HK40076269A - Catheter construction - Google Patents

Description

Conduit structure

Cross Reference to Related Applications

This application is a non-provisional application of U.S. provisional application 62/862,035 filed on 15.6.2019, the entire contents of which are incorporated by reference.

Technical Field

Polymeric tubing for catheters or other medical devices, wherein the polymeric tubing may have lengths with customized properties including, but not limited to, stiffness, torque control, flexibility, axial strength, rigidity, and the like. In one variation, the transition regions between lengths may be configured such that there may be abrupt, gradual, or customized transition regions between various lengths, thereby selectively tailoring the structural property differences between lengths and over the transition regions. In certain variations, differences in structural characteristics are minimized or eliminated as compared to conventional catheters.

Background

Medical catheters allow physicians to apply a variety of different treatments to a patient. Many catheters enter remote areas of the human body for delivering diagnostic or therapeutic tools and/or agents to these sites. Alternatively, the catheter may include a shaft or stent for the treatment working end (e.g., balloon, filter retriever, electrode, etc.). Some catheters, including but not limited to catheters for neurovascular use, are intended to pass from the aorta (e.g., femoral or radial arteries) through tortuous anatomy into small cerebral vessels. Thus, due to the diverse regions of anatomy through which the catheter passes, the catheter must be constructed to have diverse structural traits. Many times, the vascular path itself circuitizes into a multi-loop path, making it difficult for the catheter design to meet the requirements required for tortuous anatomy. For example, the catheter must be fairly stiff at its proximal end to be able to push and steer the catheter as it is advanced through the body, yet must be flexible enough at the distal end to allow the catheter tip to pass through loops and smaller vessels. In any event, the catheter does not cause significant trauma to the blood vessel or surrounding tissue.

Fig. 1A illustrates a generic catheter structure and shows a cross-sectional view of a catheter segment 10, which catheter segment 10 may be constructed on an internal mandrel or core 12 that is later removed. A common catheter structure includes a layer 14, such as Polytetrafluoroethylene (PTFE), which layer 14 provides a smooth surface for the interior of the catheter, while also supporting various structural components to provide the diverse sections 16 and 18 of the catheter 10. For example, the illustrated catheter 10 includes a reinforcement section 16 in which a braid or coil (coil)20 (or both) is wrapped around the second layer 14 in the reinforcement section 16. Many catheters use a metal braid at the proximal end of the catheter and a metal coil (or one under the other) at the distal end of the catheter. I is

Many catheters intended to navigate through tortuous anatomy also include regions 18 of varying stiffness in which regions 18 polymers 22, 24 and 26 of differing stiffness are placed adjacent to one another. Fig. 1A is intended to illustrate the basic structure of a conventional catheter. For illustrative purposes, the catheter 10 of fig. 1A shows the polymer 22 terminating prior to the distal end 8 of the catheter 10, with only the underlying stiffening segment 16 shown. In most conventional catheters, the entire distal end is encapsulated by the polymer.

As shown in fig. 1A, a wide variety of adjacently placed polymer sheaths 22, 24, 26 are placed over the reinforcement layer and fused into place (e.g., by heating and reflowing the polymer onto the braid or coil). Different polymer hardnesses (i.e., "stiffnesses") are used for the different sections, and thus each of these sections of the catheter will have unique structural properties/attributes, which may include, but are not limited to, stiffness, resistance to twisting or torsion, flexibility, fracture strength, and the like. The illustrated structure 10 provides varying structural characteristics over a diverse area of the catheter. However, in conventional devices, such a conduit structure produces abrupt changes in properties at the transition or edge of each region 22, 24, 26.

In many conventional catheter devices, a higher durometer polymer is used in the proximal region, and a softer durometer polymer is applied as the catheter progresses to the distal end. More sophisticated catheters have more "segments" or transitions in stiffness (i.e., smaller extrusions with different stiffness are used for the outer sheath). For example, FIG. 1C shows a schematic diagram manufactured by Microvention Termuo corporation (AlisoViejo, Calif.)A distal access catheter (a)Digital Access Catheter)19, which is an example of a commercially available intracranial Catheter described by Microvention having an "exceptionally soft Distal tip" and a "torqueable shaft" at a proximal length. The catheter includes an intermediate section 23 adjacent a soft distal tip 25. The proximal length of the catheter is not shown because fig. 1C is intended to show that the intermediate length 23 is made of a relatively higher durometer polymer and that there is an abrupt transition to the relatively softer distal tip 25. Typically, higher durometer polymers provide improved torque, rotational/axial stability, but are less flexible. As shown in FIG. 1C, a pushing force applied at the proximal end of a harder durometer polymer may cause region 38 to buckle, with region 38 being about where the polymer changes. Flexion results in poorer pushing and navigation.

Typically, a stiffer durometer is more suitable for the proximal region of the catheter. While the stiffer polymers do not bend well around turns, the stiffer polymers have better pose stability in the vessel and tend to transmit torque well. In contrast, a softer durometer is suitable for the distal region of the catheter; as these polymers bend more easily and softly around the more delicate and tortuous distal turns. However, the softer durometer polymer does not transmit torque well and has poor attitude stability. Thus, conventional catheter designs employ a "balancing act" between mechanical properties in which design elements (stiffness and stability, versus softness and less stability) are compromised. Furthermore, the change from one hardness to another has been a source of mechanical challenges. These transitions are a source of discontinuities and are known in the art to cause challenges to torque transfer and to cause irregularities in bending stresses that result in poor navigation through the anatomy. Thus, engineers try to make the transition as long and gradual as possible and mitigate abrupt changes by using a large number of small transitions instead of fewer large transitions.

Regardless of the length of the transition, the common configuration shown in fig. 1A relies on a braid or coil 20 (or both), which braid or coil 20 is used to transmit torque as the catheter travels through tortuous anatomy. However, due to the polymers 22, 24, 26 (etc.), a greater degree of torque is applied to the polymers outside of the braid/coil 20. Polymers with different physical properties will also have different torque resistance. For example, in variations where polymers 22, 24, and 26 have reduced flexibility (22 being the most flexible and 26 the least flexible), the torque applied by rotation of segment 26 will not be fully applied to segment 24. Thus, segment 24 does not rotate as much as segment 26. The segments 22 will produce the same effect; it does not rotate as much as segment 24 and less than segment 26. This results in poor torque control or torque instability. In addition, as these segments contract, the transition between the polymers can create discontinuities in the response of the catheter to the contraction and bending of the different segments.

Fig. 1B provides an illustration of a section of the catheter body 10 (without the abrupt transition region) that represents in a curved profile that the section of the catheter body 10 is pushed to progress through tortuous anatomy. Fig. 1B shows a force 7 applied to the proximal end 9 of the catheter body 10, which is resisted by the vessel wall, which resistance is denoted as force 6. To advance the catheter body 10, the force 7 must be greater than the force 6. When advancing through a tortuous path, the catheter body 10 is placed in tension 32 at the exterior of the curve and in compression 34 at the interior of the curve. However, polymers are suitable for compression or tension, and conventional catheter designs do not allow for the selection of a single polymer to maximize performance in both compression and tension. For example, a polymer that reacts well to stretching outside of a turn (e.g., a polymer that is generally softer) may not react well to compression inside of a turn. Also, polymers that react well to compression on the inside of a turn (e.g., relatively harder polymers) do not react well to tension on the outside of the turn. In addition, the polymer must also be selected to respond to torsional and axial compression. Otherwise, problems of poor or unstable torque control (e.g., known as "shudder") and axial instability (commonly referred to as catheter blockage) can result. As a compromise, common catheter designs require balancing polymer properties, but do not produce a device optimized for any given procedure. This compromise leads to undesirable effects. For example, fig. 1D provides an image of a react (tm)071 catheter 36 provided by Medtronic. The conduit 36 is held only at the end 37, allowing the conduit to assume its natural shape profile. As shown, the abrupt transition of the catheter 36 results in the bending radius being irregular at point 38, rather than having a smooth bending radius or turn, which causes the catheter to buckle as it is pushed. Flexion of the catheter 36 reduces the transmission of thrust forces to areas other than the flexion, and reduced traversability.

The undesirable abrupt transition region is only one of the disadvantages of conventional catheter designs that require a balancing act to compromise performance characteristics on any given section of the catheter by selecting less than ideal materials. Accordingly, there remains a need for improved catheter designs and catheter structures to produce catheters with highly customized properties.

Summary of The Invention

The catheter of the present invention allows for custom designed catheter structures without compromising performance characteristics. Such a catheter structure is possible by being able to customize the properties and materials of any given section of the catheter. Such customized properties include, but are not limited to, hardness, torque control, flexibility, axial strength, stiffness, and the like. The present disclosure also includes variations of the improved catheter having a graduated or customized transition section that may be selectively configurable. For example, any section of the polymeric conduit (and, thus, the finished catheter structure) may include a polymer having a low durometer, a medium durometer, and a high durometer in the same region. The ability to improve the transition is but one example of the benefits of an improved catheter constructed in accordance with the teachings herein.

To explain the features of the invention, polymer strands/components refer to the segments of material described herein prior to forming the tubular wall. As described herein, in some variations, the material segments may be formed from the first polymeric material and extend in a helical pattern. At some point, the first polymeric material terminates at one end and is joined to one end of the second polymeric material, which still extends or continues in the helical pattern of material segments. In this case, a material segment is considered to have two different polymeric materials in different longitudinal regions. In a further variation, the segments of material comprise polymeric material and extend helically over a longitudinal region of the pipe and then terminate such that adjacent segments of material are joined together to maintain continuity of the wall of the resulting pipe. It should also be noted that when referring to a single strand bonded structure, the terms tubular wall, polymeric pipe, polymeric layer, composite pipe, composite layer, and the like, may include material segments comprised of one or more of the following materials: metals, stainless steel, alloys, Liquid Crystal Polymers (LCP), fibers, composites, or other similar structures.

It should be noted that transition segments should be used to describe the alteration of one or more strands of material from a different material. The term transition region shall describe the overall effect of one or more transition segments. In some variations, the transition region does not include any transition sections that result from the material simply terminating. Thus, the catheter structure of the present disclosure may have a transition region that gradually changes material properties over the axial length, or, alternatively, the transition region may be a region of abrupt change in material properties.

The present disclosure includes variations of catheters having an outer conduit layer formed from a variety of materials to tailor the characteristics of the longitudinal region of the catheter. Certain variations of the catheter may also include such a composite polymer layer on an inner layer of the catheter structure, but in many variations, a custom composite layer is on an outer layer.

Variations of such catheter tubing may include a tubular outer layer extending along the axial length of the tubular body; the tubular body including a plurality of segments of material extending helically along an axial length to form a wall of the tubular body, wherein each segment of material is joined to an adjacent segment of material to form the wall; wherein the plurality of material segments includes at least a first material segment and a second material segment, the first material segment including a first structural attribute and the second material segment including a second structural attribute, wherein the first structural attribute is different from the second structural attribute; and wherein along the transition region of the tubular body the width of the first section of material increases and the width of the second section of material decreases, resulting in a change in the structural properties of the transition region along the transition region.

