US20110152912A1 - Catheter Having Internal Mechanisms to Encourage Balloon Re-folding - Google Patents

Abstract

A balloon catheter that comprises an inner shaft, a balloon and a sleeve that defines a lumen. A portion of the inner shaft is positioned within the lumen and the balloon is engaged to the sleeve at least two engagement points.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS
• This application is a continuation of application Ser. No. 11/697,133, filed Apr. 5, 2007.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
• Not Applicable
FIELD OF THE INVENTION
• In some embodiments this invention relates to delivery systems, such as catheter systems of all types, which are utilized in the delivery of such implantable medical devices.
BACKGROUND OF THE INVENTION
• Percutaneous transluminal angioplasty (PTA), including percutaneous transluminal coronary angioplasty (PTCA), is a procedure which is well established for the treatment of blockages, lesions, stenosis, thrombus, etc. present in body lumens, such as the coronary arteries and/or other vessels.
• Percutaneous angioplasty makes use of a dilatation balloon catheter, which is introduced into and advanced through a lumen or body vessel until the distal end thereof is at a desired location in the vasculature. Once in position across an afflicted site, the expandable portion of the catheter, or balloon, is inflated to a predetermined size with a fluid at relatively high pressures. By doing so the vessel is dilated, thereby radially compressing the atherosclerotic plaque of any lesion present against the inside of the artery wall, and/or otherwise treating the afflicted area of the vessel. The balloon is then deflated to a small profile so that the dilatation catheter may be withdrawn from the patient's vasculature and blood flow resumed through the dilated artery.
• In angioplasty procedures of the kind described above, there may be restenosis of the artery, which either necessitates another angioplasty procedure, a surgical by-pass operation, or some method of repairing or strengthening the area. To reduce restenosis and strength the area, a physician can implant an intravascular prosthesis for maintaining vascular patency, such as a stent, inside the artery at the lesion.
• The art referred to and/or described above is not intended to constitute an admission that any patent, publication or other information referred to herein is “prior art” with respect to this invention. In addition, this section should not be construed to mean that a search has been made or that no other pertinent information as defined in 37 C.F.R. §1.56(a) exists.
• All US patents and applications and all other published documents mentioned anywhere in this application are incorporated herein by reference in their entirety.
• Without limiting the scope of the invention a brief summary of some of the claimed embodiments of the invention is set forth below. Additional details of the summarized embodiments of the invention and/or additional embodiments of the invention may be found in the Detailed Description of the Invention below.
• A brief abstract of the technical disclosure in the specification is provided as well only for the purposes of complying with 37 C.F.R. 1.72. The abstract is not intended to be used for interpreting the scope of the claims.
BRIEF SUMMARY OF THE INVENTION
• In order to ensure proper catheter withdrawal following angioplasty and/or the delivery of a medical device, embodiments of the present invention are directed to mechanisms which facilitate balloon rewrap about the catheter shaft during deflation of the balloon.
• Such mechanisms include sleeves, biasing members, skeletons or frameworks, plungers, tethers, and other mechanisms alone or in combination with one another. In some embodiments a mechanism is engaged to the catheter shaft, the balloon and/or one or more regions of both in order to refold the balloon before withdrawal.
• These and other embodiments which characterize the invention are pointed out with particularity in the claims annexed hereto and forming a part hereof. However, for further understanding of the invention, its advantages and objectives obtained by its use, reference can be made to the drawings which form a further part hereof and the accompanying descriptive matter, in which there is illustrated and described an embodiments of the invention.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)
• A detailed description of the invention is hereafter described with specific reference being made to the drawings.
• FIG. 1 is a longitudinal cross-section of a balloon catheter with a sleeve positioned around the inner shaft.
• FIG. 2 is a cross-section of the balloon catheter inFIG. 1 taken at line2-2.
• FIG. 3 is a cross-section of the balloon catheter inFIG. 1 taken at line2-2 where the sleeve is partially inflated.
• FIG. 4 is a cross-section of the balloon catheter inFIG. 1 taken at line2-2 where the sleeve is fully inflated.
• FIG. 5 is a longitudinal cross-section of a balloon catheter with both the biasing members and the balloon in an unexpanded state.
• FIG. 6 is the longitudinal cross-section of the balloon catheter inFIG. 5 with both the biasing members and the balloon in an expanded state.
• FIG. 7 is an end view of the balloon catheter inFIG. 5 taken at line7-7 with a fully inflated balloon.
• FIG. 8 is an end view of the balloon catheter inFIG. 6 taken at line7-7 with the balloon in a partially expanded state.
• FIG. 9 is a longitudinal cross-section of a balloon catheter with both the biasing members and the balloon in an unexpanded state.
• FIG. 10 is a partial longitudinal cross-section of a balloon catheter with a member engaged to the balloon.
• FIG. 11 is a cross-section of the balloon catheter inFIG. 10 taken at line11-11.
• FIG. 12 is a cross-section of the balloon catheter inFIG. 10 taken at line11-11 with the member in a folded configuration.
• FIG. 13 is a longitudinal cross-section of a balloon catheter with two sets of tethers engaged to the cones of the balloon with the balloon in an expanded state.
• FIG. 14 is a cross-section of the balloon catheter inFIG. 13 taken at line14-14.
• FIG. 15 is a longitudinal cross-section of a balloon catheter with two sets of inner skeletons in a folded state.
• FIG. 16 is a longitudinal cross-section of the balloon catheter inFIG. 15 with the two sets of inner skeletons in an expanded state.
• FIG. 17 is a longitudinal cross-section of a portion of a balloon catheter with a second embodiment of the inner skeleton in an unexpanded state.
• FIG. 18 is the longitudinal cross-section ofFIG. 18 with the second embodiment of the inner skeleton in an expanded state.
• FIG. 19 is a partial longitudinal cross-section of a balloon catheter with two rings, with the rings in an expanded state.
• FIG. 20 is a cross-section of the balloon catheter inFIG. 19 taken at line20-20 with the ring in an expanded state.
• FIG. 21 is a cross-section of the balloon catheter inFIG. 19 taken at line20-20 with the ring in a folded state.
DETAILED DESCRIPTION OF THE INVENTION
• While this invention may be embodied in many different forms, there are described in detail herein specific embodiments of the invention. This description is an exemplification of the principles of the invention and is not intended to limit the invention to the particular embodiments illustrated.
