump housing contains an impeller (34) therein and is mounted to a distal end of the catheter (10); and a drive shaft (50), which is rotationally arranged inside the catheter (10) and is connected to the impeller (34). The catheter (10) comprises: a first section (12), which is located inside the covering film (32); a second section (14), which is located near a proximal end of the covering film (32) and is continuous with the first section (12) towards a proximal end of the catheter; and a third section (16), which is continuous with the second section towards the proximal end of the catheter, wherein the stiffness of the first section is less than the stiffness of the second section, and the stiffness of the second section is less than the stiffness of the third section. By means of the provision of the three sections with varying stiffness, the cornering capacity of the catheter during intervention can be improved, and an accumulation caused by deformation of the covering film can also be effectively prevented.

Description

Catheter pump

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on August 1, 2023, with application number 202310957643.4 and invention name “Catheter Pump”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] Embodiments of the present disclosure generally relate to the field of medical devices, and more particularly to a catheter pump for pumping blood. Background Art

[0003] A catheter pump can be introduced into the patient's body through interventional means and assists in the transport of blood in the circulatory system. A catheter pump generally includes a pump head portion located within the patient's body and a motor portion located outside the patient's body. The motor portion can be connected to the pump head portion via a slender drive shaft arranged within the catheter to provide power to the pump head portion. As an example, when the pump head is deployed in the left ventricle, the catheter pump can pump blood from the left ventricle of the heart into the aorta; when the pump head is deployed in the right ventricle, the catheter pump can pump blood from the inferior vena cava into the pulmonary artery.

[0004] The pump head, catheter, and drive shaft are inserted into the patient's body at a predetermined location (e.g., the left ventricle). As these components are inserted into the heart along blood vessels, which are not straight, they must possess excellent flexibility and elasticity to ensure they can pass through the blood vessels.

[0005] Summary of the Invention

[0006] Embodiments of the present disclosure provide a catheter pump, aiming to improve one or more aspects of the performance of the catheter pump.

[0007] According to the first aspect of the present disclosure, a catheter pump is provided. The catheter pump includes: a catheter; a foldable pump head, including a pump housing and a membrane mounted on the pump housing, the pump housing accommodating an impeller therein and being mounted to the distal end of the catheter; a drive shaft rotatably disposed inside the catheter and connected to the impeller; wherein the catheter includes: a first section located inside the membrane; a second section located near the proximal end of the membrane and continuous with the first section toward the proximal end of the catheter; a third section continuous with the second section toward the proximal end of the catheter, the stiffness of the first section being less than the stiffness of the second section, and the stiffness of the second section being less than the stiffness of the third section. Thus, the arrangement of three sections with varying stiffness can improve the bending ability of the catheter during the interventional process, while effectively preventing accumulation caused by deformation of the membrane.

[0008] In some embodiments, the first section, the second section, and the third section may be made of the same material.

[0009] In some embodiments, the outer diameter of the first segment may be smaller than the outer diameter of the second segment, and the outer diameter of the second segment may be smaller than the outer diameter of the third segment.

[0010] In some embodiments, the second section may have a shape that gradually increases in size from the proximal end toward the distal end.

[0011] In some embodiments, the second section may be conical in shape.

[0012] In some embodiments, the average diameter of the proximal end of the second segment may differ from the average diameter of the distal end of the second segment by a range of 0.2 mm to 0.4 mm, particularly by a range of 0.25 mm to 0.35 mm.

[0013] In some embodiments, the size of the second section may be in the range of 5 mm to 20 mm, particularly in the range of 8 mm to 15 mm.

[0014] In some embodiments, the size of the third section may be in the range of 30 mm to 80 mm, particularly in the range of 50 mm to 60 mm. In some embodiments, the second section may be located outside the coating. In some embodiments, the second section may extend at least partially into the interior of the coating.