Another variation of a catheter may include an outer tubular body having a first section and a second section, each extending along an axial length of the tubular body; wherein the outer tubular body comprises a plurality of segments of material extending helically along an axial length, wherein each segment of material is sealingly joined to an adjacent segment of material to form a composite wall of the outer tubular body, the composite wall surrounding a lumen extending along the axial length; wherein in the first section, the plurality of sections of material includes at least a first section of material and a second section of material forming the composite wall, the first section of material including a first structural property and the second section of material including a second structural property, wherein the first structural property is different from the second structural property; and the third section of material has a third structural attribute, wherein the third section of material is joined to the end of the first section of material at the second section such that the third section of material replaces the first section of material in the second section.

Another variation of a catheter includes a catheter tube comprising: a tubular body having a first section and a second section, each of the first section and the second section extending along an axial length of the tubular body; and a plurality of segments of material extending helically along an axial length to form a first segment, wherein each segment of material is sealingly joined to an adjacent segment of material to form a composite wall of the tubular body that surrounds a lumen extending along the axial length; wherein each of the plurality of material segments comprises a structural property, respectively, and wherein the structural properties of at least two material segments are different; wherein the first segment comprises a first sequence of material segments and wherein the second segment comprises a second sequence of material segments such that the material segments in the first sequence are different from the material segments in the second sequence, resulting in a structural property of the first segment being different from a structural property of the second segment.

Another catheter structure includes the following catheter structure, the catheter structure comprising: a catheter shaft having an axial length, the catheter shaft including a tubular outer layer including a plurality of segments of material, each segment of material having a respective width measured along the axial length, the plurality of segments of material extending in a helical direction along the axial length to form a wall of the tubular outer layer, the tubular outer layer having a first longitudinal region, a second longitudinal region, and a transition region between the first longitudinal region and the second longitudinal region; wherein in the first longitudinal region, the plurality of material segments includes a first material segment and a second material segment, wherein a structural property of the first material segment is different from a structural property of the second material segment such that the first longitudinal region has a first structural characteristic; wherein at the transition region, the second section of material terminates at an end and a third section of material is joined to the end of the second section of material, wherein a structural property of the second section of material is different from a structural property of the third section of material; and wherein the first section of material and the third section of material extend helically from the transition region to the second longitudinal region such that the structural properties of the second longitudinal region are different from the structural properties of the second longitudinal region.

Yet another variation of the catheter structure includes a catheter shaft having a tubular outer layer extending over at least a portion of an axial length of the catheter structure, the tubular outer layer including a plurality of segments of material, each segment of material having a respective width measured along the axial length, the plurality of segments of material extending in a helical direction along the axial length to form a wall of the tubular outer layer, the tubular outer layer having a first longitudinal region, a second longitudinal region; and wherein, in the first longitudinal region, the plurality of material segments includes a first material segment located in the first longitudinal region having the first structural characteristic; wherein at least a portion of the first section of material terminates at an end in a second longitudinal region and the second section of material is joined to the end of the first section of material, wherein the structural properties of the first section of material are different than the structural properties of the second section of material such that the second longitudinal region has a second structural characteristic that is different than the first structural characteristic.

Another variation of the catheter structure includes a tubular outer layer including a plurality of segments of material, each segment of material having a respective width measured along an axial length, the plurality of segments of material extending in a helical direction along the axial length to form a continuous wall of the tubular outer layer; wherein the plurality of material segments includes a first material segment and a second material segment adjacent the first material segment, wherein a structural property of the first material segment is different than a structural property of the second material segment.

Another variation includes a catheter shaft having an axial length, the catheter shaft including an inner liner, a reinforcing structure located outside the inner liner, and a tubular outer layer extending over the reinforcing structure; the tubular outer layer includes a plurality of segments of material, each segment of material having a respective width measured along an axial length, the plurality of segments of material extending in a helical direction along the axial length to form a continuous wall of the tubular outer layer; wherein the plurality of material segments includes a first material segment, a second material segment, and a third material segment, wherein structural properties of each of the first material segment, the second material segment, and the third material segment are different; and the tubular outer layer has a first transition region, wherein a width of at least one of the first, second, or third sections of material varies across the first transition region resulting in a change in a structural property of the first transition section.

Further variations include a medical tubing comprising: a tubular layer comprising a plurality of segments of material, each segment of material having a respective width measured along an axial length, the plurality of segments of material extending in a helical direction along the axial length to form a continuous wall of the tubular outer layer; wherein the plurality of material segments includes a first material segment and a second material segment adjacent the first material segment, wherein a structural property of the first material segment is different from a structural property of the second material segment; and a first longitudinal region of the tubular outer layer, wherein the width of the first material and the width of the second material both vary along the first longitudinal region resulting in a variation of the structural property over the first longitudinal region.

The medical tube may further include a tubular outer layer including a plurality of segments of material, each segment of material having a respective width measured along an axial length, the plurality of segments of material extending in a helical direction along the axial length to form a continuous wall of the tubular outer layer; wherein the plurality of material segments includes a first material segment, a second material segment, and a third material segment, wherein structural properties of each of the first material segment, the second material segment, and the third material segment are different; and the tubular outer layer has a first longitudinal area, wherein a width of at least one of the first, second, or third sections of material varies over the first longitudinal area resulting in a change in a structural property of the first longitudinal section.

Another variation of medical tubing includes: a catheter shaft having an axial length, the catheter shaft including a liner, a reinforcing structure located outside the liner, and a tubular outer layer extending over the reinforcing structure; the tubular outer layer includes a plurality of segments of material, each segment of material having a respective width measured along an axial length, the plurality of segments of material extending in a helical direction along the axial length to form a wall of the tubular outer layer, the tubular outer layer having a first longitudinal region, a second longitudinal region, and a transition region between the first longitudinal region and the second longitudinal region; wherein in the first longitudinal region, the plurality of material segments includes a first material segment and a second material segment, wherein a structural property of the first material segment is different from a structural property of the second material segment such that the first longitudinal region has a first structural characteristic; wherein at the transition region, the second section of material terminates at an end and a third section of material is joined to the end of the second section of material, wherein a structural property of the second section of material is different from a structural property of the third section of material; and wherein the first section of material and the third section of material extend helically from the transition region to the second longitudinal region such that the structural properties of the second longitudinal region are different from the structural properties of the second longitudinal region.

The present disclosure also includes one or more methods of forming a polymeric tube. For example, such a method may include winding a plurality of polymer strands into a helical configuration, forming a polymer tube, wherein at least two polymer strands include different structural properties; wherein in a first section of the polymeric tube, the plurality of polymeric strands form a first sequence; changing the sequence of the polymer strands to form a second sequence in a second segment of the polymer tube; and fusing each polymer strand to an adjacent polymer strand to form a continuous wall in the polymer tube, wherein the continuous wall defines a lumen therethrough, and wherein a structural property of the first segment differs from a structural property of the second segment due to a difference in the first sequence and the second sequence.

Another catheter according to the present disclosure includes: a liner; an outer layer comprising a plurality of polymer strands wound in a helical configuration, wherein at least two polymer strands comprise different structural properties; wherein in a first section of the outer layer, the plurality of polymer strands form a first sequence; wherein in a second section of the polymeric tube, the polymeric strands form a second sequence; and wherein each polymer strand is fused or joined with an adjacent polymer strand such that the plurality of polymer strands form a continuous wall defining a lumen through the polymer tube, and wherein the structural properties of the first segment differ from the structural properties of the second segment due to differences in the first and second sequences.

Another variation of the catheter includes: a liner; an outer layer comprising a first polymeric material having a tubular shape, at least a second polymeric strand wrapped around the tubular shape in a helical configuration and fused into the first polymeric material such that at least a portion of a wall of the tubular shape comprises the first polymeric material and the second polymeric material, wherein the first polymeric material and the second polymeric material comprise different structural attributes; wherein in a first section of the outer layer, the first and second polymeric materials form a first pattern; wherein in a first section of the outer layer, the first and second polymeric materials form a first pattern; and wherein each polymer strand is fused or joined with an adjacent polymer strand such that the plurality of polymer strands form a continuous wall defining a lumen through the polymer tube, and wherein the structural properties of the first segment differ from the structural properties of the second segment due to differences in the first and second sequences.

The conduit and tubing configurations of the present disclosure allow for a significant number of combinations and permutations of different variations of conduits, as well as combinations of various aspects of these structures. It is contemplated that any of the following claims and elements may be combined with any independent claim without the claims being inconsistent with each element.

Any of the structures herein can include a tubular outer layer including a plurality of segments of material, each segment of material having a respective width measured along an axial length, the plurality of segments of material extending in a helical direction along the axial length to form a continuous wall of the tubular outer layer.

Any variation of the apparatus/method may also include a liner positioned within the tubular outer layer, and a reinforcing structure positioned outside the liner and within the tubular outer layer.

Variations may include the width of the first section of material and the width of the second section of material varying along the first transition region.

Variations may include the tubular outer layer having a proximal longitudinal region proximal to the first transition region, wherein the proximal longitudinal region is formed entirely of the first section of material.

Variations may include a third segment of material extending over a majority of the axial length of the tubular body of the catheter.

Variations may include, in at least a first section of the wall of the tubular body, a width of the first section of material being greater than a width of the second material.

Variations may include tapering the end of the second section of material.

The conduits and structures described herein may have sections of material with right-hand windings, left-hand windings, or both.

Variations of any of the devices or methods herein can include at least one section of material comprising a non-fusible material. Furthermore, such non-fusible materials may be used for manufacturing only, and thus removal of the non-fusible material may impart a groove cavity or other design feature on any surface of the device.

The devices herein may also include a liner positioned within the tubular outer layer, and a reinforcing structure positioned outside the liner and within the tubular outer layer.

Variations of the device structures herein may also include a tubular outer layer further having a second longitudinal region, a third longitudinal region, and a transition region between the second longitudinal region and the third longitudinal region; wherein the second longitudinal region includes a first section of material and a second section of material defining a structural characteristic of the second longitudinal region; wherein at the transition region, the second section of material has an end and a third section of material is joined to the end of the second section of material, wherein the structural properties of the second section of material are different than the structural properties of the third section of material; and wherein the first and third sections of material helically extend from the transition region to the third longitudinal region resulting in a structural characteristic of the third longitudinal region that is different from a structural characteristic of the second longitudinal region.

The catheter or catheter structure of any of the preceding examples may include a tubular outer layer including a plurality of segments of material, each segment of material having a respective width measured along an axial length, the plurality of segments of material extending in a helical direction along the axial length to form a continuous wall of the tubular outer layer. Further, the change in any material segment may be incremental or continuously variable.

Brief Description of Drawings

FIG. 1A shows a generic catheter structure and shows a cross-sectional view of a catheter segment constructed on an inner extruded tube.

Figure 1B provides an illustration of a catheter body that exhibits a curved profile.

Fig. 1C shows a conventional catheter having multiple stiffness regions.

Fig. 1D shows a representation of a photograph of a catheter having abrupt changes in structural properties between regions and held to assume a curved or curvilinear profile such that abrupt changes in the catheter result in irregular bend radii.

Figure 2A shows a partial cross-sectional view of an improved catheter comprising an improved polymeric outer layer.