• For the purposes of this disclosure, like reference numerals in the figures shall refer to like features unless otherwise indicated.
• At least one embodiment of the invention is directed to aballoon catheter10, such as is shown for example inFIG. 1.FIG. 1 shows a longitudinal cross-section of aballoon catheter10 with asleeve40 engaged to theballoon30. Theballoon catheter10 has anouter shaft20, aninner shaft22, asleeve40 and aballoon30. Theouter shaft20 defines aninflation lumen24. Theballoon30 has aproximal waist34a,proximal cone32a, a middle section, adistal cone32band adistal waist34b. The middle section is between theproximal cone32aand thedistal cone32bof theballoon30. Asleeve40 is positioned about theinner shaft22 between theinner shaft22 and theballoon30.
• FIG. 2 is a cross-section of theballoon catheter30 inFIG. 1 taken at line2-2 showing theballoon30 crimped onto thesleeve40 where thesleeve40 is in an unexpanded state. Note that thesleeve40 is not fixedly engaged to theinner shaft22 but it is fixedly engaged to theballoon30. Thesleeve40 is fixedly engaged to theballoon30 at threeengagement regions52, each of which extends along the longitudinal length of thesleeve40, as illustrated inFIG. 1, thereby forming amulti-lobed balloon30. The number ofengagement regions52 between theballoon30 and thesleeve40 depends upon the size of theballoon30. Thus, it is within the scope of the invention for there to be one, two, three, four, five, six, seven, eight ormore engagement regions52 between theballoon30 and thesleeve40. In at least one embodiment, theengagement regions52 are formed by crimping theballoon30 onto thesleeve40.
• In this embodiment, there are threeengagement regions52 positioned in a symmetrical manner about thesleeve40, thereby giving the balloon30 a propeller like configuration. Theengagement regions52 are symmetrical because the amount of balloon material and therefore the size of the lobes between theengagement regions52 is the same. In at least one embodiment, symmetrically placedengagement regions52 cause the symmetrical re-folding of theballoon30. In at least one embodiment, the symmetrically placedengagement regions52 lower both the withdrawal and re-cross forces. In at least one embodiment, theengagement regions52 are not positioned in a symmetrical manner about thesleeve40.
• In at least one embodiment, theengagement regions52 between theballoon30 and thesleeve40 are formed by the heat bonding of compatible materials. In at least one embodiment, formation of theengagement regions52 between theballoon30 and thesleeve40 is enhanced by a coating of adhesive material. In at least one embodiment, at least a portion of the inner surface of theballoon30 has a layer of adhesive. Examples of adhesives include, but are not necessarily limited to, the use of thermoplastic, water-based, reactive chemistries and solvent based adhesives. In at least one embodiment, at least a portion of thesleeve40 has a layer of either thermoplastic adhesives, thermoplastic pressure sensitive adhesives, water based pressure sensitive adhesives, or thermoset adhesives. In at least one embodiment, thesleeve40 is co-extruded with either thermoplastic adhesives, thermoplastic pressure sensitive adhesives, water based pressure sensitive adhesives, or thermoset adhesives.
• Thermoplastic adhesives may be based on polymers including, but not limited to, polyolefin's, including polyethylene and polypropylene, polyamides, polyurethanes, polyesters, polyacrylates, elastomeric block co-polymers, and any co-polymers axed terpolymers thereof. Ethylene vinyl acetate, ethylene methyl acrylate, ethylene-n-butyl acrylate, and so forth, are commonly employed copolymers of ethylene, and homopolymers of ethylene and propylene are commonly employed in thermoplastic adhesives as well. Another class or ethylene copolymers include those referred to in the art as interpolymers of ethylene having at least one C3 to C2O alphaolefin. Thermoplastic adhesive compositions may suitably also include tackifying resins, plasticizers, oils, waxes, antioxidants, and any combination thereof, as well as other additives known to those of skill in the art.
• Thermoplastic pressure sensitive adhesives commonly incorporate rubbery block copolymers such as the styrenic block copolymers including, but not limited to, styrene-isoprene-styrene (SIS), styrene-butadiene-styrene (SBS), styrene-ethylene/propylene-styrene (SEPS), styrene-ethylene/butylene-styrene (SEBS), styrene-isobutylene-styrene (SIBS), and so forth.
• Water based pressure sensitive adhesives commonly incorporate polyacrylic polymers such as styrene-acrylic copolymer, vinyl-acrylic, vinyl ester/vinyl acetate/acrylic; ethylene vinyl acetates, polyurethanes; polyurethane-acrylic hybrids; polyanudes; styrene-butadiene rubbers; polychloroprenes; crylonitrile-butadiene-styrene; polyisoprenes; polyisobutylene; polyurea; natural latex; polysaccharides; gum resins; polyvinyl alcohols; and combinations thereof.
• Thermoset adhesives which are cured by heat, chemical reaction or and/or irradiation, may also be employed herein. There are a variety of thermoset adhesives including heat curing, moisture curing and UV curing, for example. Many such adhesives also come in one and two-part formulations. Suitable UV curable compounds include those having (meth)acrylate functionality such as epoxy (meth)acrylates, urethane (meth)acrylates, polyester (meth)acrylates, acrylic (meth)acrylates, and so forth. Examples of suitable moisture cures include polyurethanes and polyorganosiloxanes. In addition examples of suitable two-component curing systems may include epoxies, polyurethanes, acrylics, and so forth.
• Thesleeve40 has different expansion states, an unexpanded state, an intermediate expanded state and an expanded state, which are illustrated inFIGS. 2,3, and4 respectively. Thesleeve40 is in an intermediate expanded state when it is in neither an unexpanded state nor an expanded state. The expansion state of thesleeve40 depends upon the inflation of theballoon30 by the inflation media. Thus, when the inflation media is withdrawn from theballoon30, thesleeve40 transitions from an expanded state to an unexpanded state.
• FIG. 5 is a longitudinal cross-section of aballoon catheter10 embodiment with at least one biasingmember42. It is within the scope of the invention for theballoon catheter10 to have one, two, three, four, five, six, seven, eight ormore biasing members42. Theballoon catheter10 has anouter shaft20, aninner shaft22, aband50, three biasingmembers42 and aballoon30. Theouter shaft20 defines aninflation lumen24. Theballoon30 has aproximal waist34a,proximal cone32a, a middle section, adistal cone32band adistal waist34b. The middle section is between theproximal cone32aand thedistal cone32bof theballoon30. Theballoon30 is positioned about the balloon region of theinner shaft22 and has an expanded state, an intermediate expanded state and an unexpanded state. The balloon region of theinner shaft22 extends from the proximal end of theproximal waist34aof theballoon30 to the distal end of thedistal waist34bof theballoon30. InFIG. 5, theballoon30 is in an unexpanded state and the biasingmembers42 are in a first unexpanded state. In this embodiment, when the biasingmembers42 are in the first unexpanded state the biasingmembers42 extend alongside theinner shaft22.
