Outlet tube and outlet tube assembly

Abstract

An integrated outflow tube balloon, either alone or as part of another device, and a method of manufacturing the device may be provided. The balloon may include a flexible tubular polymer layer having a distal end and a proximal end and an outer surface and an inner surface. The balloon may include one or more openings at the proximal end, the one or more openings extending from the outer surface to the inner surface. The balloon may include a slot extending from its proximal end to the proximal end of one of the one or more openings. The balloon may include a distal end configured to be disposed over an expandable housing.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Patent Application No. 63 / 438,881, filed January 13, 2023, the entire contents of which are incorporated herein by reference.

[0002] Technical Field The present disclosure is directed to an outflow tube for a catheter-based heart pump. [Background technology]

[0003] background In catheter-based heart pumps, outflow tubing may be used to control the flow of blood after it leaves the pump housing. However, the design of such outflow tubing means that the manufacturing process for producing and attaching such outflow tubing to the heart pump is complex. Such complexity can lead to defects. Summary of the Invention [Means for solving the problem]

[0004] overview The present system and techniques improve upon the prior art in several ways.

[0005] In some embodiments, an integrated outflow tube balloon may be provided. The integrated outflow tube balloon may include one or more openings at the proximal end of the balloon. The balloon may include a slot extending from the proximal end of the balloon to the proximal end of one of the one or more openings. The balloon may include a central portion configured to be operably coupled to the expandable housing. The balloon may include a distal portion configured as an inflow mesh.

[0006] In some embodiments, an outflow tube assembly may be provided, which may include an expandable housing and / or an integral outflow tube balloon as disclosed herein operably coupled to an inner coating of the housing. The housing may include a filter portion at the inflow portion.

[0007] In some embodiments, a medical device may be provided that may include an integral outflow tube balloon as disclosed herein operably coupled to a catheter at a proximal end and operably coupled to an expandable housing and / or an inner coating of the housing.

[0008] In some embodiments, a method for manufacturing a device may include creating a first subassembly by providing an inner coating on a mandrel, creating a second subassembly by providing an expandable housing over the inner coating, creating a third subassembly by placing an integral outflow tube balloon over the housing and inner coating, bonding the inner coating and housing to a portion of the integral outflow tube balloon (e.g., by heat welding), and optionally removing a portion of the integral outflow tube balloon to form an inflow mesh.

[0009] BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the general description of the invention given above and the detailed description of the embodiments given below, serve to explain the principles of the invention. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 10 is a diagram of the outflow tube assembly. [Figure 2] FIG. 1 is a diagram of the inner coating. [Figure 3] FIG. [Figure 4]FIG. 1 is a diagram of an outflow tube balloon. [Figure 5] 5 is a cross-sectional view of the inflow region of the expandable housing of FIG. 4 with an expandable filter mounted thereon, also showing the inner coating. [Figure 6] FIG. 10 is a side view of the housing, outflow tube, and expandable filter. [Figure 7] FIG. 7 is a perspective view of the inlet region of the expandable housing of FIG. 6. [Figure 8] 1 is a flow chart of a manufacturing process for an outflow tube. [Figure 9A] FIG. 1 is a front view of one embodiment of an outflow tubing balloon. [Figure 9B] FIG. 10 is a rear view of one embodiment of an outflow tube balloon. [Figure 9C] FIG. 10 is a top view of one embodiment of an outflow tube balloon. [Figure 9D] FIG. 10 is a bottom view of one embodiment of an outflow tube balloon. [Figure 9E] FIG. 10 is a right side view of one embodiment of an outflow tube balloon. [Figure 9F] FIG. 10 is a left side view of one embodiment of an outflow tube. DETAILED DESCRIPTION OF THE INVENTION

[0011] It should be understood that the accompanying drawings are not necessarily to scale, and present somewhat simplified representations of various features illustrating the underlying principles of the present invention. Specific design features of the sequences of operations as disclosed herein, including, for example, the specific dimensions, orientations, locations, and shapes of the various illustrated components, are determined in part by the particular intended application and use environment. Certain features of the illustrated embodiments have been enlarged or distorted relative to others to facilitate visualization and clear understanding. In particular, thin features may be thickened, for example, for clarity or illustration purposes.

