Support catheter with enhanced torque response and high pushability

Abstract

A support catheter may be used in conjunction with a guidewire or other medical device. The support conduit may be adapted to provide both high pushability and good torque response. The elongate shaft of the support catheter may include a polymeric inner layer, a stainless steel braid layer disposed on the polymeric inner layer, and a polymeric blend layer directly pressed on the stainless steel braid layer. The configuration of the elongate shaft may provide the support conduit with a pushability value of at least 900 g / cm and a torque response value of less than 300 degrees.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 354,732, filed on June 23, 2022, entitled Support Catheter With Enhanced Torque Response and High Pushability, which is incorporated herein by reference. Technical Field

[0002] The present invention relates to medical devices. More particularly, the present invention relates to medical devices, such as support catheters, that provide both good torque response and high pushability. Background Art

[0003] A wide variety of medical devices have been developed for medical uses, e.g., for accessing a body cavity and interacting with fluids and structures in a body cavity. For example, a catheter can provide access to a remote location within the vascular system. Such a catheter may be able to provide support for other medical devices, provide a flow path for fluid delivery to a remote target site, or provide a means for performing other therapeutic and / or diagnostic actions. Summary of the invention

[0004] The present invention provides designs, materials, manufacturing methods and use alternatives for medical devices. A support catheter can be used in combination with a guidewire to provide additional support when attempting to pass through a CTO (chronic total occlusion) when treating peripheral arterial disease. The support catheter can be adapted to provide both high pushability and good torque response. The support catheter can include a polymer inner layer, a braided layer (such as, stainless steel braided filaments) disposed on the polymer inner layer, and a polymer outer layer, such as a polymer blended layer directly extruded on the braided layer. As a result, the support catheter can exhibit both good pushability and good torque response.

[0005] One example is a support catheter comprising an elongated shaft extending from a proximal region to a distal region. The elongated shaft comprises a polymer inner layer extending from the proximal region to the distal region; a stainless steel braided layer outside the polymer inner layer and extending from the proximal region to the distal region; and a polymer blended outer layer partially embedded in the stainless steel braided layer. The polymer blended outer layer is formed of a blend of polyether block amide (PEBA) polymers. The elongated shaft is adapted to provide a pushability value of at least 900 g / cm and a torque response value of less than 300 degrees.

[0006] Alternatively or additionally, the pushability value may be at least 1000 g / cm.

[0007] Alternatively or additionally, the torque response value may be less than 200 degrees.

[0008] Alternatively or additionally, the torque response value may be less than 100 degrees.

[0009] Alternatively or additionally, the support catheter further comprises a distal tip forming a butt joint with the distal end of the elongated shaft.

[0010] Alternatively or additionally, the braid extends along the entire length of the elongate shaft to the butt joint.

[0011] Alternatively or additionally, the support catheter further comprises a first radiopaque marker band located proximal to the docking joint and a polymer sleeve spanning the docking joint. The polymer sleeve extends over and surrounds the first radiopaque marker band and the distal tip.

[0012] Alternatively or additionally, the support catheter further comprises a second radiopaque marker band proximal to and spaced apart from the first radiopaque marker band. The outer layer is reflowed around the second radiopaque marker band such that the second radiopaque marker band is embedded in the outer layer, wherein the outer layer contacts the proximal annular surface and the distal annular surface of the second radiopaque marker band.

[0013] Alternatively or additionally, the outer diameter of the second radiopaque marker band is greater than the outer diameter of the outer layer just proximal and distal to the second radiopaque marker band.

[0014] Alternatively or additionally, the polymer blend outer layer comprises Care ME71 and Blend of Care ML 18.

[0015] Alternatively or additionally, the support catheter includes one of a large support catheter suitable for accommodating a 0.035-inch guidewire, a medium support catheter suitable for accommodating a 0.018-inch guidewire, and a small support catheter suitable for accommodating a 0.014-inch guidewire, wherein the large support catheter is suitable for allowing the medium support catheter or the small support catheter to be advanced within the large support catheter.

[0016] Alternatively or additionally, the polymer inner layer comprises a two-layer structure having a perfluorinated inner layer and a PEBA outer layer.

[0017] Another example is a support catheter. The support catheter includes a slender shaft having a proximal end and a distal end. The slender shaft includes a perfluoro inner layer extending continuously from the proximal end to the distal end; a stainless steel braided layer extending continuously from the proximal end to the distal end outside the perfluoro inner layer; and a polymer outer layer extending continuously from the proximal end to the distal end. The polymer outer layer surrounds and is partially embedded in the stainless steel braided layer. The polymer outer layer includes Care PEBA polymer blend. The distal tip is joined to the elongated shaft at a butt joint at the distal end of the elongated shaft. The elongated shaft is adapted to provide a pushability value of at least 900 g / cm and a torque response value of less than 300 degrees.

[0018] Alternatively or additionally, the pushability value may be at least 1000 g / cm.

[0019] Alternatively or additionally, the torque response value may be less than 200 degrees.

[0020] Alternatively or additionally, the torque response value may be less than 100 degrees.

[0021] Alternatively or additionally, the support catheter includes a polymer bonding layer disposed between the perfluorinated inner layer and the stainless steel braiding layer.

[0022] Alternatively or additionally, the support catheter includes a first radiopaque marker band located proximal to the docking joint and a polymer sleeve spanning the docking joint. The polymer sleeve extends over and around the first radiopaque marker band and the distal tip.

[0023] Alternatively or additionally, the support conduits are packaged in a linear orientation so as to avoid providing bending deformations to the support conduits.

[0024] Alternatively or additionally, the support catheter includes one of a large support catheter adapted to accommodate a 0.035 inch guidewire, a medium support catheter adapted to accommodate a 0.018 inch guidewire, and a small support catheter adapted to accommodate a 0.014 inch guidewire.