• In this embodiment, aband50 is positioned about the balloon region of theinner shaft22 and engages a portion of the biasingmembers42 to theinner shaft22, thereby holding the biasingmembers42 in position about the circumference of theinner shaft22. In at least one embodiment, theband50 is positioned about the middle of the balloon region of theinner shaft22, as illustrated inFIG. 5. Also, theband50 engages the middle portion of each biasingmembers42 to theinner shaft22. However, theband50 may engage any portion of anindividual biasing member42 so long as at least one end of the biasingmember42 engages at least oneballoon cone32. Note that theband50 can have any longitudinal length and shape so long as it engages the biasing member(s)42 and allows the biasing member(s)42 to engage the cones of theballoon30 as described below. In at least one embodiment, theband50 is a wire.
• In at least one embodiment, the biasingmembers42 each have a first end engaged to theband50. In this embodiment, there are two sets of biasingmembers42, a proximal set engaged to the proximal side/end of theband50 and a distal set engaged to the distal side/end of theband50. The second ends of the proximal set of biasingmembers42 in the expanded state are engaged to theproximal cone32awhile the second ends of the distal set of biasingmembers42 in the expanded state are engaged to thedistal cone32b. Note that the biasingmembers42 can have any shape so long as the biasingmembers42 help with balloon re-wrap as discussed below. Also note that the length of the biasingmembers42 depends upon the length between theproximal cone32aand thedistal cone32b.
• In at least one embodiment, the biasingmembers42 are engaged to theinner shaft22. Thus, in this embodiment there is noband50. In this embodiment, there are two sets of biasingmembers42, a proximal set and a distal set. The first ends of the all the biasingmembers42 are engaged to theinner shaft22. The second ends of the proximal set of biasingmembers42 engage theproximal balloon cone32ain the expanded state and the second ends of the distal set of biasingmembers42 engage thedistal balloon cone32b.
• In this embodiment, there are three biasingmembers42 but it is within the scope of the invention for there to be two, three, four, five, six, seven, eight ormore biasing members42. Examples of materials that can be used to make the biasingmembers42 include, but are not limited to polymers, metals, alloys and any combination thereof. Examples of suitable polymers include, but are not limited to, polyamides, polyethylene (PE), Marlex high density polyethylene, polyether-etherketone (PEEK), polyamide (PI), and polyetherimide (PEI), liquid crystal polymers (LCP), acetal, polyoxymethylene (POM), polybutylene terephthalate (PBT), polyether block ester, polyether block amide (PEBA), fluorinated ethylene propylene (FEP), polypropylene (PP), polyvinylchloride (PVC), polyurethane, polytetrafluoroethylene (PTFE), polyimide, polyamide, polyphenylene sulfide (PPS), polyphenylene oxide (PPO), polysufone, nylon, perfluoro (propyl vinyl ether) (PFA), polyether-ester, polymer/metal composites, etc., or mixtures, blends or combinations thereof. One example of a suitable polyether block ester is available under the trade name ARNITEL, and one suitable example of a polyether block amide (PEBA) is available under the trade name PEBAX®, from ATOMCHEM POLYMERS, Birdsboro, Pa. Examples of suitable metals include, but are not limited to, stainless steel, titanium, tantalum, platinum, tungsten, gold and alloys of any of the above-mentioned metals. Examples of suitable alloys include platinum-iridium alloys, cobalt-chromium alloys including Elgiloy and Phynox, MP35N alloy and nickel-titanium alloys, for example, Nitinol. In at least one embodiment, the biasingmembers42 are made of wire. In at least one embodiment, the biasingmembers42 are made from shape memory material such as superelastic Nitinol or spring steel, or may be made of materials which are plastically deformable.
• InFIG. 5, both theballoon30 and the biasingmembers42 are in an unexpanded state. When theballoon30 is in an expanded state, the biasingmembers42 are also in an expanded state. In at least one embodiment, the temperature of the inflation media used to inflate theballoon30 causes shapemember biasing members42 to be in an expanded state. In the expanded state, the first and second ends of the biasingmembers42 extend away from theinner shaft22 and engage the sides of theballoon30.
• In this embodiment, when the biasingmembers42 are in the expanded state, the first ends of the biasingmembers42 engage theproximal cone32aand the second ends of the biasingmembers42 engage thedistal cone32b. In at least one embodiment, at least one end of the plurality of biasingmembers42 is engaged to theproximal cone32aand at least one end of the plurality of biasingmembers42 is engaged to thedistal cone32b. Thus, some of the first ends of the biasingmembers42 do not engage theproximal cone32aand some of the second ends of the biasingmembers42 do not engage thedistal cone32b.
• Thus, when the biasingmembers42 are in an expanded state, the ends (first and/or second) of the biasingmembers42 come into contact with the interior surface of theballoon30. In at least one embodiment, the inner surface of thecones32 is coated with an adhesive which fixedly engages the ends of the biasingmembers42 to the inner surface of thecones32 when the biasingmembers42 contact the inner surface of thecones32, as illustrated inFIG. 6.FIG. 7 is an end view of theballoon30 inFIG. 6 taken at line7-7 and illustrates the biasingmembers42, in the expanded state, extending away from theinner shaft22
• In at least one embodiment, at least one portion of the inner surface of theballoon30 has a layer of adhesive. Examples of adhesives that may be used are described in greater detail above. In at least one embodiment, the portions of the exterior surface of the biasingmember42 which contact the interior surface of theballoon30 in the expanded state has an adhesive coating so that the biasingmember42 engages the interior surface of theballoon30 in the expanded state.
• InFIG. 8, theballoon30 is in an intermediate expanded state. Note that the biasingmembers42 continue to be in an expanded state. When theballoon30 is in the intermediate expanded state and the biasingmembers42 are in the expanded state, the biasingmembers42 support the areas of theballoon30 to which they are engaged and the other areas of theballoon30 not supported by the biasingmembers42 are drawn towards theinner shaft42. In at least one embodiment, theballoon30 is Y shaped when theballoon30 is in an intermediate expanded state and the biasingmembers42 are in an expanded state.
