Balloon Catheter with Multiple Infusion Lumens and Related Methods

Abstract

The present application discloses a device for performing a medical procedure using a filling fluid, which includes: a fillable balloon having an interior for receiving the filling fluid; a first tube including a first filling lumen having a first outlet for conveying a first flow of the filling fluid to the interior of the balloon; and a second tube at least partially positioned within the balloon, the second tube including a second filling lumen having a second outlet for conveying a second flow of the filling fluid to the balloon, wherein the first tube further includes a guide wire lumen.

Description

[0001] This divisional application is a divisional application of a Chinese patent application with an application number of 201380034960.3 (the international application number of which is PCT / US2013 / 062861), a filing date of October 1, 2013, and an invention title of "Balloon Catheter with Multiple Inflation Lumens and Related Methods". A divisional application with an application title of "Balloon Catheter with Multiple Inflation Lumens and Related Methods" and an application number of 201810666699.3 was filed on June 26, 2018 for this invention patent application.

[0002] This application claims the benefit of U.S. Provisional Patent Applications Ser. Nos. 61 / 708,445 and 61 / 747,452, the disclosures of which are incorporated herein by reference in their entireties. Technical Field

[0003] The present disclosure generally relates to devices for performing medical procedures such as angioplasty and balloon-expandable stent / graft delivery. More particularly, the present disclosure relates to balloon catheters and related methods having improved inflation characteristics for optimal stent deployment. Background Art

[0004] Balloon catheters have been designed for use in a variety of medical procedures, including angioplasty and balloon-expandable stent / graft (implant) delivery. Typically, a guide wire introduced percutaneously into a patient's vascular system is advanced through manipulation to a stenotic site. The dilation balloon on the catheter is advanced over the guide wire until the balloon is positioned within the stenosis (which makes it desirable to provide a balloon with a particularly low profile but with sufficient strength to be pushed through the vascular system). Upon inflation, the balloon compresses the stenosis by dilating the blood vessel to re-establish a more adequate blood flow path through the stenosis. To facilitate a uniform compressive pressure distribution along the length of the stenotic lesion, it is the clinical preference that the dilation balloon be sized and centered relative to the stenosis such that the lesion is fully engaged.

[0005] Balloon dilation catheters have also been used in balloon-expandable implant delivery, where the implant is disposed around the balloon and inflated in place at the stenosis. The catheter operator endeavors to deploy the implant directly and precisely onto the diseased tissue of the blood vessel so as to avoid migration to either side of the diseased tissue, thereby avoiding or minimizing the chance of leaving some untreated diseased tissue. Precise deployment also desirably avoids adversely affecting healthy tissue.

[0006] Implant misplacement may occur due to the specific inflation kinetics experienced by an inflatable balloon when deploying an implant. Many balloon-expandable implant delivery catheters preferentially inflate the balloon from the proximal end of the balloon (and may suffer from an inability to transmit the inflation fluid from the proximal end to the distal end due to a compressed or undeployed implant placed over the balloon). During inflation, the expanding balloon may form an asymmetric growth or inflation wave, which can be said to drive or manipulate the implant such that it gradually opens from one end to the other along the wavefront of the inflation wave. The wave may sometimes cause the implant to prematurely disengage from the balloon and may also cause the deployed implant to longitudinally displace away from its delivery site, thereby potentially ineffectively treating a lesion within the patient's vasculature. This premature deployment is often described as "watermelon seeding". Positioning accuracy is also important for stents and stent grafts because missing the target can have detrimental consequences.

[0007] Accordingly, there is a need for a balloon catheter that can be inflated in a preferred manner and with better regulation to facilitate the proper delivery of stents, stent grafts, etc., without sacrificing the desired low-profile arrangement. SUMMARY OF THE INVENTION

[0008] An object of the present disclosure is to provide a balloon catheter that can be inflated in a preferred manner to facilitate the proper delivery of stents, stent grafts, etc.

[0009] In one aspect, an apparatus for performing a medical procedure using an inflation fluid includes an inflatable balloon having an interior for receiving the inflation fluid. A first tube includes a first inflation lumen having a first outlet for transmitting a first flow of the inflation fluid to the interior of the balloon. A second tube is at least partially positioned within the balloon and includes a second inflation lumen having a second outlet for transmitting a second flow of the inflation fluid to the balloon.

[0010] In one embodiment, the first tube further includes a guidewire lumen. The first inflation lumen and the guidewire lumen may be coaxial proximal to the balloon. The first outlet of the first inflation lumen may also be located within the proximal cone of the balloon, and the second outlet of the second inflation lumen may be located within the distal cone of the balloon. In this way, preferential inflation can be avoided to avoid the problem of stent "watermelon seeding" caused by non-uniform inflation waves (proximal to distal or vice versa).