[0025] Alternatively or additionally, the outer layer comprises Care ME71 and Care ML18, and wherein the large support catheter has a polymer blend outer layer comprising a first ratio of Care ME71 and Care ML 18; The mid-support catheter has a polymer blend outer layer comprising a second ratio blended Care ME71 and Care ML 18; and the small support catheter has a polymer blend outer layer comprising a third ratio blended Care ME71 and Care ML 18.

[0026] Alternatively or additionally, the large support catheter is adapted to allow any of the medium support catheter and the small support catheter to be advanced within the large support catheter.

[0027] Another example is a support catheter comprising an elongated shaft extending from a proximal end to a distal end. The elongated shaft comprises a polymer inner layer extending continuously from the proximal end to the distal end; a braided layer, the braided layer surrounds the polymer inner layer and extends continuously from the proximal end to the distal end; and a polymer blended outer layer extending continuously from the proximal end to the distal end. The polymer blended outer layer surrounds and is partially embedded in the braided layer. The polymer blended outer layer comprises a blend of polyether block amide (PEBA) polymers. The distal tip is fixed to the distal end of the elongated shaft via a butt joint. A plurality of radiopaque marker bands are disposed in a distal region proximal to the butt joint. The support catheter is adapted to provide a pushability value of at least 900 g / cm and a torque response value of less than 300 degrees.

[0028] Alternatively or additionally, the pushability value may be at least 1000 g / cm.

[0029] Alternatively or additionally, the torque response value may be less than 200 degrees.

[0030] Alternatively or additionally, the torque response value may be less than 100 degrees.

[0031] Alternatively or additionally, the support catheter includes a polymer sleeve spanning the docking joint.The polymer sleeve extends over and surrounds the distal tip and the distal tip of the most distal one of the plurality of radiopaque marker bands.

[0032] Alternatively or additionally, the plurality of radiopaque marker bands include a proximal one of the plurality of radiopaque marker bands located proximal to a distal-most one of the plurality of radiopaque marker bands. The polymer blend outer layer is backflowed around the proximal one of the plurality of radiopaque marker bands such that the proximal one of the plurality of radiopaque marker bands is embedded in the polymer blend outer layer, wherein the polymer blend outer layer contacts the proximal annular surface and the distal annular surface of the proximal one of the plurality of radiopaque marker bands.

[0033] Alternatively or additionally, the polymer blend outer layer comprises Care ME71 and Blend of Care ML 18.

[0034] The above summary of some embodiments is not intended to describe each disclosed embodiment or every implementation of the present invention. The following figures and detailed description more particularly exemplify these embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The present invention may be more fully understood by considering the following detailed description of various embodiments of the invention taken in conjunction with the accompanying drawings, in which:

[0036] Figure 1is a side view of an illustrative support catheter;

[0037] Figure 2 yes Figure 1 an enlarged cross-sectional view of a portion of an illustrative support conduit;

[0038] Figure 3 yes Figure 1 an enlarged view of a portion of an illustrative support conduit;

[0039] Figure 4 is formed Figure 1 a partial cross-sectional view of a portion of an elongated shaft of an illustrative support catheter;

[0040] Figure 5 is formed Figure 1 a side view of a portion of a braided layer of a portion of an illustrative support catheter;

[0041] Figure 6 It includes a packaging structure and a Figure 1 A schematic diagram of an illustrative support catheter assembly;

[0042] FIG7 is a side view of a prior art support conduit;

[0043] 7A and 7B are cross-sectional views of the prior art support conduit of FIG. 7 ;

[0044] FIG8 is a side view of a prior art support conduit;

[0045] 8A, 8B, 8C and 8D are cross-sectional views of the prior art support catheter of FIG. 8;

[0046] Fig. 9 is a graph providing experimental results; and

[0047] Fig.10 It is a graph providing the experimental results.

[0048] Although the present invention is suitable for various modifications and alternative forms, its specific details have been shown in the drawings by way of example and will be described in more detail. However, it should be understood that the present invention is not intended to limit the various aspects of the present invention to the specific embodiments described. On the contrary, it is intended to cover all modifications, equivalents and substitutes that fall within the spirit and scope of the present invention. DETAILED DESCRIPTION

[0049] For the following defined terms, these definitions shall apply unless a different definition is given in the claims or elsewhere in this specification.

[0050] All numerical values ​​herein are assumed to be modified by the term "about", whether or not expressly indicated otherwise. The term "about" generally refers to a range of numbers that one skilled in the art would consider equivalent to the cited number (i.e., having the same function or result). In many cases, the term "about" may include numbers rounded to the nearest significant figure.

[0051] The recitation of numerical ranges by endpoints includes all numbers within that range (eg, 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5).

[0052] As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term "or" is generally employed in its sense including "and / or" unless the content clearly dictates otherwise.

[0053] The following detailed description should be read with reference to the drawings, in which similar elements in different drawings have the same reference numerals. The drawings, which are not necessarily drawn to scale, depict illustrative embodiments and are not intended to limit the scope of the invention.

[0054] In some cases, a guidewire may be used to pass through a CTO (complete chronic occlusion) when treating peripheral arterial disease. This may include pointing the guidewire toward a lesion at the ostium without entering a side branch. The guidewire may be pointed toward a specific vessel with a sharp exit angle for entry. A physician or other professional may wish to find a soft spot on the lesion cap to allow the guidewire to pass through the lesion more easily. In some cases, the guidewire may be pointed to help the guidewire reenter the lumen with a subintimal crossing technique.