[0015] In some embodiments, the foldable pump head is capable of switching between an expanded configuration corresponding to a working state and a folded configuration corresponding to an interventional state, the catheter is pre-bent at the second section and the pump head is supported at least partially by the pre-bending stress formed by the pre-bending when the foldable pump head is in the expanded configuration. Thus, the pump head can be supported by the pre-bending stress provided by the pre-bending portion to improve the centering performance of the pump head during operation. In some embodiments, the catheter can be pre-bent at the second section at an angle such that, in the expanded configuration, the membrane and the impeller are supported by the second section in a manner substantially perpendicular to the organ tissue supporting the membrane. Thus, it is ensured that the pump head is supported centrally to keep away from the inner wall of the heart, preventing the inlet from adsorbing the inner wall of the heart or sucking the heart's chordae tendineae into the pump head and causing entanglement.

[0016] In some embodiments, the conduit may be pre-bent at the second section to an angle within a range of 120° to 150°, particularly within a range of 130° to 140°.

[0017] In some embodiments, the pre-bend can be formed during the process of integrally molding the catheter by injection molding. This ensures dimensional accuracy of the pre-bend. In some embodiments, in the folded configuration, the membrane and impeller can be configured to fold from the distal end of the catheter toward the proximal end of the catheter.

[0018] According to a second aspect of the present disclosure, a catheter pump is provided. The catheter pump comprises: a catheter; a drive shaft rotatably disposed within the catheter; a foldable pump head comprising a pump housing and a membrane mounted to the pump housing, the pump head being convertible between an expanded configuration corresponding to a working state and a folded configuration corresponding to an interventional state, wherein in the folded configuration, the membrane is configured to fold from the distal end of the catheter toward the proximal end of the catheter; wherein the catheter comprises: a distal portion extending from near the membrane to the distal end of the catheter; and a proximal portion continuous with the distal portion and extending from near the membrane toward the proximal end of the catheter, the distal portion having a stiffness less than that of the distal portion. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and other objects, features and advantages of the embodiments of the present disclosure will become readily understood by reading the following detailed description with reference to the accompanying drawings, in which several embodiments of the present disclosure are shown by way of example and not limitation.

[0020] FIG1 shows an overall schematic diagram of a catheter pump according to an embodiment of the present disclosure;

[0021] FIG2 is a schematic diagram showing a state where a catheter pump according to an embodiment of the present disclosure is deployed in the left ventricle;

[0022] FIG3 shows a partial schematic diagram of a catheter of a catheter pump according to one embodiment of the present disclosure;

[0023] FIG4 is a schematic diagram showing a state of a pump head portion of a catheter pump before being folded according to an embodiment of the present disclosure;

[0024] FIG5 is a schematic diagram showing a process in which a pump head portion of a catheter pump according to an embodiment of the present disclosure is folded.

[0025] In the various drawings, the same or corresponding reference numerals denote the same or corresponding parts. DETAILED DESCRIPTION

[0026] The preferred embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although preferred embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to make the present disclosure more thorough and complete, and to fully convey the scope of the present disclosure to those skilled in the art.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present invention pertains. The terms used herein in the specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0028] As used herein, the term "including" and its variations mean open inclusion, i.e., "including but not limited to." Unless otherwise stated, the term "or" means "and / or." The term "based on" means "based, at least in part, on." The terms "one example embodiment" and "an embodiment" mean "at least one example embodiment." The term "another embodiment" means "at least one additional embodiment."

[0029] The terms "near", "far", "front", "back", "inside" and "outside" used in the present disclosure are relative to the clinician who operates the catheter pump. The terms "near" and "back" refer to the parts that are relatively close to the clinician, and the terms "far" and "front" refer to the parts that are relatively far away from the clinician. For example, the extracorporeal part of the catheter is located at the proximal end and the front end, while the intracorporeal part of the catheter is located at the distal end and the back end. In addition, it should be understood that the directions "near", "far", "back", "front", "inside" and "outside" are defined for the convenience of description, and the catheter pump can be used in many directions and positions, so these terms expressing relative positional relationships are not restrictive and absolute. In the present disclosure, if the above definitions have other clear provisions and limitations, they should follow the above clear provisions and limitations. The following describes the catheter pump according to an embodiment of the present disclosure in conjunction with the accompanying drawings.