[0011] In these and other embodiments, the first tube may extend a first distance into the interior of the balloon and the second tube may extend a second distance into the interior of the balloon. The first and second tubes may have different diameters, may comprise different materials, or may comprise a combination of both. In any case, the balloon may comprise a therapeutic agent, a stent, a stent graft, or any combination thereof.

[0012] The proximal end of the second tube forming the second inflation lumen may be spaced from the first outlet of the first inflation lumen. When a stent or stent graft is disposed on the balloon over the second tube, it provides a conduit for delivering inflation fluid supplied from the first outlet of the first inflation lumen to the proximal portion of the balloon to the distal portion of the balloon associated with the second outlet of the tube such that when the balloon is inflated, the stent or stent graft expands. The second tube may be longer than the stent or stent graft and may have a wall thickness in the range of about 0.0005 inches to about 0.0025 inches.

[0013] The balloon may define a proximal cone, a distal cone, and a cylinder between the proximal and distal cones, and wherein the second tube has a proximal end spaced from the first outlet and the length of the second tube is greater than or equal to the length of the cylinder. The second inflation lumen does not receive inflation fluid from the first outlet of the first inflation lumen. The first tube may also be connected to and support the balloon. The associated first outlet of the first inflation lumen may be located proximal to the balloon.

[0014] Another aspect of the present disclosure relates to an apparatus for performing a medical procedure using an inflation fluid, comprising an inflatable balloon having an interior and at least two inflation tubes, the inflation tubes being at least partially positioned within the interior of the balloon in a side-by-side arrangement for delivering inflation fluid to the interior. The at least two inflation tubes comprise a first inflation tube having a first length and a second inflation tube having a second length different from the first length.

[0015] The apparatus may also comprise a guide wire lumen having an outer surface that supports the two inflation tubes within the interior of the balloon. A stent or stent graft may also be disposed on the balloon. The at least two tubes may have different sizes or comprise different materials. Each of the at least two tubes may comprise a proximal end connected to a separator positioned within an inflation lumen of an axis supporting the balloon. The first tube of the at least two tubes may comprise a distal end positioned within the distal cone of the balloon and the second tube of the at least two tubes comprises a distal end within the proximal cone of the balloon.

[0016] Another aspect of the present disclosure relates to an apparatus for performing a medical procedure using an infusion fluid. The apparatus includes an inflatable balloon having an interior for receiving the infusion fluid and a tube including an infusion lumen having a septum therein. The septum is for dividing a single flow of the infusion fluid into a first infusion lumen having a first outlet for providing a first flow of the infusion fluid to the interior of the balloon and a second infusion lumen having a second outlet for providing a second flow of the infusion fluid to the balloon.

[0017] In one embodiment, a first tube forming the first infusion lumen has the first outlet and extends distally of the balloon to a distal cone of the balloon. The apparatus may further include a second tube forming the second infusion lumen and having the second outlet. The second tube may extend proximally of the balloon to a proximal cone of the balloon.

[0018] Another aspect of the present disclosure relates to a balloon device including a guidewire lumen, a balloon positioned over the guidewire lumen, and an infusion lumen in fluid communication with the balloon. A conduit within the balloon and coaxial with the guidewire lumen has an internal dimension greater than an external dimension of the guidewire lumen. A region between the internal dimension of the conduit and the external dimension of the guidewire lumen defines a flow path for conveying the infusion fluid from a proximal section of the balloon to a distal section of the balloon.

[0019] In one embodiment, the conduit includes a tube having a wall thickness in the range of from about 0.0005 inches to about 0.0025 inches and more particularly about 0.0015 inches. The conduit may float freely over the guidewire lumen or may be fixedly attached to the guidewire lumen. The balloon may define a proximal cone, a distal cone, and a body section between the proximal and distal cones, and wherein the length of the conduit is greater than or equal to the length of the body section. A shaft may be provided for supporting the balloon and includes an infusion lumen having an outlet in communication with the interior of the balloon, and wherein the conduit includes a proximal end spaced from the outlet of the infusion lumen.

[0020] Another aspect of the present disclosure relates to an apparatus for performing a medical procedure using an infusion fluid, the apparatus including a balloon having an interior that can be inflated with an infusion fluid, the balloon having a balloon length. An implant supported by the balloon has an implant length. A tube extends within the interior of the balloon for delivering the infusion fluid into the balloon, the tube having a tube length that is less than the balloon length and greater than the implant length.

[0021] In one embodiment, the balloon includes a proximal cone and a distal cone, and wherein the tube includes a first end within the proximal cone and a second end within the distal cone. The inflation lumen may include an outlet, and the tube includes a proximal end that includes an inlet for receiving inflation fluid from the outlet of the inflation lumen.

[0022] Another aspect of the present disclosure relates to a method of inflating a balloon with inflation fluid. The method includes delivering inflation fluid to the balloon through at least two inflation tubes, the inflation tubes being at least partially positioned inside the balloon in a side-by-side arrangement. The at least two inflation tubes include a first inflation tube having a first length and a second inflation tube having a second length different from the first length. The method may further include delivering a first flow of inflation fluid to the proximal cone of the balloon through the first inflation tube and delivering a second flow of inflation fluid to the distal cone of the balloon through the second inflation tube.

