High-pressure balloons and methods for making them

Abstract

Flexible high-pressure angioplasty balloons are disclosed herein which utilize an inflatable balloon positioned upon the catheter and a supporting structure secured over or along the catheter at a first location proximal to the balloon and at a second location distal to the balloon. Inflation of the balloon reconfigures the supporting structure to urge the first location and the second location towards one another thereby inhibiting longitudinal elongation of the balloon relative to the catheter. The supporting structure may surround, support, or otherwise extend over the entire length of the balloon and allows for the balloon to retain increased flexibility which enables the balloon to bend or curve even at relatively high inflation pressures.

Description

HIGH-PRESSURE BALLOONS AND METHODS FOR MAKING THEMRELATED APPLICATION DATA

[0001] The present application claims benefit of co-pending U.S. provisional application Serial No. 63 / 723,552, filed November 21, 2024, and is a continuation-in-part of co-pending U.S. application Serial No. 18 / 882,659, filed September 11, 2024, which is a continuation of International Application No. PCT / US2023 / 015051, filed March 12, 2023, which claims benefit of U.S. provisional application Serial No. 63 / 319,309, filed March 12, 2022, the entire disclosures of which are expressly incorporated by reference herein.TECHNICAL FIELD

[0002] The present application relates to balloon catheters and to methods for making and using such balloon catheters. More particularly, the present application relates to angioplasty catheters including balloons that maintain their flexibility and / or shape when inflated and to methods for making and using such catheters.BACKGROUND

[0003] Conventional angioplasty balloons are typically constructed of low- compliance materials that tolerate high inflation pressures and attain uniform predictable diameters in vivo even when portions of the surrounding artery are narrow and calcified. The typical balloon has a cylindrical section of uniform diameter between conical ends and a central catheter extending along the longitudinal axis of the balloon. When inflated at high-pressures, the walls of the balloon are placed into tension and the balloon becomes stiff and biased into a straightened configuration. Such balloons impose this straightened cylindrical configuration on any balloon-expanded stent that is crimped or otherwise loaded upon the balloon for expansion.

[0004] The presence of a straight stent in a curved artery (e.g., coronary, renal, femoral arteries, and the like) imparts stresses and strains into the stent structure, the artery, or both, especially when the artery is mobile. The resulting repetitive micro-trauma may incite inflammation, hyperplasia and recurrent narrowing, often to the point of catastrophic flow limitation.

[0005] Previous efforts to imbue an angioplasty balloon with flexibility or conformability have employed segmentation, helical shape, and compliant balloonmaterials. Segmented balloons take a variety of forms depending on the degree of segmentation. For instance, previous devices have included spherical balloons strung out along a central catheter having narrow intervening segments that are easily bent. However, such balloons are ill-suited to stent delivery because they impose a bumpy segmented shape upon the stent. If a segmented balloon is inflated enough to eliminate inter-segment gaps and deliver a more completely expanded stent, adjacent segments interfere with one another hindering much of the flexibility.

[0006] Other suggested balloons have included adjacent segments that are separated by grooves in an otherwise continuous balloon. These localized “hinge-points” do little to enhance differential lengthening and the effect on balloon flexibility is therefore modest at best. Other balloons have deep grooves that separate bulges in the balloon profile but these too have a modest effect on flexibility.

[0007] Helical balloons have also been used to increase flexibility where the winding of the balloon disrupts longitudinal continuity so that adjacent windings on the outer aspect of a bend in the balloon can separate while those on the inner aspect remain in close apposition. The resulting potential for differential lengthening imparts some flexibility. In addition, helical balloons benefit from multi-lumen construction. Each of the component balloons is narrower and therefore more flexible than the resulting helix.However, such helical balloons suffer many of the same limitations as segmented balloons. They either deliver incompletely expanded stents or become less flexible when overinflated to eliminate gaps. Moreover, even when the balloon is straight, its components have tight bends that, unless tightly constrained, straighten on high-pressure inflation, whereupon the helical balloon may tear itself apart. A non-compliant, tightly-wound, helical balloon may potentially tear itself apart upon high-pressure inflation. A less tightly wound helical balloon is more stable but less flexible.

[0008] Balloons that are constructed from compliant materials are more flexible than similar balloons constructed of non-compliant materials. However, compliant balloons cannot withstand the high pressures required for balloon angioplasty because they tend to expand in the direction of least resistance, leaving narrow areas untreated, rupturing the artery in areas of weakness, and / or spreading beyond the intended field of angioplasty. In addition, compliant balloons may be unable to generate sufficient force to initiate stent expansion. Early angioplasty balloons made of compliant materials were subsequentlyreinforced by the application of various braids, meshes, and wraps in an attempt to control balloon shape and dimensions at higher working pressures.

[0009] External braids, wraps, and fabrics of all kinds have also been embedded into the walls of low-compliance balloons to further increase the maximum working pressure. However, the integration of a braid into the low-compliance wall of a high-pressure balloon prevents changes in braid angle. The braid of such a balloon is not free to open and close, or shorten and lengthen, with balloon expansion and contraction. Consequently, the presence of the braid does nothing to shorten the balloon, relieve longitudinally-directed tension, generate redundant folds in its walls, enhance flexibility, or prevent forcible straightening during inflation.

[0010] Further, high pressure inflation of a non-compliant angioplasty balloon applies outwardly directed forces to the inner surface of the balloon. Pressure acting on the mid-portion of the balloon generates force in a trans-axial direction, while pressure on the ends of the balloon generates force in an axial direction. In general, trans-axially directed forces have the desired dilating effect on the surrounding artery. Axially directed forces, on the other hand, have less effect on the midportion of the balloon, and more on the end of the balloon, which stretches and straightens into a substantially cylindrical shape, regardless of the shape of the surrounding artery.

[0011] Accordingly, there exists a need for balloons that, when inflated to high- pressure, remain flexible and / or retain a curved configuration.SUMMARY

[0012] The present application is directed to balloon catheters, and, more particularly, to angioplasty balloon catheters that include non-compliant balloons that maintain flexibility and / or shape when inflated, and to methods for making and using such balloon catheters. The balloon catheters provided herein may also be for other applications, e.g., to deliver and deploy stents or other prostheses within a patient’s vasculature and / or to dilate passages within or outside a patient’s vasculature, e.g., within a patient’s sinuses.

[0013] The patent literature is filled with designs of balloons that are said to avoid forcible straightening while preserving the artery’s non-cylindrical geometry; however, very few achieve clinically relevant degrees of flexibility or conformability.

[0014] One exception are the balloons and catheters disclosed in U.S. Patent No. 9,149,612, by the same inventor as the present application, the entire disclosure of which isexpressly incorporated by reference herein. The balloons disclosed in this patent carry an external braid, which shortens or prevents substantial elongation upon inflation, thereby opposing the lengthening that would otherwise cause the balloon to straighten and stiffen.

[0015] The redundancy generated by balloon expansion may contribute to the necessary length differential between the inner and outer aspects of a curved balloon. Such braids may be capable of supporting single-plane, uniform-curvature bends in the balloon, but may not be able of supporting multi-plane, multi -curvature bends, and may not be able to match localized variations of target artery geometry.

[0016] For the balloon to overcome forcible straightening, each end of the balloon, and the corresponding end of the braid, must be attached co-locally to adjacent segments of the inner or outer shafts of the catheter. Any gap between the ends of the external braid and the corresponding ends of the balloon, may create compressive loading of the intervening catheter, which may consequently kink, potentially obstructing both the inflation lumen and the guide-wire lumen of the catheter. The larger the balloon and the longer the gap between balloon / catheter and braid / catheter attachment sites, the more severe may be the degree of angulation and the associated (potentially catastrophic) failure modes.

[0017] The present application provides improvements to such balloons and catheter devices. In accordance with one example, an inflatable angioplasty balloon may be configured to include a supporting structure, such as a braid, wrap, mesh, and the like, including a plurality of elongate fibers, which is carried by the balloon membrane, e.g., wrapped around or otherwise positioned externally of the balloon membrane. The supporting structure may allow the balloon to retain increased flexibility when inflated such that the balloon is able to curve or retain a curved configuration, even at relatively high inflation pressures. For example, the braid of the supporting structure may be asymmetrical, e.g., such that the fibers of the braid do not pass over and under intersecting fibers in a single over-under pattern.

[0018] In one example, fibers in at least one direction of the braid may be provided in sets, e.g., a pair of adjacent braids that are passed over and under intersecting fibers in the same manner (with the fibers remaining free to slide relative to one another at intersection locations). In one particular pattern, pairs of fibers may be provided adjacent one another in each direction that pass over and under sequential intersecting pairs of fibers.

[0019] In yet another example, fibers may pass over and / or under multiple intersecting fibers to provide an asymmetrical braid pattern. For example, the supportingstructure may include a braid in which fibers passing in a first helical direction pass over two intersecting fibers and the under the next two intersecting fibers, while fibers passing in a second helical direction may pass over and under alternating intersecting fibers. One particular example of such an asymmetrical braid pattern is a herringbone pattern, e.g., a 1 over 2 under 2 pattern. It will be appreciated that many variations of such an asymmetrical pattern may be provided, e.g., in which fibers in one helical direction may pass over (or under) two or more intersecting fibers and then pass under (or over) one or more intersecting fibers uniformly along the length of the balloon, or alternatively, in a nonuniform or other varying manner depending on the desired rigidity characteristics of the resulting balloon catheter.

[0020] One advantage of such asymmetrical braid patterns is that they may provide increased braid stability and / or desired reorientation upon expansion. For example, in the collapsed configuration before balloon expansion, the braid may also provide enhanced flexibility to accommodate bending of the balloon, e.g., during delivery and / or positioning within tortuous anatomy, similar to symmetrical braid patterns. However, once the balloon is expanded, the braid may expand to increase stability of the resulting supporting structure, e.g., to prevent straightening or other shape changes during expansion. For example, with a herringbone or other asymmetrical braid configuration, the expanded braid may have a radial thickness greater than twice the diameter or other cross-section of the individual fibers of the braid.

[0021] Generally, the balloon assembly may include a catheter having a length, an inflatable balloon, e.g., with a substantially cylindrical mid-portion between two substantially conical or otherwise tapered end sections, positioned upon the catheter, e.g., on a distal portion of the catheter, and a supporting structure, e.g., including a plurality of inelastic fibers braided together, secured over or along the catheter at one or more locations, e.g., at a first location proximal to the cylindrical section of the balloon and at a second location distal to the cylindrical section of the balloon such that inflation of the balloon reconfigures the supporting structure to urge the first location and the second location towards one another thereby inhibiting longitudinal elongation of the balloon relative to the catheter.

