Catheter with spine reinforcement

Abstract

The thrombectomy catheter can have a body section with tailored, highly flexible properties to navigate tortuous paths and an expandable tip section for locally restricting / stopping flow. The catheter can include one or more spines extending the length of the elongate shaft, which can be interwoven with the shaft braid. The distal portion of the spine can be formed into a spine hoop as part of the distal hoop of the tip section. Alternatively, the spine can form a loop around the shaft braid. The spine can be made of metal, polymer, or fiber strands. Polymer spines can be formed using layered or coextrusion manufacturing methods. The support tube can have a polymer jacket or membrane disposed around at least a portion of the structure.

Description

[Technical Field]

[0001] FIELD OF THE INVENTION The present invention relates generally to devices and methods for removing acute occlusions from blood vessels during intravascular medical procedures. More particularly, the present disclosure relates to a retrieval aspiration catheter having spine reinforcement. [Background technology]

[0002] Aspiration and thrombectomy catheters and devices are often used for mechanical thrombectomy to perform endovascular interventions, such as in patients with conditions such as acute ischemic stroke (AIS), myocardial infarction (MI), and pulmonary embolism (PE). With conventional techniques, access to the neurovascular bed, in particular, has been difficult because the target vessels are small in diameter, far from the insertion site, and highly tortuous.

[0003] To effectively deliver devices to the small, highly branched cerebral arterial system, conventional catheters must balance many factors. The catheter must be flexible enough to track through the vasculature and withstand large bending strains, while also possessing axial stiffness to provide smooth, stable advancement along the path. Additionally, abrupt stiffness or geometric changes can hinder trackability, introduce significant stress concentrations, and increase the likelihood of device kinking or buckling.

[0004] Aspiration catheter designs must balance flexibility for delivery with adequate radial force and atraumatic deployment. Not only must the catheter elements withstand the large mechanical strains they are subjected to, but they must also generate sufficient radial force upon expansion to prevent collapse under the suction force of aspiration. Many flexible body designs have small diameters that cannot generate the required suction force, while designs with expandable members or separate aspiration extensions may lack the flexibility to navigate neurovasculature. Some designs for thrombectomy catheters can have difficulties related to insufficient tensile strength. In such scenarios, the catheter may lengthen or stretch during use, causing usability and durability issues. Other designs have increased the catheter's tensile strength but at the expense of lateral flexibility, making the catheter more difficult to navigate. Summary of the Invention [Means for solving the problem]

[0005] The present design aims to provide an improved retrieval catheter with an expandable tip that incorporates features to overcome the above-mentioned drawbacks.

[0006] The design herein may be for a spine reinforcement for a catheter that can provide localized flow restriction / stoppage within a target vessel. The catheter's spine can increase the catheter's tensile strength while maintaining lateral flexibility, which is particularly important. This allows the catheter to be sufficiently flexible to enable it to navigate highly tortuous areas of the anatomy, such as the neurovasculature, to reach an occlusive thrombus, while still maintaining its tensile strength. The spine may be either metallic or polymeric. Some spines may be interwoven with a braid. Interwoven spines can maintain the position of the spine during use when the product is bent. Furthermore, this locks the spine within the braid, preventing it from passing through a liner or jacket.

[0007] Disclosed embodiments may include a catheter. The catheter may include a proximal elongate shaft, which may include a longitudinal axis, a distal end, and a shaft braid. The catheter may also include a distal tip section with a tip braid terminating in a distal hoop. Further, the catheter may include a plurality of outer jackets disposed around the elongate shaft and the tip section. Additionally, the catheter may include one or more metal spines extending at least partially along the axial length of the catheter. The one or more metal spines may inhibit tensile elongation of the catheter. The catheter may include a distal hoop of the tip braid integrally formed with the wires of the shaft braid.

[0008] At least a portion of the one or more metal spines may be a shape memory alloy.

[0009] At least a portion of the one or more metal spines may be made from at least one of stainless steel, DFT, cobalt chrome, titanium alloy, or tungsten.

[0010] At least one of the one or more metal spines may be interwoven with the shaft braid.

[0011] At least one of the one or more metallic spines may have a proximal portion and a distal portion, and at least a portion of the proximal portion may include two or more adjacent parallel strands. The distal portion may form one or more of the distal hoops of the tip portion braid.

[0012] At least a portion of the one or more metallic spines may extend the entire axial length of the catheter.

[0013] At least a portion of the one or more metal spines may have a non-circular cross-section.

[0014] The one or more metal spines may further include a first spine and a second spine spaced 180 degrees apart.

[0015] At least a portion of the shaft braid and at least a portion of the tip braid may comprise different materials.

[0016] At least one of the one or more metal spines may include portions of different thicknesses.

[0017] The one or more metal spines may be external to the shaft braid.

[0018] The one or more metallic spines may further include a single spine attached at a termination point to one of the shaft braid or the tip braid.

[0019] Disclosed embodiments may include a catheter. The catheter may include an elongate tube having a longitudinal axis and a shaft braid, which may include a first set of helical wires braided with a second set of helical wires. The catheter may also include a distal tip section including a tip braid with a distal hoop at its distal end. In addition, the catheter may include a plurality of outer jackets disposed around the elongate tube and the tip section. Further, the catheter may include one or more polymer spines extending at least partially along the axial length of the catheter, the polymer spines inhibiting tensile elongation of the catheter. The first set of helical wires of the shaft braid may invert proximally to form a second set of helical wires of the shaft braid. The distal hoop of the tip braid may be integrally formed with the wires of the shaft braid.

[0020] At least a portion of the one or more polymer spines may comprise at least one of the following compositions: high density polyethylene, polyetherketone, ultra-high molecular weight polyethylene, aromatic polyamide, LCP liquid crystal polymer, nylon, or thermoset liquid crystal polyoxazole.

[0021] At least a portion of the one or more polymer spines may be laminated with the outer jacket.

[0022] At least a portion of the one or more polymer spines may be co-extruded with at least one of the outer jackets.

[0023] At least one of the one or more polymer spines may be interwoven with the shaft braid.

[0024] At least one of the one or more polymer spines may be inverted through the shaft braid or the tip braid at a spine loop to form two parallel strands.

[0025] At least a portion of one of the parallel strands may extend outside the shaft braid, and at least a portion of one of the parallel strands may extend inside the shaft braid.

[0026] Disclosed embodiments may include a method for constructing a catheter. The method may include disposing an inner liner around an application mandrel. The method may also include positioning one or more axial spines on an outer surface of the inner liner substantially parallel to the longitudinal axis. Furthermore, the method may include disposing a braided member around at least a portion of the inner liner on the application mandrel, the braided member having a proximal portion and a distal portion terminating in a plurality of distal hoops. Additionally, the method may include reflowing a series of proximal outer jackets to bond the catheter assembly. The method may also include loading a polymeric distal inner jacket around a reflow tool. Furthermore, the method may include removing the application mandrel and inserting the reflow tool and the polymeric distal inner jacket into the distal end of the catheter assembly. The method may include positioning a polymeric distal outer jacket around at least a distal portion of the catheter assembly on the reflow tool. The method may also include reflowing the polymeric distal inner jacket and the polymeric distal outer jacket onto the distal portion of the catheter assembly. Finally, the method may include removing the reflow tool.