[0023] Yet another aspect of the present disclosure relates to a method of inflating a balloon. The method includes delivering inflation fluid to a septum that divides the flow into first and second portions before entering the interior of the balloon, delivering the first portion of the flow of inflation fluid to the proximal cone of the balloon, and delivering the second portion of the flow of inflation fluid to the distal cone of the balloon. The step of delivering the first portion of the flow may be accomplished using a first tube connected to the septum at the proximal end and terminating in the proximal cone. The step of delivering the second portion of the flow may be accomplished using a second tube connected to the septum at the proximal end and terminating in the distal cone.

[0024] Another aspect of the present disclosure relates to a method of inflating a balloon, which includes providing a balloon device including a balloon positioned over a guidewire lumen, and a conduit coaxial with the guidewire lumen within the balloon, the internal dimension of the conduit being greater than the external dimension of the guidewire lumen, the region between the internal dimension of the conduit and the external dimension of the guidewire lumen defining a fluid flow path from the proximal segment of the balloon to the distal segment of the balloon. The method further includes the step of transmitting fluid through an inflation lumen in fluid communication with the balloon, a portion of the fluid moving through the fluid flow path such that the proximal segment and the distal segment of the balloon are simultaneously inflated.

[0025] Another aspect of the present disclosure relates to an endoluminal prosthesis including a stent structure, the stent structure including a plurality of stent units, the stent units including a series of stent elements repeating in the circumferential direction. The stent elements include a plurality of first, V-shaped stent elements having a first leg portion, a second leg portion, and a peak portion, the V-shaped stent elements having at least four different orientations, and a plurality of second V-shaped stent elements connecting adjacent first V-shaped stent elements such that the second leg portion of each of the first V-shaped stent elements is connected to a second V-shaped element, and the second leg portion of each of the first V-shaped stent elements tapers in width towards the second V-shaped stent element. A plurality of connectors may connect adjacent stent elements.

[0026] In one embodiment, the first leg portion of each of the first V-shaped stent elements is parallel to the longitudinal axis of the prosthesis. The peak portion of the first V-shaped stent element in the first orientation is longitudinally spaced from the peak portion of the first V-shaped stent element in the second orientation, wherein the first orientation and the second orientation are adjacent to each other. The peak portion of each of the four orientations of the first V-shaped stent element may be longitudinally spaced from the peak portion of an adjacent first V-shaped stent element. The distance may range from about 0.005 inches to about 0.035 inches and more particularly be about 0.012 inches. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a partial cross-sectional side view of a balloon catheter according to one aspect of the present disclosure;

[0028] Figure 2 is a partial cross-sectional perspective view of a balloon catheter according to the present disclosure;

[0029] Figure 2a 、 2b and 2c are cross-sectional views taken along Figure 2 lines 2a-2a, 2b-2b, and 2c-2c of;

[0030] Figure 3 is a partial cross-sectional side view of a balloon catheter according to the present disclosure;

[0031] Figure 3 a is a cross-sectional view taken along Figure 3 line 3a-3a of;

[0032] Figure 3 b and 3c are cross-sectional views taken along Figure 3 lines 3b-3b and 3c-3c of, showing one embodiment;

[0033] Figure 3 d and 3e are along Figure 3Cross-sectional views obtained along lines 3d-3d and 3e-3e, showing an embodiment;

[0034] Figure 4 is a partial cross-sectional perspective view of a balloon catheter according to the present disclosure, wherein the balloon is in an inflated state;

[0035] Figure 5 is along Figure 4 Cross-sectional view obtained along line 5-5;

[0036] Figure 6 is a partial cross-sectional perspective view of a balloon catheter according to the present disclosure, wherein the balloon is in a folded state;

[0037] Figure 7 is an enlarged side view of a stent device forming another aspect of the present disclosure;

[0038] Figure 8 is another side view of the stent device; and

[0039] Figure 9 is an enlarged side view of the stent device. Detailed Description

[0040] Unless otherwise stated, the description provided below and with respect to the drawings applies to all embodiments, and features common to each embodiment are similarly shown and numbered.

[0041] Now referring to Figure 1 , a device according to one aspect of the present disclosure includes a catheter 10 having an inflatable balloon 12. The balloon 12 may be mounted adjacent to the distal end of a catheter shaft in the form of a tube 14 and is thus supported thereby (although the balloon 12 may not be directly attached to the tube 14). The proximal end 12a and the distal end 12b of the balloon 12 may be in the form of cones or generally conical segments or "cones" N or "cylinders B" separated by a generally cylindrical body segment. The balloon 12 may include a single or multiple layers of balloon walls forming an interior for receiving a filling fluid.