• FIG. 9 is a longitudinal cross-section of theballoon catheter10, showing theballoon30 in a deflated state and the biasingmembers42 in a second unexpanded state. When theballoon30 is fully deflated, thesprings42 assume a second unexpanded state. In the second unexpanded state the biasingmembers42 lay close to theinner shaft22 but the ends of the biasingmembers42 continue to be engaged to the interior surface of theballoon30. Thus, when the biasingmembers42 go from the expanded state to the second unexpanded state, the biasingmembers42 pull the interior surfaces of theballoon30 to which they are engaged towards theinner shaft22.
• In at least one embodiment, the biasingmembers42 only have one unexpanded state. In this embodiment, the unexpanded state of thesprings42 is illustrated inFIG. 9. Thus, the ends of the biasingmembers42 are engaged to the interior surface of theballoon30 while in an unexpanded state, before theballoon30 is in an expanded state, unlike the embodiment illustrated inFIG. 5 and described above. The inflation/deflation cycle in this embodiment begins with theballoon30 and the biasingmembers42 in an unexpanded state, as illustrated inFIG. 9. Then theballoon30 is inflated so that theballoon30 and biasingmembers42 are in an expanded state, as illustrated inFIG. 6. Next, theballoon30 is in an intermediate inflation state and the biasingmembers42 are in an expanded state, as illustrated in the end view ofFIG. 8. Finally, both theballoon30 and the biasingmembers42 return to the unexpanded state ofFIG. 9.
• FIG. 10 is a partial longitudinal cross-section of aballoon catheter10 embodiment with amember44 engaged to theballoon30 at a plurality ofengagement regions52. Themember44 can have any shape so long as it aids in balloon re-wrap as discussed below. In at least one embodiment, themember44 has a substantially round cross-section. In at least one embodiment, themember44 has a ribbon shape. Theballoon catheter10 has anouter shaft20, aninner shaft22, amember44 and aballoon30. Theouter shaft20 defines aninflation lumen24. Theballoon30 has aproximal waist34a,proximal cone32a, adistal cone32band adistal waist34b. The middle section is between theproximal cone32aand thedistal cone32bof theballoon30. Theballoon30 has an expanded state and an unexpanded state.
• Themember44 has an expanded state and a folded state. In both the expanded state and the folded state, themember44 extends about the circumference of theballoon30 and extends along a portion of the length of theballoon30. In this embodiment, themember44 forms a coil in the expanded state that extends from theproximal cone32ato thedistal cone32bof theballoon30, as illustrated inFIG. 10.
• Themember44 is engaged to theballoon30 at a plurality ofengagement regions52. Anengagement region52 is an area of theballoon catheter10 where themember44 is engaged to theballoon30. In this embodiment, theengagement regions52 form three sets of engagement regions with each set of engagement regions on a longitudinal axis which is parallel to theinner shaft22, as illustrated inFIG. 10.FIG. 11 is a cross-section of theballoon30 inFIG. 10 taken at line11-11.
• In at least one embodiment, themember44 is engaged to theballoon30 at theengagement regions52 by an adhesive. Examples of adhesives that may be used are described in greater detail above. In at least one embodiment, themember44 is engaged to theballoon30 at theengagement regions52 by a curable/thermoset adhesive. In at least one embodiment, thermoplastic pressure sensitive adhesives are used to engage themember44 to theballoon30 at theengagement regions52. In at least one embodiment, themember44 is engaged to theballoon30 at theengagement regions52 by a pressure sensitive adhesive. In at least one embodiment, themember44 has a plurality of regions with a layer of adhesive. In at least one embodiment, at least one portion of the inner surface of theballoon30 has a layer of adhesive.
• In at least one embodiment, themember44 has an exterior surface, positioned next to, and engaged to, the interior surface of theballoon30. Thus, in this embodiment, themember44 has nodiscrete engagement regions52 since the entire length of themember44 is engaged to the interior surface of theballoon30. In one embodiment, the exterior surface of themember44 has an adhesive layer by which themember44 engages the interior surface of theballoon30. In one embodiment, the interior surface of theballoon30 has an adhesive layer which engages the exterior surface of themember44.
• In at least one embodiment, themember44 is made of a shape memory material such as superelastic Nitinol or spring steel, or may be made of materials which are plastically deformable. In this embodiment, themember44 is in the expanded state when theballoon30 is in an expanded state and in the folded state when theballoon30 is in an unexpanded state. In at least one embodiment, the temperature of the inflation media determines whether themember44 is in an expanded state or a folded state. In at least one embodiment, themember44 is in a folded state at body temperature. In this embodiment, inflation media having a temperature less than the body temperature is used to inflate theballoon30 and to cause themember44 made of shape memory material transition from a folded state to an expanded state. InFIGS. 10 and 11 both theballoon30 and themember44 are in expanded states.
• When the cool inflation media is withdrawn/evacuated from theballoon30 themember44 warms up to body temperature which causes themember44 to be in the folded state, as illustrated inFIG. 12. Themember44 pulls theengagement regions52 of theballoon30 inwards towards theinner shaft22 when themember44 goes from an expanded state to a folded state. In at least one embodiment, theballoon30 has a Y shape when themember44 is in a folded state. Theballoon30 can have any shape when themember44 is in the folded state so long as theballoon30 can be rewrapped.
• FIG. 13 is a longitudinal cross-section of aballoon catheter10 embodiment with two sets oftethers46. Thetethers46 can have any shape so long as it aids in balloon re-wrap as discussed below. In at least one embodiment, thetethers46 have a substantially round cross-section. In at least one embodiment, thetethers46 have a ribbon shape. Theballoon catheter10 has anouter shaft20, aninner shaft22, aplunger54 with a proximal set oftethers46aand a distal set oftethers46band aballoon30. Theplunger54 can have any shape so long as it can move proximally and distally along theinner shaft22 and aid balloon re-wrap, as discussed below. Theouter shaft20 defines aninflation lumen24. Theballoon30 has aproximal waist34a,proximal cone32a, adistal cone32band adistal waist34b. The middle section is between theproximal cone32aand thedistal cone32bof theballoon30.
• In this embodiment, both the first and second sets oftethers46a,bcomprise threetethers46. It is within the scope of the invention for a set oftethers46 to have one, two, three, four, five, six, seven, eight ormore tethers46. Eachtether46 has a first end engaged to theplunger54. The second ends of the proximal set oftethers46aare engaged to the inside surface of theproximal balloon cone32aatengagement regions52aand the second ends of the distal set oftethers46bare engaged to the inside surface of thedistal balloon cone32batengagement regions52b. Anengagement region52 is an area where a tether engages theballoon30. In at least one embodiment, the second end region of thetether46 is engaged to theballoon30. The second end region includes the second end as well as a portion of thetether46 before the second end.FIG. 14 is an end view of the balloon catheter inFIG. 13 taken at line14-14 and shows theengagement regions52 where thetethers46 and theballoon cone32 are engaged to one another.