[0030] Figure 1 shows an overall schematic diagram of a catheter pump 1 according to an embodiment of the present disclosure. The catheter pump 1 typically needs to be at least partially inserted into a patient's body, for example, and can be deployed at a predetermined location in the left or right ventricle to pump blood, thereby at least partially replacing the heart's pumping function.

[0031] The catheter pump 100 includes a catheter 10, a motor 20, and a pump head 30. The motor 20 can be connected to the proximal end of the catheter 10 via a coupler and is configured as a power component to provide power. The distal end of the catheter 10 is connected to the pump head 30. A drive shaft 50 (see Figure 3) is provided inside the catheter 10, one end of which is connected to the power output end of the motor 20. The distal end of the catheter 10 is connected to the pump head 30.

[0032] The pump head 30 includes a pump housing and an impeller 34 mounted in the pump housing (see Figure 5), and the impeller 34 is connected to the other end of the drive shaft 50. Thus, when the drive shaft 50 rotates, the impeller is driven to rotate together. The pump housing includes a bracket in a metal lattice structure made of, for example, an alloy such as nickel or titanium. The metal lattice of the pump housing has a mesh design. The membrane 32 is mounted on the pump housing and, together with the pump housing, defines an inlet 31 for pumping blood in and an outlet 33 for pumping blood out. In some embodiments, the membrane 32 covers the middle and rear end portion of the pump housing (i.e., the proximal portion close to the pump housing), whereby the membrane 32 can form an outlet 33 for blood at the proximal end, and the front end (i.e., the distal end) of the pump housing that is not covered by the membrane 32 can form an inlet 31 for blood, for example, the inlet can be formed by the mesh of the pump housing. When the drive shaft 50 drives the impeller to rotate, as the impeller rotates, blood enters the fluid channel defined by the membrane 32 from the inlet 31 and flows out from the outlet 32 ​​through the membrane.

[0033] In some embodiments, the pump head 30 can be foldable. This has advantages in the context of catheter pump 1 interventional procedures. The pump head 30 and the front end of the catheter 10 of the catheter pump are inserted into and retained within the patient's body, so it is desirable to have the outer circumference of the pump head 30 and catheter 10 as small as possible. A smaller pump head 30 and catheter 10 means that the patient's body can be accessed through a smaller puncture port, reducing the pain caused to the patient during the interventional procedure and minimizing complications caused by an oversized puncture port. According to embodiments of the present disclosure, the pump head 30 can include a folded configuration and an unfolded configuration. In the folded configuration, the pump head 30 is folded, thereby occupying the smallest possible outer circumference. The folded configuration corresponds to the interventional procedure of the catheter pump 10. In the unfolded configuration, the pump head 30 returns from the folded configuration to the unfolded configuration. The unfolded configuration corresponds to the operating state of the catheter pump 10, in which the blood pumping channel of the pump head 30 is normally open and suitable for pumping blood.

[0034] In some embodiments, the pump housing of the pump head 30 can be made of an alloy material such as nickel-titanium. The pump head 30 can be implemented as a multi-mesh design, and at the same time, can be unfolded with the help of the memory properties of nickel-titanium alloy. The blades of the impeller are made of a flexible material or a shape memory material and can be folded relative to the hub. When the pump head 30 includes a folding configuration, the blades of the impeller are close to the hub to reduce the size occupied. After the external force constraining the blades of the impeller is released, the stored energy of the blades is released, causing the blades to unfold and return to the unfolded state.