[0042] The balloon 12 can be made of typical materials, including polymers such as polyethylene terephthalate (PET), polyetherimide (PEI), polyethylene (PE), polytetrafluoroethylene (PTFE), expanded polytetrafluoroethylene (ePTFE), ethylene tetrafluoroethylene copolymer (ETFE), fluorinated ethylene propylene (FEP), polyoxymethylene (POM), polybutylene terephthalate (PBT), block polyether ester, polyurethane, polypropylene (PP), polyvinyl chloride (PVC), polyether ester, polyester, polyamide, elastic polyamide, block polyamide / ester, block polyether amide, silicone, Marlex high density polyethylene, Marlex low density polyethylene, linear low density polyethylene, polyetheretherketone (PEEK), polyimide (PI), polyphenylene sulfide (PPS), polyphenylene ether (PPO), polysulfone, nylon, perfluoro(ethyl vinyl ether) (PFA), other suitable materials, or their mixtures, combinations, copolymers, polymer / metal composites, etc. The wall thickness of the balloon 12 can vary depending on the burst pressure requirements and hoop strength of the balloon material. Fibers, rods or other types of reinforcing structures can also be included along, within or as part of the balloon wall, which can also have radiopaque properties to allow visualization under fluoroscopy.

[0043] The balloon 12 can be non-compliant, having a balloon wall that maintains its size and shape in one or more directions when the balloon is inflated to apply a treatment, which may include drugs or an expandable endoprosthesis (e.g., a stent S, a stent graft or a similar implant device) positioned or deployed by means of the catheter 10. In the case of the stent S, the inflation of the balloon 12 can also cause the inflation of the stent for delivery into an associated blood vessel or other body cavity. The stent S can be constructed at least in part of any of a variety of materials, such as stainless steel, nickel, titanium, nitinol, platinum, gold, chromium, cobalt and any other metals and their combinations or alloys. In some embodiments, the stent can be constructed at least in part of a polymeric material, such as a shape memory polymer. In some embodiments, the balloon 12 or the implant carried by it can include one or more therapeutic and / or lubricious coatings.

[0044] The balloon 12 can also have a constant surface area during and after inflation. The balloon 12 can also have a predetermined length and a predetermined diameter that remain constant during and after inflation. However, depending on the specific use for which it will be used, the balloon 12 can be semi-compliant or compliant.

[0045] The tube 14 serving as the catheter shaft includes a lumen 16 forming a conduit for supplying a filling fluid (e.g., saline with or without contrast agent) from a remote source (e.g., a filling device not shown) to the balloon 12. As Figure 1As shown, the inflation lumen 16 supplies fluid to the balloon 12 via two discrete channels, thereby creating independent fluid flows for inflating different portions of the balloon 12. For example, fluid delivery can occur through a first lumen 16a for delivering a first portion of the flow and a second, discrete lumen 16b for delivering a second portion of the flow.

[0046] Each lumen 16a, 16b can be positioned at a different location relative to the interior of the balloon 12. Specifically, the first lumen 16a can be formed by a first tube 18a having an outlet O1 positioned at the proximal end 12a of the interior I of the balloon, e.g., adjacent the proximal cone N when inflating the balloon. The second lumen 16b can be formed by a second tube 18b including an outlet O2, which can be positioned at the distal end 12b of the balloon 12, adjacent a second, distal cone N. It will be understood that the term "tube" is used herein to denote a discrete structure including an outer wall having an inner surface forming a conduit or lumen with an inlet and an outlet, rather than merely denoting a lumen within a structure.

[0047] One or both of the first and second tubes 18a, 18b can be attached to the tube 14 forming the catheter shaft or can be separated therefrom. The tube 14 can also include a guidewire lumen 22 arranged to allow a guidewire G to pass therethrough (which can be introduced in an "over-the-wire" (OTW) or "rapid exchange" (RX) configuration). In either case, the guidewire lumen 22 extends completely from the proximal end 12a to the tip P adjacent the distal end 12b of the balloon 12. The guidewire lumen 22 can be provided by a smaller diameter tube 14a forming an extension or a portion of the tube 14 extending within the interior I of the balloon, which can extend to the proximal end of the catheter 10 and an interface (not shown).

[0048] In one particular embodiment, as Figure 2 shown, the catheter 10 includes a coaxial arrangement. In such an arrangement, the guidewire lumen 22 is coaxial with at least a portion of the inflation lumen 16 in at least the portion of the tube 14 proximal to the balloon 12 (see Figure 2a ). In this approach, a separator, such as a transverse baffle 24, can be provided adjacent the inlets of the dual inflation lumens 16a, 16b (e.g., proximal to the inlets) and can be associated with the tubes 18a, 18b for conveying the flow of inflation fluid (see Figure 2b ). Thus, the fluid flow reaching the balloon 12 is split and enters the interior I of the balloon as a first flow F1 through one lumen 16a at a first location corresponding to the outlet O1 closer to the proximal end 12a and a second flow F2 through the other lumen 16b at a second location corresponding to the outlet O2 closer to the distal end 12b (and forming a side-by-side arrangement with the portion of the tube 14 forming the guidewire lumen 22).