[0022] During balloon expansion, the increasing balloon diameter may force the fibers of the supporting structure to deviate away from the most direct path between the first and second locations or other balloon attachments. Since the fibers of the supportingstructure have little capacity for stretching, balloon-induced widening of the supporting structure may be accompanied by shortening, which pulls the proximal and distal ends of the balloon towards one another. Hence, as the balloon inflates, tension imparted into these fibers substitutes or offsets the longitudinally-directed tension. Further inflation may even produce one or more small redundant circumferential folds in the balloon. The combination of redundancy and low longitudinally-directed wall tension may make the balloon flexible and / or able to retain a curved configuration, even when fully inflated.

[0023] There are many options when it comes to the choice of polymer for the braid fibers, but few combine the necessary ability for braid material to melt into a folded end of the balloon while retaining sufficient strength to resist the forces encountered during balloon expansion. In one example, to provide such characteristics, the fibers of the braid may be formed from a mixture of polymer types. For example, an admixture of polyethylene naphthalate (“PEN”) fibers may provide the composite braid with strength, and Nylon 6 fibers may provide the composite braid with a source of flux material. In this example, the fibers of the PEN / Nylon 6 braid are commonly used in combination with a standard Nylon balloon.

[0024] In one example, the supporting structure is external to the balloon membrane and freely movable relative to the balloon surface between the fixed ends. A supporting structure configured as a mesh of supporting fibers may bend in much the same way as a braided stent by reorienting its fibers rather than stretching its fibers. Moreover, the supporting fibers may offer little resistance to bending or curving of the balloon because little energy is needed to reorient such a mesh of fibers. Furthermore, increasing the number of fibers in a supporting structure configured as a braid, wrap, or mesh may reduce or eliminate bulging by portions of the balloon in the spaces between the fibers, e.g., by reducing the distance between the fibers and / or by further distributing any loads over the fibers.

[0025] Regardless of the number of fibers used or the configuration of the supporting structure, the supporting structure may be formed from substantially inelastic material (e.g., nylon, Nitinol, Kevlar Vectraon, Spectra, Dacron, Dyneema, Terlon (PBT), Zylon (PBO), Polyimide (PIM), ultra-high molecular weight polyethylene, and the like), shaped into fibers that are suitably flexible to be collapsed into a low-profile configuration when the balloon is deflated, e.g., for stent loading and / or intravascular delivery. Thesupporting structure is also suitably flexible to be reconfigured into its deployed configuration when the balloon is inflated for stent deployment or an angioplasty procedure.

[0026] The pitch or angle between the fibers of the supporting structure and the longitudinal axis of the balloon may vary according to the desired mechanical properties of the specific application. For example, a relatively low pitch - with the fibers initially oriented substantially parallel to the longitudinal axis of the balloon - may minimize resistance to expansion. A relatively high pitch substantially orthogonal to the longitudinal axis may optimize the flexibility of the fully expanded balloon, and / or place a finite upper limit on its diameter. The higher pitch may also increase the ratio of length change to diameter during expansion. The pitch may also vary along the length of a single balloon. For example, a relatively low pitch within the end sections may stabilize their shape and length, while a relatively high pitch in the cylindrical section may afford greater flexibility.

[0027] As the balloon shortens under the action of the supporting structure, a portion of the catheter within the balloon may also be configured to shorten, e.g., to accommodate the balloon shortening. In one example, a supportive braid, wrap, or spring component of the catheter may prevent buckling, prevent collapse of the wire lumen, and / or, via its attachments to the supporting structure, help the balloon resume a low-profile state for removal.

[0028] In accordance with one example, an apparatus is provided for performing a procedure within a patient’s body that includes a tubular member comprising a proximal end, a distal end sized for introduction into a patient’ s body, and a longitudinal axis extending therebetween; a non-compliant balloon carried on the distal end comprising a central region and end regions transitioning from the central region to attachment locations on the distal end, the balloon expandable from a contracted condition to an expanded condition; and a supporting structure comprising a plurality of substantially inelastic fibers braided together and extending helically around an outer surface of the balloon and comprising ends attached to the distal end such that the one or more fibers are movable relative to the central region of the balloon. The fibers may include a first set of fibers formed from polyethylene, e.g., polyethylene naphthalate (“PEN”), providing axial strength to the braid, and a second set of fibers formed from polyamide, e.g., Nylon 6, providing a source of flux material for the braid, which may melt at processing temperatures used during assembly of the device.

[0029] In accordance with another example, a method is provided for performing a medical procedure that includes introducing a distal end of a tubular member into a patient’s body with a non-compliant balloon thereon in a contracted condition and one or more inelastic fibers on the balloon in a low-profile configuration; positioning the balloon within a lesion within a body lumen; and expanding the balloon to an expanded condition, thereby reconfiguring the one or more fibers to shorten the balloon as the balloon expands.

[0030] In accordance with another example, a method is provided for making a catheter that includes providing a tubular member comprising a proximal end and a distal end sized for introduction into a patient’s body; forming a balloon from non-compliant material such that the balloon includes a central cylindrical section expandable to a predetermined size when inflated and end sections for attaching to the distal end of the tubular member; with the balloon in a contracted condition; positioning a plurality of braided fibers around the balloon; and attaching ends of the fibers over the end sections of the balloons. The fibers may have predetermined length such that, upon inflation of the balloon, the fibers apply an axially compressive force to prevent foreshortening or shorten the balloon to enhance flexibility of the fully inflated balloon. In one example, the fibers may be braided around the balloon such that the fibers are free to slide or otherwise move over the outer surface of the balloon, e.g., to accommodate bending the balloon.

[0031] The balloon and braided supporting structure are attached to a catheter shaft or other tubular member. Various glues and heat-mediated methods of attachment have shown moderate success in securing accurate co-located inter-component connections between the braid, the balloon and the inner catheter. In one example, a strong, precise inter-component connection is achieved by the direct application of heat, e.g. through a split clamp, to a precise location on a short segment of the catheter. If, in this example, the required flux material has an external source (such as polyamide 12 or other filler material), the resulting bump in the profile of the device adds to the diameter of the arterial access site. Alternatively, some of the flux material used in the fiber, balloon, and catheter connection is derived from the braid, and the constituent polymer literally melts into the balloon / braid / catheter composite which becomes strong, short and bump free.

[0032] Ideally, the inter-component connections between the ends of the braid, the ends of the balloon, and the catheter shaft are co-located, in which case the order of assembly is unimportant. In practice, however, it may be difficult to connect all three at once, in which case the balloon / braid connections take priority because they are easier toposition accurately. In one approach, the first step is to ensure the precise, secure, colocated connection of balloon neck to braid end, resulting in a balloon / braid module that can be added subsequently to the catheter portion of the device.

[0033] Once the ends of the balloon / braid assembly are attached to respective locations on the tubular member, any further components or procedures may be used to provide a completed catheter. For example, if the balloon / braid assembly is attached to a relatively short segment of the catheter shaft, additional sections of the catheter may be attached to the short segment, e.g., using conventional methods and materials.

[0034] The resulting construction may provide a catheter that includes a reinforced balloon that may be inflated to high pressures with the braid preventing elongation to enhance flexibility of the catheter shaft. Thus, the devices and methods herein may balance the tendency of the high internal pressure within the balloon to push the ends of the balloon away from one another with the high external tension in the fibers of the braid pulling the ends of the braid towards one another. Unless the balloon-catheter and braid-balloon attachments are secure and precisely co-located, compressive loading of the intervening inner catheter may cause off-axis deviation, kinking, component separation and internal herniation with potentially catastrophic consequences for balloon performance. The present methods minimize such risks.

[0035] One exemplary method to achieve the desired stability of component attachment during assembly of the device involves using precisely controlled heat-induced fusion (welding) to attach the ends of the balloon / braid assembly to the catheter. Secure attachment requires sufficient polymer, either from melting the components themselves or from melting an external source of welding material. The mixed function of the PEN / Nylon braid delivers strength through one set of fibers and low-temperature flux through another. A mixed braid may also help to locate the weld site, in real-time, through changes in appearance of differently pigmented sets of braid fiber, which may facilitate visually confirming when the ends are properly attached to the catheter.

[0036] In addition or alternatively, a titanium or tungsten-loaded plastic marker band may be positioned at the apex of the balloon neck, e.g., positioned on an outer aspect of the balloon. Such a band may prevent dilation and / or herniation of the tapered section of the balloon, may enhance identifying the neck of the conical segment of the balloon on fluoroscopy, and / or may provide a reservoir of polymer, e.g., for heat-mediated braid / balloon and balloon / catheter attachment.

[0037] Components are generally added one at a time, in any desired order. However, because the braid lies outside both the catheter and the balloon, mass production may be most easily achieved by adding the braid to a previously assembled balloon, e.g., allowing precise positioning is achieved by first attaching the braid to the balloon, and then attaching the ballon-braid assembly to precisely-identified locations on the catheter.

[0038] In accordance with yet another example, a method is provided for preparing a balloon catheter comprising a tubular member including proximal and distal ends, a non- compliant balloon on the distal end in a contracted condition and a plurality of inelastic fibers on the balloon in a low-profile configuration. The balloon may be inflated to an expanded condition, thereby reconfiguring the fibers to prevent elongate or shorten the balloon as the balloon expands. For example, the fibers may be provided in a braid or mesh over the balloon such that the fibers are free to slide over the outer surface of the balloon, e.g., to accommodate bending of the balloon. Once expanded, the balloon may be bent into a curved shape in the expanded condition, thereby reconfiguring the fibers further to maintain the balloon in the curved shape. For example, the fibers may slide along the outer surface of the balloon to accommodate the curved shape and / or one or more folds may be formed in the balloon. The balloon may then be deflated to the contracted condition, e.g., such that the balloon is biased to the curved shape when subsequently re-inflated.

[0039] In one example, the fibers may migrate over the outer surface of the balloon as the balloon is bent into the curved shape, e.g., such that fibers migrate towards the inside of the curve and / or otherwise reduce tension on the balloon and / or tubular member, which may facilitate the balloon bending without kinking. For example, the fibers may migrate towards the inside of the curve, creating an asymmetrical tension in the fibers that applies a similar asymmetrical force on the balloon to maintain the curved shape, regardless of externally applied bending forces that might otherwise cause the balloon to straighten. Thus, a balloon of this type may exhibit “shape-memory” - once inflated in a curved shape, the balloon may return to substantially the same curved shape when re-inflated, even though the uninflected balloon is straight and flexible. This phenomenon may occur because asymmetrical braid distribution only affects the shape of the balloon when the fibers are tensioned by balloon expansion. When the balloon is in its unexpanded state the braid fibers have little tension and exert little influence on balloon shape. In another example, the braid may be configured to remain substantially stable, e.g., uniformly distributed over the outer surface independent of the shape to which the balloon is directed. Thus, in thisexample, the fibers may slide easily over the outer surface as the balloon changes shape under the action of externally applied forces.