[0035] The catheter pump 1 also includes a protective head 40 connected to the distal end of the pump head 30. When the catheter pump 1 is inserted into a predetermined position in the human body, the protective head 40 can guide the insertion of the catheter pump. After the catheter pump 1 is inserted into the predetermined position in the human body (i.e., after the catheter pump is deployed in place), during the operation of the catheter pump 1, the protective head 40 can maintain the posture of the pump head in the heart, preventing the pump head from adsorbing the inner wall of the heart or sucking the heart's chordae tendineae into the pump head, thereby causing danger. The protective head 40 is configured to be soft so as not to harm the patient's tissue. In some embodiments, the flexible end of the protective head 40 is supported on the inner wall of the ventricle in a non-invasive or non-destructive manner, separating the inlet 31 of the pump head 30 from the inner wall of the ventricle. In the illustrated embodiment, the protective head 40 is in a straight line shape. It should be understood that the illustrated shape is merely exemplary, and the protective head 40 can be in any other appropriate shape.

[0036] Figure 2 shows a schematic diagram of a catheter pump 1 deployed in the left ventricle according to an embodiment of the present disclosure. It should be understood that the illustrated embodiment is merely exemplary, and the catheter pump can also be placed in other target locations of a patient as desired, such as the right ventricle, blood vessels, or other organs, through invasive surgery.

[0037] Considering that the path from the outside of the body to the intended insertion point inside the human body is not a straight line, the catheter 10 of the catheter pump 1 is typically made of a flexible material to ensure sufficient contour-following capability. The inventors of this application have discovered through extensive testing that, while the catheter 10 maintains a constant stiffness throughout its length, particularly over a considerable length from the pump head to the proximal end of the catheter, the vascular navigation capability of the catheter 10 is unsatisfactory. Specifically, the catheter 10's ability to negotiate corners is unsatisfactory.

[0038] According to the requirements of the deployment position of the catheter pump 1, it is expected that the catheter 10 has a certain degree of rigidity. When the catheter pump 1 is in the working state shown in Figure 2, the pump head 30 of the catheter pump 1 is centered as much as possible relative to the supporting pump head tissue of the heart. One of the purposes of centering is to keep the pump head away from the inner wall of the heart to prevent the inlet from adsorbing the inner wall of the heart or sucking the heart's tendons into the pump head and causing entanglement. However, when the catheter pump 1 is in operation, considering the pumping action of the blood fluid, a large reaction force will be generated on the pump head 30, causing the posture of the pump head 30 to deflect. When the catheter 10 has sufficient rigidity, the posture of the pump head can be maintained as much as possible through the synergistic effect of the rigidity of the catheter and the protective head 40.

[0039] On the other hand, it is desirable that the catheter 10 be as flexible as possible to provide better contour-following capabilities. In the embodiment shown in FIG2 , when the catheter 10 is deployed along the contour of the vessel wall through interventional means to the position shown in FIG2 , the catheter 10 needs to pass through regions of significant vessel curvature, such as the aortic arch region shown in FIG2 . In these regions of significant curvature, there is a significant risk that the catheter 10 will contact the inner wall of the aortic arch, preventing further advancement. In such situations, it is desirable that the catheter 10 have sufficiently low stiffness to provide good cornering capabilities.

[0040] In response to the above-mentioned problems, according to an embodiment of the present disclosure, a catheter 10 with variable stiffness is provided. In particular, the catheter 10 has a large stiffness in the portion near the proximal end; while the stiffness of the portion near the distal end is smaller than that of the portion near the proximal end. The term "portion near the proximal end" here can be understood as relative to the area where the membrane of the pump head 30 is located, that is, the portion near the proximal end relative to the area where the membrane of the pump head 30 is located. In some embodiments, as shown in Figure 2, the "portion near the proximal end" may correspond to the area indicated by reference numeral 16 (i.e., the third segment). The area indicated by reference numeral 16 may correspond to the area with the largest curvature during deployment to the heart (i.e., the area that requires the catheter 10 to have the greatest ability to make bends). In the deployment scenario shown in Figure 2, it may correspond to the area extending from the aortic arch to the vicinity of the pump head. The stiffness of the portion of the catheter 10 from segment 16 to the coupling portion of the motor 20 may be the same as the stiffness of segment 16, or greater than the stiffness of segment 16. Similarly, the “portion near the distal end” can be understood as the portion near the distal end relative to the area where the membrane of the pump head 30 is located. In some embodiments, as shown in FIG2 , the “portion near the distal end” can correspond to the areas indicated by reference numerals 12 and 14 .

