Balloon catheter system with integrated main and branched balloon components for bifurcated deployment

Abstract

A balloon catheter system is disclosed for deployment in bifurcated anatomical regions, such as vascular bifurcations. The system comprises a main balloon component on a first catheter line with proximal and distal working regions, and at least one branch balloon component on a separate catheter line with a branched working region joined to the main balloon component at a bonded section. An arcuate sealing region, which includes the bonded section, is configured to conform to the bifurcation and enhance sealing. Each catheter line is independently configured for inflation or guidance of its respective balloon component, allowing precise expansion within a main vessel and one or more branch vessels. Additional embodiments provide for multiple branch balloons, independent inflation control, support sleeves, and radiopaque markers to facilitate deployment and positioning. The system addresses challenges in treating complex bifurcated anatomy with improved conformity, stability, and procedural flexibility.

Description

BALLOON CATHETER SYSTEM WITH INTEGRATED MAIN AND BRANCHED BALLOON COMPONENTS FOR BIFURCATED DEPLOYMENTFIELD OF THE INVENTION

[0001] This Invention relates to a balloon catheter, particularly one with integrated main and branched balloons for bifurcated deployment in the human body.BACKGROUND TO THE INVENTION

[0002] Balloon catheters are widely used across multiple medical disciplines for various therapeutic and diagnostic procedures. In interventional cardiology, they are essential for coronary angioplasty and stent deployment. Neurovascular applications include intracranial vessel dilation and embolic coil remodelling. Structural heart procedures employ specialized balloons for valve preparation and implant deployment. In peripheral vascular interventions, balloons are used for both arterial and venous applications, Including deep vein thrombosis treatment and venous stenting. Gastrointestinal and pulmonary medicine utilise balloon dilation for strictures and stenoses. Additionally, balloon catheters find applications in ENT procedures and other specialised Interventions throughout the body.

[0003] The fundamental design of balloon catheters typically follows one of two approaches: co-axial or multi-lumen construction. Co-axial designs feature two or more concentric tubes where the inner lumen accommodates a guidewire while the outer annular space between the two or more concentric tubes provides inflation access to the balloon. Multi-lumen configurationsincorporate multiple parallel channels within a single catheter body or shaft, separately serving guidewire passage and balloon inflation. Each design presents distinct advantages and limitations regarding trackability, profile, and manufacturing complexity.

[0004] A critical requirement for all balloon catheters is transitioning between a low-profile, un-inflated delivery state and an expanded therapeutic state when inflated. Initial crossing profiles must be minimised to facilitate passage through introducer sheaths, tortuous vessels, and stenotic lesions. Yet these same devices must reliably expand to several times their initial diameter to perform therapeutic work, such as vessel dilation or stent deployment.

[0005] Bifurcated vessels, where a main vessel branches into two or more smaller vessels, present unique challenges for endovascular treatment. Such anatomical structures are commonly found throughout the human vasculature, including in both arterial and venous systems. Treatment of disease or defects at these bifurcation points often requires specialized devices capable of conforming to the complex three-dimensional anatomy. These devices include implants like stents and stent-grafts which must maintain adequate blood flow to both the main vessel and branch vessels.

[0006] Conventional balloon catheters typically comprise a single inflatable balloon mounted on a catheter shaft, with the balloon configured to expand radially when inflated to dilate a target vessel segment. However, when treating bifurcated vessels, single balloon catheters are often inadequate as they cannot simultaneously address both the main vessel and branch vessel anatomy. Thislimitation has led to the development of specialized bifurcation balloon catheters.

[0007] Existing bifurcation balloon catheter designs have several drawbacks. Many require complex manufacturing processes, resulting in devices with large crossing profiles that are difficult to deliver through tortuous anatomy. Some designs incorporate rigid junction points between main and branch portions that limit conformability. Others lack independent control of main and branch balloon inflation, preventing optimal treatment of asymmetric lesions. Additionally, current designs may not adequately address the anatomical variation found at vessel bifurcations, particularly in cases where the branch vessel exits the main vessel at acute or obtuse angles.