[0040] For example, if the balloon is prepared in preparation for a medical procedure, the distal end of the catheter may be introduced into a patient’s body with the balloon in the contracted condition, and positioned within a lesion or other treatment side within a body lumen. The balloon may then be inflated within the body lumen, whereupon the balloon is biased towards the curved shape within the lesion. For example, the contracted balloon may be positioned within a curved body lumen and oriented such that the curved shape is aligned generally with the curved shape of the body lumen. Thus, when the balloon is inflated, the balloon may expand towards the curved shape, thereby dilating the body lumen while minimizing risk of straightening or otherwise imposed undesired stresses on the walls of the body lumen resulting from straightening forces.

[0041] In accordance with another example, a device is provided for performing procedure within a patient’s body that includes a tubular member comprising a proximal end, a distal end sized for introduction into a patient’ s body, and a longitudinal axis extending therebetween; a non-compliant balloon carried on the distal end comprising a central region and end regions transitioning from the central region to attachment locations on the distal end, the balloon expandable from a contracted condition to an expanded condition; and a supporting structure comprising a plurality of substantially inelastic fibers formed as a braid extending helically around an outer surface of the balloon and comprising opposite ends fixedly attached over the respective attachment locations such that intermediate regions the fibers are movable relative to the central region of the balloon; wherein the fibers are braided in an asymmetrical pattern, e.g., in a 1 over 2 under 2 herringbone pattern.

[0042] In accordance with another example, a device is provided for performing procedure within a patient’s body that includes a tubular member comprising a proximal end, a distal end sized for introduction into a patient’ s body, and a longitudinal axis extending therebetween; a non-compliant balloon carried on the distal end comprising a central region and end regions transitioning from the central region to attachment locations on the distal end, the balloon expandable from a contracted condition to an expanded condition; a supporting structure comprising a plurality of substantially inelastic fibers formed as a braid extending helically around an outer surface of the balloon and comprising opposite ends fixedly attached over the respective attachment locations such thatintermediate regions the fibers are movable relative to the central region of the balloon; and a collar attached over the opposite ends to prevent the attachment locations of the balloons from flaring or otherwise separating from the tubular member.

[0043] In accordance with still another example, a method is provided for making a balloon catheter that includes providing a balloon formed from non-compliant material comprising a central region and end regions attached at spaced-apart locations on a tubular member; providing a tubular braid comprising a plurality of inelastic fibers braided helically between opposite ends of the tubular braid; positioning the tubular braid over the balloon such the opposite ends are positioned over respective end regions of the balloon; applying or positioning flux material over each of the opposite ends of the tubular braid and the end regions; positioning a collar over the flux material on each of the opposite ends of the tubular braid; and heating the flux material to melt or flow the flux material to attach the opposite ends of the tubular braid to the respective end regions.

[0044] Other aspects and features including the need for and use of the present invention will become apparent from consideration of the following description taken in conjunction with the accompanying drawings.BRIEF DESCRIPTION OF THE DRAWINGS

[0045] It will be appreciated that the exemplary apparatus shown in the drawings are not necessarily drawn to scale, with emphasis instead being placed on illustrating the various aspects and features of the illustrated examples. The drawings illustrate examples, in which:

[0046] FIG. 1 shows a side view of an example of a conventional angioplasty balloon positioned upon an elongate catheter.

[0047] FIG. 2 shows a side view of an exemplary device including a balloon positioned on an elongate catheter with a supporting structure including a pair of fibers wound as a braid, wrap, mesh, and the like around the balloon.

[0048] FIG. 2A is a detail showing an example of a symmetrical braid pattern that may be provided in a supporting structure for a balloon catheter, e.g., including fibers in both helical directions passing alternately over and under sequential intersecting fibers of the braid.

[0049] FIG. 2B is a detail showing another example of a symmetrical braid pattern that may be provided in a supporting structure for a balloon catheter, e.g., including fibers inboth helical directions passing over and under every two sequential intersecting fibers of the braid.

[0050] FIG. 2C is a detail showing another example of a braid pattern that includes pairs of fibers adjacent one another in each direction that pass over and under sequential intersecting pairs of fibers.

[0051] FIG. 2D is a detail of another example of a braid pattern including an asymmetrical pattern in which fibers passing in a first helical direction pass sequentially over two intersecting fibers and then under the next two intersecting fibers, while fibers passing in a second helical direction may pass over and under alternating sequential intersecting fibers.

[0052] FIGS. 3A and 3B show side views of an inflated balloon having a supporting structure as it is inflated and bent or curved.

[0053] FIGS. 4 A and 4B show side views of an exemplary angioplasty balloon having an inflated length without any supporting structure on the balloon.

[0054] FIGS. 5A and 5B show side views of an inflated balloon having a supporting structure in its straightened and bent or curved configuration.

[0055] FIG. 6 shows an example of a balloon attached to an underlying catheter shaft by collars on each end of the balloon (with the braided supporting structure omitted for clarity).

[0056] FIG. 7 is a side view of still another example of a balloon catheter in which fibers of a supporting structure frictionally engage the outer surface of the balloon to resist the balloon straightening when inflated in a curved orientation.

[0057] FIG. 7A is a detail showing an exemplary geodesic patterning that may occur from the braid of a supporting structure tensioning upon balloon inflation using the devices wherein, such as the devices shown in FIG. 7.

[0058] FIG. 8 shows another example of a catheter including a supporting structure overlying a non-compliant balloon on a distal end of the catheter.

[0059] FIG. 9 is a photomicrograph showing the ends of braid fibers concentrically distributed and attached around the neck of a balloon, such as that shown in FIG. 13, for secure hemostatic attachment in the presence of high pressure balloon inflation.

[0060] FIGS. 10A and 10B are perspective and side views, respectively, of a collar or cuff that may be provided for attaching ends of a braided supporting structure to an underlying balloon and / or catheter shaft. In the example shown, the collar includes one ormore pockets (three shown extending from one end of the collar) that may facilitate braid material melting into and / or otherwise fusing with the collar and the underlying balloon and / or catheter material.

[0061] FIGS. 11 A and 1 IB are details of one end of a braided supporting structure being attached to an underlying end of a balloon of a balloon catheter, with the balloon collapsed (FIG. 11 A) and expanded (FIG. 1 IB).

[0062] The drawings are not intended to be limiting in any way, and it is contemplated that various examples of the invention may be carried out in a variety of other ways, including those not necessarily depicted in the drawings. The accompanying drawings incorporated in and forming a part of the specification illustrate several aspects of the present invention, and together with the description serve to explain the principles of the invention; it being understood, however, that this invention is not limited to the precise arrangements shown.DETAILED DESCRIPTION

[0063] The following description of certain examples of the invention should not be used to limit the scope of the present invention. Other examples, features, aspects, embodiments, and advantages of the invention will become apparent to those skilled in the art from the following description, which is by way of illustration, one of the best modes contemplated for carrying out the invention. As will be realized, the invention is capable of other different and obvious aspects, all without departing from the invention. Accordingly, the drawings and descriptions should be regarded as illustrative in nature and not restrictive.

[0064] Before the examples are described, it is to be understood that the invention is not limited to particular examples described, as such may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular examples only, and is not intended to be limiting, since the scope of the present invention will be limited only by the appended claims.

[0065] Where a range of values is provided, it is understood that each intervening value, to the tenth of the unit of the lower limit unless the context clearly dictates otherwise, between the upper and lower limits of that range is also specifically disclosed. Each smaller range between any stated value or intervening value in a stated range and any other stated or intervening value in that stated range is encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded in therange, and each range where either, neither or both limits are included in the smaller ranges is also encompassed within the invention, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included in the invention.

[0066] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, some potential and exemplary methods and materials are now described.

[0067] It must be noted that as used herein and in the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a compound” includes a plurality of such compounds and reference to “the polymer” includes reference to one or more polymers and equivalents thereof known to those skilled in the art, and so forth.

[0068] Certain ranges are presented herein with numerical values being preceded by the term “about.” The term “about” is used herein to provide literal support for the exact number that it precedes, as well as a number that is near to or approximately the number that the term precedes. In determining whether a number is near to or approximately a specifically recited number, the near or approximating unrecited number may be a number which, in the context in which it is presented, provides the substantial equivalent of the specifically recited number.

[0069] The term “substantially” is used throughout this document to indicate variations in the thus qualified terms. These variations are variations that do not materially affect the manner in which the invention works and can be due, for example, to uncertainty in manufacturing processes or to small deviations from a nominal value or ideal shape that do not cause significant changes to the invention. Also, the terminology “proximal” and “distal” refers to a position relative to an operator using the present disclosure on a patient. For example, distal elements are closer to an intervention site, e.g., within a patient’s body, and proximal elements are closer to an operator, for example, a doctor or other operator using the devices herein.

[0070] Generally, the devices, apparatus, and methods herein relate to catheters for performing angioplasty and / or other endovascular procedures, e.g., stent delivery, treating arteriovenous fistulae, and / or for otherwise treating body lumens within a patient’s body.The devices, apparatus, and methods herein may also be used during non-vascular procedures, such as vertebroplasty, sinuplasty, and the like. The devices generally include a catheter or other tubular member carrying a balloon that includes a proximal end section and a distal end section (e.g., conically-shaped or otherwise tapered end sections) and having a substantially cylindrical section therebetween. Ends or neck regions of the balloons may be attached to the tubular member at axially spaced-part locations. Alternatively, the device may include inner and outer shafts, e.g., with the inner shaft positioned within a lumen of the outer shaft to provide an annular region between the inner and outer shafts (not shown). A distal end of the inner shaft may extend distally beyond a distal end of the outer shaft, and a distal end or neck region of the balloon may be attached to the inner shaft and a proximal end or neck region may be attached to the outer shaft. Thus, the interior of the balloon may communicate with the annular region, thereby providing an inflation lumen for the device. In one example, the inner and outer shafts may be axially fixed relative to one another such that the distal ends of the inner and outer shafts do not move axially relative to one another within the balloon.

[0071] The balloon also includes a supporting structure such as one or more wires or other fibers provided as a braid, wrap, mesh, and the like, which is wrapped around the balloon membrane. The supporting structure may surround, support, and / or otherwise extend over the entire length of the balloon to provide support yet be free to move relative to the balloon, which may allow the balloon to retain increased flexibility and / or enable the balloon to bend or curve and / or resist straightening from a curved shape even at relatively high inflation pressures. If the balloon includes a high-friction outer surface, the supporting structure may engage the balloon upon inflation, thereby resisting the balloon changing shape from the shape before it is inflated, e.g., a curved or other non-straight shape corresponding to the body lumen where the balloon is deployed.