[0041] According to the present disclosure, since the "proximal portion" occupies a considerable area of ​​the catheter 10, sufficient basic rigidity of the catheter can be provided by this "proximal portion." Furthermore, this basic rigidity of this area can provide sufficient rigidity support for the pump head 30 relative to the area adjacent to the pump head, which has the benefit of ensuring that the pump head is "centered" during operation of the catheter pump. On the other hand, the "distal portion," corresponding to the area where the pump head is located and / or the area near the area where the pump head is located, only occupies a portion of the distal end of the catheter 10. The reduced rigidity of this "distal portion" can provide good bending ability for the front portion of the catheter. This ensures that the catheter 10 can be guided to the deployment position of the catheter pump 1 without difficulty.

[0042] In some embodiments, the difference in rigidity can be provided by the selection of different materials. That is, the portion near the distal end of the conduit and the portion near the proximal end of the conduit can be made of materials with different rigidity, providing rigidity by the difference in material. Additionally or alternatively, the portion near the distal end of the conduit and the portion near the proximal end of the conduit can be made of the same material, and different rigidity can be provided by forming the portion near the distal end of the conduit and the portion near the proximal end of the conduit into different sizes. As an example, the outer diameter of the portion near the distal end of the conduit is greater than the outer diameter of the portion near the proximal end of the conduit.

[0043] In some embodiments, the "portion near the distal end" can be further divided into multiple regions of varying stiffness to further enhance catheter pump performance. In some embodiments, as shown in FIG2 , the "portion near the distal end," indicated by reference numerals 12 and 14 , can include a first segment 12 and a second segment 14 located near the proximal end of the coating 32 and continuous with the first segment 12. The first segment 12 is located within the coating 32 and corresponds to the distal end of the catheter. The second segment 14 is located near the proximal end of the coating 32 and continuous with the first segment 12. The second segment 14 corresponds to the transition region between the third segment 16 and the first segment 12. The first segment 12 and the second segment 14 can have different stiffnesses. Specifically, the first segment 12 can have a lower stiffness than the second segment 14, and the second segment 14 can have a lower stiffness than the third segment 16. This arrangement of multiple regions of varying stiffness can compensate for issues associated with the folding of the foldable pump head 30 and provide other additional technical benefits, which will be discussed in detail later.

[0044] In some embodiments, different stiffness can be achieved by selecting different materials. That is, the first segment 12, the second segment 14, and the third segment 16 can be made of different materials to provide stiffness. In other embodiments, the first segment 12, the second segment 14, and the third segment 16 can be made of the same material and can be formed into different sizes to provide different stiffness. For example, the outer diameter of the first segment 12 can be smaller than the outer diameter of the second segment 14, and the outer diameter of the second segment 14 can be smaller than the outer diameter of the third segment 16.

[0045] In some embodiments, the second section 14 has a shape that gradually increases in size from the proximal end to the distal end. In some embodiments, as shown in FIG3 , the second section 14 has a conical (including a frustum) shape. This gradual shape helps eliminate or mitigate deformation accumulation of the coating. In some embodiments, the average diameter of the proximal end of the second section 14 differs from the average diameter of the distal end of the second section 14 by 0.2 mm to 0.4 mm, particularly by 0.25 mm to 0.35 mm. Extensive testing has found that this numerical range is effective in improving the catheter's bending ability and coating deformation accumulation. It should be understood that the illustrated shapes are merely exemplary, and the first section 12, second section 14, and third section 16 can be formed into any suitable shape as long as the above stiffness requirements are met. In some embodiments, the second section 14 is located near the proximal end of the coating 32. The difference in stiffness between the second section 14 and the first section 12 helps compensate for or mitigate deformation accumulation of the coating when the pump head 30 is folded.