[0055] In some cases, a physician or other professional may wish to use a support catheter with a guidewire to provide additional support for the guidewire. During surgery, the support catheter may be twisted to help guide the guidewire to the intended vessel and find a soft spot on the lesion cap for crossing. Therefore, a highly controllable support catheter that can provide a 1:1 torque response is helpful. Having high pushability is also required. Many catheters have good torque response. Many catheters have good pushability. However, these catheters are usually a trade-off between these competing properties and cannot provide a combination of good torque response and good pushability in a single catheter.

[0056] Figure 1It is a side view of an illustrative support conduit 10. As will be discussed, the illustrative support conduit 10 is suitable for providing both good torque response and good pushability. Therefore, the support conduit 10 can be considered to be well-equipped, for example, to be used for passing CTO (chronic total occlusion) together with a guide wire. In some cases, the support conduit 10 provides a pushability value of at least 900 grams / centimeter (g / cm). In some cases, the support conduit 10 provides a pushability value of at least 1000g / cm. The support conduit 10 can also provide a torque response value (hysteresis) less than 300 degrees. In some cases, the support conduit 10 can provide a torque response value less than 200 degrees. In some cases, the support conduit 10 can provide a torque response value less than 100 degrees. The test for determining the pushability value and the torque response value will be described in the experimental section below.

[0057] The support catheter 10 includes an elongated shaft 12 extending from a proximal region 14 to a distal region 16. The proximal region 14 includes a catheter hub 18 having a strain relief 20 fixedly attached to the proximal region 14, wherein the elongated shaft 12 extends distally from the proximal region 14. In some cases, the strain relief 20 can be integrally molded as a part of the catheter hub 18. The catheter hub 18 also includes a Luer connector 22, which is adapted to allow various devices, such as fluid lines, to be fluidly coupled to the catheter hub 18. The catheter hub 18 defines a lumen 24 extending through the catheter hub 18. In some cases, the lumen 24 is aligned with the lumen ( Figure 1 The lumen of the elongated shaft 12 may extend to the distal end of the elongated shaft 12. The lumen 24 (and the aforementioned lumens extending through the elongated shaft 12) is adapted to receive a guide wire 26, which can be seen entering the catheter hub 18 and exiting at the distal end 28 of the elongated shaft 12.

[0058] The distal region 16 of the elongated shaft 12 includes a distal tip 30, which joins the elongated shaft 12 at a butt joint 32. In some cases, the distal region 16 can be linear so that the central axis through the distal tip 30 is coaxial with the central axis of the proximal region 14 of the elongated shaft 12. In some cases, as shown in the figure, the distal region can have a curved profile to help support the steerability of the catheter. In some cases, the central axis of the distal tip 30 extends at an acute angle to the central axis of the proximal region 14 located proximal to the bend in the distal region 16. In some cases, the acute angle can be, for example, about 20 degrees, about 40 degrees, about 45 degrees, or about 48 degrees. In some cases, the support catheter 10 includes a plurality of marker bands 34, such as three spaced apart marker bands marked as 34a, 34b, and 34c, respectively. The marker band 34 can be formed by any radiopaque material, such as tungsten, platinum, or gold. The marker bands 34 can be formed to have any desired length and any desired spacing between the individual marker bands 34. In some cases, each of the marker bands 34 can have a length of 1 mm and can have a thickness of 0.001 inches. The marker bands 34 can each be spaced 5 centimeters (cm) apart along the distal region 16 of the elongated shaft. The most distal marker band 34c can be located just proximal to the butt joint 32.

[0059] In some cases, one or more of the marker bands 34 may be subjected to edge smoothing or swaging. This is a process in which a heat shrink polymer tube is placed over the marker bands 34 and sufficient heat is applied to soften the polymer layer beneath the elongated shaft 12 so that the marker bands 34 are at least partially pushed into the polymer layer beneath the elongated shaft 12 by the radially inward force of the heat shrink polymer tube, thereby reducing the profile of the marker bands 34. In some cases, a polymer sheath may extend over the butt joint 32 and the marker bands 34c to reinforce the butt joint 32. Figure 2 yes Figure 1 , which shows a polymer sheath 36 extending over the dock connector 32. The polymer sheath 36 can extend proximally of the dock connector 32 and surround a portion of the distal region 16 of the slender shaft 12 (e.g., the distal extent of the slender shaft 12). In addition, the polymer sheath 36 can extend distally of the dock connector 32 and surround the distal tip 30. In some cases, the polymer sheath 36 can also extend over the distal-most marker band 34c. In some cases, this can help encapsulate the distal edge 38a and proximal edge 38b of the marker band 34c and thereby prevent accidental tissue damage and / or snagging on another medical device that may otherwise be caused by the edges 38a and 38b. The polymer sheath 36 can be formed from any suitable polymer. In some cases, the polymer sheath 36 can be made of Materials such as but not limited to 72D or maybe Material.

[0060] In some cases, the marker bands 34 that are not covered by the polymer sheath 36, such as the proximal-most marker band 34a and the middle marker band 34b, may be edge smoothed. Edge smoothing is a process in which a heat shrink polymer tube is placed over the marker band 34 and sufficient heat is applied to soften the polymer layer underneath the elongated shaft 12 so that the marker band 34 is at least partially pushed into the softened material of the elongated shaft 12 by the radially inward force of being swaged or crimped onto the elongated shaft 12. In some cases, this may cause the outer layer of the elongated shaft 12 to flow back partially around the distal edge 38a and / or the proximal edge 38b of the marker band 34, thereby also helping to reduce the overall radial profile of the marker band 34 relative to the outer surface of the elongated shaft 12.