[0008] The challenge of treating bifurcated vessels is particularly evident in procedures requiring staged interventions. Pre-dilation often demands precise balloon positioning and sizing to prepare both main and branch vessels without compromising side branch access. During stent deployment, especially with bifurcated stent-grafts, simultaneous or sequential balloon inflation may be necessary to ensure proper expansion and wall apposition. Post-dilation procedures frequently require specialized balloon shapes to optimize stent expansion at the bifurcation carina and ostium.

[0009] In venous applications, bifurcation balloon catheters must address unique challenges including vessel compliance, irregular geometry, and the presence of valves. Common procedures include dilation of chronic venous occlusions at confluence points, treatment of May-Thurner syndrome involvingthe iliac vein bifurcation, and optimization of venous stents across junctions such as the common femoral vein bifurcation.

[0010] Furthermore, when treating bifurcated vessels with implants such as stents or stent-grafts, conventional balloon catheters may not provide adequate expansion and apposition of the implant, particularly at the junction point between main and branch vessels. This can lead to incomplete sealing, endoleaks, or other complications that may compromise treatment outcomes. The challenge is magnified in cases requiring conformance to complex anatomical geometries, such as in arch vessel treatment during thoracic endovascular repair or renal artery stenting during abdominal aortic procedures.

[0011] There remains a need for improved bifurcation balloon catheters that can effectively treat complex bifurcated vessel anatomy while maintaining a low crossing profile, high flexibility, and precise control over balloon inflation. Such devices should ideally be compatible with a wide range of bifurcation angles and anatomical variations while being relatively simple to manufacture and use.

[0012] The invention at least partially addresses the aforementioned problems.SUMMARY OF INVENTION

[0013] Hereinafter, “component” refers to a discretely inflatable balloon unit.

[0014] Hereinafter, the term “expand” encompasses the actions of dilation and dilatation.

[0015] Hereinafter, the term “bifurcated area” is not limited to a vascular bifurcation but also includes a bifurcated implant, sinus, atrium, or similar anatomical structures.

[0018] The invention provides a balloon catheter system with integrated main and branched balloon components for deployment to a bifurcated area, the system includes:a main balloon component on a first catheter line having a working region comprised of a proximal working region and a distal working region, a first branch balloon component on a second catheter line having a branched working region and joined to the main balloon component at a bonded section,a first arcuate sealing region which includes or comprises the bonded section,wherein the first and the second catheter lines are adapted to inflate or guide the main and the first branch balloon components, respectively.

[0019] The first branch balloon component may be joined to the main balloon component within the proximal working region.

[0020] The first arcuate sealing region may be configured to expand to conform to a first bifurcated area.

[0021] The proximal working region, the distal working region and the branched working region may be configured to expand to conform to a proximalsection of a main vessel, a distal section of the main vessel, and a peripheral vessel, respectively, adjacent to the first bifurcated area.

[0022] The first branch balloon may project from the bonded region in a first direction.

[0023] The first direction may be a medial or lateral or divergent direction relative to the main balloon component.

[0024] The medial or lateral direction may be a posterolateral direction or an anterolateral direction.

[0025] The system may include a second branch balloon component on a third catheter line.

[0026] The second branch balloon component may be joined to the main balloon component within the proximal working region about a second bonded section.

[0027] The system may include a second arcuate sealing region, which includes or comprises the second bonded section.

[0028] The second arcuate sealing region may be configured to expand to conform to a second bifurcated area

[0029] The third catheter line may be adapted to inflate or guide the second branch balloon component independently of the main or the first branch balloon component.

[0030] The second branch balloon may project from the second bonded region in a second direction.

[0031] The second direction may be a posterolateral or anterolateral direction or a posteromedial or anteromedial direction.

[0032] The system may comprise a first sealing balloon operatively coupled to at least the first branch balloon component along the first arcuate sealing region, configured to enhance the sealing functionality within the sealing region.

[0033] The system may comprise a second sealing balloon operatively coupled to at least the second branch balloon component along the second arcuate sealing region, configured to enhance the sealing functionality within the sealing region.