[0046] In some embodiments, the third section 16 corresponds to an area where the catheter has high bending requirements. In the deployment scenario shown in Figure 2, it may correspond to the area extending from the aortic arch to the vicinity of the pump head. In some embodiments, the size of the third section 16 is in the range of 30mm-80mm, in particular in the range of 50mm-60mm. After testing the above-mentioned size range, it was found that the above-mentioned size range can meet the rigidity requirements. It should be understood that the size range of the third section is merely exemplary, and the third section can be set to other appropriate size ranges based on the application scenario of the catheter pump and the differences between individuals. The so-called size in this article refers to the length of the section.

[0047] When the pump head 30 of the catheter pump is inserted along the blood vessel to the position to be deployed, the impeller and housing of the pump head 30 are in a folded state (for example, the impeller and housing are folded from the distal end to the proximal end, see Figures 4 and 5, which will be described later), and the membrane 32 is also folded together; however, since the membrane 32 itself is flexible, when the pump head 30 is advanced along the blood vessel, the membrane 32 will deform due to, for example, the action of blood and / or the propulsion force, and these deformations are undesirable. On the one hand, these deformations not only increase the resistance to the advancement of the pump head 30; but also, when the deformation is severe, the accumulation of deformation may affect the performance of the pump head 30. By providing the second section 14 with increased stiffness relative to the first section 12, the above-mentioned deformation accumulation of the membrane can be alleviated or eliminated; and by providing the second section 14 with reduced stiffness relative to the third section 16, the bending ability of the catheter can be improved.

[0048] In some embodiments, the second segment 14 can be located outside and adjacent to the proximal end of the coating 32. In some embodiments, the second segment 14 extends at least partially into the interior of the coating 32. In some embodiments, the size of the second segment 14 is in the range of 5 mm to 20 mm, particularly in the range of 8 mm to 15 mm. Extensive testing has found that this range of values ​​is effective in improving the catheter's bending ability and coating deformation accumulation.

[0049] In some embodiments, the catheter 10 is further provided with auxiliary measures at the second section 14 to further enhance the performance of the second section 14. In some embodiments, the catheter 10 is pre-bent at the second section 14. The term "pre-bending" herein refers to a molding process that, when an external force is applied to the catheter 10 to straighten the catheter (e.g., during insertion of the catheter 10 into the human body), the catheter 10 will be straightened at the second section 14 under the action of the external force. After the external force constraining the catheter 10 is removed (e.g., after the pump head of the catheter pump 1 is deployed to the intended deployment location), the catheter 10 will maintain the pre-bent shape at the second section 14.

[0050] By pre-bending the second section 14, the membrane 32 can be supported at least partially by the pre-bending stress formed by the pre-bending when the foldable pump head 30 is in the expanded configuration. In this case, the posture of the pump head 30 relative to the organ tissue 70 can be ensured. In the expanded configuration, the membrane 32 and the impeller 34 are supported by the second section 14 in a manner substantially perpendicular to the vascular tissue used to support the membrane 32. In this way, the pump head can be kept away from the inner wall of the heart, preventing the inlet from adsorbing the inner wall of the heart or sucking the heart's tendons into the pump head and causing entanglement. In some embodiments, the catheter 10 is pre-bent at the second section 14 to an angle in the range of 120° to 150°, in particular, an angle in the range of 130° to 140°. According to a large number of clinical tests, when the pump head is in the working position, the final angle of the above-mentioned bend enables the pump head to be centered.

[0051] Pre-bending can be achieved in a variety of ways. In some embodiments, the catheter 10 is integrally formed by injection molding, and the pre-bend is formed during the process of integrally forming the catheter 10 by injection molding. In some embodiments, after the catheter is integrally formed, the catheter 10 can be heat-treated and bent into a predetermined shape by heat treatment. For example, the catheter 10 can be annealed to form a curved structure; other heat treatments for forming pre-bends can also be considered, for example, the catheter 10 can be heated on a core shaft used for molding to form a pre-bend on the catheter 10. Considering the size requirements of multiple sections, forming a pre-bend in the process of integrally forming the catheter 10 by injection molding has advantages in ensuring dimensional accuracy.