[0027] The method may further include applying an inner hydrophilic coating to at least the interior of the distal portion of the catheter assembly.

[0028] The method may further include utilizing a polymer in at least a portion of the one or more spines having a melting temperature within approximately ±17 degrees of the melting temperature of the distal-most outer jacket of the catheter. The method may also include laminating at least a portion of the one or more spines with the outer jacket. The method may also include co-extruding at least a portion of the one or more spines into at least a portion of the outer jacket to form a layered structure.

[0029] The method may include inverting at least one of the one or more spines and looping it through an opening in the braided member.

[0030] The method may include utilizing a reflow tool having a flared distal end.

[0031] The method may include utilizing a polymer in at least a portion of one or more spines that has a melting temperature within approximately ±6 degrees of the melting temperature of the distal-most outer jacket of the catheter.

[0032] The method may include inverting a distal portion of one or more of the axial spines to form one or more of the distal hoops of the tip portion braid.

[0033] An exemplary catheter may include an elongate tube having a longitudinal axis and a shaft braid including a first set of helical wires braided with a second set of helical wires. The catheter may also include a distal tip section including a tip braid with a distal hoop at its distal end. The catheter may also include multiple outer jackets disposed around the elongate tube and tip section. There may be one or more polymer spines extending at least partially along the axial length of the catheter. The polymer spines may inhibit tensile elongation of the catheter. The first set of helical wires of the shaft braid may invert proximally to form a second set of helical wires of the shaft braid. The distal hoop of the tip braid may be integrally formed with the wires of the shaft braid.

[0034] An exemplary method for constructing a catheter may include placing an inner liner around an application mandrel. The method may also include positioning one or more axial spines outside an outer surface of the inner liner parallel to the longitudinal axis. Furthermore, the method may include placing a braided member around at least a portion of the inner liner on the application mandrel, the braided member having a proximal portion and a distal portion terminating in a plurality of distal hoops. Furthermore, the method may include reflowing a series of proximal outer jackets to bond the catheter assembly. The method may further include loading a polymeric distal inner jacket around a reflow tool. Additional steps may include removing the application mandrel and inserting the reflow tool and the polymeric distal inner jacket into the distal end of the catheter assembly. Furthermore, the method may include positioning a polymeric distal outer jacket around at least a distal portion of the catheter assembly on the reflow tool. The method may include reflowing the polymeric distal inner jacket and the polymeric distal outer jacket onto the distal portion of the catheter assembly. Additionally, the method may include removing the reflow tool. Finally, the method may include applying an inner hydrophilic coating to at least the interior of the distal portion of the catheter assembly. [Brief explanation of the drawings]

[0035] The above and further aspects of the present invention will be further discussed with reference to the following description in conjunction with the accompanying drawings, in which like numerals indicate like structural elements and features in the various drawings. The drawings are not necessarily to scale, focus instead being upon illustrating the principles of the present invention. The figures depict one or more implementations of devices of the present invention by way of example only, and not by way of limitation. [Figure 1] FIG. 1 is a side view of a catheter having a spine reinforcement with a distal portion of the spine forming one of the distal hoops of the tip section braid, according to an embodiment of the invention. [Figure 2] FIG. 1 is a side view of a catheter having a spine reinforcement with one of the metal spines interwoven with the shaft braid, according to an embodiment of the present invention. [Figure 3] 3 is a cross-sectional view of the catheter of FIG. 2 showing the position of the axial strands relative to the shaft braid, according to an embodiment of the present invention. [Figure 4] 3 is a cross-sectional view of the catheter of FIG. 2 showing the position of the axial strands relative to the shaft braid, according to an embodiment of the present invention. [Figure 5] FIG. 1 is a side view of a catheter having a spine reinforcement including a spine loop, according to an aspect of the present invention. [Figure 6] 6 is a cross-sectional view of the catheter of FIG. 5 showing the position of the axial strands relative to the shaft braid, according to an embodiment of the invention. [Figure 7] FIG. 1 is a side view of a catheter having a spine reinforcement including two spine loops spaced 180 degrees apart, according to an embodiment of the invention. [Figure 8] FIG. 1 is a side view of a catheter having a spine reinforcement including a single spline attached to the shaft braid, according to an aspect of the present invention. [Figure 9] 1 is an isometric view of a catheter having a spine loop with a self-expanding collapsible superbore (CSB) tip, according to an embodiment of the present invention. FIG. [Figure 10]FIG. 1 is an isometric view of a catheter having a spine loop with a thrombus-expanding low shear tip (LST) tip, according to an embodiment of the present invention. [Figure 11] FIG. 1 is a flow diagram illustrating the fabrication of a catheter with spine reinforcement by layering, according to an aspect of the present invention. [Figure 12] FIG. 1 is a flow diagram illustrating the manufacture of a catheter with spine reinforcement by coextrusion, according to an embodiment of the present invention. [Figure 13A] FIG. 1 is a front view of an application mandrel assembly for assembling a catheter having a spine reinforcement and a distal marker band, according to an aspect of the present invention. [Figure 13B] 10A-10C are side views illustrating the use of an application mandrel to assemble a catheter having a spine reinforcement and a distal marker band, according to an aspect of the present invention. [Figure 13C] 10A-10C are isometric views illustrating the use of an application mandrel to assemble a catheter having a spine loop and a distal marker band, according to an aspect of the present invention. [Figure 13D] FIG. 10 is an isometric view illustrating the use of an application mandrel to assemble a catheter having a spine hoop, according to an aspect of the present invention. [Figure 13E] FIG. 1 is an isometric view of a reflow tool used to manufacture a catheter having spine reinforcement, according to an aspect of the present invention. [Figure 13F] FIG. 1 is an isometric cutaway view of a reflow tool for inserting a distal inner jacket into a catheter having a spine reinforcement, according to an aspect of the present invention. [Figure 13G] FIG. 1 is an isometric view of a reflow tool for heating a distal inner jacket in a catheter having a spine reinforcement, according to an aspect of the present invention. [Figure 13H] FIG. 10 is an isometric view of a reflow tool being removed from a catheter having a spine reinforcement, in accordance with aspects of the present invention. [Figure 13I] FIG. 1 is a side cutaway view of a finished catheter having a spine reinforcement, according to an aspect of the present invention. [Figure 14A]FIG. 1 is a flow diagram summarizing steps for manufacturing a catheter having a polymer spine reinforcement according to an aspect of the present invention. [Figure 14B] FIG. 1 is a flow diagram summarizing steps for manufacturing a catheter having a polymer spine reinforcement according to an aspect of the present invention. [Figure 15A] FIG. 1 is a side view showing a flat spine end of a catheter having a spine reinforcement according to an aspect of the present invention. [Figure 15B] FIG. 1 is a side view showing a rass spine end of a catheter having spine reinforcement, according to an aspect of the present invention. [Figure 16] FIG. 10 is an enlarged view showing how the raspberry spine end of a catheter having spine reinforcement interacts with the braid at the braid crossover point, according to an embodiment of the present invention. [Figure 17A] FIG. 1 is a side view of a catheter having a spine reinforcement, showing the spine attached by adhesive fixation, according to an aspect of the present invention. [Figure 17B] FIG. 1 is a side view of a catheter with a spine reinforcement, showing the spine attached by an outer jacket fixation, in accordance with an aspect of the present invention. [Figure 18] FIG. 1 is a side view of a catheter having a spine reinforcement in which marker bands are used in attaching the spine, according to an aspect of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0036] As used herein, the term "about" or "approximately" in connection with any numerical value or numerical range indicates a suitable dimensional tolerance that enables a portion of a component or a collection of components to function for its intended purpose as described herein. More specifically, "about" or "approximately" may refer to a range of values ​​of ±20% of the recited value; for example, "about 90%" may refer to a range of values ​​of 71% to 99%.