[0072] During balloon expansion, the increasing balloon diameter may force the fibers of the supporting structure apart from one another, thereby shortening the supporting structure along its longitudinal axis. This shortening of the supporting structure pulls the proximal and distal ends of the balloon towards one another. Hence, as the balloon itself becomes fully inflated, tension imparted into these fibers substitutes or offsets the longitudinally-directed tension in the membrane wall of the cylindrical portion of the balloon. Thus offloaded, the membrane walls of the cylindrical portion of the balloon arefree to lengthen differentially thereby allowing for balloon curvature and / or increased flexibility even when fully inflated.

[0073] Turning to the drawings, FIG. 1 shows an example of an angioplasty balloon 10 positioned upon the catheter 12 without any braid or other external support, which may be directed between a contracted or delivery condition (not shown) and an expanded condition, shown in FIG. 1. In the expanded condition, the balloon 10 may generally include a substantially cylindrical central section 18, and a proximal section 14 and a distal section 16, one or both of which may be conically shaped, tapered, or otherwise transition from the central section 18 to the outer wall of the catheter 12. Each of the respective sections 14, 16 may be attached to the distal end 12b of the catheter 12, e.g., at attachment locations 20, 22 using any number of securement mechanisms, e.g., one or more of bonding with adhesive, fusing, sonic welding, external collars, and the like (not shown). For example, each attachment location 20, 22 may include a relatively narrow neck, e.g., a relatively short uniform diameter section (not shown, see, e.g., FIG. 12), for attaching the balloon 10 to the catheter 12, as described elsewhere herein.

[0074] The membrane of the balloon 10 may generally comprise a low-compliance or non-compliant material. The resulting non-compliant balloon 10 may be capable of withstanding relatively high-pressure inflation. As used herein, “non-compliant” means that the balloon 10 expands to a predetermined expanded shape, e.g., having a substantially uniform diameter along the central section 18, upon initial inflation, e.g., to a threshold pressure. If the pressure is increased beyond the threshold pressure, the size and / or shape of the balloon 10 may remain substantially unchanged, e.g., to allow the balloon 10 to apply the pressure radially outwardly to adjacent body structures surrounding the balloon 10. For example, the balloon membrane may be formed from substantially inelastic material configured to provide initial expansion and internal pressure and substantially maintain the predetermined expanded shape with minimal additional expansion, e.g., until a rupture or failure pressure is attained, which in one example may be between about five and twenty atmospheres (5-25 atm).

[0075] Thus, when the balloon 10 is expanded, the balloon membrane may generate substantially equal forces in all parts of the balloon 10. For example, as represented in FIG. 1, when the balloon 10 is inflated, e.g., via inflation media (such as an inflation gas or fluid such as saline), the fluid contained within the interior of the balloon 10 may exert a pressure 24 against the walls of the balloon membrane. The resultant force 26 exerted by the fluidpressure 24 upon the proximal section 14 of the balloon 10 may be seen projecting at an angle relative to the longitudinal axis of the catheter 12. A similar resultant force 28 exerted by the fluid pressure 24 upon the distal section 16 of the balloon 10 may also be seen projecting at an angle relative to the longitudinal axis of the catheter 12.

[0076] Each of the resultant forces 26, 28 includes a longitudinally-directed component of force 30, 32, respectively, which are oppositely directed relative to one another. Furthermore, in the absence of any longitudinally-directed tension, a circumferentially-directed tensile force 44 in the wall of the central section 18 generates a radially-directed force 46 to balance the outward force exerted by pressure 42.

[0077] Turning to FIG. 2, an example of a device 8 is shown including an angioplasty catheter 12 carrying a balloon 10 with a supporting structure 50, e.g., a plurality of wires or other fibers (two fibers 52, 54 shown) braided together, on an exterior of the balloon 10, as described further below. Generally, the catheter 12 includes a proximal end, e.g., including a handle or hub (not shown), a distal end 12b sized and / or shaped for introduction into a patient’s body, and one or more lumens 12c extending therebetween, thereby generally defining a longitudinal axis 12d. For example, an inflation lumen 12c may be provided that communicates between a source of inflation media, e.g., a syringe (filled with inflation gas or fluid, such as saline) coupled to a handle or hub on the proximal end (not shown) and an interior of the balloon 10. Optionally, one or more additional lumens may be provided, e.g., a guidewire or instrument lumen extending between a port on the proximal end and an outlet in the distal end (not shown).

[0078] As shown in FIG. 2, the device 8 includes a supporting structure 50 extending over the balloon 10 and attached to opposite ends of the balloon 10, which may be otherwise similar to the balloon 10 shown in FIG. 1 and described elsewhere herein. The fibers 52, 54 of the supporting structure 50 may be wrapped helically around the balloon 10, e.g., as a braid, wrap, mesh, and the like, which may be carried by the balloon 10, e.g., substantially permanently attached to the balloon 10 and / or catheter 12 at one or more locations. For example, with the balloon 10 folded, rolled, or otherwise directed to the contracted condition, the fibers 52, 54 of the supporting structure 50 may be wrapped around and / or otherwise surround the outer surface of the balloon 10 and coupled to the distal end 12b of the catheter 12 and / or to ends of the balloon 10, as described elsewhere herein. Optionally, a preset axial tension may be applied to the fibers 52, 54 when wrapped around and maintained when the ends of fibers 52, 54 are attached relative to the catheter12, e.g., to minimize the low-profile configuration of the supporting structure 50 and / or to constrain the balloon 10 in the contracted condition. This axial tension may be achieved using a tensioning sheath of a predetermined diameter to hold the support braid in position at the optimal tension during the attachment process.

[0079] The supporting structure 50 is illustrated in this variation as two fibers 52, 54, which are positioned offset from one another about the periphery of the balloon 10 and both helically wound around the outer surface of the balloon 10, e.g., in opposite helical directions such that the fibers 52, 54 overlap one another one or more times along the length of the balloon 10. In this example, any torsion induced by the fibers 52, 54 on the balloon 10 may offset one another, thereby providing a net twist on the balloon 10 that is substantially zero. Any number of fibers at various diameters and materials may be used to create the braid support in various patterns of braiding (e.g., over / under, herringbone, etc.,), as described further elsewhere herein.

[0080] The fibers 52, 54 are illustrated as being attached to either the catheter 12 and / or balloon 10 only at proximal and distal attachment locations 56, 58, e.g., attached directly over respective balloon attachment locations 20, 22 while the lengths of the fibers 52, 54 between the attachment locations 56, 58 remain unattached to the balloon 10. For example, opposite ends of the fibers 52, 54 may be attached directly over and to the respective necks or ends 20, 22 of the balloon 10, e.g., by one or more of partially melting the ends of the fibers, welding, bonding with adhesive, and the like.

[0081] Alternatively, separate flux or filler material may be provided that may be used to attached the ends of the fibers 52, 54 to the ends 20, 22 of the balloon 10 and, optionally, to the catheter shaft if the ends 20, 22 of the balloon 10 are not already attached the catheter 12. For example, a section of tubular flux material, e.g., polyamide 12, such as Vestamid Care ML21 and the like (not shown), may be applied or positioned over each of the opposite ends of the fibers 52, 54, and the ends of the 20, 22 of the balloon 10, and heat may be applied to melt the flux material to attach the ends of the fibers 52, 54 to the ends 20, 22 of the balloon 10. Optionally, the heat may be sufficient to also at least partially melt the material of the fibers 52, 54.

[0082] For example, FIG. 9 shows an exemplary cross-section of a balloon neck 20 with the fibers of a braid reinforcement 50 deeply embedded into the material of the balloon, e.g., by externally placing flux material over the ends of the braid or partially melting some of the fibers of the braid, as described further elsewhere herein. Thus, thesupporting structure 50 is disposed external to the balloon membrane and freely movable relative to the balloon outer surface, e.g., along at least the central region 18 and, optionally, along the end sections 14, 16. In addition or alternatively, the ends of the fibers 52, 54 may be attached to the catheter distal end 12b over the attachment locations 20, 22 of the balloon membrane by one or more of wrapping ends of the fibers 52, 54 around the catheter 12, securing the ends to a collar on the catheter 12 (not shown), bonding with adhesive, fusing, heat welding or sonic welding the ends to the catheter 12 and / or to the ends of the balloon membrane, and the like. In one example, the fibers 52, 54 may be formed from thermoplastic material capable of molding and / or fusion, e.g., such that ends of the fibers 52, 54 may be fused together to form a discrete collar at each end of the balloon membrane, e.g., to prevent fraying and / or facilitate attachment to the ends of the balloon 10. The supporting structure 50 may be applied to any number of different length catheters and various balloon structures in addition to those described herein.

[0083] The mechanical properties of a balloon 10 supported by a braid of fibers 52, 54 may depend on the ratio between the diameter of the maximally-expanded braid and the diameter of the maximally-expanded balloon. For example, if the diameter of the maximally-expanded braid (i.e., the maximum diameter to which the braid of fibers 52, 54 can be expanded on the catheter 12 independently of the balloon 10) is less than about one hundred thirty percent (130%) of the diameter of the maximally-expanded balloon 10, the braid may restrict balloon expansion, especially in the central region between the balloon ends. This ratio may result in the balloon assuming a dog-bone shape (i.e., larger towards the ends than the central region) on maximum expansion, with the most restricted central portion never achieving its full unrestricted diameter. If the diameter of the maximally- expanded braid is more than about one hundred fifty percent (150%) of the diameter of the maximally-expanded balloon, the balloon may not form a smooth arc of substantially uniform curvature (especially at high degrees of bending). Instead, the balloon may form a series of relatively straight segments connected by acute bends. Therefore, it may be desirable to maintain the ratio of diameters of maximally-expanded braid to balloon between about one hundred twenty and one hundred sixty percent (120-160%) or between about one hundred thirty and one hundred fifty percent (130-150%).

[0084] Alternatively, while two fibers 52, 54 are illustrated, other variations of the supporting structure 50 may utilize more than two fibers, e.g., one or more sets of fibers wound in opposite directions and configured into a braid, wrap, mesh, and the like, e.g.,between about two and one hundred fibers (2-100), ten and eighty (10-80), twenty and fifty (20-50), e.g., total fibers or in each direction, depending on the application, similar to other examples described elsewhere herein. For example, for smaller balloons, twenty four to forty eight (24-48) fibers may be used, for medium balloons thirty six to seventy two (36- 72) fibers may be used, and for larger balloons, forty eight to ninety six (48-96) fibers may be used. FIG. 8 shows an example of a device 308 that includes a balloon 310 mounted on a catheter 312 with a supporting structure 350 including fibers braided and attached to both ends 320 of the balloon 310 and to the catheter shaft.