[0034] These balloons are bonded to each other for a portion of the working length of the main balloon, using adhesives or a thermal bond or a brace / strap on this bonded section may be covered by an outer braid or an outer restraining sleeve to ensure a cylindrical shape when one or both balloons are inflated.

[0035] Anyone or more of the proximal working region, the distal working region, the first or second sealing region and the branched working region may be covered over a covered section with a restraining sleeve or a braid, integrated with an outer surface of each region, to limit the expansion, or the burst pressure, of the respective balloon component about the covered section.

[0036] The balloon catheter system may further comprise a support sleeve coupled to the main balloon component and extending at least partially over the first bonded section and / or the second bonded section.

[0037] The balloon components may be made from one or more of the following: a thermoplastic polyurethane (TPU), a thermoplastic elastomer (TPE), polyether block amide (PEBAX), polyethene terephthalate (PET) and Nylon 12 (PA12).

[0038] The guidewire lumens or guide-lines may include a radio-opaque marker band made from Platinum or Iridium another metal or metal-alloy with high radio-opacity when imaged under x-ray. These marker bands are usually positioned within each balloon component and on the outer-surface of the guideline, positioned axially to align with the proximal end and the distal end of each working region or sealing region of each balloon. The marker bands assist in the positioning of the balloon component prior to inflation, such that it crosses the target anatomy or stricture or implant delivery site, as is customary with many existing balloon catheters and as is familiar to those in the balloon catheter industry.BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The invention is further described by way of examples, with reference to the accompanying drawings in which:Figure 1 is an isometric view of a balloon catheter system in accordance with a first embodiment of the invention,Figure 2 is view in elevation of the first embodiment of Figure 1,Figure 3 is an isometric view of a second embodiment of the balloon catheter system of the invention,Figure 4 is view in elevation of the second embodiment of Figure 3, Figure 5 is a view in elevation of a third embodiment of the invention, Figures 6 to 9 are isometric views of a fourth, fifth, sixth and seventh embodiments, respectively of the invention,Figure 10 is an isometric view of an eighth embodiment of the invention, Figure 11 is a view in the longitudinal section of the eighth embodiment, Figure 12 is a view in the longitudinal section of the ninth embodiment, Figure 13 is a view in the longitudinal section of the tenth embodiment, and Figure 14 is an isometric view of the first embodiment of the system with a bracing sleeve.DESCRIPTION OF PREFERRED EMBODIMENT

[0040] Figures 1 to 13 illustrate various embodiments and arrangements of a balloon catheter system (respectively designated 10.1 to 10.10), each of which accords with the invention.

[0041] Referring to Figures 1 and 2, and a first embodiment, the balloon catheter system 10.1 includes a main balloon component 12, mounted on a first catheter line 14, and a first branch balloon module component 16, mounted on a second catheter line 18.

[0042] The first and second catheter lines (14, 18) are flexible tubular structures that extend from respective distal ends (20, 22) to one or more proximal ends (not shown) at a hub. These lines may remain separate alongtheir entire length, as illustrated, or merge into a single catheter tube near the proximal end. Each catheter line is configured with inflation channels to inflate the components, either simultaneously or independently, and working channels that allow main and branch guidewires to pass for guidance of each component.

[0043] The hub (not shown) can be configured to provide access to the inflation channels and working channel passages. Each balloon is connected to a dedicated inflation port near the proximal end of the balloon catheter. This configuration enables the working portion of the balloon to be inflated externally, consistent with standard over-the-wire balloon catheter designs.

[0044] Both the main and branched balloon components (12, 16) are formed from a flexible envelope, preferably made of a homogeneous material such as thermoplastic polyurethane (TPU), thermoplastic elastomer (TPE), polyether block amide (PEBAX), polyethene terephthalate (PET), or Nylon 12 (PA12). The envelope is sealably affixed to the respective catheter lines (14, 18) at a proximal neck 24 and a distal neck 26 (designated only on the main balloon for ease of illustration), enveloping an inflation outlet (not shown) in the respective catheter line, through which an inflation medium passes from the catheter line into the balloon component to inflate the balloon component when positioned and ready for deployment.