[0012] Detailed Description The following description and drawings merely illustrate the principles of the present invention. Accordingly, it will be understood by those skilled in the art that various arrangements, not explicitly described or shown herein, can be devised that embody the principles of the present invention and are within its scope. Furthermore, all examples recited herein are expressly intended to be merely illustrative, primarily to aid the reader in understanding the principles of the present invention and the concepts provided by the inventors to further the art, and should be construed as not being limited to such specifically recited examples and conditions. Furthermore, as used herein, the term "or" refers to a non-exclusive or (e.g., "or otherwise" or "or alternatively") unless otherwise indicated. Furthermore, the various embodiments described herein are not necessarily mutually exclusive, as some embodiments can be combined with one or more other embodiments to form new embodiments.

[0013] Many of the innovative teachings of the present application will be described with particular reference to presently preferred exemplary embodiments. However, it should be understood that this type of embodiment provides only a few examples of the many advantageous uses of the innovative teachings herein. In general, statements made in the specification of the present application do not necessarily limit any of the various claimed inventions. Moreover, some statements may apply to some inventive features but not to others. Those skilled in the art and informed by the teachings herein will recognize that the present invention is applicable to a variety of other technical fields or embodiments.

[0014] An improved effluent tube may be provided, thereby avoiding various elements or manufacturing steps. For example, in various embodiments, two heat welding transformations may be avoided, an outer coating may no longer be required, processing aids (e.g., various mandrels or other tools used during manufacturing) are no longer needed, and excess effluent tube does not need to be trimmed during or after manufacturing.

[0015] Referring to Figure 1, an outflow tube assembly is shown. The outflow tube assembly 1 can include an inner coating 10. The inner coating may be disposed on the inner surface of an expandable housing 20. Note that in Figure 1, the expandable housing around the inner coating is not shown for ease of understanding. Figure 3 shows an example of a typical expandable housing.

[0016] Because these devices are configured to be placed, for example, in a patient's blood vessel, the housing may have an inlet portion 23 configured to allow blood to enter the housing and an outlet portion 25 configured to allow blood to exit the housing, and may have a central portion 24 extending between the proximal end of the inlet portion and the distal end of the outflow portion. The housing may have a proximal portion 26 extending proximally from the proximal end of the outflow portion. The proximal portion may be configured to couple to a catheter (not shown). The housing may have a distal portion 29 extending distally from the distal end of the inflow portion.

[0017] Simplified embodiments of these two elements (inner coating and expandable housing) are shown in FIGS.

[0018] Inner coating 10 is shown in FIG. 2 as being generally cylindrical about central axis 99 and has an axial length 11, an inner diameter 12, and a thickness 13. In some embodiments, the axial length may be equal to the axial length of central portion 24 of the housing. That is, in some embodiments, axial length 11 may be equal to the axial distance 28 between the proximal end of the inflow section and the distal end of the outflow section (see FIG. 4A). In some embodiments, the axial length may be shorter than the axial length of the central portion. The inner diameter is generally smooth to reduce any effect on blood flow through the central portion.

[0019] One embodiment of an expandable housing 20 is shown in FIG. 3. The housing 20 may have a distal end 21 and a proximal end 22. The housing may be formed at least in part from a plurality of struts 27, the struts configured to form an inflow section 23, an outflow section 25, and a central section extending between the proximal end of the inflow section and the distal end of the outflow section. The central section may have an axial length 28. The housing may include a proximal section 26 formed from the struts proximal to the outflow section. The housing may include a distal section 29 formed from the struts distal to the inflow section.

[0020] The housing can be radially expandable. The inlet, central, and outlet sections of the housing can be configured to have a compressed state and an expanded state. The housing can be configured to be disposed around a catheter (not shown).

[0021] If the housing is expandable, it may include a plurality of struts, represented by struts made of a suitable shape memory or hyperelastic material, such as nitinol. Hyperelastic materials are typically elastomers. Many such elastomers can elastically deform up to about 100%. Some superelastic materials can elastically deform up to about 6-8%. Nitinol is a trade name for a nickel-titanium alloy, distinguished from other materials by its shape memory and superelastic properties.