• Examples of adhesives that can be used to engage thetethers46 to theballoon30 are described in greater detail above. In at least one embodiment, thetethers46 are engaged to theballoon30 by a pressure sensitive adhesive. In at least one embodiment, thermoplastic pressure sensitive adhesives are used to engage thetethers46 to theballoon30. In at least one embodiment, thetethers46 are engaged to theballoon30 by a curable/thermoset adhesive. In at least one embodiment, theballoon catheter10 has one set oftethers46 engaged to theproximal balloon cone32a. In at least one embodiment, theballoon catheter10 has one set oftethers46 engaged to thedistal balloon cone32b.
• InFIG. 14, theplunger54 is positioned about theinner shaft22 but not engaged to theinner shaft22 so that theplunger54 can move both proximally and distally along theinner shaft22. In at least one embodiment, application of a vacuum, such as occurs during deflation, causes theplunger54 to slide in a proximal direction, thereby pulling thetethers46 in a proximal direction. The movement of theplunger54 in the proximal direction necessarily pulls thetethers46 in the proximal direction and causes the second ends of thetethers46 to move closer to theinner shaft22. Since the second ends of thetethers46 are engaged to the interior surface of theballoon30 atengagement regions52, as the second ends of thetethers46 move closer to theinner shaft22, theengagement regions52 move closer to theinner shaft22. This movement of theballoon30 towards theinner shaft22 causes theballoon30 to collapse and helps with refolding theballoon30.
• Materials that can be used to make thetethers46 include, but are not limited to polymers, mylar fibers or nylon fiber/thread. In at least one embodiment, thetethers46 are made of wire. In at least one embodiment, thetethers46 are made of a polymer. Examples of suitable polymers include, but are not limited to, polyamides, polyethylene (PE), Marlex high density polyethylene, polyether-etherketone (PEEK), polyamide (PI), and polyetherimide (PEI), liquid crystal polymers (LCP), acetal, polyoxymethylene (POM), polybutylene terephthalate (PBT), polyether block ester, polyether block amide (PEBA), fluorinated ethylene propylene (FEP), polypropylene (PP), polyvinylchloride (PVC), polyurethane, polytetrafluoroethylene (PTFE), polyimide, polyamide, polyphenylene sulfide (PPS), polyphenylene oxide (PPO), polysufone, nylon, perfluoro (propyl vinyl ether) (PFA), polyether-ester, polymer/metal composites, etc., or mixtures, blends or combinations thereof. One example of a suitable polyether block ester is available under the trade name ARNITEL, and one suitable example of a polyether block amide (PEBA) is available under the trade name PEBAX®, from ATOMCHEM POLYMERS, Birdsboro, Pa. In at least one embodiment, the second end of thetethers46 are made of a different material than the rest of thetether46.
• Materials that can be used to make theplunger54 include, but are not limited to, polymers, metals, and alloys. Examples of suitable polymers include, but are not limited to, polyamides, polyethylene (PE), Marlex high density polyethylene, polyether-etherketone (PEEK), polyamide (PI), and polyetherimide (PEI), liquid crystal polymers (LCP), acetal, polyoxymethylene (POM), polybutylene terephthalate (PBT), polyether block ester, polyether block amide (PEBA), fluorinated ethylene propylene (FEP), polypropylene (PP), polyvinylchloride (PVC), polyurethane, polytetrafluoroethylene (PTFE), polyimide, polyamide, polyphenylene sulfide (PPS), polyphenylene oxide (PPO), polysufone, nylon, perfluoro (propyl vinyl ether) (PFA), polyether-ester, polymer/metal composites, etc., or mixtures, blends or combinations thereof. One example of a suitable polyether block ester is available under the trade name ARNITEL, and one suitable example of a polyether block amide (PEBA) is available under the trade name PEBAX®, from ATOMCHEM POLYMERS, Birdsboro, Pa. Examples of suitable metals include, but are not limited to, stainless steel, titanium, tantalum, platinum, tungsten, gold and alloys of any of the above-mentioned metals. Examples of suitable alloys include platinum-iridium alloys, cobalt-chromium alloys including Elgiloy and Phynox, MP35N alloy and nickel-titanium alloys, for example, Nitinol.
• In at least one embodiment, the interior surface of theplunger54 has a lubricant. Suitable lubricants include, but are not limited to, fluoropolymer, a silicone coating such as MICROGLIDE™, or HYDROCOAT™ silicones, polyvinyl pyrrolidone, PPO (polypropylene oxide), Teflon® available from DuPont De Nemours, Wilmington, Del. U.S., hydrophobic materials such as silicone lubricant dispersion PN4097, available from Applied Silicone Corp., Ventura, Calif. U.S., or a hydrophilic materials such as hydrogel available from Hydromer, Branchburg, N.J. U.S., hydrophilic polyacrylamide, or lubricious coatings such as those available from Hydro-Silk of Merritt Island, Fla., under the trade name TUA Systems. Additionally, BioSlide™ coating produced by SciMed made be used as well. BioSlide™ is a hydrophilic, lubricious coating comprising polyethylene oxide and neopentyl glycol diacrylate polymerized in a solution of water and isopropyl alcohol in the presence of a photoinitiator such as azobisisobutronitrile. Other hydrogels such as PEG (polyethylene glycol), PEO/PPO/PEO-polyethylene oxide/polypropylene oxide/polyethylene oxide triblock polymer manufactured by BASF or PPO/PEO/PPO may also be used.
• FIG. 15 is a longitudinal cross-section of aballoon catheter10 embodiment with twoinner balloon skeletons56 positioned about theinner shaft22, between the inner shaft and theballoon30. Theballoon catheter10 has anouter shaft20, aninner shaft22, a proximalinner balloon skeleton56a, a distalinner balloon skeleton56band aballoon30. Theouter shaft20 defines aninflation lumen24. Theballoon30 has aproximal waist34a,proximal cone32a, a middle section, adistal cone32band adistal waist34b. The middle section is between theproximal cone32aand thedistal cone32bof theballoon30. Theballoon30 is positioned about the balloon region of theinner shaft22 and has an expanded state and an unexpanded state. The balloon region of theinner shaft22 extends from the proximal end of theproximal waist34aof theballoon30 to the distal end of thedistal waist34bof theballoon30.