[0052] After the catheter 10 forms a pre-bend at a predetermined position, a straightening force may be applied to the catheter 10 to straighten the pre-bend portion of the catheter, and after the straightening force is removed, the catheter 10 returns to its pre-formed bent state in a relaxed state.

[0053] As previously mentioned, the pump head 30 of the catheter pump 1 according to an embodiment of the present disclosure is a foldable pump head. Before the catheter pump 1 is inserted into the human body, it needs to be folded to reduce the volume occupied by the pump head. Figures 4 and 5 respectively show the pump head of the catheter pump 1 according to an embodiment of the present disclosure before and after being folded.

[0054] Figure 4 illustrates a schematic diagram of the pump head 30 of the catheter pump 1 before folding, according to an embodiment of the present disclosure. As shown in Figure 4 , a separate introducer 60 may be provided. The introducer 60 may include a reduced-size, funnel-shaped base 62 and an access tube 64. The base 62 is shaped to apply force to the pump head 30, compressing it from an expanded state to a folded state. Figure 5 illustrates a schematic diagram of the pump head 30 during folding, according to an embodiment of the present disclosure. As shown in Figure 5 , the pump head 30 of the catheter pump 1 is initially inserted into the introducer 60. After the protective portion 40 of the catheter pump 1 passes through the base 62 and into the access tube 64, the pump head 30 begins to enter the base 62. The cavity wall of the base 62 contacts the pump head 30, exerting a compressive force on the pump head 30. Under the action of this compressive force, the pump head 30 folds from the distal end of the catheter 10 toward the proximal end. Specifically, the pump housing and impeller 34 of the pump head 30 fold from the distal end of the catheter 10 toward the proximal end, forming a compact configuration.

[0055] The folded pump head 30 then enters the interventional tube 64 and maintains a compact configuration under the compression of the wall of the interventional tube 64. Then, the catheter pump 1 can continue to be advanced to gradually advance the pump head portion of the catheter pump 1 and the catheter 10 to the deployment position of the catheter pump 1 to be deployed. During the intervention process, considering that the coating 32 of the pump head 30 is made of a flexible material, in the process of continuing to advance the pump head portion of the catheter pump 1 and the catheter 10, material accumulation will occur at the distal end of the pump head of the coating, and this material accumulation is undesirable. According to an embodiment of the present disclosure, the catheter 10 forms sections 12 and 14 with different stiffness in the area near the coating 32, and in particular, the second section 14 has a stiffness greater than that of the first section. By increasing the stiffness, the coating material accumulation can be effectively reduced or alleviated while ensuring the good bending ability of the catheter 10.

[0056] In addition, although adopting specific order to describe each operation, this should be understood as requiring such operation to be carried out in the specific order shown or in sequential order, or requiring that all illustrated operations should be carried out to obtain desired results. Under certain circumstances, multitasking and parallel processing may be advantageous. Similarly, although comprising some specific implementation details in the above discussion, these should not be interpreted as limiting the scope of the present disclosure. Some features described in the context of separate embodiment can also be implemented in a single implementation in combination. On the contrary, the various features described in the context of a single implementation also can be implemented in a plurality of implementations individually or in the mode of any suitable subcombination.

[0057] Although the subject matter has been described in language specific to structural features and / or methodological logical acts, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are merely example forms of implementing the claims.