[0045] Each balloon component includes a proximal cone 28.1 and a distal cone 30, extending from the proximal and distal necks, respectively (designated only on the main balloon for ease of illustration). Between these cones, a cylindrical working region is defined when the balloon is inflated.

[0046] The working region of the main balloon component 12 is divided both notionally and functionally into a proximal working region 32 and a distal working region 34. However, for the branched balloon component 16, no such notional division is required, and the working region is defined as a branched working region 36.

[0047] The balloon components are shown in an inflated state in the Figures, illustrating their configuration at the target location, a bifurcated area. In this configuration, the balloons are inflated so that the working regions expand and contact the anatomical areas within and around the bifurcated region to perform their intended function.

[0048] The first branch balloon component 22 is attached to the main balloon component within the proximal working region 32 of the main balloon. In this example, the first branch balloon component is joined to the main balloon component at its proximal cone 28.2, with the balloon module walls of both the main and branched balloon components remaining distinct yet conjugated along a bonded section 38.

[0049] The balloon components (12, 16) are bonded together using adhesives, a thermal bond, a radiofrequency bond or a brace or strap.

[0050] In this configuration, the junction between the main balloon component 12 and the first branched balloon component 16, which includes the bonded section 38, forms a first arcuate or circumferential sealing region 40. This sealing region is partly defined by the bonded section, which marks an origin of the region, and extends along the outer cylindrical surface of the branchedballoon component. The sealing region is illustrated in Figure 1, outlined with a dotted line and labelled as 40.

[0051] As shown in Figure 14, the balloon catheter system may include a bracing sleeve 41. While the sleeve is depicted in connection with the first embodiment, it can be incorporated into any embodiment of the invention. The bracing sleeve is positioned at least partially over the sealing region to provide mechanical reinforcement to this area and the bonded section 38, helping to maintain a circular cross-section when the main and branched balloons (12, 16) are inflated to high pressures. The sleeve can be attached to the outer surface of the main balloon or both the main and branched balloons using either an adhesive or a thermal bond.

[0052] The proximal cone provides an angled contact surface in this configuration, causing the first branch balloon to project anterolaterally from the main balloon component. This arrangement mimics the anatomy of a bifurcated vascular area 42 where the balloon catheter system 10.1 will be deployed, where a peripheral vessel 44 will often branch off a main vessel 46 (see Figure 13) in an anterolateral direction.

[0053] Figures 3 and 4 illustrate a second embodiment of the invention, the balloon catheter system 10.2. In describing this and subsequent embodiments, features that share similar designations will not be repeated in detail. Instead, the description focuses primarily on the fundamental differences between this embodiment and those previously described.

[0054] This embodiment 10.2 differs from the preceding embodiment 10.1 in that the main balloon component 12 and the branched balloon component 16 are more extensively integrated along a longer bonded section 38. Externally, it appears that the main balloon component shares the proximal working region 32 and the proximal cone 28 with the branched balloon component. However, this region is internally divided between the two components by wall 42, which also defines the bonded section. The first branch balloon component diverges from the axial direction of the main balloon component only halfway along its length, extending anterolaterally. This configuration allows for the branch guidewire lumen and the branch guidewire to bend with a larger bend-radius the bifurcation compared to the first embodiment.

[0055] A third embodiment, referred to as the balloon catheter system 10.3, is depicted in Figure 5. Similar to embodiment 10.1, the first branched balloon component 16 is a separate structure joined to the proximal cone of the main balloon component. In this embodiment, a second branched balloon component 44 is also included, mirroring the shape and configuration of component 16. The two branched balloon components extend in opposite anterolateral directions, each positioned out of the plane of the other. Both components are mounted on respective catheter lines (18.1 and 18.2) to enable inflation and / or guidance. This configuration is designed to accommodate a bifurcated vascular region 42, where adjacent peripheral vessels branch from the main vessel in opposing directions.