[0061] Figure 3 Shows Figure 1 , which shows a heat shrink polymer segment 40 (shown in phantom) extending through the marker band 34. In this view, the heat shrink polymer segment 40 has been heat shrunk, which helps to partially reflow the outer surface of the slender shaft 12 and thus reduce the overall radial profile of the marker band 34 relative to the outer surface 42 of the slender shaft 12. For example, in one instance, the outer diameter D of the marker band 34 can be approximately 0.0553 to 0.0576 inches, while the outer diameter OD of the slender shaft 12 of the support catheter (i.e., the large support catheter) can be a constant diameter along the entire length of the slender shaft (except below the marker band 34), which is approximately, for example, 0.0545±0.002 inches. In another instance, the outer diameter D of the marker band 34 can be about 0.0342 to 0.0362 inches, while the outer diameter OD of the elongated shaft 12 of the support catheter (i.e., the medium support catheter) can be a constant diameter along the entire length of the elongated shaft (except below the marker band 34), which is about, for example, 0.0335 ± 0.002 inches. In yet another instance, the outer diameter D of the marker band 34 can be about 0.0321 to 0.0341 inches, while the outer diameter OD of the elongated shaft 12 of the support catheter (i.e., the small support catheter) can be a constant diameter along the entire length of the elongated shaft (except below the marker band 34), which is about, for example, 0.0310 ± 0.002 inches. Similarly, the inner diameter of the marker band 34 after being swaged, crimped, or otherwise secured around the outer layer of the elongated shaft 12 can be less than the outer diameter OD of the outer layer of the elongated shaft 12 just proximal and distal to the marker band 34.

[0062] In some cases, the heat shrink polymer segment 40 can then be removed from the support catheter 10, leaving the circumferential outer surface of the marker band 34 exposed from and not covered by the elongated shaft 12. In some cases, it is contemplated that the heat shrink polymer segment 40 can remain as part of the support catheter 10, extending over the outer surface of the marker band 34 and extending proximally and distally beyond the marker band 34. When the outer layer of the elongated shaft 12 flows back around the proximal and distal edges of the marker band 34, the polymer material of the outer layer of the elongated shaft 12 can contact and substantially cover the proximal and distal annular surfaces of the marker band 34, except for the portion that radially extends beyond the outer diameter OD of the elongated shaft 12. In other words, the outer diameter OD of the elongated shaft 12 just proximal and distal to the marker band 34 (i.e., at the proximal and distal edges of the marker band 34) can be greater than the inner diameter of the marker band 34, such that the outer layer of the elongated shaft 12 is juxtaposed with the proximal and distal annular surfaces of the marker band 34.

[0063] Figure 4 is a partial cross-sectional view of the elongated shaft 12. The cross-sectional view can be taken at any location along the elongated shaft 12 because, in some cases, the elongated shaft 12 has the same configuration along the entire length of the elongated shaft 12, which extends between the catheter hub 18 and the butt connector 32 that joins the distal tip 30 to the elongated shaft 12. In some cases, along the length of the elongated shaft 12, the elongated shaft 12 has the same dimensions, such as a constant inner diameter (ID) and a constant outer diameter (OD) along the entire length of the elongated shaft 12 from the catheter hub 18 to the butt connector 32, and therefore has the same wall thickness for each of the layers that form the elongated shaft 12.

[0064] In some cases, the support catheter 10 can be made into a variety of sizes (e.g., outer diameter), which can be referred to as a large support catheter, a medium support catheter, and a small support catheter for ease of discussion. In some cases, the large support catheter can be adapted to have a cavity large enough to allow a medium support catheter or a small support catheter to extend in the large support catheter. In other words, the diameter of the cavity of the large support catheter can be greater than the outer diameter of both the medium support catheter and the small support catheter. This can be achieved by having a constant size (e.g., constant outer diameter and / or constant inner diameter) of each of the dimensions of the support catheter 10 along the length of the elongated shaft 12, and therefore not having any taper along the length of the elongated shaft 12 (except for the tapered outer diameter of the distal top at the extreme distal end of the support catheter) Each of the dimensions of the support catheter 10 promotes. In some cases, for example, a physician or other professional may be using a small support catheter or a medium support catheter to provide support for a guidewire, such as a guidewire 26, in an attempt to pass through the occlusion, and it can be determined that additional support will be helpful. In this case, the physician or other professional may decide to temporarily withdraw the small support catheter or the medium support catheter from the guidewire, advance the large support catheter over the guidewire, and then advance the previously used small support catheter over the guidewire and through the lumen of the large support catheter. The outer diameter of the large support catheter, which may be a constant diameter along the entire length of the elongated shaft, may be, for example, about 0.0545 ± 0.002 inches. The outer diameter of the medium support catheter, which may be a constant diameter along the entire length of the elongated shaft, may be, for example, about 0.0335 ± 0.002 inches. The outer diameter of the small support catheter, which may be a constant diameter along the entire length of the elongated shaft, may be, for example, about 0.0310 ± 0.002 inches.

[0065] The support conduit can be adapted to be compatible with a specific guide wire size. For example, a large support conduit can have a lumen diameter of about 0.037 inches, to be suitable for accommodating a guide wire of 0.035 inches therethrough. A medium support conduit can have a lumen diameter of about 0.019 inches, to be suitable for accommodating a guide wire of 0.018 inches therethrough, and a small support conduit can have a lumen diameter of about 0.015 inches, to be suitable for accommodating a guide wire of 0.014 inches therethrough. Therefore and in some cases, a large support conduit can have a total inner diameter (ID) of at least 0.035 inches, such as, 0.037 inches or larger or 0.0385 inches or larger ID. A medium support conduit can have a total ID of at least 0.018 inches, such as, 0.019 inches or larger or 0.0205 inches or larger ID. A small support conduit can have a total ID of at least 0.014 inches, such as, 0.015 inches or larger or 0.0165 inches or larger ID.