Fig. 2B illustrates the concept of a catheter shaft intended to illustrate features of a catheter design according to the present disclosure.

Fig. 2C illustrates various pathways through which variations of the catheter segments of the present invention are specifically designed to traverse.

Fig. 2D illustrates three conduits having sections of material that are coiled in left-hand and right-hand directions.

Fig. 2E illustrates various cerebral vessels with a catheter advanced through one of the carotid arteries.

Fig. 2F illustrates the situation when a conventional catheter is advanced through the carotid artery, wherein the conventional catheter comprises different segments with abrupt changes between the segments.

Fig. 2G and 2H illustrate the shape of the improved catheter as it is advanced in the vessel of fig. 2E and assumes the shape of the vessel.

Figure 2I illustrates one possible design configuration for making a conduit structure using a composite conduit having sections of material that comprise different materials, each material providing different mechanical advantages/benefits all within a single region of the finished conduit.

Fig. 3A and 3B illustrate one example of a manufacturing process for constructing a catheter segment according to the present disclosure.

Fig. 3C illustrates a catheter segment comprising a plurality of discrete strands of polymeric material wrapped around a mandrel or tube.

Fig. 3D illustrates an image of an example of a winding process.

Figure 3E illustrates a configuration in which the polymer strands are secured together prior to helical winding.

Figure 3F illustrates three additional variations arranged into polymer strands having different properties.

Fig. 3G and 3H illustrate additional variations of polymer strands joined together end-to-end and longitudinally prior to being spirally wound and formed into a tubular body.

Fig. 3I and 3J depict additional variations of non-uniform strands joined together prior to forming a tube for a conduit structure.

Fig. 4A illustrates another variation of a set of strands prior to forming the tubular segment shown in fig. 4B.

Fig. 4B illustrates a catheter segment formed from the strands shown in fig. 4A.

Fig. 5 shows a catheter segment illustrating the separation of dissimilar strands.

Fig. 6A to 6C show a variant of the strand with a reinforcing structure.

Fig. 7A-7F illustrate some examples of catheter segments formed from various polymers.

Fig. 8A and 8B show pictures of strands extending near the scale to illustrate perspective views of strands for one variation of the catheter structure.

Fig. 9A and 9B show two examples of catheter segments having an outer layer that may be bonded to the catheter or used as a stand-alone device.

Fig. 10A-10D illustrate another variation of the device that incrementally changes the polymer to construct a coiled catheter with gradually changing transition regions between different sections of the finished polymer tube.

Fig. 11A illustrates a graph of bending stiffness versus shaft position to aid in understanding the ability of the catheter of the present disclosure to create a transition region that is a significant improvement over currently available catheters.

Fig. 11B shows an image of a catheter segment constructed in accordance with the disclosure herein, wherein the catheter segment is held in a pose similar to the pose of the catheter shown in fig. 1C.

Fig. 12A and 12F show images of various catheters to illustrate variations in patterns that may be formed with joined polymer strands to create features and/or patterns in catheter segments.

Fig. 13A and 13B illustrate a plurality of material segments in which additional discrete material is formed.

Figures 14A-14C illustrate another variation of a composite polymeric tube having multiple material segments embedded therein.

Fig. 15A illustrates a variation of a catheter with a mixing region.

Fig. 15B shows an enlarged view of the blood vessel in region 15B of fig. 15A.

Fig. 15C illustrates an enlarged view of the catheter of fig. 15A through an acute bend in an artery.

FIG. 15D illustrates a number of non-exhaustive design configurations that produce a blending region as shown in FIGS. 15A and 15C.

Detailed Description

The catheter configurations discussed herein may be used in a variety of devices where different regions are selected for customization of attributes. The configurations described herein may be incorporated into various medical devices or may be used as a catheter shaft. Furthermore, in some variations, the construction features of the present disclosure are not limited to in vivo medical devices, and may be used with any device requiring a conduit.

The polymeric conduits described herein may be constructed in any manner that allows for the configuration (and mixing region) of the material segments disclosed below. Such manufacturing methods include, but are not limited to: forming a polymer tube by winding directly on a catheter shaft; forming the strands into a composite sheet and then winding the sheet onto a structure to complete the catheter shaft; and/or the ribbon/strand is first wound onto a mandrel or support structure and then the material is fused into a tube and then transferred to a catheter assembly.

Fig. 2A shows a partial cross-sectional view of an improved catheter 100, the improved catheter 100 including an improved composite outer layer 103 as described herein. The catheter structures discussed herein may incorporate any number of features known to those skilled in the art of catheter structures. Such features are omitted herein so that the focus may be on explaining the composite outer layer 103 of the improved catheter. Further, the improved catheter structures disclosed herein may be incorporated into any number of catheters that may benefit from the customization of the features provided by the improved polymeric outer layer 103. For example, such catheters include, but are not limited to, distal access catheters, sheaths, guide catheters, balloon catheters, intracranial support catheters, microcatheters, arterial catheters, central venous catheters, pulmonary arterial catheters, coronary and cardiac catheters, and peripheral catheters, among others.

Other variations of the improved structure may be used with any polymeric tubular structure. It should be noted that any conduit structure or polymer tubing disclosed herein is not limited to a single uniform outer diameter throughout the conduit. As described below, the conduits and polymer pipes of the present disclosure may have a corrugated outer diameter. Alternatively or in combination, the outer diameter may vary over various longitudinal regions of the catheter. The term longitudinal region means a region of any length along the axis 105 of the pipe structure. The catheter structures and tubular structures disclosed herein may have any number of conventional cross-sectional shapes. For example, variations of the device may include catheters having different diameters and/or cross-sectional shapes in different regions. Some sections of the catheter and tubular structure may include a circular cross-sectional shape that changes to a non-circular shape.

As shown, in one variation of this device, the tubular structure or shaft of the catheter 100 extends from a hub 101 and may be formed of a modified outer composite layer 103 covering a braid 20, coil or other support structure commonly used in catheters, as described below. The braid 20 is positioned around the tubular liner 14 (typically constructed of PTFE, although other materials are within the scope of the present disclosure). As shown in fig. 2A, the modified composite layer 103 is the outermost component of the conduit pipe. As described below, the improved composite layer 103 may include any number of longitudinal regions that are better suited for transmitting torque through the catheter 100. Locating these torque-transmitting polymer regions on the exterior of the catheter increases the effectiveness of the torque-transmitting regions compared to conventional catheters that rely primarily on the braid 20 located within the catheter shaft.

Fig. 2B illustrates the concept of a conduit layer 103, which is intended to illustrate features of a conduit design according to the present disclosure. Layer 103 may be incorporated into a catheter structure as shown in fig. 2A, or into any variation of such a structure (e.g., a catheter without reinforcing structure 20 and/or a catheter without liner 14). As shown, the conduit layer 103 may include any number of regions 102, 104, 106, and 108, wherein the structural properties of each region may be customized based on the intended purpose of the conduit or according to other needs. For example, the layer 103 shown in fig. 2B may be optimized or matched for use in a catheter intended to be advanced through vasculature having a variety of curvatures. In the example shown, referring to fig. 2C, region 102 may be designed to traverse tortuous region 52, while regions 104, 106 and 108 may be designed for respective regions 54, 56 and 58. Fig. 2B shows that the conduit layer 103 has at least one segment of material extending in a spiral or helical pattern with a pitch that varies along the length of the finished layer 103. In one variation, the various longitudinal regions 102, 104, 106, 108 may match specific regions of the vasculature 52, 54, 56, 58, each having a different degree of tortuosity. As described herein, layer 103 may include any number of segments of material. Furthermore, the actual material of any material segment (e.g., 110, 112) over the length of layer 103 may vary, which may create new regions.

Fig. 2B also shows that the segment of material 110 includes a polymer spiral region extending adjacent to the second segment of material 112, the second segment of material 112 including a second polymer (or alternative catheter material) to create the regions (102, 104, 106, 108) to achieve the desired properties extending along the catheter 100. For example, the pitch of first material segment 110 may vary in each of regions 102, 104, 106, and 108. Alternatively, or in combination, the width of any material segment may vary depending on the region. For example, material segment 110 may include a reinforcing polymer (e.g., PEBAX 72D or similar material).

In another variation, the section of material 110 may include a first polymer material (e.g., PEBAX 35D) within a second section of material 112, the second section of material 112 including a relatively harder material (e.g., PEBAX 40D-70D), wherein the helical pitch of the section of material is selected such that the first region 102 is relatively harder compared to the remaining regions, and the adjacent region 104 has a reduced hardness relative to the region 102. This change in stiffness may continue until region 108 is the softest/least stiff region and serves as the distal portion of material layer 103, which in turn similarly affects the distal portion of the catheter incorporating material layer 103.

The structure of layer 103 of the present disclosure allows for any number of engineered conduits having customized properties. Fig. 2D shows two layers 103 and 107 to illustrate that the novel layers of the present disclosure provide the ability to manufacture catheter structures having both left-hand (layer 103) and right-hand (layer 107) winding directions of material segments 110, 112 to create directionally-biased catheters having opposite winding characteristics between a distal region 122 and a proximal region 124. In a first variation, shown in fig. 2D, layer 103 may be used for catheters requiring diversified regions 102, 104, 106, 108. However, in this variation, region 108 includes a section of material 110, which section of material 110 has a loose pitch that is wound in the right-hand direction and includes rigid polymer strands to create a soft region that can be used to form the distal region of the catheter. The adjacent region 106 includes a more moderate pitch of the material segment 110 such that the region 106 is not as soft as the region 108. The pitch of material segments 110 may be increased in segments 104 and 102, which allows for increased support. Although the 2D drawing only shows two segments of material 110 and 112, any number of segments of material formed from a polymeric material may be used to make the various segments that form the outer layer 103 of the catheter. As described above, the structural characteristics of the various regions may be matched to the characteristics of the target anatomy. Further, the wrapping (or particular material selection) of the material segments 110 and/or 112 shown in layers 103 or 107 may result in a catheter that is wrapped in a particular direction (i.e., a wrapped catheter that is predisposed to follow a particular region of the anatomy). Specifically, the directionality of the coiling may be matched to the directional distortion of the vessel (i.e., left-hand coiled catheters for the left internal carotid artery and vessel, and right-hand coiled catheters for the right internal carotid artery and vessel, etc.). For example, the left carotid artery of an individual is coiled in the left-hand direction, while the right carotid artery of the individual is coiled in the right-hand direction. The catheter structure using the disclosed catheter layers (e.g., 103, 107) results in a catheter that is adapted to specifically follow the curvature of a particular internal carotid artery or any other artery or body passageway. Generally, as described herein, the direction of the reinforcing strands may be pre-set to bend or navigate the catheter in a particular rotational direction within the anatomy. As described herein, the present disclosure allows for tailoring any region of a catheter structure with specific material properties. Further, the catheter layer 114 comprises a single tube with a right hand winding adjacent the distal end of the layer 114 and a left hand winding adjacent the proximal end of the layer 114. Clearly, the present disclosure includes material segments that are wound in a single direction or multiple directions along the length of any conduit.