[0085] For example, as shown in FIG. 2A, the supporting structure 50a may include fibers 52a, 54a that are braided symmetrically around the exterior of the balloon (not shown) from co-located attachment sites on the proximal and distal ends of the balloon. In the example shown, the fibers 52a, 54a pass in opposite helical directions over and under intersecting fibers, i.e., such that each fiber passes over and then passes under each sequential intersecting fiber that it encounters as it passes from the first end of the braid to the second opposite end. Because the spiral path taken by each fiber of the braid is longer than the direct path taken by both the balloon membrane and the inner catheter, expansion of the balloon may be accompanied by shortening (not the usual lengthening) of the length of the balloon during expansion. Alternatively, as shown in FIG. 2B, each fiber 52b, 54b of the supporting structure 50b may pass over and under every two sequential fibers encountered in a symmetrical pattern.

[0086] In another example, the supporting structure 50b may include fibers that, in at least one direction of the braid, may be provided in sets. For example, as shown in FIG. 2C e.g., pairs of adjacent fibers 52c, 54c are passed over and under intersecting fibers in the same pattern. Thus, each pair of adjacent fibers may pass over and under sequential intersecting pairs of fibers in a symmetrical pattern.

[0087] In yet another example, the supporting structure may include fibers that pass over and / or under multiple intersecting fibers to provide an asymmetrical braid pattern. For example, as shown in FIG. 2D, the supporting structure 50d may include a braid in which fibers 52d passing in a first helical direction pass over two intersecting fibers 54d and the under the next two intersecting fibers, while fibers 54d passing in the second, opposite helical direction may pass over and under alternating intersecting fibers 52d. One particular example of such an asymmetrical braid pattern is a herringbone pattern, e.g., a (1 over 2 under 2) pattern, i.e., where each wire passes over two and then under two intersectingfibers along the length of the braid. Such a pattern may be created using a braiding apparatus including a pair of rotating horn gears that are loaded with fibers and wherein, during operation, the horn gears turn one revolution per pick of the braid. Additional information regarding braid patterns and apparatus and methods for making braided supporting structures may be found at https: / / steegerusa.com / Typical-Braid-Pattems-for- Medi cal -Brai din g / , the entire disclosure of which is expressly incorporated by reference.

[0088] It will be appreciated that many variations of such an asymmetrical pattern may be provided, e.g., in which fibers in one helical direction may pass over (or under) two or more intersecting fibers and then pass under (or over) one or more intersecting fibers uniformly along the length of the balloon, or alternatively, in a nonuniform or other varying manner depending on the desired rigidity characteristics of the resulting balloon catheter.

[0089] Returning to FIG. 2, the catheter 12 itself may generally have a length between the proximal end and the distal end 12b, e.g., ranging between about eighty and one hundred fifty centimeters (80-150 cm) and having an outer diameter between about one and three millimeters (1-3 mm or 3-9Fr). The balloon 10 may have a fusiform shape having an overall length between about ten and one hundred twenty millimeters (10-120 mm) and having an expanded diameter along the central region 18 between two and twelve millimeters (2-12 mm). The ends of the balloon 10 may be attached on the distal end 12b of the catheter 12 adjacent a tapered or other atraumatic distal tip. The balloon 10 generally may be formed from low-compliance thermoplastic material, e.g., mid to high durometer PEB AX, nylon, or PET, and the like.

[0090] Generally, regardless of the number of fibers used or the configuration of the supporting structure 50, the fiber(s) may be formed from substantially inelastic material, i.e., such that each fiber does not substantially stretch or elongate axially, break, or otherwise fail during normal use conditions. For example, the fiber(s) may be formed from a variety of materials, e.g., nylon, Nitinol, Polyethylene naphthalate (PEN), Kevlar Vectraon, Spectra, Dacron, Dyneema, Terlon (PBT), Zylon (PBO), Polyimide (PIM), ultra- high molecular weight polyethylene or polyester, and the like. The fiber(s) may be shaped into substantially round or flat, solid or hollow, ribbons, wires, or other filaments, e.g., by extrusion, weaving or braiding smaller filaments, machining, molding, etching, material deposition, and the like. For example, the fibers may be a diameter or other maximum cross-sectional dimension between about 0.001 and 0.010 inch, e.g., between about 0.002 and 0.003 inch. The resulting fibers may be suitably flexible to be collapsed into a low-profile configuration when the balloon 10 is deflated to its contracted condition, e.g., for stent crimping or loading and / or intravascular delivery. The supporting structure 50 is also suitably flexible to be reconfigured into its deployed configuration when the balloon 10 is inflated to its expanded condition, e.g., for stent deployment or an angioplasty procedure, without substantial plastic or elastic elongation of each fiber along its length.

[0091] In one example, all of the fibers may be formed from polyethylene, e.g., polyethylene naphthalate (“PEN”), which may provide axial strength to the braid. In another example, the fibers include a first set of fibers formed from polyethylene and a second set of fibers formed from polyamide, e.g., Nylon 6, which may provide a source of flux material for the braid. For example, the fibers in the first set may be formed entirely from polyethylene material and the second set may be formed entirely from polyamide. Alternatively, the fibers may include additional materials or may be limited to only one type of material, such as those described elsewhere herein, if desired. For example, coatings or other materials may be added to the fibers that do not substantially change the mechanical properties of the fibers in each set.

[0092] For example, the first set of fibers may be configured to provide the supporting structure with desired tensile strength for the supporting structure, while the second set of fibers may be configured to provide a flux material to facilitate attaching the supporting structure to the balloon. For example, the polyamide fibers may melt at processing temperatures used during assembly of the device, e.g., to fuse the ends of the fibers together and / or to the ends of the balloon, as described elsewhere herein. For example, as shown in FIG. 9, the polyamide fibers may facilitate embedding the ends of the fibers into the balloon neck, thereby securing the fibers without requiring additional materials and / or components.

[0093] In one example, the numbers of fibers in each set may be selected to provide the desired reinforcement and available flux material, e.g., including at least about 50% of the fibers formed from PEN, at least about 60% of the fibers formed from PEN, at least about 70% of the fibers formed from PEN, or at least about 80% of the fibers formed from PEN, with the remaining fibers being formed from polyamide, e.g., Nylon 6. Alternatively, the fibers of the support braid may be 100% from PEN with flux material being added at the attachment sites. The fibers may be distributed substantially uniformly around the circumference of the supporting structure such that the resulting braided mesh may havesubstantially uniform mechanical properties around the circumference and along the length of the mesh.

[0094] Optionally, the fiber(s) of the supporting structure 50 may be porous, e.g., such that one or more compounds may be loaded into the pores of the fiber(s), e.g., one or more therapeutic compounds. Alternatively, the fiber(s) may be coated with such compounds and / or other materials, such as radiopaque or other materials that may facilitate imaging the supporting structure using external imaging when the catheter 12 is introduced into a patient’s body. For example, some of the fibers include iodine, metallic powder, e.g., titanium powder, and the like to increase their radiopacity. Alternatively, some of the fibers may be formed entirely from metal fibers, e.g., gold or platinum, or other materials to increase radiopacity. In addition or alternatively, one or more compounds may be coated, embedded, or otherwise loaded on the outer surface of the balloon 10. When the balloon 10 is directed to the contracted condition, the supporting structure 50 around the balloon 10 may at least partially protect the compounds, e.g., from abrasion, and / or minimize exposure, e.g., until the balloon 10 is inflated and the fibers 52, 54 of the supporting structure 50 separate and expose the outer surface of the balloon 10, whereupon the compounds may be released into the surrounding tissue and / or within the body lumen.

[0095] A supporting structure 50 configured as a mesh of supporting fibers may bend in much the same way as a braided stent, e.g., by reorienting its fibers rather than stretching its fibers. Moreover, the supporting fibers may offer little resistance to bending or curving of the balloon 10 because little energy is needed to reorient such a mesh of fibers. Furthermore, increasing the number of fibers in a supporting structure 50 configured as a braid, wrap, or mesh may reduce or eliminate any bulging by portions of the balloon in the spaces between the fibers, e.g., by reducing the distance between the fibers and / or by further distributing any loads over the fibers, as described elsewhere herein. For example, as shown in FIG. 7, a catheter 112 may be provided that includes a balloon 110 carrying a supporting structure 150 including between about two and two hundred (2-200) fibers 152 wound around the balloon 110 in a helical mesh, e.g., in any of the symmetric or asymmetric patterns described elsewhere herein. The resulting braid may provide geodesic effects that help fix the balloon 110 in a preset or other curved configuration during inflation.

[0096] The braid-covered balloon 110 provides a very stable platform for complex interventions because the balloon may adopt shape of a surrounding lumen into which theballoon is introduced, i.e. providing conformability. In its unexpanded state, the braid- covered balloon 110 may follow the luminal wall from the point of insertion into a target body lumen just like any conventional non-braid covered balloon. However, upon inflation of the braid-covered balloon 110, the braid fibers 154 grip the balloon 110 resulting in the formation of a geodesic pattern of channels on the balloon surface, e.g. as shown in FIG. 7A. This process of imposed patterning of the balloon surface occurs early during the onset of inflation (2-3 ATMs) and is predicated on the environment of the inflated device resulting in conformability to the deployment lumen.

[0097] Once deflated, the balloon 110 may appear to be free from the geodesic effects; however, re-inflation reveals the restoration of the originally imposed geodesic pattern resulting in shape memory for the inflated braid-covered catheter, e.g., similar to the balloon 310 shown in FIG. 8.

[0098] Returning to FIG. 2, additionally, the supporting structure 50 may be attached at its proximal and distal attachment locations 56, 58 such that, when the balloon 10 is inflated, the supporting structure 50 may have a negligible or substantially no effect on the pressure-induced straightening forces exerted on the balloon 10, as described elsewhere herein. In operation, as the balloon 10 is expanded to the expanded condition shown in FIG. 2 and the supporting structure 50 consequently reconfigures itself, the fibers of the supporting structure 50 may impart a tensile force along each of their respective longitudinal axes, as indicated by the tensile reaction forces 60, 64 shown in FIG. 2. The reaction forces 60, 64 may each include in part a respective longitudinally-directed force component, as indicated by longitudinal reaction forces 62, 66. These reaction forces 62, 66 may urge the proximal and distal attachment locations 56, 58 of the supporting structure 50 towards one another, e.g., substantially parallel to the longitudinal axis 12d of the catheter 12, thereby urging the attachment locations 20, 22 of the balloon 10 towards one another as well as compressing axially at least the central region 18 of the catheter 12 (which is designed to shorten reversibly) between the two attachment locations 56, 58.

[0099] Hence, as the balloon 10 expands and is shortened by the supporting structure 50, longitudinally-directed tension 38, 40 in the membrane wall of the balloon 10 may be relieved so that the tension 38, 40 no longer resists the longitudinally-directed component of force 30, 32. Because the expansion of the balloon 10 lengthens the helical path of the fibers of the supporting structure 50, the fibers may tighten and pull or urge the ends of the balloon 10 towards one another. This, in turn, enables the balloon 10 andsupporting structure 50 to retain flexibility in bending or curving, e.g., to conform to the intravascular walls when the balloon 10 is inflated even at relatively high pressures. This is further in comparison to a balloon 10 without such a supporting structure 50 since such a balloon 10 would straighten upon inflation and not be able to bend or curve to the same degree of flexibility.