[0037] As used herein, the terms "tubular" and "tube" are intended to be broadly construed and are not limited to right cylindrical structures, or structures that are strictly circular in cross section, or structures that are uniform in cross section throughout their length. For example, a tubular structure or tubular system is generally depicted as a substantially right cylindrical structure. However, a tubular system can have a tapered or curved outer surface without departing from the scope of the present disclosure.

[0038] An objective of at least some of the disclosed designs is to create a spine reinforcement for a catheter that can provide both localized flow restriction / blockage and high flexibility, allowing it to navigate tortuous regions of the vasculature within the outer catheter to reach occlusive thrombus. Such advantages may also be particularly beneficial in invasive stroke procedures, where blood vessels within the neurovascular bed are particularly thin, tortuous, and fragile. Consequently, the tailored axial and bending stiffness profiles of the expandable port tip can resist kinking and stiffness while tracking through these vessels. The tip can have a collapsed state, allowing the thrombectomy catheter to be compatible with relatively low-profile access sheaths and outer catheters, thereby facilitating and reliably closing a puncture wound in the patient's groin (in the case of femoral access). The expandable port can also include internal and / or external low-friction liners and an outer polymer jacket or membrane disposed around the support structure. These improvements can lead to safer and more rapid access to complex areas with catheters and other devices to more reliably remove blockages and reduce procedure times.

[0039] Another advantage of using and having a thrombectomy catheter delivered through an outer catheter is that if a thrombus advances to the distal end of the thrombectomy catheter, the thrombectomy catheter can be retracted through the outer catheter, leaving the outer catheter in place to maintain access at the target treatment location. While it is recognized that certain thrombi may require the outer catheter to be retracted along with the thrombus and inner thrombectomy catheter, the majority of the thrombus is likely to be removed through the inner thrombectomy catheter. This combination increases the likelihood that the lumen of the outer catheter is free of debris, reducing the risk that potential thrombus residue may become dislodged from the catheter during injection of contrast. With conventional catheters, users must remove the outer catheter and flush out any thrombus residue outside the body before injecting contrast, often at the expense of losing access to the target treatment location. At least some embodiments of the present invention provide a means for minimizing the number of catheter advancements required to treat a patient, thereby reducing the potential for vessel injury and the associated risk of vessel transection when multiple passes are required.

[0040] Specific embodiments of the present invention will now be described in detail with reference to the figures. Accessing various blood vessels within the vascular system, whether coronary, pulmonary, or cerebral, involves well-known procedural steps and uses many conventional, commercially available accessory products. These products, such as angiographic materials, rotating hemostatic valves, and guidewires, are widely used in laboratories and medical procedures. When these or similar products are used with the systems and methods of the present invention in the following description, their function and exact configuration will not be described in detail. The design may often include a polymer membrane cover / encapsulation and / or a polymer inner liner, which are typically not shown to clarify the underlying framework. While the description is often related to mechanical thrombectomy treatment, the design may be adapted for other procedures and other body passages as well.

[0041] Exemplary catheters disclosed herein can include spine reinforcements. In general, catheters with spine reinforcements can be of many different types. The methods described herein can be applied to many different types of catheters (e.g., funnel catheters or tubular suction catheters). The distal end portion of the catheter can be of various shapes and sizes and can have several configurations.

[0042] The flexibility of the catheter allows a physician to quickly create a pathway to the vicinity of the occlusion and gain access using a smaller diameter standard sheath or outer access catheter (not shown). Exemplary catheters disclosed herein may include an expandable tip. The expandable tip of the exemplary catheter may be collapsed by pushing the tip into a guide catheter with the support of a tubular loading tool. The tip may then be expanded as it exits the guide catheter a distance from the thrombus. The tip may then be advanced toward the thrombus location. Alternatively, the expandable tip may be expanded at the treatment location so that the expanded tip does not need to be advanced through the vasculature, thereby allowing for a relatively short length of the elongate shaft.

[0043] Some exemplary catheters disclosed herein can have an expanded, deployed configuration of the tip section 210 at the distal end 214 of the thrombectomy catheter, which can be flared or funnel-shaped. By incorporating a funnel shape into the expandable tip, the thrombus can be gradually compressed to a smaller diameter during retrieval, allowing it to be completely aspirated through the catheter and into an aspiration syringe or canister. This compression reduces the likelihood that a firm, fibrin-rich thrombus will become lodged in the tubular portion of the thrombectomy catheter. If a thrombus does become lodged in the tip port, the expanded port protects the thrombus and prevents it from being dislodged as suction is maintained and the catheter is retracted into the sheath or outer catheter.

[0044] The funnel-shaped design of the expandable tip of the disclosed embodiments can be an integrated lattice laser-cut directly and integrally with the elongated shaft of the catheter shaft. Alternatively, the expandable tip lattice can be injection molded as a single piece and attached to the elongated shaft by heat welding, adhesive, or similar means. The distal portion of a thrombectomy catheter can be designed to expand to a wide range of target vessel diameters, such as the distal carotid artery (3.2-5.2 mm), the horizontal MI portion of the middle cerebral artery (1.6-3.5 mm), and / or the internal carotid artery (ICA, 2.7-7.5 mm). Some exemplary catheters can be configured so that if the catheter is subsequently retracted from the MI portion to the ICA (or through another pathway with a proximally increasing vessel inner diameter), the expandable tip is likely to continue sealing the vessel over a range of vessel diameters. Furthermore, a tip capable of adopting a range of target vessel diameters can also seal vessel bifurcations, which may have a wider cross-sectional area than the vessels proximal and distal to the bifurcation. The distal portion of the catheter may be expanded prior to reaching the treatment location or at the treatment location to avoid the need to advance the expanded tip through the vasculature.

[0045] In some exemplary catheters disclosed herein, the distal portion of the aspiration thrombectomy catheter has good thrust and trackability characteristics to aid in advancing it to the target location. Therefore, the catheter can have multiple designs or be made from multiple materials to provide a decreasing stiffness profile along its length to minimize insertion and retraction forces. In one example, the elongate shaft can be laser cut from hypotube and integrally formed with the extended frame portion of the tip section. In another example, the elongate shaft can be an injection-molded polymer or metal braided or woven support structure. It can also incorporate forming elements that bias bending or encourage twisting about a specific plane to reduce applied strain. This allows the catheter to maintain excellent lateral flexibility but not tend to expand or kink in a compressed state.