Fig. 2E, 2G, and 2H further illustrate the benefits of using a catheter of the configurations disclosed herein. Fig. 2E illustrates various cerebral vessels, with the catheter 10 advanced through one of the carotid arteries 4, the carotid artery 4 typically being used for access to the brain. The carotid artery 4 has various curved regions and decreases in diameter as the vessel proceeds further into the brain. Fig. 2F illustrates a conventional catheter advanced through the blood vessel 4 of fig. 2E and assuming the shape of the blood vessel 4. The catheter 10 is similar to the structure shown in fig. 1A, in that the catheter includes discrete regions 21, 22, 24, 26, 27 of varying stiffness. As noted above, although conventional catheters are designed with different regions, each region has a discontinuous change in polymer (or other feature, such as removing a liner, changing the braid/coil structure, etc.), and thus catheter 10 has an abrupt change in structural properties at the intersection of each region 21, 22, 24, 26, 27. One problem with this design is the loss of torque that is evenly applied to the individual segments. In other words, the torque 40 exerted on the harder proximal segment 27 will be greater than the torque 42 of the distal-most segment 21, with the distal-most segment 21 being the most flexible segment in general. In addition to the difference in torque, the rotational deflection of the proximal segment 27 will be greater than the rotational deflection of the distal-most segment 21.

Fig. 2G and 2H illustrate the situation when the modified catheter 100 is advanced in and assumes the shape of the blood vessel 4 of fig. 2E. Fig. 2G shows a variation of the catheter 100 of the present design, but for illustrative purposes only shows the first material segment 110 helically wound with the second material segment 112. Any number of material segments may be used in catheter 100, as described herein and shown in fig. 2H. For illustrative purposes, material segment 110 comprises a single polymer having rigid material properties (e.g., 72D). The example shows the first section of material 110 having a polymer that extends the length of the catheter 100. Thus, the helically formed polymeric strand material segment 110 helps to transmit the applied torque 44 along the length of the catheter 100 through the material segment 110 such that the torque 46 at the distal end is closer to the torque 44 at the proximal end, unlike conventional catheters.

Fig. 2H shows another variation of catheter 100 having multiple material segments 110, 130, 132, 134, 136, 138, 140, 142 extending helically along the length of catheter 100. The segments of material shown in fig. 2H are for illustration purposes only, and any number of polymers may extend helically around the catheter 100, with some polymers stopping or tapering at different regions and different polymers starting, such that different regions of the catheter may include different polymers to impart unique structural properties to each region of the catheter. Fig. 2H is intended to illustrate the ability to position material combinations along any section of catheter 100. To illustrate one variation of the catheter 100, the material section 110 of the catheter forms a majority of the wall of the material layer at the proximal end 122 of the catheter 100 (see, e.g., 103 in fig. 2A). The polymer forming the material layer 110 at the proximal end 122 of the catheter 100 extends helically along the length of the catheter 110, and the material or change or section of material terminates adjacent the distal end 124 of the catheter 100 such that the section of material at the distal end 124 comprises different sections of material 130, 132 or different polymers. As described herein, a material segment may be terminated, or the polymers in the material segment may be joined to the ends of different polymers in the material segment, such that the polymers in the same material segment change.

Fig. 2I illustrates one possible design configuration for making a conduit structure using a composite conduit 103 having sections of material comprising different materials, each material providing different mechanical advantages/benefits all within a single region of the finished conduit. The result is that the finished catheter segment will achieve mixed mechanical characteristics in one region of the catheter. This configuration is simply not possible with conventional catheter designs. For example, fig. 2I illustrates a composite layer or tube 103 having a plurality of material segments 280, 282, 284, 286, and 288. These material segments may each provide unique benefits: material segment 280 comprises a low durometer ultra soft material for high flexibility; the material segments 282 comprise a moderate durometer material that provides some flexibility and axial stability; the material segments 284 include a high hardness material that provides enhanced torque control as well as rotational and axial stability. Material segments 286 and 288 are shown to represent that composite tube 103 may include any number of additional layers of material.

The various polymer strands used to make the catheter (or outer layer) may be selected based on the intended use of the catheter and/or according to the intended path of the target in the body to impart desired characteristics to the catheter 100. This structure allows for various properties of any polymer to extend throughout various sections of the catheter 100 or the entire catheter 100 such that the catheter does not contain any abrupt change regions of structural properties/attributes that affect rotational and axial stability, such as bending, twisting, contraction, etc.

Fig. 3A and 3B illustrate an example of a manufacturing process for constructing a catheter segment according to the present disclosure. Any manufacturing process that produces a conduit or conduit layer having multiple sections of material is contemplated to be within the scope of the present disclosure. For example, such manufacturing processes may include wrapping polymer strands (as shown), 3D printing, extrusion, and the like. As shown in fig. 3A, a plurality of polymer strands or ribbons are placed in some manner to conform to the material segments 130, 132, 134, 136 and may be wrapped around the structure 116. The structure may comprise a braid/liner of a mandrel, tube or catheter structure. Once the polymer strands are wrapped, they are fused or otherwise joined together to form a layer as described herein (see, e.g., layer 103 of fig. 2A). In one variation, the wrapped and joined polymeric tapes form the wall layers of the catheter after they are fused together. Alternatively, the polymeric band may form an outer layer over the tube, braid and/or coil 116 and form a portion of the catheter section. For convenience, the polymer strands/tapes/extrusions should be referred to as polymer strands. The present invention includes polymer segments having any shape desired to complete a catheter segment. As shown, the polymer strands may be rectangular in cross-section. Alternatively, the polymer strands may be oval, round, or any other shape. In further variations, polymer strands of different shapes and sizes may be combined to form a layer. In addition, the polymer strands may comprise a single lumen extrudate/tube that shrinks and melts/fuses. Alternatively, the strands may be extruded or otherwise manufactured to be solid. In another variation, the lumen of each polymer strand remains intact. In a typical variation, the strands are wound around a braid or coil (as described above). In further variations, the polymer strand structures discussed herein may be used to form an inner layer of a catheter (instead of or in addition to a polymer liner), with a separate structure being used for the outer layer of the catheter. In further variations, although the disclosure herein discusses strands and segments of material comprising polymers. The strands or segments of material may comprise a non-polymeric material (e.g., metal, stainless steel, alloys, Liquid Crystal Polymer (LCP), fibers, composites, or other similar structures). The strands may be of different materials, shapes, sizes, and mixed together, or may be placed and removed to leave voids. The strands may also be of different materials, shapes, sizes, and mixed together, or may be placed and removed to leave voids.

For purposes of explaining features of the invention, polymer strands/components are representative of the segments of material described herein prior to formation into the tubular wall. As described herein, in some variations, the material segments may be formed from the first polymeric material and extend in a helical pattern. At some point, the first polymeric material terminates at one end and is joined to one end of the second polymeric material, which still extends or continues in the helical pattern of material segments. In this case, a material segment is considered to have two different polymeric materials in different longitudinal regions. In a further variation, the segments of material comprise a polymeric material and extend helically within a longitudinal region of the conduit and then terminate such that adjacent segments of material are joined together to maintain continuity of the walls of the resulting conduit.

Regardless of the manufacturing process, the polymer strands in each material segment 130-136 may include polymers of different compositions. In one example, the polymer may be a common material (e.g., PEBAX), wherein each strand in the respective material segment 130 and 136 comprises a different durometer. For example, the strands may have the following relative stiffness: 130-72D, 132-63D, 134-35D, and 136-45D. It is apparent that any number of variations are within the scope of the disclosure.

Fig. 3A also shows a plurality of material segments 130, 132, 134, 136, each having a respective width W1, W2, W3, and W4, measured along the axial length 105 of the tube. In this illustration, axial length 105 is the axial length of the core or tube, which is substantially similar, if not the same as the axial length of a finished tube or conduit having layers formed from material segments 130, 132, 134, 136. In the case where the material has not yet formed a tube structure, the width is measured in a plane perpendicular to the strand length. As shown in fig. 3B, the segments of material extend in a helical direction along the axial length 105 to form a continuous wall as described herein.

Fig. 3C shows the wall segment 103 and the support structure 116 after multiple discrete strands of polymeric material in the material segments 130, 134, 132, 136 are joined together. The segments 103 may be incorporated into medical catheters, medical devices, and/or other conduits.

Fig. 3D shows an image of one example of a winding process in which polymer strands form the segments 138, 140, 142 of material and are wound directly onto the catheter reinforcing braid 116. (alternatively, the strands may be wound on a mandrel, fused or partially fused together, and then transferred to the catheter braid as a conventional catheter structure). In this variation, the strands 138-142 are separate and are wrapped such that the strands contact to fuse.

Figure 3E illustrates a configuration in which the polymer strands 130-134 are secured together to form the material segments 130-134 prior to being helically wound. For example, the strands may be fused together or pinned together prior to winding.

Figure 3F illustrates three additional variations of polymer strands arranged to have diverse properties. In the illustrated example, the stiffness of the strands is shown. However, the polymer strands may vary in other properties as desired. As shown in the bottom two variations, two strands having similar configurations may be placed adjacent to dissimilar strands. When forming the tubular member, the central section of material will be defined by sections of material having the same polymer.

Fig. 3G and 3H illustrate additional variations of the polymer strands 130, 132, 134, 130 and 134 that are joined together end-to-end and longitudinally prior to forming the wall, where the strands 134 will ultimately form sections of material on either side of the section of material formed by the strands 130 and 132. In this variation, the strands 130 and 132 are joined end-to-end at the transition section 120 to allow for material transition longitudinally along the axis of the finished catheter. This means that when the tubular member/wall is formed, the central section of material comprises material 130 joined to material 132 at edge 120. The joint or transition segment 120 between the strands 130 and 132 may be an abrupt transition segment 120 as shown in fig. 3G, or a tapered or conical transition segment 120 as shown in fig. 3H.

Fig. 3I and 3J depict additional, but non-exhaustive, variations of the strands 130, 132, 134, 136 being joined together in the event that the strands are not uniform. For example, fig. 3I shows strands 134 having a circular cross-sectional shape. As mentioned above, any type of cross-sectional shape may be used. In this case, the width W3 of the strand 134 may be considered to be its widest dimension along the axis. In some variations, the size of the strands 134 will cause the resulting section of material to protrude slightly from the surface of the tube. This is illustrated in fig. 3J, where the height H1 of some of the strands 134 engages the strands 132 having a greater height H2. Fig. 3J also shows that the strand widths W5 and W6 are not uniform. Likewise, any arrangement of shapes, sizes, widths, heights, etc. may be combined to form a polymer layer. It should be noted that any strand of material incorporated into the composite polymeric layer may include a strand of material having a melting temperature different from one or more adjacent strands. It should also be noted that in some variations, one or more of the strands may be infusible (i.e., a thermoset material, or a metal, teflon, etc.), such strands being mechanically fixed by adjacent strands, but not melted. In a further variation, the infusible strand is used during the formation of the pipe and then removed to create a void or pattern.