[0066] The support catheter 10 can have a variety of different lengths. For example, a large support catheter (suitable for use with a 0.035 inch guide wire) can have a length of 150 centimeters (cm), a length of 135 cm, a length of 90 cm, or a length of 65 cm. A medium support catheter (suitable for use with a 0.018 inch guide wire) can have a length of 150 cm, a length of 135 cm, or a length of 90 cm. A small support catheter (suitable for use with a 0.014 inch guide wire) can have a length of 150 cm, a length of 135 cm, or a length of 90 cm. The length can be measured from the most distal point on the distal tip 30 to the position where the elongated shaft 12 meets the strain relief 20. These are just examples.

[0067] The wall thickness of the elongated shaft 12 of the large support conduit, which may be a constant thickness along the entire length of the elongated shaft, may be, for example, about 0.00825 ± 0.0002 inches. The wall thickness of the elongated shaft 12 of the medium support conduit, which may be a constant thickness along the entire length of the elongated shaft, may be, for example, about 0.00675 ± 0.0002 inches. The wall thickness of the elongated shaft 12 of the small support conduit, which may be a constant thickness along the entire length of the elongated shaft, may be, for example, about 0.0075 ± 0.0002 inches.

[0068] The elongated shaft 12 may include an inner polymer layer 44 that defines a lumen 46 extending therethrough. It should be understood that the lumen 46 may be coaxially aligned with the lumen 24 extending through the catheter hub 18 and thus allow a device, such as, but not limited to, a guidewire 26 to extend all the way through the support catheter 10. This also means that, if necessary, fluid may be provided through the support catheter 10 by attaching an appropriate fluid source to the Luer connector 22. In some cases, the inner polymer layer 44 is a double-layer structure, including a first layer 48 and a second layer 50 surrounding the first layer 48. In some cases, the first layer 48 may be formed of a lubricating material, such as a perfluorinated material. As an example, the first layer 48 may be formed of PTFE (polytetrafluoroethylene). The second layer 50 may be formed of any suitable polymer, and in some cases may be used as a bonding layer between the first layer 48 and the polymer in the outer layer 54. In some cases, the second layer 50 may be formed of a polyether block amide (PEBA), such as PEBAX 72D. In some cases, second layer 50 may be formed of similar materials as outer layer 53, such as, CARE ME71 and CARE ML18, as discussed below. The first layer 48 can have an inner diameter ranging from 0.036 to 0.040 inches for large support conduits, 0.018 to 0.022 inches for medium support conduits, and 0.015 to 0.018 inches for small support conduits, respectively. The second layer 50 can have an outer diameter of about 0.0545 ± 0.0007 inches for large support conduits, about 0.0335 ± 0.0005 inches for medium support conduits, and about 0.0310 ± 0.0007 inches for small support conduits, respectively.

[0069] The elongated shaft 12 includes a braid 52 disposed on the inner polymer layer 44. In some cases, the filaments of the braid 52 are formed of a stainless steel material. As an example, the braid 52 can be formed of 304V stainless steel. The braid 52 can be formed of one or more flat bands, which can be woven in a 1×1 manner, a 2×2 manner, a 3×3 manner, or a 4×4 manner. The braid 52 can be formed of a flat stainless steel band having a thickness range of 0.0007 inches to 0.001 inches and a width range of 0.003 inches to 0.005 inches. In one example, the braid 52 can be formed of a 304V stainless steel band having a thickness of 0.0007±0.0002 inches and a width of 0.005±0.0005 inches. In other cases, the filaments of the braid 52 can have a circular cross-section. The braid can be formed of any number of flat bands, such as 32 bands, with 16 bands extending in each spiral direction. For example, the braid can have a pick count of about 60 to about 80, or about 65 to about 80, about 70 to about 80, or about 75. The pick count can be constant along the entire length of the braid, extending along the entire length of the elongated shaft 12 from the proximal end of the elongated shaft 12 to the distal end of the elongated shaft 12 at the butt joint 32. In some cases, the 304V stainless steel strip can have a breaking load in the range of 0.942 pounds (lbs.) to 1.295 pounds. This is just one example, as other stainless steel strips can be used.

[0070] The elongated shaft 12 includes an outer polymer layer 54. In some cases, the outer polymer layer 54 can be a blend of two or more different polymers. In some cases, the outer polymer layer 54 can be a blend of two or more polyether block amide (PEBA) polymers. The outer polymer layer 54 can be directly extruded onto the braid 52. In some cases, the outer polymer layer 54 can be a continuous extrusion extending from the hub assembly 18 to the butt joint 32 adjacent to the distal tip 30 along the entire length of the elongated shaft 12. The polymer material and / or blend composition of the outer polymer layer 54 can be uniform along the entire length of the outer polymer layer 54 from the hub assembly 18 to the butt joint 32 adjacent to the distal tip 30. In some cases, this helps to embed the outer polymer layer 54 at least partially into the braid 52, thereby improving the performance of the supporting catheter 10. In some cases, extruding the outer polymer layer 54 directly onto the braid 52 can help to partially embed the braid 52 into the inner polymer layer 44 (e.g., the bonding layer 50 of the inner polymer layer). In some cases, extruding outer polymer layer 54 directly onto braided layer 52 may help bond portions of outer polymer layer 54 that flow through gaps between strands of braided layer 52 directly to bonding layer 50 of inner polymer layer 44 .

[0071] In some cases, suitable PEBA polymers are available from Evonik Operations GmbH as As an example, the outer polymer layer 54 may be CAREME71 and CARE ML18 blends. For example, materials can be selected based on their relative stiffness. In some cases, CARE ML 18 is added to polymer blends to help provide stiffness while CARE ME71 helps provide flexibility.