[0100] In the presence of a supporting structure 50, there is no fixed relationship between the tensile forces in the wall of the balloon 10 along a first direction and tensile forces in the wall along another direction, because the longitudinally directed component of force along the fibers of the supporting structure 50 over the balloon 10 may substitute for or substantially overcome the longitudinal component of tensile force along the balloon wall such that the longitudinal component along the balloon 10 may reduce or fall to zero or close to zero. The longitudinally off-loaded wall thus offers little resistance to bending or curving of the balloon 10.

[0101] In one variation, the catheter 12 may further comprise a “crumple zone” (not shown), e.g., on the distal end 12b between the ends of the balloon 10, which may allow the catheter 12 to reversibly shorten as the balloon 10 shortens. This may result in relatively more longitudinal redundancy, increased differential lengthening between opposite walls, and / or less resistance to bending. These crumple zones may be spring loaded (e.g., via any number of biasing mechanisms such as a slotted Nitinol hypotube, compression spring, and the like, not shown) to facilitate substantially returning to its initial length upon deflation of the balloon 10. Alternatively, the distal end 12b of the catheter 12 may have increased flexibility, e.g., between the attachment locations 20, 22 of the balloon 10, which may allow the distal end 12b to be directed from a generally linear to a helical or other nonlinear shape as the balloon 10 shortens, e.g., similar to the example shown in FIG. 3A and described elsewhere herein.

[0102] Turning to FIGS. 3A and 3B, yet another example of an apparatus 8’ is shown that includes a catheter 12’ including an inflated balloon 10’ thereon having a supporting structure (not shown for clarity) as it is inflated and bent or curved. As shown in FIG. 3 A, when the balloon 10’ expands and becomes shortened due to its supporting structure, the portion 12e’ of the catheter 12’ passing through the balloon interior may become longitudinally compressed and the balloon 10’ itself may form one or more circumferentially oriented folds 60’ along its length. These folds 60’ may allow for differential lengthening between opposing walls of the cylindrical central section 18’ of theballoon 10’ thereby allowing the balloon 10’ to bend or curve, e.g., as shown in FIG. 3B, when such a balloon 10’ would normally be unable to bend due to the rigidity typically imposed when non-compliant balloons are expanded, as described further elsewhere herein. This is illustrated by the respective opposing side walls SI, S2 of the balloon 10’ being substantially equal when the balloon 10’ is inflated and straightened (as shown in FIG. 3 A) but the first side wall length SI becoming lengthened and the opposing second side wall length S2 becoming shortened when the balloon 10 is curved or bent (as shown in FIG. 3B) such that the first side wall length SI forms the outer radius and the second side wall length S2 forms the inner radius of the curved balloon 10,’ i.e., SI » S2. Once the balloon 10’ has been bent or curved, the supporting structure may enable the balloon 10’ to remain in its bent or curved configuration unlike conventional high-pressure balloons.

[0103] As a further illustration of the effect of the supporting structure on an inflated balloon as described herein, FIGS. 4 A and 4B show side views of an exemplary conventional angioplasty balloon 70 having an inflated length LI without any supporting structure integrated with the balloon 70. FIG. 4B illustrates minimal bending or curving of the balloon 70 relative to its straightened configuration when any off-axis force is imparted to the balloon 70, such as when the balloon 70 is inflated within a curved vessel. This is in contrast to a catheter 12 having a supporting structure 50 integrated with a balloon 10, as shown in the side view of FIGS. 5 A and 5B, e.g., which may be similar to the device 8 shown in FIG. 2 or to other examples herein. Although the single fiber 54’ is shown as being helically positioned over the balloon 10, this is intended to be exemplary and any number of additional fibers may be utilized for the supporting structure, as described elsewhere herein.

[0104] When inflated at similar high pressures to the unsupported balloon 70, the balloon 10 having the supporting structure 50 may cause the overall balloon length to shorten slightly during inflation, relieving tension in the balloon 10 and distal end 12b of the catheter 12 within the balloon 10, and providing redundancy that allows differential lengthening between the inner and outer aspects of the balloon 10 when deployed in a curved body lumen. For example, the unsupported balloon shown in FIG. 4A may have a length LI that remains substantially unchanged or somewhat elongates during inflation. In contrast, the balloon 10 with supporting structure 50 may have a deflated length similar to LI, yet, upon inflation, may have a length L2 which is shorter than the initial length LI. Moreover, the resulting balloon 10 of FIGS. 5A and 5B may substantially retain itsflexibility in bending or curving, as shown in the side view of FIG. 5B, unlike the unsupported balloon 70, which resists bending as shown in FIG. 4B.

[0105] Turning to FIG. 6, another example of a balloon device 408 is shown that includes a balloon 410 mounted on a catheter 412, e.g., a single shaft as shown or a pair of concentric shafts (not shown) constructed similar to other devices described elsewhere herein. The device 408 also includes a supporting structure (not shown) attached to ends or neck regions 420, 422 of the balloon 410, generally similar to other devices described elsewhere herein. In addition, the device 408 includes reinforcing cuffs or collars attached over the ends 420, 422 of the balloon 410 (and the ends of the supporting structure, not shown, attached co-locally over the ends 420, 422).

[0106] The cuffs 450 may be attached over the ends 420, 422 directly adjacent the tapered regions of the balloon 410, thereby preventing flaring or other separation of the ends 420, 422 of the balloon 410 from the catheter shaft 412, even when the ballon 410 is inflated to high pressures, e.g., up to twenty five or thirty atmospheres (20-30 atm). The cuffs 450 may be formed from substantially rigid material, e.g., a tubular section of biocompatible material, e.g., stainless steel or other metal, plastic, or composite material. Optionally, the cuffs 450 may be formed from radiopaque material and / or may be coated with radiopaque material to provide markers identifying the ends 420, 422 of the balloon 410, which may facilitate positioning the balloon 410 within a body lumen (not shown) using external imaging, such as fluoroscopy.

[0107] Optionally, the cuffs 450 may include one or more features to enhance attachment to the supporting structure and balloon 410. For example, as shown in FIG. 6, each cuff 450 may include one or more holes 452 (two shown on each cuff 450 as an example) through the wall of the cuff 450, which may receive flux material during assembly of the device 408. In addition or alternatively, the cuffs 450 may include internal ridges, roughened inner surfaces, and the like (not shown) to enhance engagement with the underlying material.

[0108] Turning to FIGS. 10A and 10B, another example of a cuff 450’ is shown that may be attached over each end of a balloon, e.g., instead of the cuffs 450 shown in FIG. 6. As shown, the cuff 450’ includes a tubular section of material, e.g., a stainless steel hypotube including first and second ends 450a’, 450b.’ The cuff 450’ includes a plurality of holes 452’ through the wall of the cuff 450’, e.g., adjacent the second end 450b.’ In the example shown, each hole 452’ includes a circular region 452a’ offset from the end 450b’and a relatively narrow slot 452b’ extending axially from the second end 450b’ to the circular region 452a’, thereby providing a region that may be filled with flux material to enhance attachment of the cuff 450’ to the underlying supporting structure and balloon. As shown, the cuff 450’ includes three holes 452’ spaced apart circumferentially from one another adjacent the second end 450b’, although alternatively, the cuff may include one, three, or more holes, which may have the same size and shape, as shown, or may have different sizes and shapes from one another, if desired.

[0109] Returning to FIG. 6, during manufacturing of the device 408, the balloon 410 and catheter 412 may be manufactured using conventional methods, i.e., with ends 420, 422 of the balloon 410 attached to spaced-apart locations on the catheter 412 (or on concentric shafts, similar to other devices herein), and then the supporting structure and cuffs 450 may be attached co-locally over the ends 420, 422 of the balloon 410. In one exemplary method, the supporting structure may include a plurality of fibers braided in a herringbone pattern, e.g., a 1 over 2 under 2 pattern, thereby providing a braided tubular section sized to slide over the catheter 412 and collapsed balloon 410. The ends of the braided tubular section may be positioned co-locally over the ends 420, 422 of the balloon 410.

[0110] In one example, the fibers are former entirely from PEN or other polyethylene, and the balloon membrane is constructed of Nylon 6, PEBAX, or other material which has a lower Durometer than the fiber material. In this construction, flux or filler material may be positioned around the ends of the braid and the ends 420, 422 of the balloon 410, e.g., a short section of filler material, e.g., formed from polyamide, e.g., Nylon 6, or other material that may be heated to cause the material melt and / or otherwise flow. The cuffs 450 may then be positioned over the flux material, e.g., such that each cuff is located immediately adjacent the tapered region of the balloon 410. For example, as shown in FIGS. 11 A and 1 IB, a proximal cuff 450 is shown positioned over the underlying sleeve of flux material 440, ends of the fibers of the supporting structure 430, and the proximal end 422 of the balloon 410. In this example, the cuff 450 is shorter than the flux material 440 and the length of the fibers and neck 422 of the balloon 410 covered by the flux material 440. Optionally, a section of heat shrink or other material (not shown) may be positioned over the assemblies to retain the components position relative to one another, e.g., to prevent movement during subsequent processing.

[0111] Once the cuffs 450 and other components are properly positioned, the assembly may be heated to melt and / or reflow the flux material, thereby attaching the endsof the fibers of the supporting structure to the underlying ends 420, 422 of the balloon 410. In addition, the flux material may flow into the holes 452 in the cuffs 450 to enhance attachment of the cuffs 450 over the underlying ends. In the alternative shown in FIGS. 10A and 10B, the second ends 450b’ of the cuffs 450’ may be oriented inwardly towards the central region of the balloon 410, e.g., such that the flux material received in the holes 452’ may enhance attachment immediately adjacent the tapered regions of the balloon 410, which may prevent flaring or other separation of the ends of the balloon 410. For example, FIG. 1 IB shows the balloon 410 inflated, thereby expanding the overlying braid of the supporting structure 430, while the cuff 450 prevents the underlying ends from flaring. Thus, only the free, tapered and central regions of the balloon 410 expand during inflation of the balloon 410. If heat shrink is added before heating the assembly, the heat shrink material may be cut or otherwise removed.