[0046] Exemplary catheters can also have a cover or membrane disposed around or enclosing the elongate shaft and tip section. In the disclosed embodiments shown in the figures herein, the jacket or membrane is often not shown to allow for clarity of the underlying support structure, but the structure and appearance of such a membrane would be recognizable to one skilled in the art. Suitable membrane materials can include elastomeric polyurethanes, such as ChronoPrene®, which can have a Shore hardness of 40A or less (e.g., using the ASTM D2240 A scale), or silicone elastomers. The tip section may include elastomeric polyurethanes with a percentage of silicone, such as Neusoft 42A, 52A, 62A, or 72A. Other suitable materials may include ReZalloy 40A, 50A, 60A, or 70A, Rezithane 60A or 70A, or Engage 50A. The shaft may include a distal soft segment and a more proximal stiff segment, which may comprise a non-elastomeric material such as Pebax 25D, 35D, 45D, 55D, 63D, 72D, or 74D, or Rilasmid Nylon 12 or Rilasmid ML21. A single or variable stiffness cover may also be extruded or post-formed onto the elongate shaft. The cover may also be laminated or heat welded to the structure.

[0047] Alternatively, the cover can be formed from a series of polymer jackets. Different jackets or sets of jackets can be arranged at discrete lengths along the axis of the elongate shaft to provide different pushability and flexibility characteristics to different portions of the catheter tubular section. By configuring the jackets in an axial array, the overall stiffness of the catheter can be transitioned from a stiffer proximal end to a very flexible distal end. Alternatively, the polymer jackets of the cover can be arranged in a radial array around the elongate shaft to tailor the material properties across the thickness. In further embodiments, the transitions between jackets can be tapered or slotted to provide a smoother transition between the flexibility profiles of adjacent jackets in the longitudinal array.

[0048] To facilitate smooth delivery of the thrombectomy catheter through the outer catheter, the outer surface of the membrane or outer jacket can be coated with a low-friction material, such as PTFE or FEP, or a lubricious material, such as those offered by BioCoat, Surmodics, Harland, Covalon, or other companies. In another example, a low-friction inner liner can be applied to the inner circumference of the elongate shaft. Alternatively, a coating, such as a lubricant (such as silicone oil or molybdenum disulfide) or a hydrophilic coating, can be used. In a further example, if formed from a polymer extrusion, the inner or outer surface of the membrane, or the tubular portion of the catheter body, can be impregnated with a low-friction component that migrates to the surface, thereby eliminating the need for a low-friction liner.

[0049] The elongate shaft structure of the thrombectomy catheter may have many different configurations and may include different spine configurations. The spine may be tubular or wire-shaped to provide high axial stiffness for advancing and retracting the catheter with sufficient lateral flexibility to track through a blood vessel. The use of multiple spines promotes bending along a defined plane while reducing the likelihood of the elongate shaft stretching under tensile loads, such as when the expandable tip is retracted into the port of the outer catheter.

[0050] The spine can be made from a variety of materials, including metal or polymer. Metal spines can be interwoven during the manufacturing of the braid (commonly made from Nitinol) and can withstand the heat-setting temperatures of the frame. Interwoven spines allow the spine to maintain its position during use when the product is bent. The spine is locked into the braid and cannot be pulled through the liner (compared to being placed between the liner and braid) or jacket (compared to being placed between the jacket and braid). A liner with a strike layer can be beneficial when placing the spine between the liner and braid. PTFE liners do not melt during reflow, so the spine can prevent the outer jacket from bonding to the liner. If a strike layer (e.g., a thin 0.00025-inch layer of Pebax 55D) is used, this strike layer also melts with the outer jacket, allowing for better adhesion under the spine. Interwoven spines can also facilitate assembly, as the spine has a stable position. The metal spine can be made from, by way of non-limiting example, nitinol, stainless steel, cobalt-chromium, titanium alloy, tungsten, or drawn filled tube (DFT®) wire. A tungsten spine offers the added advantage of being radiopaque. The metal spine can comprise a shape memory alloy. The spine may extend the entire axial length of the catheter or may extend only a portion of the catheter's length. Preferably, the spine extends the majority of the catheter's length. The spine may have a non-circular cross-section and may have portions of different thicknesses.

[0051] Polymer or fiber spines can also be used. Polymer spines can be interwoven. If the braid requires heat curing, metal spines may be advantageous over polymer spines because polymer spines can be damaged at heat curing temperatures. Polymer spines can melt and reflow to form an excellent bond with the jacket and braid. Polymer splines can be made from, but are not limited to, high-density polyethylene, polyetherketone, ultra-high molecular weight polyethylene, aromatic polyamide, LCP liquid crystal polymer, nylon, or thermosetting liquid crystal polyoxazole. Polymer spines can be laminated or coextruded with the outer jacket. Fiber spines can be placed under or on top of the braid, but do not melt / flow into the braid during reflow.

[0052] Referring to FIG. 1, catheter 100 is a thrombectomy catheter for use in retrieving thrombi or occlusions from a patient's blood vessel. Catheter 100 includes an elongate shaft 110. The elongate shaft 110 is disposed along a longitudinal axis 111. The elongate shaft 110 includes an inner liner 115 and a shaft braid 120. At the proximal end (toward the right side of the drawing), the shaft braid 120 wraps around the inner liner 115. At the distal end (toward the left side of the drawing), a distal tip section 210 can be sized and configured to radially expand upon deployment at a target site to atraumatically contact the inner vessel wall, restrict / stop blood flow to prevent unwanted aspiration of blood near the tip, and provide a large opening for aspirating and receiving thrombi.

[0053] In the distal tip section 210, the shaft braid 120 expands to become the tip braid 220 and terminates in a distal hoop 230. The tip braid 220 may have portions made from a different material than the shaft braid 120. The intersections of the braids form cells 226. At the distal end of the tip section 214, a braid inversion 238 occurs, and the distal hoop 230 forms the distal-most cell 228. A spine 130 extends between layers of the shaft braid along the longitudinal axis 111. The spine 130 is preferably metal or polymeric. The spine 130 may be positioned at an intersection of the shaft braid 120. Both strands of the spine 130 may be interwoven with the shaft braid 120, or the spine may have one strand interwoven with the shaft braid 120 and another strand placed on top of the shaft braid 120. This may be created by transitioning one of the braid loops into a double spine in the shaft section. Alternatively, both strands can be positioned below or above the shaft braid. Furthermore, one strand may be interwoven, while the other strand may be positioned above or below the braid. The spine 130 includes a proximal portion 143 and a distal portion 144, which are separated by a transition point 135. The transition point 135 need not occur at the beginning of the inner liner 115. The transition point 135 may be closer to the proximal end of the catheter, which may create a more flexible portion of the shaft between the tip and the spine 130. The distal portion 144 of the spine forms a spine hoop 231. The spine hoop 231 may be positioned between the distal hoops 230 of the tip braid 220, such that the spine hoop 231 adds a hoop to the tip braid.

[0054] FIG. 2 is similar to FIG. 1 except that the spine hoop 231 is positioned adjacent to the distal hoop 230 of the tip braid and reinforces one of the distal hoops 230 rather than adding an additional hoop to the tip braid. Referring to FIG. 2, the spine 130 has a proximal portion 143 and a distal portion 144. The two strands of the spine are separated at a transition point 135. The spine distal portion 144 may be interwoven with the shaft braid 120 such that the spine hoop 231 wraps around the distal hoop 230 of the tip braid 220. This may be created by adding an additional braid loop alongside one of the existing loops.