• Thebody57 of eachskeleton56 is engaged to the balloon region of theinner shaft22 and eachskeleton56 comprises at least oneprong58. Thebody57 functions to hold theprongs58 at a specific location on the balloon region of theinner shaft22. Thus, thebody57 can have any shape and width. In this embodiment, thebody57 of theskeleton56 is a circumferential rectangular band. In at least one embodiment, thebody57 of theskeleton56 is a non-circumferential band. Thebody57 of theskeleton56 may be made from polymers, metals, alloys and any combination thereof. Examples of suitable polymers include, but are not limited to, polyamides, polyethylene (PE), Marlex high density polyethylene, polyether-etherketone (PEEK), polyamide (PI), and polyetherimide (PEI), liquid crystal polymers (LCP), acetal, polyoxymethylene (POM), polybutylene terephthalate (PBT), polyether block ester, polyether block amide (PEBA), fluorinated ethylene propylene (FEP), polypropylene (PP), polyvinylchloride (PVC), polyurethane, polytetrafluoroethylene (PTFE), polyimide, polyamide, polyphenylene sulfide (PPS), polyphenylene oxide (PPO), polysufone, nylon, perfluoro (propyl vinyl ether) (PFA), polyether-ester, polymer/metal composites, etc., or mixtures, blends or combinations thereof. One example of a suitable polyether block ester is available under the trade name ARNITEL, and one suitable example of a polyether block amide (PEBA) is available under the trade name PEBAX®, from ATOMCHEM POLYMERS, Birdsboro, Pa. Examples of suitable metals include, but are not limited to, stainless steel, titanium, tantalum, platinum, tungsten, gold and alloys of any of the above-mentioned metals. Examples of suitable alloys include platinum-iridium alloys, cobalt-chromium alloys including Elgiloy and Phynox, MP35N alloy and nickel-titanium alloys, for example, Nitinol.
• Although the embodiment inFIG. 15 has fourprongs58, it is within the scope of the invention for askeleton56 to have one, two, three, four, five, six, seven, eight ormore prongs58. Aprong58, as used in this application, is any member, projection, coil, spine, spike, tine, or other means, manufactured and designed so that the second end or the second end region of theprong58 engages the interior of theballoon30. In this embodiment, eachprong58 has a first end engaged to thebody57 of theskeleton56. Note that theprongs58 can be engaged to thebody57 by any suitable means. In at least one embodiment, the first ends of theprongs58 are engaged to the balloon region of theinner shaft22, therefore theskeleton56 does not have abody57.
• In at least one embodiment, theballoon catheter10 has twoskeletons56 and eachskeleton56 has the same number ofprongs58, as illustrated inFIG. 15. In at least one embodiment, theballoon catheter10 has twoskeletons56 and eachskeleton56 has a different number ofprongs58. In this embodiment, eachskeleton56 has fourprongs58 positioned at equal intervals about the circumference of theinner shaft22. In at least one embodiment, theballoon catheter10 has oneskeleton56. In one embodiment, theskeleton56 is positioned at the proximal end of the balloon region of theinner shaft22. In one embodiment, theskeleton56 is positioned at the distal end of the balloon region of theinner shaft22.
• Eachprong58 has an unexpanded state and an expanded state. InFIG. 15 both theballoon30 and theprongs58 are in an unexpanded state, while inFIG. 16 both theballoon30 and theprongs58 are in an expanded state. When theprongs58 are in an expanded state, at least a portion of the second end or the second end region of eachprong58 is engaged to the inner surface of theballoon30. In at least one embodiment, at least a portion of the second end of eachprong58 is engaged to the inner surface of aballoon cone32. In at least one embodiment, at least a portion of the second end of eachprong58 is engaged to the inner surface of the middle section of theballoon30.
• In at least one embodiment, the second end or the second end region of eachprong58 has an adhesive so that the second end region of theprong58 engages the inner surface of theballoon30. Examples of adhesives that may be used on the second end/second end region of eachprong58 are described in greater detail above. In at least one embodiment, the second end or second end region of theprong58 is engaged to theballoon30 by a pressure sensitive adhesive. In at least one embodiment, thermoplastic pressure sensitive adhesives are used to engage theprongs58 to theballoon30. In at least one embodiment, theprongs58 are engaged to the balloon by a curable/thermoset adhesive.
• Theprongs58 can have any shape so long as at least a portion of the second end region of eachprong58, in the expanded state engages the inner surface of a portion of theballoon30. Theprongs58 inFIGS. 17 and 18 have a second end region, which extends from the bend to the second end of theprong58. Aprong58 with a bend along the length of theprong58 provides a greater surface area with which theprong58 can engage the inner surface of theballoon30 when the eachprong58 is in an expanded state. The angle of the bend in theprong58 is an obtuse angle less than 90 degrees. In at least one embodiment, the angle of the bend in theprong58 matches the angle of thecone32. The length between the second end and the bend in theprong58 can be varied so that the greater the length the greater the engagement area between theprong58 and the inner surface of thecone32. However, the angle of the bend and the length between the second end and the bend will affect how close theprong58 will be to theinner shaft22, as is illustrated inFIG. 17. Due to the bend in theprong58, the second end region of theprong58 angles towards theinner shaft22 when theprong58 is in an unexpanded state.
• Theprongs58 may be made from polymers, metals, alloys and any combination thereof. Examples of suitable polymers include, but are not limited to, polyamides, polyethylene (PE), Marlex high density polyethylene, polyether-etherketone (PEEK), polyamide (PI), and polyetherimide (PEI), liquid crystal polymers (LCP), acetal, polyoxymethylene (POM), polybutylene terephthalate (PBT), polyether block ester, polyether block amide (PEBA), fluorinated ethylene propylene (FEP), polypropylene (PP), polyvinylchloride (PVC), polyurethane, polytetrafluoroethylene (PTFE), polyimide, polyamide, polyphenylene sulfide (PPS), polyphenylene oxide (PPO), polysufone, nylon, perfluoro (propyl vinyl ether) (PFA), polyether-ester, polymer/metal composites, etc., or mixtures, blends or combinations thereof. One example of a suitable polyether block ester is available under the trade name ARNITEL, and one suitable example of a polyether block amide (PEBA) is available under the trade name PEBAX®, from ATOMCHEM POLYMERS, Birdsboro, Pa. Examples of suitable metals include, but are not limited to, stainless steel, titanium, tantalum, platinum, tungsten, gold and alloys of any of the above-mentioned metals. Examples of suitable alloys include platinum-iridium alloys, cobalt-chromium alloys including Elgiloy and Phynox, MP35N alloy and nickel-titanium alloys, for example, Nitinol. In at least one embodiment, theprong58 is made from a different material than thebody57.
• In at least one embodiment, theprong58 embodiments described above are made of shape memory material such as superelastic Nitinol or spring steel, or may be made of materials which are plastically deformable. At body temperature, theprongs58 are in either a first or second unexpanded state while at temperatures below body temperature, theprongs58 are in an expanded state. Therefore, theprongs58 are in a first unexpanded state when theballoon catheter10 is advanced to the desired location within the body. Then, inflation media at a temperature below body temperature is used to inflate theballoon30. The temperature of the inflation media causes theprongs58 to transition from the first unexpanded state to an expanded state where theprongs58 become engaged to the interior surface of theballoon30. When the cool inflation media is withdrawn/evacuated during deflation of theballoon30, theprongs58 warm up to body temperature and transition to a second unexpanded state. When theprongs58 transition to the second unexpanded state, the second ends of theprongs58 pull theballoon30 towards theinner shaft22. Thus, in the first unexpanded state, theprongs58 are not engaged to the interior surface of theballoon30 but in the second unexpanded state, theprongs58 are engaged to the interior surface of theballoon30.