[0056] The balloon catheter system 10.4, shown in Figure 6, incorporates a single (first) branched balloon component 16 that extends in reverse,posterolateral direction, distinguishing it from previous embodiments. The corresponding second catheter line follows a gentle curve or an optimised bend radius, tracing a curve or helix along the outer cylindrical surface of the main balloon component 12. This design ensures efficient navigation through the vascular system and minimises stress on the catheter line and guidewire during deployment. This configuration is ideal for treating bifurcations that include posterolateral vessels, essential for perfusing posterior and lateral tissues despite their non-alignment with primary blood flow.

[0057] The balloon catheter system 10.5, shown in Figure 7, is similar to system 10.6, with the main difference being integrating the first branched balloon component 16. In this design, the branched balloon component is merged with the main balloon component along a portion of its working region rather than being a separate structure attached to a small section of the proximal cone 28.2. Using blow-moulding to form this section reduces the wall thickness, making the deflated system more compact and flexible, thereby reducing the crossing profile and ensuring good performance during deployment.

[0058] The integrated "double-back" section 48 (shown in dotted outline in Figure 7) has a thin wall thickness, which minimises the crossing profile when the system is deflated. This design is advantageous over earlier embodiments, as it reduces the risk of kinking or bending in the catheter inflation or guidewire or guidewire lumen to the branched balloon component, improving deployment.

[0059] The embodiment 10.6, shown in Figure 8, retains the integrated feature of the main balloon component 12 and the branched balloon component 16, similar to the previously described embodiment. However, in this case, insteadof the branched balloon wrapping around and extending toward the proximal end of the main balloon component, the branched balloon component extends anterolaterally along the second catheter line 18. The proximal portion of the component’s working length follows a helical pattern across the proximal working region 32 of the main balloon component.

[0060] As with the earlier embodiment, guidewires (50, 52) extend from the distal tips (20, 22) of the main balloon component 12 and the first branched balloon component 16. This dual-guidewire arrangement ensures precise control and positioning, especially when navigating complex anatomical regions. The distal tips ensure improved trackability during insertion and navigation to the target inflation site. For example, they may be made from a soft polymer like Polyurethane 80A or Pebax 55D to provide an atraumatic tip.

[0061] The balloon catheter system 10.7, shown in Figure 9, features a sealing balloon component 54 that connects the first branched balloon 16 and the main balloon component at a junction, which defines the sealing region 40.

[0062] The sealing balloon component 54 may be a stretchy or compliant balloon made from a softer material than the main and branched balloon components, such as PEBA, TPU, or TPE, as these materials are more suitable for moulding and sealing functions. The component will have a very thin wall thickness, essential for maintaining a small crossing profile when deflated, allowing for easier insertion into the body and smooth tracking to the target inflation site.

[0063] This sealing balloon component 54 is independently inflated through its catheter line 56, separate from the main and branched balloon components. When inflated, it enhances the sealing functionality within the sealing region.

[0064] Figures 10 and 11 depict an alternative embodiment of system 10.8, in which the main and branched balloon components (12, 16) are symmetrical. The two components are connected by an extended bonded region that initially aligns with the main balloon component within the proximal working region 32. This region then diverges around the sealing region 40, extending into the distal working region 34 of the main balloon component 12 and the branched working region 36 of the branched balloon component.

[0065] The penultimate embodiment of the balloon catheter system 10.9, shown in Figure 12, features an approximately circular hole created in the main balloon component 12 wall within the proximal working region 32. The branched balloon component, with its proximal section removed, passes through this hole. The truncated proximal end of the branched balloon component is then sealed around the hole, forming an annular bonded region 38.

[0066] This annular bonded region ensures that the main balloon and the branch balloon components are sealably connected and are in fluid communication with one another. In this embodiment, both balloon components are inflated via one inflation line. Each balloon component has a distinct guidewire lumen and a dedicated guidewire. This embodiment allows significant space within the balloon components for each guidewire to bend with a large bend radius, which is advantageous in minimising the stress within theguidewire lumen and also the force required to advance the balloon components through tortuous anatomy during positioning.