[0049] It can be appreciated that by selecting the lengths and diameters of the different tubes 18a, 18b, the infusion fluid can thus be supplied to different parts of the balloon 12 in a strategic manner in different flows. This allows for precise control of the relative inflation of the balloon 12, as opposed to arrangements where the fluid can enter the balloon either proximally or distally. Such precise control can help avoid different inflation characteristics that can lead to misplacement or misalignment of the corresponding loads carried thereon, such as stents, stent grafts, or other treatments.

[0050] In one embodiment, as Figure 3 shown, the catheter 10 having a plurality of infusion channels for delivering the flow of infusion fluid to the balloon 12 is a dual-lumen configuration. The catheter 14 thus includes a guidewire lumen 22 (which can extend through the entire balloon 12) and a separate infusion lumen 16. This infusion lumen 16 (which is shown in Figure 3 a as having a long bend or crescent shape in the transverse direction) can also be divided into two or more infusion lumens 16a, 16b. This division can occur at a transition zone T created by a separator, such as a transverse partition 24 within the infusion lumen 16 proximal to the proximal end 12a of the balloon 12. Thus, the flow of the infusion fluid can be divided before entering the interior of the balloon 12.

[0051] Although Figure 3 a single catheter 10 is shown, the arrangement of the dual lumens 16a, 16b can vary in different embodiments, as shown in cross-section. For example, in one embodiment, as Figure 3 shown in b and 3c, two separate tubes 18a, 18b create the dual infusion lumens 16a, 16b and are supported within the balloon 12 along the outer surface of the tube 14a that forms the guidewire lumen 22. In another embodiment, as Figure 3 shown in d and 3e, a first lumen 16a is provided adjacent to the proximal end of the transition zone T (e.g., by simply forming a hole in a structure that serves as the partition 24), and another lumen 16b corresponds to a separate tube 18b that extends into and at least partially through the interior I of the balloon 12. It can be appreciated that the length of the portion of one or more tubes 18a, 18b within the balloon 12 can be less than the length D of the balloon 12 in the longitudinal direction (the balloon length D can be considered herein as the distance between the end of the cone N at the distal end 12b and the end of the cone N at the proximal end 12a).

[0052] It should be appreciated that the ability to provide multiple inflation lumens 16a, 16b of different sizes or lengths including tubes 18a, 18b allows for optimal control of the inflation of the balloon 12. Specifically, the positions of the outlets O1, O2 can be selected to correspond to a desired inflation profile, which in most cases includes using different flows of fluid to inflate the proximal and distal cones N of the balloon 12 at substantially equal rates to ensure proper deployment of an expandable implant, such as a stent or a stent graft (if any), and even treatment, such as the application of a drug. In a dual lumen embodiment, a single inflation lumen 16b can extend to the cone N at the distal end 12b of the balloon 12, while the outlet of the proximal inflation lumen 16a can simply be provided at the transition zone T without extending into the interior of the balloon 12. Thus, a low-profile catheter 10 can be provided. Additionally, the materials of the corresponding tubes 18a, 18b can be selected to provide different characteristics in terms of flexibility and strength.

[0053] The relative diameters of the lumens 16a, 16b can also be selected to control the relative amounts of inflation fluid delivered to different internal portions of the balloon 12. For example, a larger diameter tube 18b can be used to deliver inflation fluid to the distal end 12b, while a smaller diameter tube 18a can be used to deliver inflation fluid to the proximal end 12a, thus explaining the pressure difference due to the additional travel distance. Similarly, changing the length of one or both of the tubes 18a, 18b allows for precise control of the positions of the corresponding outlets O1, O2, which means that the inflation fluid can have a more pronounced effect at the corresponding positions of the balloon 12 when exiting (e.g., within the cones N at the proximal and distal ends 12a, 12b of the balloon 12, thus helping to prevent the undesired state of "watermelon seeding" mentioned in the previous discussion). Due to this multi-stage, enhanced adaptability, an optimal inflation profile can be provided, which can help avoid problems caused by differential inflation, especially when the balloon carries a treatment, such as a stent, a stent graft, a drug, or any combination of the foregoing.

[0054] Although the use of one or two tubes 18a, 18b is shown, more than two tubes can be used while achieving the desired goal of substantially uniform inflation. For example, a third tube can be provided to deliver inflation fluid to the intermediate cylindrical section or cylinder B of the balloon 12. Similarly, pairs of tubes can be provided to deliver inflation fluid to the interior I of the balloon, such as at or near the proximal and distal cones N.