[0112] During use, any of the apparatus herein may be used to perform a medical procedure within a patient’s body. For example, with reference to the device 8 shown in FIG. 2, an angioplasty procedure may be performed to dilate or otherwise treat a stenosis or other lesion within a patient’s vasculature. With the balloon 10 in its contracted condition (not shown), the distal end 12b of the catheter 12 may be introduced into the patient’s vasculature from a percutaneous entry site, e.g., in the patient’s femoral, carotid, or other periphery vessel, e.g., in conjunction with a guide catheter, guidewire, and / or other instruments (not shown), similar to conventional interventional procedures. The distal end 12b may be advanced and / or otherwise directed from the proximal end of the catheter 12 to position the balloon 10 across the lesion. The balloon 10 and supporting structure 50 may be sufficiently flexible to allow advancement through tortuous anatomy, e.g., even within a lesion located within a curved or other nonlinear vessel.

[0113] Once positioned within the lesion, the balloon 10 may be inflated to direct the balloon 10 to the expanded condition, thereby causing the supporting structure 50 to reconfigure to its deployed configuration. If the balloon 10 is positioned within a curved vessel or other body lumen, the supporting structure 50 may substantially maintain the balloon 10 in the curved shape corresponding to the body lumen. For example, the supporting structure 50 may cause the balloon 10 to shorten and / or otherwise reconfigure, e.g., generating one or more folds within an inner radius and / or other regions of the balloon 10, thereby providing sufficient flexibility to conform to the curved shape of the lesion despite the non-compliant material of the balloon 10.

[0114] Optionally, before a procedure, the balloon 10 may be prepared to cause the balloon 10 to exhibit “shape-memory,” e.g., biasing the balloon 10 to a desired curved or other shape. For example, immediately before the procedure, the balloon 10 may be inflated to a fully expanded (e.g., substantially straight) condition, while bent into a desired curved shape (e.g., a simple curve having a desired radius of curvature or a more complicated shape, if desired), thereby reconfiguring the supporting structure 50 further to maintain the balloon 10 in the curved shape. For example, the fibers 52, 54 may slide along the outer surface of the balloon 10 to accommodate the curved shape and / or one or more folds may be formed in the balloon 10. The balloon 10 may then be deflated back to the contracted condition.

[0115] Having been expanded in a curved shape, the balloon 10 adopt substantially the same shape upon re-inflation, despite interval deflation and reconfiguration (in the deflated state). A new shape (in the inflated state) may be imprinted on the balloon, if desired, e.g., by forcibly bending the inflated balloon, or by bending the uninflated balloon and re-inflating it while maintaining the new shape.

[0116] This feature may be useful when luminal instrumentation must traverse a curved path. For example, it is often difficult to induce sufficient bending in a conventional dilator to allow passage of a sheath around a bend, branch point, or narrowing. Under these circumstances, a fixed bend in the dilator may be moderately helpful if it were not so difficult to introduce through straight segments of the corporeal lumen or straight segments of the sheath. An uninflated shape-memory balloon may be flexible enough for easy insertion into an obstructing lesion, just beyond the tip of the sheath where balloon inflation induces bending. The sheath may then be advanced with, or over, the suitably sized balloon, past the obstructing lesion and into the target lumen.

[0117] One potential advantage of the balloon 10 and supporting structure 50 described herein is that the supporting structure 50 may facilitate substantially uniform expansion of the balloon 10. For example, with the supporting structure 50 carried by the balloon 10, the balloon 10 may expand substantially uniformly throughout its length during inflation, e.g., unlike a typical non-compliant balloon, which tends to expand to full diameter in one or two locations (e.g., at the ends) before propagating down the balloon (e.g., towards the middle of the balloon).

[0118] In addition or alternatively, the fibers 52 of the supporting structure 50 may decouple the unfurling balloon from the inner surface of an artery within which the balloon10 is inflated, or from the inner surface of a stent (not shown) if carried on the balloon 10. In the absence of a stent, this effect may protect the artery from torsion and dissection since the balloon 10 may be free to unfurl within the surrounding fibers 52 of the supporting structure 50. In the presence of a stent, this effect may increase the security of stent attachment, e.g., since the balloon 10 may be free to slide within the supporting structure 50 as it unfurls and expands, thereby minimizing torsional forces on a stent carried around the supporting structure 50. In contrast, a conventional angioplasty balloon may not attach itself securely to the stent without limiting the necessary rotation that has to occur for a noncompliant balloon to open. Such a configuration may facilitate delivery of multiple independent stents carried on a single balloon, e.g., as disclosed in application Serial No. 14 / 133,542, filed December 18, 2013, the entire disclosure of which is expressly incorporated by reference herein.

[0119] Another advantage of the devices herein is that the supporting structure may protect a patient if the balloon were to somehow rupture or fail within the patient’s body. In contrast, when conventional non-braid-covered balloons rupture during use, the patient may be subjected to embolic events caused by fragments of balloon material that become detached during the balloon rupture event. With the devices herein, the braided material surrounding the balloon may provide a contiguous safety net for such potential balloon fragments by capturing them within the confines of the braided fibers.

[0120] In an alternative example, optionally, the outer surface of the balloon 10 may be configured to enhance engagement between the supporting structure 50 and the balloon 10 during expansion, e.g., to secure the balloon 10 in a curved shape within a similar shaped lesion. For example, the outer surface of the balloon 10 may include a high friction treatment or coating such that the supporting structure 50 may frictionally engage the balloon 10 during expansion to maintain the curved shape and resist the balloon 10 straightening during expansion, which may otherwise cause undesired stress within the vessel within which the balloon 10 is expanded.

[0121] For example, FIG. 7 shows a catheter 112 including a balloon 110 and supporting structure 150, generally constructed similar to other examples herein. The supporting structure 150 includes a plurality of substantially inelastic fibers 154 woven into a braid. Although the example shown includes only a single fiber 154 wound in each helical direction, a more dense braid or mesh may be provided, if desired, e.g., including between two and one hundred fibers wound in each direction. Inflation of the balloon 110exerts an outward force on the fibers 154 of the supporting structure 150, thereby tensioning the fibers 154 between their attachment points proximal and distal to the balloon 110. Thus tensioned, the fibers 154 of the supporting structure 150 may indent slightly into the outer surface 110a of the balloon 110, e.g., creating a slight quilting of the balloon surface (exaggerated in FIG. 7 for effect).

[0122] Optionally, the outer surface 110a of the balloon 110 may include a high friction coating, texture, or other features to increase engagement between the fibers 154 and the balloon 110. The resultant friction between the fibers 154 and the balloon 150 may substantially fix both of them in position when the balloon 110 is inflated, e.g. within a curved or otherwise shape lumen, which may resist bending or subsequent straightening of the balloon 110 and the distal end 112b of the catheter 112 within balloon 110. Optionally, the distal end 112b of the catheter 112 may be constructed to accommodate the curved shape while ensuring that a working lumen 112c through the catheter 112 remains open, e.g., to accommodate one or more instruments therethrough. With the frictional engagement between the fibers 154 and the balloon 110, the distal end 112b of the catheter 112 may transition from flexible to inflexible, which may be useful in an interventional procedure that requires an abrupt change in direction from the site of access to the site of intervention.

[0123] Optionally, the device 8 (or any of the other devices herein) may include one or more markers, e.g., formed from radiopaque, echogenic, or other materials (not shown), that may be provided at desired locations on the distal end 12b, balloon 10, and / or fibers 52, 54 to facilitate identifying the location and / or orientation of the balloon 10 using external imaging, e.g., fluoroscopy, ultrasound, and the like.

[0124] In another option, a stent or other prosthesis (not shown) may be carried on any of the catheters herein, e.g., on the catheter 12 of FIG. 2 over the balloon 10, and the prosthesis may be expanded and / or otherwise deployed within the lesion when the balloon 10 is expanded.

[0125] Optionally, the balloon 10 (of any of the examples herein) may be deflated and inflated one or more times, e.g., within the lesion and / or after positioning to one or more other locations within the patient’s vasculature. Once the procedure is completed, the balloon 10 may be deflated to the contracted condition, thereby reconfiguring the supporting structure 50 to the low-profile configuration, and the catheter 12 may be removed from the patient’s body.

[0126] Returning to FIGS. 2A-2D, examples of asymmetrical braid patterns are now described, which may enhance flexibility of balloon catheters, e.g., during delivery and / or positioning, yet may provide one or more advantages over conventional braids. For example, the asymmetrical braid patterns may provide:

[0127] 1) increased pressure-induced herniation of the balloon membrane outward into the spaces between adjacent braid fibers;

[0128] 2) increased pressure-induced re-orientation of braid fibers to match the patterns imposed by surrounding target vessel geometry;

[0129] 3) braid patterns (for example: 1 over 2 under 2: fully load: Herringbone) designed to minimize bulk, while maximizing braid stability, opening slots in the fiber pattern, increasing the functional thickness and shape retaining the shape-retaining properties of the balloon wall itself; and / or

[0130] 4) desired polymer selection, dictated by the above considerations.

[0131] In one example, although both the balloon and braid fibers may be formed from inelastic materials, the inelasticity and / or hardness of the fibers of the braid may be greater than that of the balloon material. In one particular example, the fibers of the braid may be constructed of PEN and the balloon membrane constructed of Nylon 6, PEBAX, or other material which has a lower Durometer than the fiber material. Consequently, during expansion of the balloon, even while the balloon pressure is still low, shallow geodesic furrows may begin to divide the surface of the balloon membrane into a quilt of tiny diamond or otherwise-shaped segments that together determine the shape of the balloon and the influence of target artery irregularities and bends.

[0132] With a herringbone or other asymmetrical braid configuration (e.g., where at least some of the fibers pass over and / or under two sequential intersecting fibers), the expanded braid may have a radial thickness (the distance from an innermost location of the supporting structure to an outermost location of the supporting structure), which may be greater than twice the diameter or other cross-section of the individual fibers of the braid. For example, in a compressed or delivery configuration, the supporting structure may have radial thickness that is twice the diameter of the individual fibers of the braid, i.e., at the intersecting locations where individual fibers pass over / under one another. Once the balloon is inflated, the fibers may be compressed together such that the radial thickness increases, which may enhance engagement with the underlying balloon and / or otherwise preventing straightening of the balloon.

[0133] During one method of deployment, the balloon may be inflated to an initial pressure, e.g., between about two and four atmospheres or to about four atmospheres, to engage the fibers with the balloon membrane, and the partially deflated, e.g., down to about two atmospheres or less. When the balloon is subsequently inflated, e.g., to pressures as high as about twenty five to thirty atmospheres, the balloon may retain a memory of the shape imposed upon it during the initial inflation. Consequently, the shape memory of the balloon may prevent the balloon from straightening or otherwise changing shape that may otherwise risk damaging the surrounding anatomy, e.g., when the balloon is deployed within complex tortuous anatomy. For example, this method of deployment may allow the balloon to be expanded within dramatically curved, e.g., multi-planar, shapes, such as that shown in FIG. 8 and / or into the shapes of tortuous vessels.