[0055] FIG. 3 illustrates the positioning of a spine 130 within the shaft braid 120 of the catheter of FIG. 2. The spine may have two or more adjacent parallel strands (131, 132). The proximal portion of the spine 143 extends longitudinally and includes an axial first strand 131 and an axial second strand 132. The axial first strand 131 is positioned horizontally next to the axial second strand 132, e.g., at a similar radius from the longitudinal axis 111 (not shown), but may be positioned in a different configuration. The woven strand 134 overlying the shaft braid 120 extends above the spine 130. The underlying woven strand 133 extends below the spine 130. The spine 130 may be positioned near the intersection of the woven strands 133, 134.

[0056] Figure 4 shows a cross-sectional view of the elongate shaft 110 including the spine 130 of the catheter of Figure 2. The interior of the catheter is referred to as the inner lumen 116. An inner liner 115 surrounds the inner lumen and underlying the shaft braid 120. The shaft braid 120 includes underlying woven strands that underlie the axial first strands 131 and the axial second strands 132 of the spine 130. An overlying woven strand 134 overlies the axial first strands 131 and the axial second strands 132. An outer jacket 180 surrounds the overlying woven strands 134.

[0057] FIG. 5 is similar to FIG. 2, except that the spine hoop 231 shown in FIG. 2 is replaced by a spine loop 229 that bends approximately 360 degrees near the distal end of the elongate shaft 110 and does not extend into the distal tip section 210. Referring to FIG. 5, the spine 130 creates the spine loop 229 around the shaft braid and extends only throughout the proximal section of the catheter 100. The strands of the spine 130 may be interwoven through the shaft section. Alternatively, one strand may be interwoven and the other may be looped back onto the braid. The loop may extend around one or more of the braid wires. As shown, the loop 229 is positioned at the intersection of two braid wires of the shaft braid 120. Alternatively, the spine loop may be free-floating and not loop around any of the braided structures. In some embodiments, tension on the proximal elongate shaft 110 may cause the loop 229 to engage the braided wires of the shaft braid 120 at the crossover point, preventing elongation of the proximal elongate shaft 110. This embodiment may also be used in some cases with fiber strands for the spine 130. The spine may extend the entire length of the elongate shaft 110 or a partial length. The two formed strands 131, 132 may be parallel, and one of the parallel strands may be internal to the shaft braid 120. Additionally, one of the parallel strands may be external to the shaft braid 120. The loop 229 may be located in various positions on the shaft braid 120.

[0058] Figure 6 shows a cross section of the shaft 110 illustrating the positioning of the spine 130 of Figure 5. The inner lumen 116 is contained by an inner liner 115. The axial second strands 132 are positioned below the shaft braid 120. The axial first strands 131 are positioned above the shaft braid 120. An outer jacket 180 surrounds the shaft braid 120 and the axial second strands 132. The axial first strands 131 and the axial second strands 132 may be positioned to be perpendicularly aligned at localities (e.g., crossover points) within the shaft braid where the braid diameter is minimized.

[0059] FIG. 7 illustrates an additional configuration of a catheter with spine reinforcement. FIG. 7 shows a catheter with a first spine 136 having an axial first strand 131 and an axial second strand 132 that form a spine loop 229. The spine loop 229 is positioned where the proximal shaft 110 transitions to the distal tip section 210. FIG. 7 also includes a second spine 138 positioned 180 degrees from the first spine 136. The second spine 138 extends just beyond the distal end 119 of the inner liner 115 such that the spine loop 229 of the second spine 138 is positioned proximate the distal end 119 of the inner liner 115. One, two, three, or more spines may be applied above, below, or interwoven with the braid. The spines may be spaced 180 degrees apart. The addition of two spines prevents the support tube from stretching under tensile load and imparts a preferred bending plane to the tube. When aligned parallel to the longitudinal axis, the twin spines, spaced 180 degrees apart, change the tube's preferred bending location, allowing the support tube to self-adjust as it advances through tortuous vessels.

[0060] FIG. 8 is similar to FIG. 5, except that the spine 130 has only a single strand. The spine 130 is positioned below the shaft braid 120 and above the inner liner 115. The spine 130 includes only a single strand that terminates at a termination point 141. The termination point 141 may be located at an intersection of the shaft braid. The termination point 141 may be located proximally relative to the distal end 119 of the inner liner 115. Alternatively, the single strand may be interwoven. The distal end of the spine may be welded to one or the axial set of braid wires. The distal end may also be tied around one of the braid wires. Alternatively, brazing or adhesive may be used to hold the distal end of the spine relative to the braid wire. Either of these fastening methods prevents the strand from penetrating the outer jacket.

[0061] Figure 9 shows an additional configuration of a catheter with spine reinforcement. Figure 9 includes a self-expanding collapsible superbore (CSB) tip 310 with an expanded inner diameter 215. A spine loop 229 extends through the central portion of the body. The spine loop 229 may extend partway along the funnel taper or at the beginning of the funnel taper. The collapsible superbore catheter may also be capable of including an inner catheter with a low shear tip (LST).

[0062] FIG. 10 illustrates an additional configuration of a catheter with spine reinforcement. It includes a thrombus-expanded LST tip 311 having an inner diameter 217. The spine 130 extends the majority of the liner distance 145. The spine 130 is a single strand at the proximal end of the catheter and has a termination point 141 that forms a loop 229. The spine loop 229 has an inverted length 142 that extends along the length of the liner. The spine loop 229 travels from below the shaft braid up around the top of the shaft braid and reconnects at termination point 141. The spine loop 229 may transition from below the shaft braid to above the shaft braid distal to the intersection of two distal hoops 230. This positioning may be advantageous to prevent the LST tip from stretching. The spine loop 229 may optionally not reconnect to the lower strand at termination point 141.

[0063] FIG. 11 shows a lamination (or reflow) manufacturing method, which can be used to add a polymer spine during the lamination process with minimal impact on flexibility. The polymer spine 130 may have a higher harness than the soft outer jacket 180. The inner liner 115 is located inside the shaft braid 120. The spine 130 rests on top of the shaft braid 120 inside the outer jacket 180. When heated, the outer jacket 180 melts to the shaft braid along with the spine 130. This reflow through the braid allows the braid to bond with the liner, which may be made from PTFE. The spine may be made from Pebax® 40D-90D or another material and may be used to increase the force at which tensile elongation occurs relative to the soft outer jacket 180 (which may be made from, for example, Neusoft® 42A, 52A, 62A, 72A, Chronoprene® 20A-80A, ReZalloy 40A-80A, or ReZithane 40A-80A). It may be advantageous for the spine to have a low elongation relative to the elastomeric outer jacket 180. The polymer spine should have a melting temperature similar to that of the polymer jacket to improve bonding. The melting temperature of the spine material may differ from the melting temperature of the jacket material by ±40 degrees Celsius, ±17 degrees Celsius, ±10 degrees Celsius, or ±6 degrees Celsius. Ideally, if multiple jackets are used, the melting temperature of the spine most closely matches the melting temperature of the soft jacket that will benefit most from the tensile strength of the spine. For example, nylon would be a good spine material for the Neusoft® 42A jacket because they have similar melting temperatures. Nylon also has higher harness and tensile strength than Neusoft® 42A, making this a favorable combination.