• In at least one embodiment, not shown, eachprong58 is a coil having a second end and has an unexpanded state and an expanded state. The second end of the coil shapedprong58 is engaged to the inner surface of theballoon30 when theprong58 is in both the unexpanded state and the expanded state. Expansion of theballoon30 to the expanded state causes the coil shapedprong58 to assume an expanded state. Because the coil shapedprong58 prefers to be in an unexpanded state, when the pressure against the sides of theballoon30 is reduced sufficiently during deflation, the coil shapedprong58 will transition to an unexpanded state and pull theballoon30 towards theinner shaft22. Note that the force of the coil shapedprong58 in the expanded state must be modulated so that a hole is not formed in the side of theballoon30 due to the downward force/tension of the coil shapedprong58.
• FIG. 19 is a partial longitudinal cross-section of aballoon catheter10 embodiment that has aballoon30 withrings48. Theballoon catheter10 has anouter shaft20, aninner shaft22, a proximalinner balloon skeleton56a, a distalinner balloon skeleton56band aballoon30. Theouter shaft20 defines aninflation lumen24. Theballoon30 has aproximal waist34a,proximal cone32a, a middle section, adistal cone32b, adistal waist34b, aproximal ring48aand adistal ring48b. The middle section is between theproximal cone32aand thedistal cone32bof theballoon30. Note that theproximal ring48ais positioned at the proximal end of the middle section and thedistal ring48bis positioned at the distal end of the middle section. Although theballoon catheter10 inFIG. 19 has tworings48, it is within the scope of the invention for there to be one, two, three, four, five, six, seven, eight or more rings48.
• InFIGS. 19 and 20 therings48 and theballoon30 are in an expanded state. Therings48 can have any longitudinal length and thickness. In at least one embodiment, therings48 each have a longitudinal length ranging from 0.0025 inches or 0.06 mm to 0.197 inches or 5 mm. In at least one embodiment, eachring48 has the same longitudinal length. In at least one embodiment, eachring48 has a different longitudinal length. In at least one embodiment, eachring48 has a thickness ranging from 0.0025 inches or 0.06 mm to 0.0394 inches or 1.0 mmFIG. 20 is a cross-section of theballoon catheter10 inFIG. 19 taken at line20-20. In at least one embodiment, therings48 are engaged to the inner surface of theballoon30. In at least one embodiment, theballoon30 is manufactured so that therings48 form a part of the balloon wall.
• InFIG. 21 thering48 is in a folded state. In at least one embodiment, thering48 has a star or wing shape in the folded state. Thering48 is in the folded state when at body temperature and transitions to the expanded state due to inflation pressure.
• In at least one embodiment, therings48 are manufactured from shape memory material. In this embodiment, therings48 are in a folded state at body temperature and in an expanded state at temperatures below body temperature. Thus, therings48 are in a folded state as theballoon catheter10 is positioned within the body lumen Inflation media at a temperature cooler than body temperature is used to inflate theballoon30. The cool inflation media causes therings48 to transition to an expanded state. Therings48 heat back to body temperature and then transition back to the folded state when the cool inflation media is removed/evacuated from theballoon30. This facilitates the refolding of theballoon30.
• Therings48 may be made from shape memory materials such as superelastic Nitinol or spring steel, or may be made of materials which are plastically deformable. In at least one embodiment, therings48 are manufactured from Niti wire.
• In at least one embodiment, theballoon30 is manufactured from compliant material for example, but not limited to, nylon, and polyamines. In at least one embodiment, theballoon30 is made of semi-compliant material, for example, but not limited to, ethylene-vinyl acetate, polyvinyl chloride (PVC), olefin copolymers or homopolymers, polyethylenes, polyurethanes, crosslinked low density polyethylenes (PETs), highly irradiated linear low density polyethylene (LDPE), acrylonitrile polymers and copolymers, acrylonitrile blends and ionomer resins. In at least one embodiment, theballoon30 is manufactured from non-compliant material, for example, but not limited to, polyethylene terephthalates, polyacrylenesulfide, and copolyesters. Other suitable balloon materials may also be used.
• In some embodiments the delivery system or other portion of the assembly may include one or more areas, bands, coatings, members, etc. that is (are) detectable by imaging modalities such as X-Ray, MRI, ultrasound, etc. In some embodiments at least a portion of the assembly is at least partially radiopaque.
• The above disclosure is intended to be illustrative and not exhaustive. This description will suggest many variations and alternatives to one of ordinary skill in this art. The various elements shown in the individual figures and described above may be combined or modified for combination as desired. All these alternatives and variations are intended to be included within the scope of the claims where the term “comprising” means “including, but not limited to”.
• Further, the particular features presented in the dependent claims can be combined with each other in other manners within the scope of the invention such that the invention should be recognized as also specifically directed to other embodiments having any other possible combination of the features of the dependent claims. For instance, for purposes of claim publication, any dependent claim which follows should be taken as alternatively written in a multiple dependent form from all prior claims which possess all antecedents referenced in such dependent claim if such multiple dependent format is an accepted format within the jurisdiction (e.g. each claim depending directly from claim1 should be alternatively taken as depending from all previous claims). In jurisdictions where multiple dependent claim formats are restricted, the following dependent claims should each be also taken as alternatively written in each singly dependent claim format which creates a dependency from a prior antecedent-possessing claim other than the specific claim listed in such dependent claim below.
• This completes the description of the invention. Those skilled in the art may recognize other equivalents to the specific embodiment described herein which equivalents are intended to be encompassed by the claims attached hereto.