[0055] Figure 4 The catheter 10 is also shown to include an expandable inner prosthesis, such as a stent S or a stent graft having a length E that is less than the length D of the balloon. Figure 5FIG. 0 is a cross-sectional view of a possible construction of display tube 14, the tube including a filling lumen 16, and a guide wire lumen 22 formed by tube 14a that extends completely from proximal end 12a to tip P adjacent distal end 12b of balloon 12. The filling lumen 16 leads to proximal end 12a of balloon 12, which may be connected at proximal end 12a to tube 14 forming the catheter shaft and at distal end 12b to tip P that receives guide wire lumen 22.

[0056] Combined reference Figure 4 and 6 , it can be understood that conduit 30 for conveying a filling fluid (such as a contrast agent) is disposed within balloon 12 above guide wire lumen 22, which is shown partially in phantom. Thus, the filling lumen formed between the inner surface of the tube forming conduit 30 and the tube forming guide wire lumen 22 can be annular. Thus, when a stent or other implant is in a compressed or unexpanded state (S') on folded balloon (12'), fluid can flow from an inlet adjacent proximal end 12a of balloon 12 into conduit 30 and reach an outlet adjacent distal end 12b. Thus, the mounted stent S' remains stationary on balloon 12 during insertion and filling, and a watermelon seeding state can be avoided.

[0057] Conduit 30 can be a thin-walled tube positioned along guide wire lumen 22 and can be positioned over a corresponding portion of tube 14 that forms at least a portion of the guide wire lumen, as shown. In this particular embodiment, conduit 30 and guide wire lumen 22 are coaxial, but it should be appreciated that the conduit can also take the form of an auxiliary tube carried on tube 14 within balloon 12 in a non-coaxial or side-by-side configuration. It can also be appreciated from the illustrated embodiment that conduit 30 is not directly connected to filling lumen 16, which can terminate at the end of tube 14 forming the catheter shaft adjacent proximal end 12a of balloon 12. Conduit 30 can thus include an open end or inlet closer to or at proximal end 12a of balloon 12 and can also include an open end or outlet closer to or at distal end 12b of balloon 12.

[0058] The wall thickness of the thin-walled tube forming conduit 30 is in the range of about 0.0005 inches to about 0.0025 inches in one embodiment and can be about 0.0015 inches. It can be appreciated that positioning the thin-walled tube or conduit over tube 14 including guide wire lumen 22 to which balloon 12 is attached at proximal end 12a and distal end 12b allows simultaneous filling of the distal and proximal balloon cones N and prevents migration of an implant (such as stent S). Conduit 30 can be used on a variety of existing catheter assemblies to provide a balloon catheter 10 with an improved filling mechanism compared to a situation using a single flow of filling fluid.

[0059] The conduit 30 can be coupled to the portion of the tube 14 that forms the guidewire lumen 22 within the balloon 12 in any of a number of suitable ways. For example, in one embodiment, the conduit 30 can float freely over the guidewire lumen 22 such that it is slidable in both directions along the longitudinal axis substantially along the guidewire lumen. In another embodiment, the conduit 30 is attached at one or more points along the outer surface of the tube 14 that forms the guidewire lumen 22, whether coaxial or not.

[0060] In a coaxial configuration, the conduit 30 has an internal dimension that can be slightly larger than the external dimension of the guidewire lumen 22 or tube 14a on which it is disposed. In one possible embodiment, the difference between the inner diameter of the conduit 30 and the outer diameter of the tube 14a is 0.008 inches. This configuration allows the infusion fluid to flow through the crimped stent S without significantly affecting the profile of the balloon 12 (at least until sufficient pressure is generated to cause inflation).

[0061] The length of the conduit 30 can vary and can be longer than the length of the body section or cylinder B between the cones N at the proximal and distal ends 12a, 12b. In such a case, the conduit 30 extends into the proximal and distal cones N correspondingly at its proximal and distal ends (and possibly to the point of interface with the infusion lumen, but in the illustrated embodiment the two structures are spaced apart in the longitudinal direction). Considering that each of the proximal and distal cones N has a length, in one embodiment, the conduit 30 has a length sufficient to extend into each of the proximal and distal cones to approximately the midpoint of the length of the proximal and distal cones. It should be appreciated that the length of the conduit 30 can be greater than the length E of an implant, such as a stent S, disposed over the balloon 12, but less than the length D of the balloon 12 itself. Since the stent S is compressed or crimped onto the balloon 12, the ends of the conduit 30 that extend beyond the perimeter of the stent S may tend to flare outwards, and the flared ends further contribute to providing a stent retention function during insertion and prior to deployment. However, inflation of the balloon 12 removes the compressive force, and thus the ends of the conduit 30 return to normal and do not cause any obstruction that would impede the proper deployment of the stent S.