[0064] FIG. 12 illustrates a coextrusion manufacturing method that can be used to add a polymer spine. The spine 130 is coextruded into a soft outer jacket 180. The shaft braid 120 and inner liner 115 are inserted inside the outer jacket 180 and spine 130. A reflow is then performed on the braid and liner to bond the outer jacket 180 and splines 130 to the shaft braid 120 and inner liner 115. The spine may be made from Pebax® 60D-90D or another elastomer and may be used to increase the force at which tensile elongation occurs relative to the soft outer jacket 180 (which may be made, for example, from Neusoft® 42A, 62A, 72A, or Chronoprene® 20A-80A). This has minimal impact on flexibility.

[0065] 13A-13I show the construction of a catheter having a funnel tip 322. As shown in FIG. 13A, construction of this catheter can include fitting a spine 317 and an inner liner 315 to a braided member 320 using an application mandrel 350. The application mandrel 350 includes the inner liner 315 on the application mandrel 350. The spine 317 is positioned on the inner liner 315. At the inner liner distal end 319, a distal marker band 321 is positioned on the inner liner 315 and the spine 317.

[0066] In FIG. 13B, the application mandrel 350, spine 317, inner liner 315, and distal marker band 321 are positioned inside the braided member 320. FIGS. 13C and 13D show subsequent construction steps for two different spine 130 configurations. FIG. 13C shows the spine 317 folded back to form a spine loop 329 similar to that shown in FIG. 5. FIG. 13D shows the spine 317 having a proximal portion 343 and a distal portion 344 separated by a transition point 335, forming a spine hoop 331 similar to that shown in FIG. 2. Alternatively, in the step shown in FIGS. 13C and 13D, the spine 317 can be shaped as disclosed elsewhere herein or otherwise shaped as would be understood by one of ordinary skill in the art following the teachings herein. In this step, an outer body jacket 382 is added. In this step, funnel tip 322 is created by forming braided member 320 into distal hoop 330 .

[0067] FIG. 13E shows a reflow tool for a funnel tip catheter. This catheter may have a CSB tip. The reflow tool 352 includes a distal inner jacket 384. In FIG. 13F, the reflow tool 352 is inserted into the catheter, which is shown with a spine hoop 331 but may also have a spine loop. The distal inner jacket 384 is inserted inside the distal hoop 330, down the length of the funnel tip 322, up to the inner liner 315, in the direction of arrow 390. In FIG. 13G, the reflow tool 352 is heated, bonding the distal inner jacket 384 to the distal hoop 330. A distal outer jacket 385 is also placed over the distal end of the catheter. The reflow tool 352 can then be removed in the direction of arrow 392 (shown in FIG. 13H). FIG. 13I is a side view of the completed catheter with an orifice 349.

[0068] 14A and 14B show a method 14000 for constructing a catheter with spine reinforcement. In step 14010, an inner liner is placed around an application mandrel. The mandrel can be used to provide structure during manufacturing and define what may be the inner lumen of the catheter. By way of example, a nominal 6 Fr size catheter shaft may use an application mandrel having an outer diameter of approximately 0.071 inches, and the inner liner may be approximately 0.005 inches thick. The mandrel may be silver-plated copper (SPC) or other commonly used material and may be sized to have an outer diameter such that the resulting catheter has a larger diameter (at least 0.070 inches) than many modern aspiration catheters. The liner may be etched PTFE or a similar low-friction material. A strike layer may also be included to better adhere the inner liner to subsequent layers of the catheter shaft.

[0069] In step 14020, one or more axial spines are positioned parallel to the longitudinal axis outside the outer surface of the inner liner. In optional step 14030, the polymer used for at least a portion of the one or more spines has a melting temperature within ±17°C of the melting temperature of the distal-most outer jacket of the catheter. The polymer spine may have a melting temperature similar to that of the polymer jacket to improve bonding. Ideally, if multiple jackets are used, the melting temperature of the spine most closely matches the melting temperature of the softer jacket that will benefit most from the tensile strength of the spine. In optional step 14040, the polymer used for at least a portion of the one or more splines has a melting temperature within ±6°C of the melting temperature of the distal-most outer jacket of the catheter. For spines that do not melt or only partially melt, looping the distal end can be advantageous because it attaches the spine to the braid and prevents the spine from slipping if the tip end is pulled away from the proximal portion of the shaft. This added benefit of looping the distal end may not be present or necessary in a fully fused spine.

[0070] In step 14050, a braided member is placed around at least a portion of the inner liner on an application mandrel. The braided member has a proximal portion and a distal portion. The distal portion terminates in a distal hoop pole. This braided member can be the reinforcing structure for the majority of the catheter shaft. This pattern can utilize 16 wires in a 1 wire-over-1 / 2 diamond pattern for the distal section, as this pattern is balanced during tip expansion. Alternative patterns can include two 1 wire-over-2 herringbone patterns for increased column stiffness and kink resistance. Other patterns can be contemplated for various catheter design requirements (e.g., a full diamond pattern). In optional step 14060, at least one of the one or more spines that loop through the opening in the braided member is inverted. In optional step 14070, a distal portion of one or more of the axial spines is inverted to form one or more distal hoops of the tip section braid.

[0071] In step 14080, a series of outer jackets are reflowed to bond the catheter assembly. The jackets may preferably be axially in series, although some combination of axial and radial series may be used. The flow of the jacket materials may allow them to encapsulate the braid of the elongate body and bond with the inner liner. In optional step 14090, at least a portion of one or more spines are laminated with the outer jacket. In optional step 14100, at least a portion of one or more spines are co-extruded into at least a portion of the outer jacket to form a layered structure.

[0072] In step 14110, a polymer distal inner jacket is loaded around the reflow tool. The supporting braid frame of the distal tip section braid can allow for the use of very soft jacket materials, such as Neusoft, with a hardness of 40A to 80A, for atraumatic properties. The inner jacket can be thin (e.g., approximately 0.001 to 0.004 inches), which can be used to achieve a more uniform wall thickness around the tip section and ensure complete encapsulation of the braid so that the lumen is smooth and unobstructed. In optional step 14120, a reflow tool with a flared distal end is utilized. In step 14130, the application mandrel is removed, and the reflow tool with the polymer distal inner jacket is inserted into the distal end of the catheter assembly. The inner jacket may contain a low-friction filler, such as Mobilise or Propell, to facilitate removal from the reflow tool and to provide low friction at the ID for smooth passage of assist devices or more efficient retraction of thrombus.

[0073] In step 14140, a polymeric distal outer jacket is positioned around at least the distal portion of the catheter assembly on a reflow tool. Similar to the distal inner jacket, the distal outer jacket can be a thin Neusoft layer that can be laminated or reflowed to fuse with the inner jacket so that the final wall thickness of the combined distal polymeric jacket is approximately 0.004 to 0.010 inches, maintaining at least 0.0005 inches of jacket material above and below the braid surface. The jacket can extend proximally to the distal edge of the proximal outer jacket of the elongate body and protrude distally at least several millimeters beyond the distal end of the braid hoop of the distal tip braid. In step 14150, the polymeric distal inner jacket and polymeric distal outer jacket are reflowed onto the distal portion of the catheter assembly. In step 14160, the reflow tool is removed.

[0074] In optional step 14170, an inner hydrophilic coating is applied to at least the interior of the distal portion of the catheter assembly. A process such as dip coating can be used to apply the coating to both the interior and exterior surfaces after removal of the flared mandrel. In most cases, the coating can cover at least the most distal 20 cm of the catheter. In some cases, the hydrophilic coating can also be applied to the interior surface of the tip, where there is no PTFE liner. Further post-processing, such as reflow and compression / injection molding steps, can also be used to apply additional material or flow existing material to add features to the expandable tip. Features can be, for example, feathered edges, disk extensions, polymer lips, or axial ribs.