[0072] In some cases, the outer polymer layer 54 may have a first blend of PEBA polymers to be included in the large support conduits. For example, the outer polymer layer 54 may have a second blend of PEBA polymers to be included in the medium support conduits. In some cases, the outer polymer layer 54 may have a third blend of PEBA polymers to be included in the small support conduits. In some cases, the first blend, the second blend, and the third blend may individually refer to a combination of the same PEBA polymers, but in which the PEBA polymers have different relative concentrations. In some cases, the first blend, the second blend, and the third blend may refer to a combination of the same PEBA polymers, which have the same or different same concentrations, where the relative additives used in each of the blends vary. In some cases, the first blend, the second blend, and the third blend may individually refer to a combination of different PEBA polymers that form the outer polymer layer 54.

[0073] In some cases, outer polymer layer 54 may be composed primarily of A blend of CARE ME71 was formed having the following composition, specifically for large support catheters (which are suitable for use with 0.035 inch guidewires):

[0074] In some cases, outer polymer layer 54 may be composed primarily of A blend of CARE M118 is formed, which has the following composition, particularly for medium support catheters (which are suitable for use with 0.018 guidewires) and small support catheters (which are suitable for use with 0.014 inch guidewires):

[0075] Figure 5 Further details about the braid 52 are provided. The braid 52 includes a total of thirty-two filaments, sixteen of which extend in a first helical direction and sixteen of which extend in a second helical direction opposite to the first helical direction. As can be seen, the filaments are wound in a two-by-two manner. For illustration, see the first filament 56 and the second filament 58, each of which extends in the first helical direction; and the third filament 60 and the fourth filament 62, each of which extends in the second helical direction. The first filament 56 crosses over both the third filament 60 and the fourth filament 62, and then passes under the next two crossing filaments (not labeled). The second filament 58 passes under the third filament 60 (and the previous crossing filament), and then passes over the fourth filament 62 (and the next crossing filament).

[0076] In some cases, for large support catheters, the individual filaments forming the braid 52 can be arranged steeply (at a 45 degree angle relative to the longitudinal axis 64 of the braid 52). This angle is shown with respect to the fourth filament 62, which can be considered to form an angle α (alpha) relative to the longitudinal axis 64. For large support catheters, the individual filaments forming the braid 52 can be arranged shallowly (at a 20 degree angle relative to the longitudinal axis 64 of the support catheter 10). In some cases, for both medium and small support catheters, the individual filaments forming the braid 52 can be arranged steeply (at a 40 degree angle relative to the longitudinal axis 64 of the support catheter 10). The braid 52 terminates at the butt joint 32 between the elongated shaft 12 and the distal tip 30, and therefore the distal tip is free of any braided structure.

[0077] Figure 6 6 is a schematic diagram of an assembly 66 including a support catheter 10 secured within a packaging structure 68. The packaging structure 68 includes a plurality of lugs 70 for retaining the support catheter 10 relative to the packaging structure 68. Although not shown, it is understood that the packaging structure 68 (and the support catheter 10) will be encapsulated within a material that maintains the sterility of the support catheter 10 within the material, but still allows the support catheter 10 to be sterilized within the material. In some cases, the support catheter 10 can be sterilized by subjecting the packaging structure 68 (and the support catheter 10 within the packaging structure 68) to, for example, ethylene oxide sterilization, although other sterilization processes are also contemplated.

[0078] The packaging structure 68 is configured to maintain the support catheter 10 in a linear configuration. It is noteworthy that in the case where the support catheter 10 includes a curved distal region, the curved distal region will be maintained in the packaging, while the other portion of the length of the elongated shaft will be maintained in a linear configuration in the packaging structure 68. Although many elongated structures, such as guidewires and catheters, can be packaged in a space-saving manner with at least a portion of the elongated structure rolled up, it has been found that in some cases, storing the elongated structure in a coiled manner may impart deformation to the elongated structure. Therefore, maintaining the support catheter 10 in a straight configuration can help eliminate any such deformation imparted to any component of the support catheter 10. As a result, the support catheter 10 is better able to meet its required pushability and torsional performance characteristics. Experimental Section

[0079] Several sizes of support catheters 10 were compared to similar sized support catheters currently available on the market. The large (0.035 inch OD) support catheter was compared to a similar sized support catheter available under the Navicross name having an angled tip, a length of 150 cm, and an overall OD of 0.035 inches. The medium (0.018 inch OD) support catheter was compared to a similar sized support catheter available under the CXI name having an angled tip, a length of 150 cm, and an overall OD of 0.018 inches. The small (0.014 inch OD) support catheter was compared to a similar sized support catheter available under the CXI name. About Figures 1 to 6 Each of the large, medium and small support catheters are shown and described.

[0080] The Navicross device is shown in FIG. 7 , which is a schematic side view of the device 80. FIG. 7A is a cross-sectional view, while FIG. 7B is a longitudinal cross-sectional view. The Navicross device 80 includes an elongated shaft 82 extending from an angled distal tip 84 to a catheter hub 86 including a strain relief 88. As shown in FIG. 7A , the elongated shaft 82 includes a braided layer 90 disposed between an inner layer 92 and an outer layer 94. As shown in FIG. 7B , the braided layer 90 is at least partially embedded within the inner layer 92. A marker band 96 is at least partially embedded in the outer layer 94. The following table provides additional details about the Navicross device 80:

[0081] The CXI device is shown in FIG8 , which is a schematic side view of the device 98. FIG8A , FIG8B , FIG8C , and FIG8D are cross-sectional views taken at various points along the device 98. The device 98 includes an elongated shaft 100 extending from an angled distal tip 102 to a catheter hub 104 including a strain relief 106. As shown in the cross-sectional view, the elongated shaft 100 includes an inner layer 108, a braided layer 110 at least partially embedded in the inner layer 108, another layer 112 located outside the inner layer 108, another layer 113 located outside the layer 112, and an outer layer 116 located outside the layer 114. FIG8B specifically shows a marker band 118, while FIG8C specifically shows a marker band layer 120. The following table provides additional details about the CXI device for a 0.018 inch OD size: process

[0082] The procedure for testing pushability is as follows. Pushability measures column stiffness and is similar to the clinical scenario. The distal tip of the catheter is pushed against the load cell until a force of 50 grams is applied. The slope of the force (measured at the load cell) and the distance traveled by the catheter provide a measure of pushability. A higher slope means the device has better column strength or pushability, and therefore a higher result number is better than a lower result number.