[0058] While various embodiments of the present disclosure have been described above, the foregoing description is intended to be illustrative, non-exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is selected to best explain the principles of the embodiments, their practical applications, or technological improvements in the marketplace, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A catheter pump, comprising: A catheter (10); A foldable pump head (30) comprising a pump housing and a membrane (32) mounted on the pump housing, wherein the pump housing accommodates an impeller (34) inside the pump housing and is mounted to the distal end of the conduit (10); a drive shaft (50) rotatably disposed inside the conduit (10) and connected to the impeller (34); The catheter (10) comprises: a first section (12) located inside the coating (32); A second section (14) located near the proximal end of the coating (32) and continuous with the first section (12) toward the proximal end of the catheter (10); and a third section (16) continuous with the second section (14) toward the proximal end of the catheter (10), wherein the stiffness of the first section (12) is smaller than the stiffness of the second section (14), and the stiffness of the second section (14) is smaller than the stiffness of the third section (16).

2. The catheter pump according to claim 1, wherein the first section (12), the second section (14) and the third section (16) are made of the same material.

3. The catheter pump according to claim 2, wherein the outer diameter of the first section (12) is smaller than the outer diameter of the second section (14), and the outer diameter of the second section (14) is smaller than the outer diameter of the third section (16). 4 . The catheter pump according to claim 3 , wherein the second section ( 14 ) has a shape with a size gradually increasing from the proximal end toward the distal end.

5. The catheter pump according to claim 4, wherein the second section (14) is conical in shape.

6. The catheter pump according to claim 4, wherein an average diameter of the proximal end of the second section (14) differs from an average diameter of the distal end of the second section (14) in the range of 0.2 mm to 0.4 mm, in particular in the range of 0.25 mm to 0.35 mm.

7. The catheter pump according to claim 1, wherein a size of the second section (14) is in the range of 5 mm to 20 mm, in particular in the range of 8 mm to 15 mm.

8. The catheter pump according to any one of claims 1 to 7, wherein the size of the third section (16) is in the range of 30 mm to 80 mm, in particular in the range of 50 mm to 60 mm.

9. The catheter pump according to any one of claims 1 to 7, wherein the second section (14) is located outside the membrane (32).

10. The catheter pump according to any one of claims 1 to 7, wherein the second section (14) at least partially extends to the interior of the membrane (32).

11. A catheter pump according to any one of claims 1-7, wherein the foldable pump head (30) is capable of switching between an expanded configuration corresponding to a working state and a folded configuration corresponding to an interventional state, the catheter (10) is pre-bent at the second section (14) and the pump head (30) is supported at least partially by a pre-bending stress formed by the pre-bending when the foldable pump head (30) is in the expanded configuration.

12. A catheter pump according to claim 11, wherein the angle at which the catheter (10) is pre-bent at the second section (14) is configured such that, in the expanded configuration, the membrane (32) and the impeller (34) are supported by the second section (14) in a manner substantially perpendicular to the organ tissue supporting the membrane (32).

13. The catheter pump according to claim 11, wherein the catheter (10) is pre-bent at the second section (14) to an angle in the range of 120° to 150°, in particular in the range of 130° to 140°.

14. The catheter pump according to claim 11, wherein the pre-bend is formed during the process of integrally molding the catheter (10) by injection molding.

15. The catheter pump of claim 11, wherein in the folded configuration, the membrane (32) and the impeller (34) are configured to be folded from a distal end of the catheter (10) toward a proximal end of the catheter (10).

16. A catheter pump comprising: A catheter (10); A drive shaft (50) rotatably disposed inside the catheter (10); A foldable pump head (30), comprising a pump housing and a covering membrane (32) mounted to the pump housing, wherein the pump head (30) is convertible between an unfolded configuration corresponding to a working state and a folded configuration corresponding to an interventional state, and in the folded configuration, the covering membrane (32) is configured to be folded from the distal end of the catheter (10) toward the proximal end of the catheter (10); Wherein, the catheter (10) comprises: a portion extending from the vicinity of the coating (32) to the A portion close to the distal end of the distal end of the catheter; and a portion close to the proximal end that is continuous with the portion close to the distal end and extends from near the coating (32) toward the proximal end of the catheter (10), wherein the stiffness of the portion close to the distal end is less than the stiffness of the portion close to the distal end.

Images