[0075] Referring to FIG. 15A, the catheter 400 includes an elongate body 410, a spine 412, a distal outer jacket 430, and a distal inner jacket 434. The spine 412 has a flat spine end 414 that extends beyond the inner liner 411. The spine 412 is placed under the braid 413 and above the inner liner 411. Alternatively, one end of the spine may be tied to the braid wire to create a distal fixation point. The inner liner 411 may be made of polytetrafluoroethylene (PTFE). The spine material should have sufficient strength to reduce shaft elongation. The spine material may have a strength greater than 5 N. The spine material may have a strength greater than 15 N. The spine may be metal or polymer, or may be a multifilament polymer.

[0076] FIG. 15B is similar to FIG. 15A. However, the spine 412 has lasso spine ends 416 that extend outward to the distal outer jacket 430. The spine 412 rests beneath the braid 413 and over the inner liner 411 with distal loops 416. The distal loops 416 are pulled through the braid opening and around the outer diameter of the braid. Alternatively, the distal loops 416 of the spine 412 can be tied to the braid wire using a lasso knot (shown in FIG. 16). The lasso spine ends may be tied to the braid 413 at the braid crossover points 420. Attaching the spine to the braid with a knot or lasso prevents the braid from stretching and overpowering the adhesive forces between the polymer jacket and the spine.

[0077] FIG. 17A is similar to FIG. 15A. In FIG. 17A, a small amount of adhesive 440 is used to secure the distal end of the spine to the braid and liner. FIG. 17B is similar to FIG. 15A. In FIG. 17B, a short length of harder outer jacket polymer 450 is used to secure the distal end of the spine to the braid and liner. FIG. 17C is similar to FIG. 15A. In FIG. 17C, a marker band 460 is placed over the braid and spine 412. The marker band 460 may be crimped to secure the spine 412 to the braid, spine, and marker band together. Alternatively, adhesive may be applied under the marker band 460 to secure the braid, spine, and marker band together.

[0078] FIG. 18 is a side view of a catheter having a spine reinforcement 312 similar to that shown in FIGS. 17A and 17B, where a marker band 460 is used to attach the spine, and the marker band 460 is on top of the braid.

[0079] Any of the support tubes for the thrombectomy catheter designs disclosed herein can be used with a mechanical thrombectomy device. Combining mechanical thrombectomy with aspiration through the funnel-shaped tip can increase the chances of first-pass success in thrombus removal. During thrombectomy, the funnel-shaped tip reduces shearing of the thrombus as it enters the catheter, halting flow and protecting the distal vessel from embolization of new areas. Furthermore, the mechanical thrombectomy device can direct aspiration vacuum to the thrombus surface while holding the composite thrombus (consisting of fragile and fibrin-rich regions) together, thereby preventing embolization and helping to slough the thrombus away from the vessel wall. The tip shape can also help prevent fragmentation if the thrombus enters an offset position at the catheter port.

[0080] The mechanical thrombectomy device can be configured to support the lumen of the blood vessel during aspiration to resist collapse under negative pressure, holding the thrombus together when the thrombus contains many hard and soft segments that could fragment. The mechanical thrombectomy device also allows the user to pinch any thrombus that does not fit completely into the lumen of the thrombectomy catheter, thereby preventing the thrombus from falling out of the thrombectomy catheter as the thrombectomy catheter, thrombus, and mechanical thrombectomy device are pulled together through the vasculature, through the outer catheter, and out of the patient. The interaction of the outer catheter with the enlarged port can help gradually compress the thrombus so that it can be pulled through the outer catheter along with the thrombectomy catheter and mechanical thrombectomy device. If the thrombus is still too large to fit into the outer catheter, the thrombectomy catheter and mechanical thrombectomy device can be retracted proximally through the blood vessel into a second, larger-diameter outer catheter, such as a balloon guide. If the thrombus is still too hard to retrieve through the second outer catheter, the entire device can be retracted together through the vasculature and out of the body as a unit. The thrombectomy catheter may be designed to be advanced through an outer catheter, such as a 7Fr, 8Fr, 9Fr, or 10Fr guide catheter or balloon guide catheter. Alternatively, the thrombectomy catheter may be designed as a 4Fr, 5Fr, or 6Fr midcatheter. In another embodiment, a funnel feature may also be provided on a 7Fr, 8Fr, 9Fr, or 10Fr guide sheath to provide a seal within a larger vessel instead of a balloon guide sheath.

[0081] The descriptions contained herein are examples of embodiments of the present invention and are not intended to limit the scope of the present invention in any way. As described herein, the present invention contemplates many variations and modifications of catheters, including funnel catheters and tubular suction catheters. Modifications and modifications obvious to those skilled in the art from the teachings of the present disclosure are intended to be within the scope of the following claims.

[0082] [Embodiment] (1) A catheter, a proximal elongate shaft including a longitudinal axis, a distal end, and a shaft braid; a distal tip portion comprising a tip braid terminating in a distal hoop; a plurality of outer jackets disposed around the elongate shaft and the tip portion; one or more metallic spines extending at least partially along the axial length of the catheter, the one or more metallic spines inhibiting tensile elongation of the catheter; A catheter wherein the distal hoop of the tip braid is integrally formed with the wires of the shaft braid. (2) A catheter as described in embodiment 1, wherein at least a portion of the one or more metal spines comprises a shape memory alloy. (3) A catheter as described in embodiment 1, wherein at least a portion of the one or more metal spines comprises at least one of stainless steel, DFT, cobalt chromium, titanium alloy, or tungsten. (4) A catheter as described in embodiment 1, wherein at least one of the one or more metal spines is interwoven with the shaft braid. (5) A catheter as described in embodiment 1, wherein at least one of the one or more metal spines has a proximal portion and a distal portion, and at least a portion of the proximal portion has two or more adjacent parallel strands.

[0083] (6) A catheter as described in embodiment 5, wherein the distal portion forms one or more of the distal hoops of the tip portion braid. (7) A catheter as described in embodiment 1, wherein at least a portion of the one or more metal spines extend throughout the entire axial length of the catheter and have a non-circular cross-section. (8) A catheter as described in embodiment 1, wherein the one or more metal spines further include a first spine and a second spine spaced 180 degrees apart. (9) A catheter as described in embodiment 1, wherein at least one of the one or more metal spines has a portion of different thickness, and the one or more metal spines are external to the shaft braid. (10) A catheter as described in embodiment 1, wherein the one or more metal spines further comprise a single spine attached to one of the shaft braid or the tip braid at an end point.