[0022] The struts may be made from wire or other filaments. The housing is generally configured to provide a "cage" around the impeller positioned within the housing (see impeller 200 in FIG. 5). The length of the housing may be shorter when radially expanded than when the housing is radially compressed. The change in length may be due to the struts unwinding as the housing expands. In some embodiments, the change in length when going from a compressed to an expanded state may be about 1-2 mm.

[0023] In some embodiments, the proximal portion may include a connector 50, which may be a rigid connector coupled to one or more struts. The connector may define a lumen (not shown) extending from the proximal end to the distal end of the connector. The connector may be configured with one or more openings 51 extending from the outer surface to the inner surface of the connector. The connector may be configured to couple to a catheter (not shown).

[0024] The outflow tube assembly 1 may include an attached outflow tube balloon 30, where at least a portion 31 is configured to be operably attached to the housing and / or inner coating. The outflow tube balloon may be flexible. In some embodiments, the outflow tube balloon may comprise a polymer such as PET or PU. The thickness of the outflow tube balloon may be, for example, from about 10 μm to about 100 μm thick. The thickness of the outflow tube balloon may vary axially. The outflow tube balloon may be formed, for example, using a blow molding manufacturing process.

[0025] The outflow tube balloon may include one or more openings 35 extending from the outer surface 36 to the inner surface 37 of the outflow tube balloon. In some embodiments, one or more of the openings may have the same shape. In some embodiments, one or more of the openings may have different shapes. The outflow tube may be configured to be coupled to a catheter (not shown) at a proximal end 32 positioned similarly to the location of the mandrel.

[0026] The outflow tube balloon is configured to be positioned around and proximal to the outflow port from the housing such that blood exiting the outflow port enters a volume defined by the inner surface of the outflow tube balloon and flows generally axially toward the one or more openings where it then exits the outflow tube and is returned to the blood vessel.

[0027] To aid in assembly and manufacturing, the outflow tube may include a slot 40 or slit that extends through a portion of the outflow tube balloon from the proximal end to one of the one or more openings 35. In some embodiments, the slot may include a straight portion 41 that extends axially from the proximal end toward the triangular portion 38 of the one or more openings 35, where the apex of the triangular portion meets the slit.

[0028] The one or more openings may include multiple openings. In some embodiments, each opening is the same circumferential distance from an adjacent opening. In some embodiments, at least a first opening is a different circumferential distance from an adjacent opening compared to a second opening (e.g., the openings may not be equally spaced around the circumference of the outflow tubing balloon). In some embodiments, there may be between 3 and 8 openings. In some embodiments, there may be between 3 and 4 openings. In some embodiments, there may be 4 openings.

[0029] 5, the use of the disclosed outflow tube can be shown in conjunction with a medical device. The medical device can be, for example, a blood pump, such as a catheter-based blood pump.

[0030] An impeller 200 is shown located within the housing 20 and mechanically coupled to a proximally located motor (not shown) via a flexible drive shaft 202 .

[0031] The inner central portion of the housing 20 may have an inner coating 10 that defines a channel through which blood is pumped by the impeller 200. Proximal and distal to this channel, the housing 20 allows blood to be drawn into the housing through the inlet portion 23 and pushed out of the housing through the outlet portion 25 to a downstream portion of the outflow tubing balloon 30. The housing may include a proximal tapered housing portion 502 adjacent to the intermediate housing portion 24.

[0032] In some embodiments, the housing may include an inflow mesh or filter portion. In some embodiments, the housing may include a portion disposed outside the housing to form the expandable filter 530. In some embodiments, the filter 530 may include a distal tubular filter section 514 having a relatively small diameter and a proximal tubular filter section 516 as a larger diameter (in its expanded state). The exact cross-sectional shape of the filter 530, including the exact cross-sectional shapes of the distal tubular filter section 514 and the proximal tubular filter section 516, may depend on the number of struts in the housing and / or the filter. Generally, the cross-sectional shape may be a polygon, possibly with rounded corners. The distal tubular filter section 514 may be disposed over the distal bearing 512.