[0083] The process for testing torque response is as follows. The torque response test measures the torque transmission from the proximal end of the device being tested to the distal end of the device being tested. The catheter (device) is placed inside a 2D torque fixture on the IDTE 3000, where the proximal hub is attached to the proximal dynamic torque motor and the distal end is fixed to a rotational output sensor. The proximal dynamic torque motor rotates the proximal hub five (5) full rotations (e.g., 1,800 degrees of rotation), and at the same time, the rotational output sensor measures the output rotation at the distal end of the catheter shaft. The output of this test is the torque hysteresis, which is the delta difference between the rotation angle input (proximal end) and the rotation angle output (distal end). Lower result values ​​are better than higher result values. In other words, the output value of this test is the difference between the rotation input at the proximal end of the catheter shaft minus the rotation output at the distal end of the catheter shaft. result

[0084] Fig. 9 Graphs of thrust intervals for the support catheter of the present invention, tested in large (0.035 inch guidewire), medium (0.018 inch guidewire), and small (0.014 inch guidewire) sizes, and compared to a 0.014 inch OD CXI device, a 0.018 inch OD CXI device, and a 0.035 inch OD Navicross device. In each case, the support catheter of the present invention exhibited significantly greater thrust relative to competitive devices of the same size. For the 0.014 inch size, the support catheter of the present invention had a thrust of approximately 914 g / cm, while the corresponding CXI device had a thrust of only approximately 766 g / cm. The support catheter of the present invention had over 19% greater thrust. For the 0.018 inch size, the support catheter of the present invention had a thrust of approximately 1090 g / cm, while the corresponding CXI device had a thrust of only approximately 898 g / cm. The support catheter of the present invention had over 21% greater thrust. For the 0.035 inch size, the support catheter of the present invention has a thrust of about 958 g / cm, while the corresponding Navicross device has a thrust of only about 678 g / cm. The support catheter of the present invention has a thrust that is more than 41% higher.

[0085] Fig.10It is an interval diagram of the torque response of the support catheter of the present invention, which was tested in large size (0.035 inch guidewire), medium size (0.018 inch guidewire) and small size (0.014 inch guidewire), and compared with the CXI device of 0.014 inch OD, the CXI device of 0.018 inch OD and the Navicross device of 0.035 inch OD. In each case, the support catheter of the present invention shows a significantly lower torque response relative to the competitive device with the same size. For the size of 0.014 inch, the support catheter of the present invention has a torque response of about 267 degrees, while the corresponding CXI device has a torque response of about 465 degrees. For the size of 0.018 inch, the support catheter of the present invention has a torque response of about 192 degrees, while the corresponding CXI device has a torque response of about 322 degrees. For the size of 0.035 inch, the support catheter of the present invention has a torque response of about 77 degrees, while the corresponding Navicross device has a torque response of about 229 degrees.

[0086] The results show that the support catheter of the present invention has better pushability and better torque response than the competitive products tested, regardless of size. The support catheter of the present invention is significantly superior to the competitive devices.

[0087] The devices described herein and their various components may be manufactured according to essentially any suitable manufacturing technique, including molding, casting, machining, etc., or any other suitable technique. In addition, the various structures may include materials commonly associated with medical devices, such as metals, metal alloys, polymers, metal-polymer composites, ceramics, combinations thereof, etc., or any other suitable material. These materials may include transparent or translucent materials to facilitate visualization during surgery. Some examples of suitable metals and metal alloys include stainless steels, such as 304V, 304L, and 316LV stainless steel; low carbon steel; nickel-titanium alloys, such as linear elastic and / or superelastic nitinol; other nickel alloys, such as nickel-chromium-molybdenum alloys (e.g., UNS: N06625, such as 625, UNS:N06022, such as UNS:N10276, such as other alloys, etc.), nickel-copper alloys (e.g., UNS: N04400, such as 400, 400, 400, etc.), nickel-cobalt-chromium-molybdenum alloys (e.g., UNS: R30035, such as etc.), nickel-molybdenum alloys (e.g., UNS: N10665, such as ALLOY ), other nickel-chromium alloys, other nickel-molybdenum alloys, other nickel-cobalt alloys, other nickel-iron alloys, other nickel-copper alloys, other nickel-tungsten or tungsten alloys, etc.; cobalt-chromium alloys; cobalt-chromium-molybdenum alloys (e.g., UNS: R30003, such as etc.); platinum-rich stainless steel; combinations thereof; etc.; or any other suitable material.