Fig. 4A illustrates another variation of the set of bonding strands 130 and 138 prior to forming the tubular segment shown in fig. 4B. As shown, the strands include different properties, which in turn result in different sections 102, 106, and 108 for the catheter. As shown in fig. 4B, the variation in the composition of the material segments 130 and 138 forms different axial segments 102, 106, 108 extending longitudinally along the tubular layer 103 when wound. In both variations shown in fig. 4A and 4B, the strand/tubular layer 103 includes a single strand 130, and the single strand 130 will extend continuously as a segment of material 130 throughout the length of the finished tube 103. In this example, the strand 130 comprises 72D material and may ultimately be used as a reinforcement of the finished catheter. (primarily for transmitting torque and providing stability through the generally soft and pliable distal region, which generally does not transmit torque well and generally has poor stability).

FIG. 5 shows a segment 102 of a conduit in which strands 152 and 154 are joined together to form a tube. The figure shows the separation of dissimilar strands 152 and 154. In this example, the strands 152 may be separated by a second strand 154, where the second strand either includes a section having the same width as the strands 152, or the second strand 154 has a greater width than the first strand 152. As noted above, the width is measured along the axial length of the tube. For example, the strands 152 may comprise a high durometer material, while the strands 154 comprise a relatively lower durometer material. In another variation, the strands 152 comprise a low durometer material and the strands 154 comprise a high durometer material. For example, in one variation of the device, the low durometer material may range between 35D and 45D, while the high durometer material may range between 63D and 72D. Obviously, additional variations of materials are within the scope of the present disclosure.

Fig. 6A illustrates another variation of the catheter structure described herein, wherein the polymeric strands 130 include support members 156 extending therethrough, the support members 156 reinforcing the strands 130 or providing alternative structures and properties. The support member 156 may extend through the entire length of the strand 130 or partially through the strand. Further, variations of the reinforcing strands 130 may include a plurality of support members extending through the strands. Fig. 6B shows a cross-sectional view of the strands 130 to illustrate some of the cross-sectional shapes of the reinforcing members. As shown, the stiffening member may have a circular 158 or elliptical cross-section, the support member may have a rectangular or square 160 cross-section, or the support member may include a D-shaped 162 cross-section. The support member may comprise a metal, alloy or polymer. For example, the support member may comprise SS wire, shape memory wire, drawn filled tube, or composite fiber material. It may be a cable, braid, coil, strand, etc., or any shape/structure/material used to provide support. Fig. 6C illustrates various complex cross-sectional shapes 164 for support members within the strands 130. In certain variations, a catheter segment may include different cross-sectional shapes in different segments of the catheter. For example, it has been found that strands having a circular or oval cross-sectional shape are more suitable for the distal region of the catheter, while strands having D-shaped support members are useful in the middle or proximal region of the catheter.

Fig. 7A-7F illustrate some examples of tubular segments 203 formed from various polymers to have multiple material segments extending in a helical pattern along the tube 203. For purposes of illustration in fig. 7A through 7F, the material properties are shown in association with the following element numbers: 35D-235, 45D-245, 55D-255, 63D-263 and 72D-272. However, this association is intended to demonstrate a variation of the conduit 203. Any material variation may be used in the catheter structures described herein. Further, as described herein, any conduit segment 203 may be used for any section of a complete conduit. The illustrations of fig. 7A-7F are intended to illustrate a non-exhaustive combination of sections. In each figure, the pattern illustrated by the respective material segments 235, 245, 255, 263, 272 is repeated to provide unique attributes to that section of the pipe 203. For example, fig. 7B illustrates a pattern in which a 55D section of material 255 is located directly between two 45D sections of material 245, and the assembly is located between two 35D sections of material 235. This configuration may provide the property of allowing a "shock absorber" effect. In fig. 7C, 7D, 7E and 7F, during construction of the conduit 203, some of the strands are doubled to provide a wider section of material having this configuration. For example, material segment 235 in fig. 7D is shown as being approximately twice the width of material segments 245, 255, and 263. Fig. 7E shows that section of material 255 is almost twice as wide as sections 263 and 270. Fig. 7F shows that material segments 245 and 255 are almost twice as wide as segment 263. Also, the illustrated variations are intended to provide a non-exhaustive sample of variations for possible catheter configurations.

Fig. 8A and 8B show examples of strands 130 and 132 extending about scale 30 to illustrate a perspective view of one example of strands 130 and 132, the strands 130 and 132 ultimately forming a tubular member as described above, wherein the overlapping or staggering of the polymer end fitting locations produces a finished polymer tube/conduit structure with transition regions 129 that is a significant improvement over conventional conduit structures. Fig. 8A and 8B illustrate the overlap or staggering of the polymers at the individual transition segments 120 (where the materials each have a butt joint location) such that the ends of 130 abut the ends of 134, and when wound, will result in a transition region 120 that is significantly improved over the conventional catheters described above. As shown, the configuration of fig. 8A includes staggered transition segments 120, which results in a transition region 129 similar to that shown in fig. 9A. As strands 130 and 132 form a tubular member, strands 130 collectively form a segment of material that changes from a first material to a second material having the material of strands 132 over region 129, as described herein. Fig. 8B shows a variation of the example similar to fig. 8A, where the strand 134 is joined/spliced end-to-end with the strand 130. However, the strand 136 remains continuous. When manufactured as a tubular member, the strands 134 form material segments of varying material as described with reference to fig. 8A, but the tube segments formed by fig. 8B include material segments formed by strands 136 that remain unchanged.

Fig. 9A and 9B show two examples of catheter segments having an outer layer 103 that may be bonded to the catheter or used as a stand-alone device/structure. Fig. 9A shows a material segment 130 formed from a first polymer and a material segment 132 formed from a second polymer. The outer layer 103 includes a longitudinal region 129 of the tubular layer, wherein the width of the first section of material 130 and the width of the second section of material 129 both vary in width along the longitudinal region 129, resulting in a change in structural properties over the first longitudinal region 129. As shown, the right side of fig. 9A includes a tubular member formed entirely of material segments 130, and the left side includes a tubular member formed entirely of material segments 132. In transition region 129, the width of each section of material varies inversely along longitudinal region 129 such that as the width of first material 130 decreases to the left, the width of the second section of material increases. By adjusting the length of the segments 129, and by adjusting the number of strands/ribbons used, these transition regions can be made as long and more gradual as desired, providing a significantly improved and better transition region as compared to conventional catheters.

Fig. 9B shows a variation of the conduit 103, the conduit 103 having a plurality of material segments 130, 132, 136 helically wound to form the conduit 103, wherein the conduit 103 includes a joint 120 where the material segment 130 becomes a different material 134, the material 134 continuing in a helical pattern of the material 130. This end-to-end joining of materials allows the material segments to continue while the material is being replaced.

Fig. 10A to 10D show another example of an arrangement of strands forming a tubular member for a catheter. Fig. 10A and 10C show a set of engagement strands that can be varied to produce the configurations shown in fig. 10B and 10D, respectively. Fig. 10A shows a 5-strand structure in which one end of the splice strand includes a first polymer strand 204. Each of the first polymeric strands 204 is replaced at a separate transition segment 120, the transition segments 120 being staggered to gradually replace the strands 204 with the second polymeric strands 206 over a transition region including the lengths 172, 174, 176, and 178. This configuration allows the transition regions 172, 174, 176, and 178 to gradually change along the finished tubular assembly 103 (shown in fig. 10B), which finished tubular assembly 103 has the properties of the first polymer in the first longitudinal region 170 and gradually changes to the properties of the second polymer over the transition regions 172, 174, 176, and 178 until the longitudinal region 180 includes all of the second polymer. The material transitions in the longitudinal regions 172, 174, 176, 178 represent examples of gradual transitions in material properties over the longitudinal transition regions of the tubular assembly 103 or the finished catheter structure. It should be apparent that any number of material segments or widths of material segments may be used to increase or decrease the rate of material property transition. Moreover, variations of the devices described herein do not require the interleaving of transition segments 120. While interleaving is generally required to obtain a gradual transition, the transition region may include abrupt changes in material when desired.

It should be noted that transition segments should be used to describe the change of one or more strands of material from a different material. The term transition region shall describe the overall effect of one or more transition segments. In some variations, the transition region does not include any transition sections that result from the material simply terminating. Thus, the catheter structure of the present disclosure may have a transition region that gradually changes material properties over the axial length, or, alternatively, the transition region may be a region of abrupt change in material properties.

Fig. 10B also shows that each longitudinal region 172, 174, 176, 178 includes at least two material segments 204 and 206, wherein the width of one material segment 204 or 206 is increased or decreased and the width of the other material segment 206 or 204 is decreased or increased accordingly. The variation of tube 103 shown in FIG. 10B also includes longitudinal regions 170 and 180 that are formed entirely of a single section of material. Likewise, any of the tube structures 103 discussed herein may be incorporated into a catheter structure as shown in fig. 2A, or such a tube structure 103 may be incorporated into any medical device or non-medical device.

As shown, the catheter segments may include various segments: segment 170 is composed of 5 strands of the first polymer (5 and 0); segment 172 is composed of 4 strands of a first polymer and 1 strand of a second polymer (4 and 1); segment 174 includes 3 strands of a first polymer and 2 strands of a second polymer (3 and 2); segment 176 includes 2 strands of a first polymer and 3 strands of a second polymer (2 and 3); segment 178 includes 1 strand of a first polymer and 4 strands of a second polymer (1 and 4); and segment 180 includes 5 strands of a second polymer (0 and 5). The configuration of fig. 10A results in the conduit shown in fig. 10B in which the strands are helically formed and melted into the conduit segments.

Fig. 10C shows a plurality of joined strands, where a segment 190 includes 4 strands 208 of a first polymer and a single strand 210(4 and 1) of a second polymer. As shown, in the variation of the region 192, one strand 208 tapers, leaving only four strands (3 and 1). In the next segment 194, the other strand 208 tapers, leaving only 3 strands (2 and 1). The process continues to segments 196(1 and 1) until a second polymer strand 210 remains. The twist of the engaging strands is adjusted (e.g., pitch is changed) so that the reduction in the number of strands does not leave any openings or gaps between the strands. This structure produces a tubular structure 103 similar to that of fig. 10D. As shown, tubular structure 103 includes two sections of material in longitudinal region 109, with section of material 210 having a width that increases in section 192 relative to section 190, and section of material 208 having a width that decreases in section 192 relative to section 190. The widths of material segments 208 and 210 continue to vary inversely across longitudinal regions 194 and 196 until region 198 includes a single material segment 210. The configuration shown in fig. 10D shows a tubular segment 103 having transition regions 192, 294, 196 in which the material segment changes, but there is no transition segment of material 208, as the material simply terminates as shown in fig. 10C. While the structures of FIGS. 10A/10B and 10C/10D differ, both designs utilize a very gradual basis to create an axis that transitions from a first material property to a second material property. This division and uniformity is significantly better than can be produced by conventional catheter techniques. One example of a material property is stiffness/softness. For example, the catheter of fig. 10B and 10D may transition from a relatively harder material property, e.g., at 170 of fig. 10C and 190 of fig. 10D, to a softer material property, e.g., at 180 of fig. 10B and 198 of fig. 10D. The transition regions (e.g., 172-178 of fig. 10B and 192-196 of fig. 10D) can be tailored by the choice of polymer, transition length, etc., to create a transition that is not at all found in current commercially available catheters. It should also be noted that the lengths of the regions 170 and 190 and 198 (as well as the lengths throughout this disclosure) are intended to convey the principles of the present design. These lengths are not required to be the same, nor are they required to be proportional, unless otherwise required.