[0062] Figures 7-9 A stent 100 is shown having a stent structure including v-shaped stent elements v1-v4 and V-shaped stent elements V1-V2, each v-shaped stent element including a first leg portion parallel to the longitudinal axis L, a peak portion, and a second leg portion angled with respect to the longitudinal axis. Starting from Figure 7 the upper left, a repeating series of stent elements is shown along the first side 66 of the stent units 62 and 64. The v-shaped stent elements v1, v2, v3, v4 are similar in shape but are oriented differently relative to the circumferential axis and / or the longitudinal axis. The V-shaped stent elements V1 and V2 face in opposite directions relative to the circumferential axis A1.

[0063] An identical repeating series of support elements (arranged identically with respect to the circumferential axis A1 and the longitudinal axis L) continues along the second side 68 of the support units 62 and 64, but offset such that the series begins with the support element v3, which is directly adjacent to v1 of the series along the first side 66. Thus, starting above Figure 7 of, the series of support elements is v3, v4, V2, v1, v2, V1, v3, etc. That is to say, the circumferential pattern can be considered as an M shape, followed by a W shape sharing a common leg with the M shape, and then repeating (also with a common leg).

[0064] The first side 66 can be connected to the second side 68 via the connector C3. For example, the support element v1 of the first side 66 can be connected to the support element v3 of the second side 68 at each distance along the circumferential axis A1, where the support elements v1 and v3 are adjacent to each other. The connector C3 is attached to the support elements v1 and v3 approximately at its peak portion to align with its first leg portion parallel to the longitudinal axis L. In the support 100, the connector C3 has a width equal to the width of the first leg portions of v1 and v3. The side of the support element adjacent to the second side 68 (towards the middle of the support 100) is connected to the second side 68 in the same manner (that is, the support elements v1 and v3 are connected by the connector C3 at the position where the peak portion of v1 is adjacent to the adjacent peak portion of v3). This pattern can continue along the length of the support 100.

[0065] It should be noted that the support elements v2 and v4 are not connected to each other by any connector when their peak portions are adjacent to each other. In other embodiments, these peak portions are connected by a connector. In still other embodiments, instead of the support 100 including only the connector C3, other connector types can be used. In still other embodiments, as an alternative or addition to connecting v1 and v3 and / or v2 and v4, the connector can connect V1 and V2. For example, in one embodiment, a straight connector can connect V1 and V2 at a position where their peak portions face away from each other (i.e., across the support unit 62). In one embodiment, the peaks connected by one or more of the connectors C3 can be in contact, such that the effective length of one or more of the connectors C3 is zero.

[0066] Figure 8The stent 100 is shown after the pattern has been cut into a tube. In one embodiment, the tube forming the stent 100 is a metal tube that has been laser machined to form a repeating series of stent elements. In one embodiment, the stent has a diameter of approximately 6 millimeters and a thickness of approximately 0.0085 inches after electropolishing. In embodiments where the stent 100 is covered by one or more graft layers, the stent 100 can be expanded to a larger diameter for coverage by the (one or more) graft layers, can be covered by the (one or more) graft layers at the cut diameter, or can be crimped to a smaller diameter for coverage by the (one or more) graft layers, followed by post-processing steps such as electropolishing.

[0067] In Figures 7-9 embodiments, the width of selected portions of the stent elements v1 - v4 tapers to a narrowed portion of the stent elements V1 - V2 to facilitate uniform expansion of the stent. Such uniform expansion is particularly preferred for stents covered by graft material to avoid tearing or deformation of the graft material when deployed. In other embodiments, as an alternative or addition to the tapering or narrowing of the width, the thickness of selected stent elements is reduced. In Figure 9 it, the widths w6 - w9 are shown at different locations on the stent unit. The width w6 is at the start of the second leg portion of the stent element v2, the width w7 is along the length of the first leg portions of the stent elements v1 and v2, the width w8 is at a section of the stent element V1, and the width w9 is at a section of the connector C3. In the illustrated embodiment, the widths w6, w7, and w9 are the same, and the width w8 is less than the widths w6, w7, and w9. It should be noted that the first leg portions and peak portions of the stent elements v1 - v4 have the same width along their lengths (i.e., w6, w7), but the second leg portion of each of the stent elements v1 - v4 tapers from the width w6 to the width w8 along its length. In one embodiment that can be used for vessel diameters from approximately 5 mm to approximately 15 mm, the widths w6, w7, and w9 are in the range of approximately 0.0070 inches to approximately 0.0120 inches, such as approximately 0.0095 inches, and the width w8 is in the range of approximately 0.0040 inches to approximately 0.0090 inches, such as approximately 0.0065 inches. For smaller or larger vessels, the dimensions can be correspondingly smaller or larger.