[0134] The applications of the devices and methods discussed above are not limited to angioplasty balloons but may include any number of other inflatable balloon applications. Modification of the above-described assemblies and methods for carrying out the invention, combinations between different variations as practicable, and variations of aspects of the invention that are obvious to those of skill in the art are intended to be within the scope of the claims.

Claims

I claim:

1. A device for performing procedure within a patient’s body, comprising: a tubular member comprising a proximal end, a distal end sized for introduction into a patient’s body, and a longitudinal axis extending therebetween; a non-compliant balloon carried on the distal end comprising a central region and end regions transitioning from the central region to attachment locations on the distal end, the balloon expandable from a contracted condition to an expanded condition; and a supporting structure comprising a plurality of substantially inelastic fibers formed as a braid extending helically around an outer surface of the balloon and comprising opposite ends fixedly attached over the respective attachment locations such that intermediate regions the fibers are movable relative to the central region of the balloon; wherein the fibers are braided in an asymmetrical pattern.

2. The device of claim 1, wherein a first set of fibers of the braid extend in a first helical direction and a second set of fibers of the braid extend in a second helical direction such that the first and second sets of fibers intersect one another as they extend between the opposite ends.

3. The device of claim 2, wherein the fibers of the first set pass over two sequential intersecting fibers of the second set and then pass under two sequential intersecting fibers of the second set at least partially between the opposite ends.

4. The device of claim 3, wherein the fibers of the second set pass sequentially over and under single fibers of the first set at least partially between the opposite ends.

5. The device of claim 3, wherein the fibers of the first set are provided in pairs adjacent one another that pass over and under the same intersecting fibers together.

6. The device of claim 1, wherein the fibers are braided in a herringbone pattern.

7. The device of claim 6, wherein the fibers are braided in a 1 over 2 under 2 pattem.

8. The device of any one of claims 1-7, wherein the fibers are formed from a material having a higher durometer than material of the balloon such that the fibers create furrows to divide the surface of the balloon membrane into a quilt of tiny diamond or otherwise-shaped segments as the balloon is inflated.

9. The device of claim 8, wherein the fibers comprise PEN and the balloon material comprises one of Nylon 6 and PEBAX.

10. The device of any one of claims 1-7, further comprising a collar securing the fibers at the opposite ends to the balloon.

11. The device of claim 10, wherein each collar comprises one or more recesses therein for receiving material of the fibers when attached to the opposite ends of the balloon.

12. The device of claim 11, further comprising flux material melted over the opposite ends of the balloon, the flux material flowed into the one or more recesses of each collar.

13. The device of claim 11, wherein the one or more recesses comprise a hole adjacent a first end of each collar and a relatively narrow slot extending between the first end and the hole, the hole and slot receiving the flux material to enhance attachment to the underlying material.

14. The device of claim 13, wherein the first end of each collar is oriented closer to a central region of the balloon than a second, opposite end of each collar.

15. The device of claim 13, wherein the one or more recesses comprise a plurality of holes adjacent a first end of each collar, the holes spaced apart circumferentially from one another.

16. A device for performing procedure within a patient’s body, comprising:a tubular member comprising a proximal end, a distal end sized for introduction into a patient’s body, and a longitudinal axis extending therebetween; a non-compliant balloon carried on the distal end comprising a central region and end regions transitioning from the central region to attachment locations on the distal end, the balloon expandable from a contracted condition to an expanded condition; and a supporting structure comprising a plurality of substantially inelastic fibers formed as a braid extending helically around an outer surface of the balloon and comprising opposite ends fixedly attached over the respective attachment locations such that intermediate regions the fibers are movable relative to the central region of the balloon; wherein the fibers are braided in a 1 over 2 under 2 herringbone pattern.

17. The device of claim 16, wherein the fibers are formed from a material having a higher durometer than material of the balloon such that the fibers create furrows to divide the surface of the balloon membrane into a quilt of tiny diamond or otherwise-shaped segments as the balloon is inflated.

18. The device of claim 17, wherein the fibers comprise PEN and the balloon material comprises one of Nylon 6 and PEBAX.

19. The device of any one of claims 16-18, further comprising a collar securing the fibers at the opposite ends to the balloon.

20. The device of claim 19, wherein each collar comprises one or more recesses therein for receiving material of the fibers when attached to the opposite ends of the balloon.

21. The device of claim 20, further comprising flux material melted over the opposite ends of the balloon, the flux material flowed into the one or more recesses of each collar.

22. The device of claim 19, wherein the one or more recesses comprise a hole adjacent a first end of each collar and a relatively narrow slot extending between the firstend and the hole, the hole and slot receiving the flux material to enhance attachment to the underlying material.

23. The device of claim 22, wherein the first end of each collar is oriented closer to a central region of the balloon than a second, opposite end of each collar.

24. The device of claim 22, wherein the one or more recesses comprise a plurality of holes adjacent a first end of each collar, the holes spaced apart circumferentially from one another.

25. The device of claim 19, wherein each collar is formed from stainless steel.

26. A device for performing procedure within a patient’s body, comprising: a tubular member comprising a proximal end, a distal end sized for introduction into a patient’s body, and a longitudinal axis extending therebetween; a non-compliant balloon carried on the distal end comprising a central region and end regions transitioning from the central region to attachment locations on the distal end, the balloon expandable from a contracted condition to an expanded condition; a supporting structure comprising a plurality of substantially inelastic fibers formed as a braid extending helically around an outer surface of the balloon and comprising opposite ends fixedly attached over the respective attachment locations such that intermediate regions the fibers are movable relative to the central region of the balloon; and a collar attached over the opposite ends to prevent the attachment locations of the balloons from flaring or otherwise separating from the tubular member.

27. The device of claim 26, wherein each collar comprises one or more recesses therein for receiving material of the fibers when attached to the opposite ends of the balloon.

28. The device of claim 27, further comprising flux material melted over the opposite ends of the balloon, the flux material flowed into the one or more recesses of each collar.

29. The device of claim 27, wherein the one or more recesses comprise a hole adjacent a first end of each collar and a relatively narrow slot extending between the first end and the hole, the hole and slot receiving the flux material to enhance attachment to the underlying material.

30. The device of claim 29, wherein the first end of each collar is oriented closer to a central region of the balloon than a second, opposite end of each collar.

31. The device of claim 29, wherein the one or more recesses comprise a plurality of holes adjacent a first end of each collar, the holes spaced apart circumferentially from one another.

32. The device of any one of claims 26-31, wherein each collar is formed from stainless steel.

33. The device of any one of claims 26-31, wherein the fibers are braided in a herringbone pattern.

34. The device of claim 33, wherein the fibers are braided in a 1 over 2 under 2 pattern.

35. The device of any one of claims 1-7, 16- 18, and 26-31, wherein the braid has a radial thickness greater than twice a diameter or other cross-section of the individual fibers of the braid when the balloon is inflated.

36. A method for making a balloon catheter, comprising: providing a balloon formed from non-compliant material comprising a central region and end regions attached at spaced-apart locations on a tubular member; providing a tubular braid comprising a plurality of inelastic fibers braided helically between opposite ends of the tubular braid; positioning the tubular braid over the balloon such the opposite ends are positioned over respective end regions of the balloon;positioning flux material over each of the opposite ends of the tubular braid and the end regions; and heating the flux material to melt or flow the flux material to attach the opposite ends of the tubular braid to the respective end regions.

37. The method of claim 36, wherein the fibers are formed from a material having a higher durometer than material of the balloon such that the fibers create furrows to divide the surface of the balloon membrane into a quilt of tiny diamond or otherwise-shaped segments as the balloon is inflated.

38. The method of claim 37, wherein the fibers comprise PEN and the balloon material comprises one of Nylon 6 and PEBAX.

39. The method of any one of claims 36-38, wherein the fibers are formed from polyethylene and the flux material comprises polyamide.

40. The method of claim 39, wherein the flux material comprises a section of tubular material having a melting point lower the fibers of the tubular braid.

41. A method for making a balloon catheter, comprising: providing a balloon formed from non-compliant material comprising a central region and end regions attached at spaced-apart locations on a tubular member; providing a tubular braid comprising a plurality of inelastic fibers braided helically between opposite ends of the tubular braid; positioning the tubular braid over the balloon such the opposite ends are positioned over respective end regions of the balloon; positioning flux material over each of the opposite ends of the tubular braid and the end regions; positioning a collar over the flux material on each of the opposite ends of the tubular braid; and heating the flux material to melt or flow the flux material to attach the opposite ends of the tubular braid to the respective end regions.

42. The method of claim 41, wherein providing a tubular braid comprises braiding the fibers into a tubular mesh before positioning the tubular braid over the balloon.

43. The method of claim 42, wherein the fibers of the tubular mesh are braided in a herringbone pattern.

44. The method of claim 43, wherein the fibers of the tubular mesh are braided in a 1 over 2 under 2 pattern.

45. The method of any one of claims 41-44, wherein each collar comprises one or more recesses therein that receive flux material when the flux material melts or flows.

46. The method of claim 45, wherein the one or more recesses comprise a hole adjacent a first end of each collar and a relatively narrow slot extending between the first end and the hole, the hole and slot receiving the flux material to enhance attachment to the underlying material.

47. The method of claim 46, wherein the first end of each collar is oriented closer to a central region of the balloon than a second, opposite end of each collar.

48. The method of claim 45, wherein the one or more recesses comprise a plurality of holes adjacent a first end of each collar, the holes spaced apart circumferentially from one another.

49. The method of any one of claims 41-44, wherein each collar is formed from stainless steel.

50. The method of any one of claims 41-44, wherein each collar has a shorter axial length than the flux material.

51. The method of any one of claims 41-44, wherein the flux material comprises a section of tubular material having a melting point lower the fibers of the tubular braid.

52. The method of claim 51, wherein the tubular material comprises polyamide12.

53. The method of any one of claims 41-44, wherein the fibers are formed from a material having a higher durometer than material of the balloon such that the fibers create furrows to divide the surface of the balloon membrane into a quilt of tiny diamond or otherwise-shaped segments as the balloon is inflated.

54. The method of claim 53, wherein the fibers comprise PEN and the balloon material comprises one of Nylon 6 and PEBAX.

54. The method of any one of claims 41-44, wherein the fibers are formed from polyethylene and the flux material comprises polyamide.

55. The method of any one of claims 41-44, wherein the fibers are formed entirely from polyethylene naphthalate (“PEN”) and the flux material comprises one of Nylon and polycarbonate.

56. The method of any one of claims 41-44, wherein the tubular member comprises a relatively short segment of a catheter, the method further comprising attaching one or more additional tubular members to the segment.

57. The method of any one of claims 41-44, wherein the tubular member comprises inner and outer shafts, and wherein a first end region of the balloon is attached to a distal end of the outer shaft and a second end region of the balloon is attached to a distal end of the outer shaft extending distally from the distal end of the outer shaft.

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