[0067] Figure 13 illustrates the final embodiment 10.10. This embodiment differs from the previous ones in that the branched balloon component 16 remains intact. The component penetrates the hole in the main balloon component, passing from the inside to the outside. It is then sealed around the hole and at a point approximately midway along its working length. As a result, the working length of the branched balloon component is divided into two portions: one that remains within the main balloon component, and the other, the branched working region 36, which projects anterolaterally from the main balloon component.

[0068] During deployment, the balloon components are deflated and advanced through the vessel using guidewires correctly positioned to traverse the target dilation site. The guidewires primarily control the path and may follow a straight trajectory or a tight-radius curved bend. Due to the thin profile of the balloon components — achieved through the blow moulding process — their flexibility when deflated allows them to conform closely to the guidewires' path without exerting significant bending moments or forces on them. This flexibility ensures smooth navigation and minimal resistance during advancement.

[0069] The balloon components of the system can be made of the same or of different materials as may be needed to optimise compliance and inflation pressures / dilation force for each.

[0070] Any embodiments described above are adapted to di latate the anatomy for the delivery and dilation of implants or stents, or the post-dilation or moulding of implants or stents within a bifurcation area. The embodiments are all pre¬ formed to approximate the anatomy in and around a bifurcation area.

[0071] The bifurcation area in vessels is often non-tubular or non-cylindrical, requiring more complex balloon shapes for effective treatment. A conical balloon can better approximate a bifurcated vessel's anatomy than a cylindrical balloon. However, inflating balloons within conical-shaped anatomy, strictures, or implants poses a challenge: during inflation, the balloon may "watermelon pip" out of position. This occurs because the inward radial force from the anatomy, strictures, or implants includes an axial vector component, propelling the balloon axially, often toward the area with a larger cross-section or opening, and away from the target deployment site. The bifurcated balloon can counteract these axial forces during inflation by utilising a bifurcated balloon instead of one or more cylindrical or conical balloons. This stability helps the balloon maintain its position throughout the inflation cycle, minimising the risk of unwanted axial displacement and reducing the likelihood of exerting unintended force on the target anatomy, strictures, or implants.

Claims

CLAIMS1. A balloon catheter system for deployment to a bifurcated area, comprising:a main balloon component on a first catheter line with proximal and distal working regions,a first branch balloon component on a second catheter line with a branched working region and joined to the main balloon component at a bonded section,a first arcuate sealing region which includes the bonded section, wherein the first and the second catheter lines are configured to inflate or guide the main and the first branch balloon components, respectively.

2. A balloon catheter system according to claim 1 wherein the first arcuate sealing region is configured to expand to conform to a first bifurcated area.

3. A balloon catheter system according to claim 1 or 2 wherein the proximal working region, the distal working region and the branched working region are configured to expand to conform to a proximal section of a main vessel, a distal section of the main vessel, and a peripheral vessel, respectively, adjacent to the first bifurcated area.

4. A balloon catheter system according to anyone of claims 1 to 3 wherein the first branch balloon projects from the bonded region in a first direction which is either a lateral direction or a divergent direction relative to the main balloon component.

5. A balloon catheter system according to claim 4 wherein the lateral direction is a posterolateral direction or an anterolateral direction.

6. A balloon catheter system according to anyone of claims 1 to 5 wherein the system includes a second branch balloon component on a third catheter line.

7. A balloon catheter system according to claim 6 wherein the third catheter line is configured to inflate or guide the second branch balloon component independently of the main or the first branch balloon component.

8. A balloon catheter system according to claim 6 or 7 wherein the second branch balloon component is joined to the main balloon component within the proximal working region about a second bonded section.

9. A balloon catheter system according to claim 8 which includes a second arcuate sealing region, which includes the second bonded section.

10. A balloon catheter system according to claim 9 wherein the second arcuate sealing region is configured to expand to conform to a second bifurcated area.

11. A balloon catheter system according to claims 8 to 10 wherein the second branch balloon projects from the second bonded region in a second direction.

12. A balloon catheter system according to claim 11 wherein the second direction is a posterolateral direction or an anterolateral direction.

13. The balloon catheter system of any preceding claim, further comprising a support sleeve coupled to the main balloon component and extending at least partially over the first bonded section and / or the second bonded section.

Images