[0033] In some embodiments, the distal end of the outflow tubular balloon may be heat sealed, such as by welding, through one or more holes defined by the struts of the distal tubular filter section 514 that extend to the proximal section of the flexible atraumatic tip 599.

[0034] As seen in FIG. 6 , in some embodiments, expandable filter 530 may include a transition zone 724 where distal tubular filter section 514 and tapered filter section 518 meet. The holes, exemplified by holes 726 in transition zone 724, are longer and wider than adjacent holes in tapered filter section 518. Preferably, holes 726 in transition zone 724 are at least twice as large as adjacent holes, exemplified by holes 728 in tapered filter section 518. In one embodiment, for each pair of circumferentially adjacent holes 728 in a row in tapered filter section 518, transition zone 724 has one hole 726 that circumferentially straddles the two holes 728. Thus, the number of holes in a circumferential row in transition zone 724 is half the number of holes in a circumferential row in tapered filter section 518. In some other embodiments, other ratios, such as 3:1, 4:1, or 3:2, may be used. Each hole 726 in transition zone 724 may be approximately two, three, or another multiple of the length (in the longitudinal direction) and two, three, or another multiple of the width (in the circumferential direction) of holes 728 in tapered filter section 518, depending on the ratio of the number of holes 728 in a row in tapered filter section 518 to the number of holes 726 in a row in transition zone 724.

[0035] The size and shape of holes 702-706 and 728, and the dimensions of struts 714-716 should be selected so that when tapered filter section 518 is fully open, the inlet of the housing in its expanded state can be positioned within tapered filter section 518 without exceeding the limits of elastic deformation of the material. For example, the length of two circumferentially adjacent struts 714-716 (on a zigzag of a zigzag circumferential ring) multiplied by the number of apertures 702-706 in the circumferential row should approximately equal the circumference of the fully expanded housing, taking into account any local elastic deformation of the filter material.

[0036] Apertures 702-706 are positioned such that the material between apertures 702-706, exemplified by materials 708, 710, and 712, forms first and second struts. Two exemplary struts 714 and 716 are shown in Figure 6 by thick dashed lines. As noted above, the generally spiral curves may include small zigzags, as exemplified by generally spiral curves 714 and 716, but they are not necessarily all the same. These zigzags are more clearly shown in the inset of Figure 6, for example, in struts 718 and 720 (which are shown by thick solid and dashed lines).

[0037] Adjacent holes 726 in the transition zone 724 are separated from one another by struts that are wider than adjacent struts 714-716 in the tapered filter section 518. These wider struts stabilize the larger holes 726. When the distal portion 520 of the outflow tubing balloon is positioned longitudinally proximally across the distal tubular filter section 514 to the transition zone 724, the distal portion 520 at least partially covers the first one or more rows of holes 726 in the transition zone 724, thus reducing their effective size. In some cases, the size of these reduced holes can lead to an increased risk of blood damage or clotting. Therefore, the holes 726 in the transition zone 724 should be selected to be larger than the holes in the tapered filter section 518.

[0038] As shown in FIGS. 6 and 7 , the holes 728 in the distal region of tapered filter section 518 are narrower circumferentially than the holes 702-706 in the proximal region of tapered filter section 518. In other words, the size of apertures 702-706 increases monotonically proximally along the longitudinal axis. Additionally, in distal tubular filter section 514, holes 722 take the form of narrow axial slits that are circumferentially offset from one another. This is advantageous because the narrow holes can widen when expandable filter 530 is expanded in the distal region of tapered filter section 518 and in distal tubular filter section 514, such as when impeller 200 is inserted into the housing. The wider holes are bounded by thicker struts, particularly in tapered filter section 518. The struts have widths of approximately 30 μm in the distal region of tapered filter section 518 and approximately 60 μm in the proximal region. Preferably, the maximum diameter of the pores in tapered filter section 518 is between about 300 μm and about 500 μm.