[0084] (11) A catheter, an elongate tube having a longitudinal axis and a shaft braid comprising the first set of helical wires braided with the second set of helical wires; a distal tip portion comprising a tip braid having a distal hoop at its distal end; a plurality of outer jackets disposed around the elongated tube and the tip section; one or more polymer spines extending at least partially along an axial length of the catheter, the one or more polymer spines inhibiting tensile elongation of the catheter; the first set of helical wires of the shaft braid are reversed proximally to form the second set of helical wires of the shaft braid; A catheter wherein the distal hoop of the tip braid is integrally formed with the wires of the shaft braid. (12) The catheter of embodiment 11, wherein at least a portion of the one or more polymer spines comprises at least one composition of high density polyethylene, polyetherketone, ultra-high molecular weight polyethylene, aromatic polyamide, LCP liquid crystal polymer, nylon, or thermoset liquid crystal polyoxazole. (13) The catheter of embodiment 11, wherein at least a portion of the one or more polymer spines is laminated with the outer jacket. (14) The catheter of embodiment 11, wherein at least a portion of the one or more polymer spines is coextruded with at least one of the outer jackets. (15) A catheter as described in embodiment 11, wherein at least one of the one or more polymer spines is interwoven with the shaft braid.

[0085] (16) A catheter as described in embodiment 11, wherein at least one of the one or more polymer spines is inverted through the shaft braid or the tip braid at a spine loop to form two parallel strands. (17) At least a portion of one of the parallel strands extends outside the shaft braid; A catheter as described in embodiment 16, wherein at least a portion of one of the parallel strands extends within the shaft braid. (18) A method for constructing a catheter, comprising: placing an inner liner around an application mandrel; positioning one or more axial spines on an exterior surface of the inner liner substantially parallel to the longitudinal axis; placing a braided member around at least a portion of the inner liner on the application mandrel to form a catheter assembly, the braided member comprising a proximal portion and a distal portion terminating in a plurality of distal hoops; reflowing a series of proximal outer jackets to bond the catheter assembly; loading a polymeric distal inner jacket around the reflow tool; removing the application mandrel and inserting the reflow tool and the polymeric distal inner jacket into the distal end of the catheter assembly; positioning a polymeric distal outer jacket around at least the distal portion of the catheter assembly on the reflow tool; reflowing the polymeric inner and outer distal jackets onto the distal portion of the catheter assembly; and removing the reflow tool. (19) The method of embodiment 18, further comprising utilizing a polymer in at least a portion of the one or more spines having a melting temperature within approximately ±17 degrees of the melting temperature of the distal-most outer jacket of the catheter. (20) inverting at least one of the one or more spines to loop through an opening in the braided member; inverting a distal portion of one or more of the axial spines to form one or more of the distal hoops of a tip portion braid; laminating at least a portion of the one or more spines with the outer jacket; co-extruding at least a portion of the one or more spines into at least a portion of the outer jacket to form a layered structure; utilizing a reflow tool having a flared distal tip; 20. The method of claim 19, further comprising applying an inner hydrophilic coating to at least the interior of the distal portion of the catheter assembly.

Claims

1. A catheter comprising: a proximal elongate shaft including a longitudinal axis, a distal end, and a shaft braid; a distal tip portion comprising a tip braid terminating in a distal hoop; a plurality of outer jackets disposed around the elongate shaft and the tip portion; one or more metallic spines extending at least partially along the axial length of the catheter, the one or more metallic spines inhibiting tensile elongation of the catheter; A catheter wherein the distal hoop of the tip braid is integrally formed with the wires of the shaft braid.

2. The catheter of claim 1 , wherein at least a portion of the one or more metallic spines comprises a shape memory alloy.

3. The catheter of claim 1 , wherein at least a portion of the one or more metal spines comprises at least one of stainless steel, DFT, cobalt chrome, titanium alloy, or tungsten.

4. The catheter of claim 1 , wherein at least one of the one or more metallic spines is interwoven with the shaft braid.

5. The catheter of claim 1 , wherein at least one of the one or more metallic spines comprises a proximal portion and a distal portion, and at least a portion of the proximal portion comprises two or more adjacent parallel strands.

6. The catheter of claim 5 , wherein the distal section forms one or more of the distal hoops of the tip section braid.

7. The catheter of claim 1 , wherein at least a portion of the one or more metallic spines extends the entire axial length of the catheter and comprises a non-circular cross-section.

8. The catheter of claim 1 , wherein the one or more metallic spines further comprise a first spine and a second spine spaced 180 degrees apart.

9. The catheter of claim 1 , wherein at least one of the one or more metallic spines comprises a portion of different thickness, and the one or more metallic spines are external to the shaft braid.

10. The catheter of claim 1 , wherein the one or more metallic spines further comprise a single spine attached to one of the shaft braid or the tip braid at a termination point.

11. A catheter comprising: an elongate tube having a longitudinal axis and a shaft braid comprising the first set of helical wires braided with the second set of helical wires; a distal tip portion comprising a tip braid having a distal hoop at its distal end; a plurality of outer jackets disposed around the elongated tube and the tip section; one or more polymer spines extending at least partially along an axial length of the catheter, the one or more polymer spines inhibiting tensile elongation of the catheter; the first set of helical wires of the shaft braid are reversed proximally to form the second set of helical wires of the shaft braid; A catheter wherein the distal hoop of the tip braid is integrally formed with the wires of the shaft braid.

12. 12. The catheter of claim 11, wherein at least a portion of the one or more polymer spines comprises at least one composition of high density polyethylene, polyetherketone, ultra-high molecular weight polyethylene, aromatic polyamide, LCP liquid crystal polymer, nylon, or thermoset liquid crystal polyoxazole.

13. The catheter of claim 11 , wherein at least a portion of the one or more polymer spines is laminated with the outer jacket.

14. The catheter of claim 11 , wherein at least a portion of the one or more polymer spines is co-extruded with at least one of the outer jackets.

15. The catheter of claim 11 , wherein at least one of the one or more polymer spines is interwoven with the shaft braid.

16. The catheter of claim 11 , wherein at least one of the one or more polymer spines is inverted through the shaft braid or the tip braid at a spine loop to form two parallel strands.

17. at least a portion of one of the parallel strands extends outside the shaft braid; The catheter of claim 16, wherein at least a portion of one of the parallel strands extends within the shaft braid.

18. 1. A method for constructing a catheter, comprising: placing an inner liner around an application mandrel; positioning one or more axial spines on an exterior surface of the innerliner substantially parallel to the longitudinal axis; placing a braided member around at least a portion of the inner liner on the application mandrel to form a catheter assembly, the braided member comprising a proximal portion and a distal portion terminating in a plurality of distal hoops; reflowing a series of proximal outer jackets to bond the catheter assembly; loading a polymeric distal inner jacket around the reflow tool; removing the application mandrel and inserting the reflow tool and the polymeric distal inner jacket into the distal end of the catheter assembly; positioning a polymeric distal outer jacket around at least the distal portion of the catheter assembly on the reflow tool; reflowing the polymeric inner and outer distal jackets onto the distal portion of the catheter assembly; and removing the reflow tool.

19. 20. The method of claim 18, further comprising utilizing a polymer in at least a portion of the one or more spines that has a melting temperature within approximately ±17 degrees of the melting temperature of the distal-most outer jacket of the catheter.

20. inverting at least one of the one or more spines to loop through an opening in the braided member; inverting a distal portion of one or more of the axial spines to form one or more of the distal hoops of a tip portion braid; laminating at least a portion of the one or more spines with the outer jacket; co-extruding at least a portion of the one or more spines into at least a portion of the outer jacket to form a layered structure; utilizing a reflow tool having a flared distal tip; 20. The method of claim 19, further comprising applying an inner hydrophilic coating to at least the interior of the distal portion of the catheter assembly.

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