[0068] In Figure 9 it, the peak portions of the stent elements v1 - v4 are shown longitudinally spaced a distance D3 from the peak portions of V1 and V2, which in one embodiment at a diameter of approximately 6 millimeters is in the range of approximately 0.005 inches to approximately 0.035 inches, such as approximately 0.018 inches. In other embodiments, the peak portions are circumferentially aligned. Also in Figure 9In [the figure], the peak portions of the stent elements v2 and v4 are shown to be longitudinally spaced apart from the peak portions of the stent elements v3 and v1 by a distance D4, which in one embodiment is in the range of about 0.005 inches to about 0.035 inches, for example about 0.012 inches, at a diameter of about 6 millimeters. The distance D4 provides increased spacing of the unconnected peaks to allow additional space for expansion to better ensure that the unconnected peaks do not contact during delivery and / or deployment.

[0069] Although the invention has been described in terms of specific variations and exemplary features, those of ordinary skill in the art will recognize that the invention is not limited to the described variations or features. Additionally, where the above-described methods and steps indicate that certain events occur in a certain order, those of ordinary skill in the art will recognize that the order of some steps may be modified and such modifications are variations of the invention. Additionally, some steps may be performed simultaneously in a parallel process if possible, or sequentially as described above. Accordingly, it is also intended to cover those variations of the invention that fall within the spirit of the disclosure or the equivalents of the invention as set forth in the claims.

Claims

1. An apparatus for performing a medical procedure using a filling fluid, the apparatus comprising: An inflatable balloon having an interior for receiving the filling fluid; A first tube including a first filling lumen having a first outlet for conveying a first flow of the filling fluid to the interior of the balloon; A second tube at least partially positioned within the interior of the balloon, the second tube including a second filling lumen having a second outlet for conveying a second flow of the filling fluid to the balloon; A guide wire lumen; And A stent structure positioned exterior to the balloon and supported by the balloon; Wherein the first outlet is within the proximal cone of the balloon, and the second outlet is within the distal cone of the balloon; Wherein a larger diameter tube is used to convey the filling fluid to the distal end, and a smaller diameter tube is used to convey the filling fluid to the proximal end.

2. The apparatus according to claim 1, wherein the stent structure comprises: A series of stent elements repeating on a circumferential axis, adjacent series of stent elements being connected by a plurality of connectors, the stent elements comprising: A first V-shaped stent element having a first leg portion, a second leg portion, and a peak portion, the first V-shaped stent element having at least four different orientations; and A second V-shaped stent element connecting adjacent first V-shaped stent elements such that the second leg portion of each first V-shaped stent element is connected to the second V-shaped stent element, and the width of the second leg portion of each first V-shaped stent element tapers towards the second V-shaped stent element; Wherein the plurality of connectors are linear and connect the peak portions of selected first V-shaped stent elements of adjacent series of stent elements.

3. The device according to claim 2, wherein: The first leg portion of each first V-shaped stent element is parallel to the longitudinal axis of the apparatus.

4. The device according to claim 2, wherein: The width of the connector is equal to the width of the first leg portion of the first V-shaped stent element.

5. The apparatus according to claim 2, wherein: The peak portion of the first V-shaped stent element in a first orientation is longitudinally spaced from the peak portion of the first V-shaped stent element in a second orientation, wherein the first orientation and the second orientation are adjacent to each other.

6. The apparatus according to claim 5, wherein: The distance is in the range from 0.005 inches to 0.035 inches.

7. The device according to claim 1, wherein: The first filling lumen and the guide wire lumen are coaxial proximal to the balloon.

8. The device according to claim 1, wherein: The first tube extends into the interior of the balloon a first distance, and the second tube extends into the interior of the balloon a second distance.

9. The apparatus according to claim 8, wherein: The first tube and the second tube have different diameters.

10. The device according to claim 8, wherein: The first tube and the second tube comprise different materials.

11. The device according to claim 8, wherein: The proximal end of the second tube forming the second filling lumen is spaced from the first outlet of the first filling lumen.

12. The device according to claim 8, wherein: The stent structure is disposed on the balloon over the second tube, and wherein the second tube provides a conduit for conveying the filling fluid supplied to the proximal portion of the balloon by the first outlet of the first filling lumen to the distal portion of the balloon associated with the second outlet of the second tube such that when the balloon is inflated, the stent structure expands uniformly.

13. The device according to claim 8, wherein: The stent structure is disposed on the balloon, and wherein the second tube has a first proximal end spaced from the first outlet and the second tube is longer than the stent structure.

14. The apparatus according to claim 8, wherein: The second tube has a wall thickness in the range of 0.0005 inches to 0.0025 inches.

15. The device according to claim 8, wherein: The balloon defines a proximal cone, a distal cone, and a cylinder between the proximal cone and the distal cone, and wherein the second tube has a proximal end spaced from the first outlet and the length of the second tube is greater than or equal to the length of the cylinder.

16. The apparatus according to claim 8, wherein: The second inflation lumen does not receive inflation fluid from the first outlet of the first inflation lumen.

17. The device according to claim 1, wherein: The first outlet is proximal to the balloon.

18. The device according to claim 1, wherein: The first portion of the balloon is a proximal cone and the second portion of the balloon is a distal cone.

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