It is apparent that the length of each segment shown in fig. 10A and 10C is for illustrative purposes only. In addition, any number of polymer strands may be used with any number of polymers. Further, note that in fig. 10A, the material segments may all be considered as separate elements 204 of the same material. Thus, region 170 includes a material segment that gradually changes in width to region 172, etc. The change in width may be stepwise or incremental, as shown. Alternatively, the change may be tapered such that the change in width is continuous, as shown by the tapered region of the end of material 208 in FIG. 10C.

Fig. 11A illustrates a graph of bending stiffness versus shaft position to aid in understanding the ability of the catheter of the present disclosure to produce a significantly improved transition region over currently available catheters. Fig. 11A shows the results of a test in which the force to move the catheter a given distance is measured, commonly referred to as a 3-point bend test. The catheter is supported at two points so that the gap between the two points will deflect at a given distance. The force required to produce this deflection is measured and plotted to correspond to the distance from the distal end of the catheter. For example, the left side of the figure shows the amount of force required to move a catheter segment at a point closest to the distal end of the catheter (i.e., the distal end). The right side of the force diagram shows the amount of force required to move the catheter section at the point closest to the proximal end of the catheter. Three catheters tested in this manner included a catheter 300 constructed according to the present disclosure, a commercially available catheter 302 manufactured by Medtronic (fact 071) and a commercially available catheter 304 manufactured by Penumbra (ACE 068). The figure shows that the improved catheter 300 has a gradually increasing bending stiffness without a sudden or irregular increase in bending stiffness. In contrast, the graphical data for bending stiffness of Medtronic catheter 302 shows two distinct regions 306 of abrupt change in properties. The graphical data for the bending stiffness of Penumbra catheter 304 shows three distinct, abrupt regions 306.

Fig. 11B shows a catheter segment constructed in accordance with the present disclosure, wherein the catheter segment is held in a position similar to the position of the catheter shown in fig. 1D. However, the modified catheter 310 is constructed in accordance with the present disclosure such that the materials are actively selected to provide the desired properties and characteristics of the catheter 310 over the various longitudinal regions 312, 314, 316, and 318, thereby avoiding any abrupt change regions that would otherwise result in irregular bending. Fig. 11B shows only one example of a catheter 310 using materials 134, 206, 208, and 210. It is apparent that any number of combinations, as described herein, are within the scope of the present disclosure. As shown, longitudinal region 312 includes three sections of material of materials 134, 206, and 210. Longitudinal region 314 includes two material segments of materials 206 and 210. Longitudinal segment 316 includes three segments of material 206, 208, and 210. The segment also shows a material segment of varying width such that material/material segment 206 decreases in thickness and material/material segment 208 increases in a direction toward longitudinal segment 318. Longitudinal segment 318 includes two segments of material 208 and 210. The end result of the configuration of catheter 310 is that longitudinal segments 312 and 314 include significantly different structural characteristics than longitudinal segment 318, but the change is gradual enough to avoid significant discontinuities in bending stiffness.

Fig. 12A-12D are grayscale images of exemplary conduit structures according to the present disclosure. Fig. 12A shows 3 different conduit segments 320, 322, and 324, each having a different helical pitch angle (i.e., the angle that the material segments 134, 132 form with the conduit axis). The conduit 320 exhibits a near radial angle (meaning that the angle is nearly perpendicular to the axis). The structure of the catheter section comprises two strands: one strand 134 of material and one strand 132 of material. The conduit 322 shows a medium pitch angle. The structure of the catheter section comprises 4 strands: one strand 134, one strand 132, one strand 134, and one strand 132. Conduit 324 exhibits an increased pitch angle relative to conduit 320 or 322. The structure of the catheter section comprises 6 strands: one strand 134 and one strand 132 are repeated three times. A greater number of strands are used in the construction process so that the pitch angle can be increased more.

Fig. 12B shows another grayscale image of another variation of a constructed catheter segment having two segments of material composed of the same material on both sides of a segment of material having flexible material 134, with segment of material 130 having a greater width. This configuration may include a "shock absorber" if material 132 is a harder material. Fig. 12C and 12D illustrate a catheter having a contoured outer surface constructed in accordance with the present invention. Fig. 12C shows a grayscale image of another example of a constructed catheter segment, which is made in a manner similar to the structure shown in fig. 3J. In this variation, the height of material 132 is greater than the height of adjacent material 134, and the width of material 132 is less than adjacent material 134. These materials, although different in height, can be fused together to form a polymer layer. Fig. 12D shows another catheter in which section of material 134 has a diameter that is larger than the diameters of adjacent materials 132 and 130. In another variation, the undulating surface may be formed during the fusing process using one or more materials (e.g., as depicted in fig. 3A), with non-fusible material (e.g., high melting temperature polymers such as PTFE, metal alloys, etc.) present on top of the strands such that the non-fusible material is removed leaving voids in the finished polymer layer.

Fig. 12E and 12F show a variation of the conduit 330 and 348, the conduit 330 and 348 may be incorporated into a catheter or used as a tube device without a catheter structure. Fig. 12E and 12F illustrate two material segments 230, 232, which may include any variety of materials. In one example, fig. 12E shows segment 230 embedded within segment 232, segment 230 comprising a hard 72D durometer band (used as a torque coil), and segment 232 comprising a softer 60A durometer band. By increasing the number of material segments per unit, the pitch (i.e., separation) of material 230 increases from 330 to 340. That is, conduit 330 has a single material segment 230 with material segment 232. Instead, structure 340 is formed from a structure that includes a plurality of material strands 230 and a plurality of material strands 232.

Fig. 12F shows a picture of four conduits 342, 344, 346, and 348, where the angles of material segments 230 and 232 vary within each tube. In each of these cells, the pitch (i.e., separation) of the white 72D coils of material segments 230 is constant (i.e., the width of material segments 232 between material segments 230 is the same dimension in each cell). However, the angle of material segment 230 varies in each unit. For example, tube 342 illustrates the angle of material segment 230 that is most radial (i.e., extends radially from the tube), while bottom tube 348 includes the most axial or linear material segment 230. The tube 342 comprises three strands: one strand 230 and two strands 232 to create material segments 230 and 232. Tube 344 is made up of 6 strands: 1 230+2 232+1 230+2 232. Tube 346 is comprised of nine strands and tube 346 is comprised of 12 strands, using the same arrangement.

Fig. 13A and 13B depict another feature of a catheter structure in which multiple strands (similar polymers or different polymers) are joined together as described above. However, in these variations, various discrete materials (i.e., polymers, metals, composites, alloys, etc.) may be patterned on the binder strand 130. In fig. 11A, the polymer is patterned into the illustrated shape 214. The base strand 130 may be removed or the polymer 214 may be placed on top of the base strand. Likewise, a plurality of polymers 214 and 216 may be located on the base strand 130 of polymer. In an optional variation, the base polymer strands 130 may be removed such that the patterned polymer 214 or 216 may be located in the spaces left by the removed base strands 130. The finished assembly 130 may be manufactured as a tube structure to be incorporated into a catheter or other medical device shaft.

Fig. 14A-14C illustrate another variation of constructing a composite polymeric tube 294 having multiple material segments in accordance with the present disclosure. As shown in fig. 14A, the initial structure may include a conventional polymeric tube 290 with one or more strands 292 wound around the tube 290. The tube 290 and the strands 292 are then heat fused together to create a composite polymeric layer 294, wherein the strands 292 become at least partially embedded within the tube 290 such that the polymeric layer 294 includes a first section of material comprising the material 290 of the tube and a second section of material comprising the material 292 of the strands. Obviously, any number of variations of the strands (as described above) may be embedded in the tube. Further, the outer diameter of the polymer layer 294 may include a wave shape. Fig. 14C shows a polymer tube 294 with a portion removed to protrude the cross-section of the polymer layer. In a further variation, the structure of fig. 14A-14C may have a composite polymer tube with multiple material segments configured as described herein in place of the conventional polymer tube 290.

Fig. 15A shows a partial view of a patient's anatomy to demonstrate one feature of the catheter 100 of the present disclosure. Fig. 15A shows a catheter 100 inserted using a radial artery interventional procedure. It is apparent that the conduit structures (as well as the polymer layers) described herein may be incorporated into any device where it is desirable to select materials for specific performance characteristics. Radial artery interventional procedures are becoming increasingly desirable as an entry portal for interventional procedures. Radial artery intervention is the primary mode of cardiac surgery and is increasingly common in neurovascular surgery. However, acute bends present considerable challenges to conventional catheters, especially when attempting to access neurovasculature. The catheter structures described herein are well suited to address the sharp anatomical challenges faced by conventional catheters.

Fig. 15A shows catheter 100 of the present disclosure advanced into radial artery 50 and passed to the right subclavian artery 51 and into the internal carotid artery 53 and ultimately to the neurovascular vessel 60. The catheter 100 shown in fig. 15A includes regions of diverse material segments as described above. However, this variation of the catheter 100 includes a mixing region 220, which mixing region 220 allows for multiple catheter performance characteristics in that region. This configuration not only allows travel through tortuous bends, but does not suffer from the same drawbacks as a catheter that is simply constructed of a soft polymer. The present disclosure contemplates a conduit having any number of mixing regions with any arrangement of material properties.

Fig. 15B shows the region from fig. 15A and shows the acute bend between the right subclavian artery 51 and the right internal carotid artery 53. For the purpose of illustrating this bend, the catheter is removed from fig. 15B. Conventional catheters experience problems when passing through such acute bends because harder/stronger polymers have difficulty navigating through tortuous turns in the anatomy. Softer polymers are able to pass through such acute bends, but the softer segments do not transmit sufficient thrust and torque to the bend and the catheter region distal to the soft polymer.

Fig. 15C shows an enlarged view of a portion of the catheter 100 that is passed through the acute bend between the right subclavian artery 51 and the right internal carotid artery 53. The catheter 100 is designed such that the mixing section 220 is positioned (or of sufficient length) such that the mixing section 220 is within the bend when the distal end of the catheter 100 is at or near its intended target. Fig. 15C shows catheter 100 having multiple material segments 134, 206, etc. However, in this variation, the mixing segment 220 comprises a stiffer material segment 210 and allows for torque and force transfer by the catheter 100. Hybrid segment 220 may also include one or more discrete segments of material 208 that provide desired material properties that are different from base material segment 210. In this example, the discrete segments of material 208 comprise a flexible material. This configuration allows the catheter to bend acutely due to the discrete sections 208 of flexible material. At the same time, the harder durometer base segment 210 transmits the thrust and torque to the distal region of the catheter.

FIG. 15D illustrates a number of non-exhaustive design configurations that produce a blending region as shown in FIGS. 15A and 15C. The blended area of the conduit/production tubing is formed from multiple materials 130 joined together, wherein the base material 210 is interrupted by discrete segments of the second material 208, the second material 208 having different properties than the base. For example, in one variation of this design, material 210 may comprise a stiffer/stiffer material or polymer, while material 208 comprises a pliable/soft material or polymer. Obviously, any material property other than hard/soft material may be selected and configured into the mixing region.