Claims (18)

1. A balloon catheter, the balloon catheter comprising an inner shaft, a balloon and a sleeve, the sleeve positioned between the inner shaft and the balloon, the sleeve defining a lumen, a first portion of the inner shaft positioned within the lumen defined by the sleeve, the balloon engaged to the sleeve at least two engagement regions.

2. The balloon catheter ofclaim 1, wherein the sleeve has an outer surface, the outer surface having a layer, wherein the layer is selected from at least one member of the group consisting of thermoplastic pressure sensitive adhesives, thermoplastic adhesives, thermoplastic pressure sensitive adhesives, water based pressure sensitive adhesives, thermoset adhesives, UV curable adhesive compounds, moisture curable compositions, two-component curing systems and any combination thereof.

3. The balloon catheter ofclaim 1, wherein the balloon has an inner surface, the inner surface of the balloon having a layer, wherein the layer is selected from at least one member of the group consisting of thermoplastic pressure sensitive adhesives, thermoplastic adhesives, thermoplastic pressure sensitive adhesives, water based pressure sensitive adhesives, thermoset adhesives, UV curable adhesive compounds, moisture curable compositions, two-component curing systems and any combination thereof.

4. The balloon catheter ofclaim 1, wherein the at least two engagement regions form at least two lobes, each lobe formed by a length of the balloon, the length of each lobe the same.

5. The balloon catheter ofclaim 1, wherein each of the at least two engagement regions extend along a longitudinal length of the sleeve.

6. The balloon catheter ofclaim 1, wherein the at least two engagement regions are three engagement regions positioned in a symmetrical manner about the sleeve.

7. The balloon catheter ofclaim 6, wherein the three engagement regions give the balloon a propeller like configuration.

8. The balloon catheter ofclaim 6, wherein the symmetrically placed engagement regions cause the symmetrical re-folding of the balloon.

9. The balloon catheter ofclaim 6, wherein the symmetrically placed engagement regions lower withdrawal and re-cross forces.

10. The balloon catheter ofclaim 1, wherein the sleeve is coextruded with either thermoplastic adhesives, thermoplastic pressure sensitive adhesives, water based pressure sensitive adhesives, or thermoset adhesives.

11. The balloon catheter ofclaim 1, wherein the at least two engagement regions are formed by heat bonding the balloon and the sleeve.

12. The balloon catheter ofclaim 1, wherein the at least two engagement regions are formed by crimping the balloon onto the sleeve.

13. The balloon catheter ofclaim 1, further comprising an outer shaft, the outer shaft defining an inflation lumen, the inflation lumen in fluid communication with the balloon, a second portion of the inner shaft being positioned within the lumen defined by the outer shaft, the balloon having a first end region and a second end region, the first end region engaged to the outer shaft and the second end region engaged to the inner shaft.

14. The balloon catheter ofclaim 1, the balloon catheter comprising:

a first state wherein the sleeve has a first diameter, and the balloon has at least two lobes;

a second state wherein the sleeve has a second diameter that is greater than the first diameter and the balloon has at least two lobes; and

a third state wherein the sleeve has a third diameter that is greater than the second diameter and the balloon has a substantially circular cross-sectional configuration and an expanded diameter, the expanded diameter of the balloon being greater than the third diameter of the sleeve.

15. A balloon catheter, the balloon catheter comprising a balloon, an inner shaft, and at least one member, the balloon having an interior surface and defining a lumen, the inner shaft positioned with the lumen of the balloon, the at least one member having a first portion and a second portion, the first portion being engaged to the inner shaft by an engagement member, the at least one member having a first state and a second state, the second portion of at least one member being engaged to the interior surface of the balloon only when the at least one member is in the second state.

16. The balloon catheter ofclaim 15, wherein the at least one member is selected from the group consisting of a biasing member or a prong.

17. A balloon catheter, the balloon catheter comprising a balloon, an inner shaft, and a first member, the balloon having an interior surface and defining a lumen, the inner shaft positioned within the lumen of the balloon, a first portion of the first member being engaged to the interior surface of the balloon at an engagement point, the first member having a first state and a second state, the first portion of the first member having a first position relative to the inner shaft when the first member is in the first state and a second position relative to the inner shaft when the first member is in the second state, the second position being closer to the inner shaft than the first position.

18. The balloon catheter ofclaim 17, wherein the first member is selected from the group consisting of a coil, a tether, or a ring.

Images