[0088] Some examples of suitable polymers may include polytetrafluoroethylene (PTFE), ethylene tetrafluoroethylene (ETFE), fluorinated ethylene propylene (FEP), polyoxyethylene (POM, e.g., commercially available from DuPont ), polyether block esters, polyurethanes, polypropylene (PP), polyvinyl chloride (PVC), polyether esters (for example, commercially available from DSM Engineering Plastics ), ether- or ester-based copolymers (e.g., butylene phthalate / poly(alkylene ether) and / or other polyester elastomers such as those commercially available from DuPont ), polyamide (for example, commercially available from Bayer or commercially available from Elf Atochem ), elastomeric polyamides, block polyamide / ether, polyether block amide (PEBA, for example, available under the trade name Commercially available), ethylene-vinyl acetate copolymer (EVA), silicone, polyethylene (PE), High density polyethylene, Low-density polyethylene, linear low-density polyethylene (e.g. ), polyester, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polytrimethylene terephthalate, polyethylene naphthalate (PEN), polyetheretherketone (PEEK), polyimide (PI), polyetherimide (PEI), polyphenylene sulfide (PPS), polyphenylene oxide (PPO), poly(p-phenylene terephthalamide) (e.g., ), polysulfone, nylon, nylon-12 (such as commercially available from EMS American Grilon ), perfluoro(propyl vinyl ether) (PFA), ethylene vinyl alcohol, polyolefins, polystyrene, epoxy resins, polyvinylidene chloride (PVdC), polycarbonates, ionomers, biocompatible polymers, other suitable materials or mixtures, combinations, copolymers, polymer / metal composites, etc.

[0089] It should be understood that the present invention is in many respects merely illustrative. Changes may be made in details, particularly in matters of shape, size, and arrangement of steps, without exceeding the scope of the present invention. To the extent appropriate, this may include using any of the features of an example embodiment used in other embodiments. Of course, the scope of the present invention is defined by the language of the appended claims.

Claims

1. A support catheter, comprising: An elongated shaft extending from a proximal region to a distal region, the elongated shaft comprising: a polymer inner layer extending from the proximal region to the distal region; a stainless steel braid layer external to the polymer inner layer and extending from the proximal region to the distal region; and a polymer blend outer layer partially embedded in the stainless steel braid, the polymer blend outer layer comprising a blend of polyether block amide (PEBA) polymers; The elongated shaft is adapted to provide a pushability value of at least 900 g / cm and a torque response value of less than 300 degrees. 2 . The support catheter according to claim 1 , further comprising a distal tip, wherein the distal tip forms a butt joint with the distal end of the slender shaft.

3. The support catheter of claim 2, wherein the braided layer extends along the entire length of the elongated shaft to the butt joint.

4. The support conduit according to claim 2 or 3, further comprising: a first radiopaque marker band located proximal to the butt connector; as well as a polymer sleeve spanning the butt joint; Wherein the polymer sleeve extends over and surrounds the first radiopaque marker band and the distal tip.

5. A support catheter according to claim 4, further comprising a second radiopaque marker band proximal to and spaced apart from the first radiopaque marker band, wherein the outer layer flows back around the second radiopaque marker band so that the second radiopaque marker band is embedded in the outer layer, wherein the outer layer contacts the proximal annular surface and the distal annular surface of the second radiopaque marker band.

6. The support catheter of claim 5, wherein the outer diameter of the second radiopaque marker band is greater than the outer diameter of the outer layer just proximal and distal to the second radiopaque marker band.

7. A support catheter according to any one of the preceding claims, wherein the polymer blend outer layer comprises Care ME71 and Blend of Care ML 18.

8. A support catheter according to claim 7, wherein the support catheter comprises one of a large support catheter suitable for accommodating a 0.035-inch guide wire, a medium support catheter suitable for accommodating a 0.018-inch guide wire, and a small support catheter suitable for accommodating a 0.014-inch guide wire, wherein the large support catheter is suitable for allowing the medium support catheter or the small support catheter to be advanced within the large support catheter.

9. The support catheter according to any one of the preceding claims, wherein the polymer inner layer comprises a double layer structure having a perfluorinated inner layer and a PEBA outer layer.

10. A supporting conduit, comprising: An elongated shaft having a proximal end and a distal end, the elongated shaft comprising: a perfluorinated inner layer extending continuously from the proximal end to the distal end; a stainless steel braided layer, the stainless steel braided layer being outside the perfluoro inner layer and extending continuously from the proximal end to the distal end; and A polymer outer layer continuously extending from the proximal end to the distal end, the polymer outer layer surrounding and partially embedded in the stainless steel braided layer, the polymer outer layer comprising Care PEBA polymer blends; a distal tip joined to the elongated shaft at the distal end of the elongated shaft at a butt joint; The elongated shaft is adapted to provide a pushability value of at least 900 g / cm and a torque response value of less than 300 degrees.

11. The support catheter according to claim 10, further comprising a polymer bonding layer disposed between the perfluorinated inner layer and the stainless steel braided layer.

12. The support conduit according to claim 10 or 11, further comprising: a first radiopaque marker band located proximal to the butt connector; as well as a polymer sleeve spanning the butt joint; Wherein the polymer sleeve extends over and surrounds the first radiopaque marker band and the distal tip.

13. A support conduit according to any one of claims 10 to 12, wherein the support conduit is packed in a linear orientation so as to avoid providing bending deformation to the support conduit.

14. A support conduit, comprising: An elongated shaft extending from a proximal end to a distal end, the elongated shaft comprising: a polymer inner layer, the polymer inner layer extending continuously from the proximal end to the distal end; a braided layer surrounding the polymer inner layer and extending continuously from the proximal end to the distal end; and a polymer blend outer layer extending continuously from the proximal end to the distal end, the polymer blend outer layer surrounding and partially embedded in the braided layer, the polymer blend outer layer comprising a blend of polyether block amide (PEBA) polymers; a distal tip secured to the distal end of the elongated shaft via a butt joint; and a plurality of radiopaque marker bands disposed within the distal region proximal to the butt connector; The support conduit is adapted to provide a pushability value of at least 900 g / cm and a torque response value of less than 300 degrees.

15. The support conduit of claim 14, further comprising a polymer sleeve spanning the butt joint; Wherein the polymer sleeve extends over and surrounds a distal-most one of the plurality of radiopaque marker bands and the distal tip.

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