Note that the polymer strands disclosed herein may extend in a helical fashion around the inner braid/coil or support structure. In a further variation, the polymer strands may be aligned in a longitudinal manner with the axis of the catheter and wrapped around the support structure to form the catheter segment. Any number of manufacturing methods may be used to produce the catheter structures of the present disclosure. For example, the strands may be directly wound onto the liner/braid structure and then fused together to form the catheter structure; 2) the strands may be wound around a tube and fused, and then transferred to the remaining components to create a catheter structure; and/or 3) the strands can be manufactured into a flat configuration (or fused together, extruded, molded or otherwise formed) and then the tape assembly wrapped around and fused to the liner/braid. It should be understood that any manufacturing process is within the scope of the present disclosure, and should not limit any claimed structure to any claim related to composite polymer tube or conduit structures.

As to other details of the invention, the materials and fabrication techniques employed may be within the level of those skilled in the relevant art. The same may apply for the method-based aspects of the invention, in terms of additional acts that are commonly or logically employed. Furthermore, while the invention has been described with reference to several examples, optionally incorporating various features, the invention is not limited to what has been described or shown as envisioned with respect to each variation of the invention.

Various changes may be made to the invention described and equivalents may be substituted (whether referred to herein or not for the sake of brevity) without departing from the true spirit and scope of the invention. Furthermore, any optional feature of the inventive variations may be set forth and claimed independently or in combination with any one or more of the features described herein. Thus, the present invention contemplates combinations of aspects of the embodiments or the embodiments themselves, where possible. Reference to a single item includes the possibility that a plurality of the same item exists. More specifically, as used herein and in the appended claims, the singular forms "a," "and," "said," and "the" include plural references unless the context clearly dictates otherwise.

It is important to note that aspects of the various described embodiments, or the embodiments themselves, may be combined where possible. All such combinations are intended to fall within the scope of the present disclosure.

Claims (93)

1. A catheter tubing comprising:

a tubular outer layer extending along an axial length of the tubular body;

the tubular body comprising a plurality of segments of material extending helically along the axial length to form a wall of the tubular body, wherein each segment of material is joined to an adjacent segment of material to form the wall;

wherein the plurality of material segments includes at least a first material segment and a second material segment, the first material segment including a first structural property and the second material segment including a second structural property, wherein the first structural property is different than the second structural property; and is

Wherein along a transition region of the tubular body, a width of the first section of material increases and a width of the second section of material decreases, resulting in a change in a structural property of the transition region along the transition region.

2. The catheter tubing of claim 1 further comprising a liner within the tubular outer layer, and a reinforcing structure external to the liner and within the tubular outer layer.

3. The conduit tube of claim 1, wherein the width of the first section of material and the width of the second section of material vary along the first transition region.

4. The catheter tube of claim 1, wherein the tubular outer layer includes a proximal longitudinal region proximal to the first transition region, wherein the proximal longitudinal region is formed entirely of the first section of material.

5. The catheter tubing of claim 1, wherein the third section of material extends over a majority of the axial length of the catheter tubular body.

6. The catheter tubing of claim 1, wherein at least in a first section of the wall of the tubular body, the first section of material has a width greater than a width of the second material.

7. The catheter tubing of claim 1 wherein the end of the second section of material is tapered.

8. The catheter tubing of claim 1, wherein the helical direction of the first and second sections of material comprises a right-hand wind.

9. The conduit tube of claim 1, wherein the helical direction of the first and second segments of material comprises left-handed coiling.

10. The catheter tubing of claim 1, wherein at least one of the material segments comprises a non-fusible material.

11. A catheter tube comprising:

an outer tubular body having a first section and a second section, each of the first and second sections extending along an axial length of the tubular body;

wherein the outer tubular body comprises a plurality of segments of material extending helically along the axial length, wherein each segment of material is sealingly joined to an adjacent segment of material to form a composite wall of the outer tubular body that surrounds a lumen extending along the axial length;

wherein in the first section, the plurality of sections of material includes at least a first section of material and a second section of material forming the composite wall, the first section of material including a first structural property and the second section of material including a second structural property, wherein the first structural property is different from the second structural property; and

a third section of material having a third structural attribute, wherein the third section of material is joined to an end of the first section of material at the second section such that the third section of material replaces the first section of material in the second section.

12. The catheter tubing of claim 11 further comprising a liner within the tubular outer layer, and a reinforcing structure external to the liner and within the tubular outer layer.

13. The conduit tube of claim 11, wherein the width of the first section of material and the width of the second section of material vary along the first transition region.

14. The catheter tube of claim 11, wherein the composite wall includes a proximal longitudinal region proximal to the first transition region, wherein the proximal longitudinal region is formed entirely of the first section of material.

15. The catheter tubing of claim 11, wherein at least one of the plurality of material segments extends over a majority of the axial length of the catheter tubular body.

16. The catheter tubing of claim 11, wherein at least in the first section of the wall of the tubular body, the first section of material has a width greater than the width of the second material.

17. The catheter tubing of claim 11, wherein the end of the second section of material is tapered.

18. The catheter tubing of claim 11, wherein the helical direction of the first and second sections of material comprises a right-hand wind.

19. The conduit tube of claim 11, wherein the helical direction of the first and second segments of material comprises left-handed coiling.

20. The catheter tubing of claim 11, wherein at least one of the material segments comprises a non-fusible material.

21. A catheter tubing comprising:

a tubular body having a first section and a second section, each of the first section and the second section extending along an axial length of the tubular body; and

a plurality of segments of material extending helically along the axial length to form the first segment, wherein each segment of material is sealingly joined to an adjacent segment of material to form a composite wall of the tubular body surrounding a lumen extending along the axial length;

wherein each of the plurality of material segments comprises a structural property, respectively, and wherein the structural properties of at least two material segments are different;

wherein the first segment comprises a first sequence of material segments and wherein the second segment comprises a second sequence of material segments such that material segments in the first sequence are different from material segments in the second sequence resulting in a structural property of the first segment being different from a structural property of the second segment.

22. The catheter tubing of claim 21 further comprising a liner within the tubular outer layer, and a reinforcing structure external to the liner and within the tubular outer layer.

23. The conduit tube of claim 21, wherein the width of the first section of material and the width of the second section of material vary along a first transition region.

24. The catheter tube of claim 21, wherein the composite wall includes a proximal longitudinal region proximal to the first transition region, wherein the proximal longitudinal region is formed entirely of the first section of material.

25. The catheter tube of claim 21, wherein at least one of the plurality of material segments extends over a majority of the axial length of the catheter tubular body.

26. The catheter tubing of claim 21, wherein at least in the first section of the wall of the tubular body, the first section of material has a width greater than the width of the second material.

27. The catheter tubing of claim 21 wherein the end of the second section of material is tapered.

28. The catheter tubing of claim 21, wherein the helical direction of the first and second sections of material comprises a right-hand wind.

29. The conduit tube of claim 21, wherein the helical direction of the first and second segments of material comprises left-handed coiling.

30. The catheter tubing of claim 21, wherein at least one of the material segments comprises a non-fusible material.

31. A catheter structure comprising:

a catheter shaft having an axial length, the catheter shaft including a tubular outer layer including a plurality of segments of material, each segment of material having a respective width measured along the axial length, the plurality of segments of material extending in a helical direction along the axial length to form a wall of the tubular outer layer, the tubular outer layer having a first longitudinal region, a second longitudinal region, and a transition region between the first longitudinal region and the second longitudinal region;

wherein at the first longitudinal region, the plurality of material segments includes a first material segment and a second material segment, wherein a structural property of the first material segment is different than a structural property of the second material segment such that the first longitudinal region has a first structural characteristic;

wherein at the transition region, the second section of material terminates at an end and a third section of material is joined to the end of the second section of material, wherein a structural property of the second section of material is different than a structural property of the third section of material; and is

Wherein the first section of material and the third section of material extend helically from the transition region to the second longitudinal region such that the structural properties of the second longitudinal region are different from the structural properties of the second longitudinal region.

32. The catheter structure of claim 31, wherein the catheter shaft further includes a liner and a reinforcing structure external to the liner, wherein the tubular outer layer extends over the reinforcing structure and the liner.

33. The catheter structure of claim 31, wherein the width of the first material and the width of the second material vary along the first longitudinal region.

34. The catheter structure of claim 31, wherein the width of the first material and the width of the second material vary inversely along the first longitudinal region such that as the width of the first material increases or decreases, the width of the second material decreases or increases, respectively.

35. The catheter structure of claim 31, wherein the tubular outer layer includes a proximal longitudinal region proximal to the first longitudinal region, wherein the proximal longitudinal region is formed entirely of the first section of material.

36. The catheter structure of claim 31, wherein the tubular outer layer includes a distal longitudinal region distal to the first longitudinal region, wherein the distal longitudinal region is formed entirely of the second section of material.

37. The catheter structure according to claim 31, wherein the plurality of segments of material further comprises at least a fourth segment of material adjacent the second segment of material.

38. The catheter structure according to claim 37, wherein the tubular outer layer comprises a distal longitudinal region distal to the first longitudinal region, wherein the distal longitudinal region is formed entirely of the fourth section of material.

39. The conduit structure of claim 37, wherein the structural properties of the fourth segment of material are different than both the structural properties of the first segment of material and the structural properties of the second segment of material.

40. The conduit structure of claim 37, wherein the structural properties of the fourth segment of material are the same as the structural properties of the first segment of material.

41. The catheter structure of claim 37, wherein the fourth segment of material extends over an entire axial length of the catheter shaft.

42. The catheter structure of claim 31, wherein the width of the first material is different than the width of the second material at least in a first section of the tubular outer layer.

43. The catheter structure according to claim 31, wherein the plurality of material segments comprises at least three or more distinct material segments, at least in a second segment of the tubular outer layer.

44. The conduit structure of claim 31, wherein the helical direction of the first and second segments of material comprises a right-handed coil.

45. The conduit structure of claim 31, wherein the helical direction of the first and second segments of material comprises left-handed coiling.

46. A catheter structure comprising:

a catheter shaft having a tubular outer layer extending over at least a portion of an axial length of the catheter structure, the tubular outer layer including a plurality of segments of material each having a respective width measured along the axial length, the plurality of segments of material extending in a helical direction along the axial length to form a wall of the tubular outer layer, the tubular outer layer having a first longitudinal region, a second longitudinal region; and is

Wherein at the first longitudinal region, the plurality of material segments includes a first material segment located at a first longitudinal region having a first structural characteristic;

wherein at least a portion of the first section of material terminates at an end at the second longitudinal region and a second section of material is joined to the end of the first section of material, wherein a structural property of the first section of material is different than a structural property of the second section of material such that the second longitudinal region has a second structural characteristic that is different than the first structural characteristic.

47. The catheter tube of claim 46, wherein the catheter shaft further includes a reinforcing structure within the tubular outer layer and a liner inside the reinforcing structure.

48. The conduit tube of claim 46, further comprising a third section of material extending adjacent the first section of material in the first longitudinal region, wherein a width of the first section of material and a width of the third section of material vary along a first transition region.