[0039] 6 and 7, the proximal tubular filter portion 516 does not have any holes. However, holes may be desired in the proximal tubular filter portion 516, such as when an integral outflow tubular balloon 30 is disposed over the proximal tubular filter section 516 (see FIG. 5), which is also located over the central / intermediate housing portion 24.

[0040] As such, in some embodiments, the portion of the outflow tube disposed around the inflow portion may include a plurality of apertures that align with apertures in the inflow portion 23 and / or filter 530 .

[0041] A method for manufacturing such a device is shown with reference to Figure 8. The method 100 may include a first step of assembling 110 an inner coating on a mandrel to form a first subassembly.

[0042] The method may include a second step of assembling 120 a housing onto the first subassembly to form a second subassembly.

[0043] The method may include inserting 130 an outflow tube balloon, where the distal end of the mandrel is threaded through the proximal end of the outflow tube balloon, and then bringing the outflow tube balloon proximally over the second subassembly until the outflow tube balloon is correctly positioned, forming a third subassembly.

[0044] The method may include the step of bonding the outflow tube balloon to the housing and / or inner coating and / or the step of ablating the outflow tube balloon 140. Specifically, the outflow tube balloon may be bonded to the housing and / or inner coating via a suitable method, such as thermal bonding. The outflow tube balloon may be ablated, for example, by laser ablation, to cut the design of at least a portion of the outflow tube balloon. This step forms an outflow assembly.

[0045] The method may include removing 150 the mandrel from the outflow assembly.

[0046] In some embodiments, various views of one embodiment of an outflow tubing balloon prior to any laser ablation are shown in Figures 9A-9F.

[0047] Various modifications may be made to the systems, methods, devices, mechanisms, techniques, and portions thereof described herein with respect to the various figures, and such modifications are contemplated as being within the scope of the present invention. For example, a particular order of steps or arrangements of functional elements may be presented in various embodiments described herein, and various other orders / arrangements of steps or functional elements may be utilized in connection with various embodiments. Furthermore, while modifications to embodiments may be discussed individually, various embodiments may employ multiple modifications simultaneously or sequentially, combined modifications, etc.

[0048] While various embodiments incorporating the teachings of the present invention have been shown and described in detail herein, those skilled in the art can readily devise many other diverse embodiments which still incorporate these teachings. Thus, while the foregoing is directed to various embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof. Accordingly, the appropriate scope of the present invention should be determined according to the following claims.

Claims

1. An integrated outflow tube balloon, a flexible tubular polymer layer having a distal end and a proximal end, the flexible tubular polymer layer having an outer surface and an inner surface; one or more openings at a proximal end, the one or more openings extending from the outer surface to the inner surface; a slot extending from the proximal end to the proximal end of one of the one or more openings; a distal end configured to be disposed over the expandable housing; and an integrated outflow tube balloon including:

2. The integrated outflow tube balloon of claim 1 , wherein the distal end is configured as an inflow mesh.

3. 1. An outflow tube assembly comprising: an expandable housing defining an inlet and an outlet; an inner coating disposed on an inner surface of the expandable housing between the inlet and the outlet; 3. The integrated outflow tube balloon of claim 1 or 2, wherein a portion of the integrated outflow tube balloon is operably coupled to the expandable housing and / or the inner coating. an outflow tube assembly.

4. The outflow tube assembly of claim 3 , wherein the housing includes a filter portion at the inlet.

5. A medical device comprising: a flexible tubular member; 5. The outflow tube assembly of claim 3 or 4, wherein the outflow tube assembly has a distal end and a proximal end, the distal end and the proximal end being operatively coupled to the flexible tubular member.

2. A medical device, comprising:

6. The medical device of claim 5 , further comprising an impeller disposed within the outflow tube assembly.

7. 1. A method of manufacturing a device, comprising: creating a first subassembly by providing an inner coating on a mandrel; creating a second subassembly by providing an expandable housing over the inner coating; creating a third subassembly by placing an integral outflow tubing balloon over the housing and inner coating; forming a device by bonding (e.g., by heat welding) the inner coating and housing to a portion of the integrated outflow tubing balloon, and optionally removing a portion of the integrated outflow tubing balloon to form an inflow mesh; removing the device from the mandrel; A method comprising:

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