49. The catheter tubing of claim 46, wherein the wall includes a proximal longitudinal region proximal to the first transition region, wherein the proximal longitudinal region is formed entirely of the first section of material.

50. The catheter tubing of claim 46, wherein at least one of the plurality of material segments extends over a majority of an axial length of the tubular outer layer.

51. The catheter tubing of claim 46, wherein at least in a first section of the tubular outer layer, the first section of material has a width greater than a width of the third section of material.

52. The catheter tubing of claim 46, wherein the end of the second section of material is tapered.

53. The catheter tubing of claim 46, wherein the helical direction of the first section of material comprises a right-hand wind.

54. The conduit tube of claim 46, wherein the helical direction of the first section of material comprises left-handed coiling.

55. The catheter tubing of claim 46, wherein at least one of the material segments comprises a non-fusible material.

56. A catheter structure comprising:

a tubular outer layer comprising a plurality of segments of material, each segment of material having a respective width measured along an axial length, the plurality of segments of material extending in a helical direction along the axial length to form a continuous wall of the tubular outer layer; and is

Wherein the plurality of material segments includes a first material segment and a second material segment adjacent the first material segment, wherein a structural property of the first material segment is different than a structural property of the second material segment.

57. The catheter structure of claim 56, wherein the tubular outer layer is an outer layer of a catheter shaft having an inner liner and a reinforcing structure located inside the tubular outer layer.

58. The catheter structure of claim 56, wherein the tubular outer layer includes a longitudinal transition region in which the width of the first section of material and the width of the second section of material both vary along the first longitudinal region, resulting in a change in structural properties over the first transition region.

59. The conduit structure of claim 56, wherein a width of the first section of material and a width of the second section of material vary along the first transition region.

60. The conduit structure of claim 56, wherein the width of the first section of material and the width of the second section of material vary inversely along the first transition region such that as the width of the first section of material increases or decreases, the width of the second section of material decreases or increases, respectively.

61. The catheter structure of claim 56, wherein the tubular outer layer includes a proximal longitudinal region proximal to the first transition region, wherein the proximal longitudinal region is formed entirely of the first section of material.

62. The catheter structure of claim 56, wherein the tubular outer layer includes a distal longitudinal region distal to the first transition region, wherein the distal longitudinal region is formed entirely of the second section of material.

63. The conduit structure of claim 56, wherein the plurality of segments of material further comprises at least a third segment of material adjacent the second segment of material.

64. The catheter structure of claim 63, wherein the tubular outer layer includes a distal longitudinal region distal to the first transition region, wherein all of the material segments of the plurality of material segments in the distal longitudinal region include the third material segment.

65. The catheter structure according to claim 63, wherein the structural properties of the third section of material are different from both the structural properties of the first section of material and the structural properties of the second section of material.

66. The catheter structure according to claim 63, wherein the structural properties of the third section of material are the same as the structural properties of the first section of material.

67. The catheter structure of claim 63, wherein the third segment of material extends over a majority of an axial length of the catheter shaft.

68. The catheter structure of claim 56, wherein the width of the first material is greater than the width of the second material at least in a first section of the tubular outer layer.

69. The catheter structure of claim 56, wherein the plurality of material segments comprises at least four or more distinct material segments, at least in a second segment of the tubular outer layer.

70. The catheter structure of claim 56, wherein:

the tubular outer layer further comprising a second longitudinal region, a third longitudinal region, and a transition region between the second longitudinal region and the third longitudinal region;

wherein the second longitudinal region includes the first section of material and the second section of material defining structural characteristics of the second longitudinal region;

wherein at the transition region, the second section of material has an end and a third section of material is joined to the end of the second section of material, wherein a structural property of the second section of material is different than a structural property of the third section of material; and is

Wherein the first section of material and the third section of material extend helically from the transition region to the third longitudinal region such that the structural properties of the third longitudinal region are different from the structural properties of the second longitudinal region.

71. The conduit structure of claim 70, wherein an end of the second section of material is tapered.

72. The conduit structure of claim 70, wherein the initial width of the first material is greater than the initial width of the second segment of material.

73. The conduit structure of claim 56, wherein the helical direction of the first and second segments of material comprises a right-hand wind.

74. The conduit structure of claim 56, wherein the helical direction of the first and second segments of material comprises left-handed coiling.

75. The catheter structure according to claim 56, wherein at least one of the material segments comprises a non-fusible material.

76. A catheter structure comprising:

a catheter shaft having an axial length, the catheter shaft including a liner, a reinforcing structure external to the liner, and a tubular outer layer extending over the reinforcing structure;

the tubular outer layer comprising a plurality of segments of material, each segment of material having a respective width measured along the axial length, the plurality of segments of material extending in a helical direction along the axial length to form a continuous wall of the tubular outer layer;

wherein the plurality of material segments includes a first material segment, a second material segment, and a third material segment, wherein structural properties of each of the first material segment, the second material segment, and the third material segment are different; and is

The tubular outer layer has a first transition region, wherein a width of at least one of the first, second, or third sections of material varies across the first transition region, resulting in a change in a structural property of the first transition section.

77. The conduit structure of claim 76, wherein the width of the first material and the width of the second material vary continuously along the first transition region.

78. The conduit structure of claim 76, wherein the width of the first material and the width of the second material vary inversely along the first transition region such that as the width of the first material increases or decreases, the width of the second material decreases or increases, respectively.

79. The catheter structure of claim 76, wherein the tubular outer layer includes a proximal longitudinal region proximal to the first transition region, wherein the proximal longitudinal region is formed entirely of the first section of material.

80. The catheter structure of claim 76, wherein the tubular outer layer includes a distal longitudinal region distal to the first transition region, wherein the distal longitudinal region is formed entirely of the second section of material.

81. The catheter structure of claim 76, wherein in at least one section of the tubular outer layer, the width of the first material is greater than the width of the second material.

82. The catheter structure of claim 76, wherein:

the tubular outer layer further comprising a second longitudinal region, a third longitudinal region, and a transition region between the second longitudinal region and the third longitudinal region;

wherein the second longitudinal region includes the first section of material and the second section of material defining a structural characteristic of the second longitudinal region;

wherein at the transition region, the second section of material has an end and a fourth section of material is joined to the end of the second section of material, wherein a structural property of the second section of material is different than a structural property of the fourth section of material; and is

Wherein the first and fourth sections of material extend helically from the transition region to the third longitudinal region such that the structural properties of the third longitudinal region are different from the structural properties of the second longitudinal region.

83. The conduit structure of claim 82, wherein an end of the second section of material is tapered.

84. The conduit structure of claim 82, wherein the initial width of the first material is greater than the initial width of the second segment of material.

85. The conduit structure of claim 82, wherein the helical direction of the first and second segments of material comprises a right-hand wind.

86. The conduit structure of claim 82, wherein the helical direction of the first and second segments of material comprises left-handed coiling.

87. A medical tubing comprising:

a tubular layer comprising a plurality of segments of material, each segment of material having a respective width measured along an axial length, the plurality of segments of material extending in a helical direction along the axial length to form a continuous wall of a tubular outer layer;

wherein the plurality of segments of material includes a first segment of material and a second segment of material adjacent the first segment of material, wherein a structural property of the first segment of material is different than a structural property of the second segment of material; and

a first longitudinal region of the tubular outer layer, wherein a width of the first material and a width of the second material both vary along the first longitudinal region resulting in a variation of a structural property across the first longitudinal region.

88. A medical tubing comprising:

a tubular outer layer comprising a plurality of segments of material, each segment of material having a respective width measured along an axial length, the plurality of segments of material extending in a helical direction along the axial length to form a continuous wall of the tubular outer layer;

wherein the plurality of material segments includes a first material segment, a second material segment, and a third material segment, wherein structural properties of each of the first material segment, the second material segment, and the third material segment are different; and is

The tubular outer layer has a first longitudinal area, wherein a width of at least one of the first, second, or third sections of material varies over the first longitudinal area resulting in a change in a structural property of the first longitudinal section.

89. A medical tubing comprising:

a catheter shaft having an axial length, the catheter shaft including a liner, a reinforcing structure located outside the liner, and a tubular outer layer extending over the reinforcing structure;

the tubular outer layer comprising a plurality of segments of material, each segment of material having a respective width measured along the axial length, the plurality of segments of material extending in a helical direction along the axial length to form a wall of the tubular outer layer, the tubular outer layer having a first longitudinal region, a second longitudinal region, and a transition region between the first longitudinal region and the second longitudinal region;

wherein at the first longitudinal region, the plurality of material segments includes a first material segment and a second material segment, wherein a structural property of the first material segment is different than a structural property of the second material segment, resulting in the first longitudinal region having a first structural characteristic;

wherein at the transition region, the second section of material terminates at an end and a third section of material is joined to the end of the second section of material, wherein a structural property of the second section of material is different than a structural property of the third section of material; and is

Wherein the first section of material and the third section of material extend helically from the transition region to the second longitudinal region resulting in a structural characteristic of the second longitudinal region that is different from a structural characteristic of the second longitudinal region.

90. A method of forming a polymeric tube, the method comprising:

winding a plurality of polymeric strands into a helical configuration forming a polymeric tube, wherein at least two of the polymeric strands comprise different structural attributes;

wherein in a first section of the polymer tube, the plurality of polymer strands form a first sequence;

changing the sequence of the polymer strands to form a second sequence in a second section of the polymer tube; and

fusing each polymer strand to an adjacent polymer strand to form a continuous wall in the polymer tube, wherein the continuous wall defines a lumen therethrough, and wherein the structural properties of the first segment differ from the structural properties of the second segment due to differences in the first and second sequences.

91. A catheter, comprising:

a liner;

an outer layer comprising a plurality of polymeric strands wound into a helical configuration, wherein at least two of the polymeric strands comprise different structural attributes;

wherein in a first section of the outer layer, the plurality of polymer strands form a first sequence;

wherein in a second section of the polymer tube, the polymer strands form a second sequence; and is

Wherein each polymer strand is fused or joined with an adjacent polymer strand such that the plurality of polymer strands form a continuous wall defining a lumen through the polymer tube, and wherein the structural properties of the first segment differ from the structural properties of the second segment due to differences in the first and second sequences.

92. A catheter, comprising:

a liner;

an outer layer comprising a first polymeric material having a tubular shape, at least a second polymeric strand wrapped in a helical configuration around the tubular shape and fused into the first polymeric material such that at least a portion of a wall of the tubular shape comprises the first polymeric material and the second polymeric material, wherein the first polymeric material and the second polymeric material comprise different structural attributes;

wherein in a first section of the outer layer, the first and second polymeric materials form a first pattern;

wherein in a first section of the outer layer, the first and second polymeric materials form a first pattern; and is

Wherein each polymeric strand is fused or joined with an adjacent polymeric strand such that the plurality of polymeric strands form a continuous wall defining a lumen through the polymeric tube, and wherein a structural property of the first segment differs from a structural property of the second segment due to a difference in the first sequence and the second sequence.

93. The catheter or catheter structure of any of the preceding claims, wherein the tubular outer layer comprises a plurality of segments of material, each segment of material having a respective width measured along the axial length, the plurality of segments of material extending in a helical direction along the axial length to form a continuous wall of the tubular outer layer.