Description:IMPROVED SCORING BALLOON CATHETER WITH THERAPEUTIC COATING AND METHOD OF MANUFACTURE
FIELDOF INVENTION
The present disclosure relates to medical devices, particularly balloon catheters used in angioplasty procedures for treating vascular diseases such as atherosclerosis. More particularly, the present disclosure relates to scoring balloon catheters incorporating specialized scoring elements designed to modify pathological tissue while minimizing vascular trauma.

BACKGROUND
Conventional scoring and cutting balloon catheters employ rigid metallic blades or scoring elements to modify pathological tissue or tissues (e.g., plaque or lesions) within blood vessels. While these devices can effectively fracture plaque, they often cause unintended trauma to the vessel wall due to their sharp edges or excessive contact pressure. Additionally, existing designs may suffer from poor flexibility, limiting their ability to navigate tortuous anatomy, or from insufficient structural integrity, leading to detachment of scoring elements during inflation. Drug-coated balloons have been introduced to reduce restenosis, but their combination with scoring mechanisms presents challenges in maintaining drug integrity and uniform delivery. Furthermore, traditional attachment methods for scoring elements, such as adhesives or mechanical fasteners, may fail under repeated balloon expansion cycles. These limitations highlight the need for improved scoring balloon catheter designs that balance effective plaque modification with enhanced safety, deliverability, and durability. Advances in this field could address unmet clinical demands for more reliable and minimally traumatic interventional solutions.

SUMMARY
It is therefore an object of the present disclosure to provide an improved scoring balloon catheter for angioplasty procedures, which integrates specialized scoring elements with enhanced safety and drug delivery capabilities, thereby overcoming limitations of prior art devices such as excessive vessel trauma, poor flexibility, and unreliable attachment mechanisms.

This object is achieved by the features of the independent claims. Further implementation forms are apparent from the dependent claims and the description.

According to a first aspect, a scoring balloon catheter is provided. The catheter comprises a catheter shaft for intravascular delivery, an expandable balloon coupled to the shaft, and at least one elongate scoring element disposed on the outer surface of the balloon. The scoring element features a substantially convex, tissue-engaging top surface configured to dilate the vessel wall and apply focal force to pathological tissue upon balloon expansion, enabling controlled scoring while minimizing trauma. The scoring element is securely affixed to the balloon via a robust attachment mechanism to withstand inflation and deflation cycles.

According to a second aspect, a method of manufacturing the scoring balloon catheter is provided. The method comprises fabricating the scoring element with a predetermined cross-sectional profile, welding it to the balloon, and applying a therapeutic agent to the assembly.

Preferably, the scoring element is substantially semi-cylindrical or D-shaped in cross-section, with a flat side integrally abutting the balloon surface and a curved tissue-contacting surface.

Optionally, the cross-sectional profile of the scoring element may be selected from crescent, parabolic, or semi-elliptical shapes to optimize plaque modification.

Preferably, a therapeutic agent is applied to the balloon or scoring element, the agent selected from the group consisting of Sirolimus, Paclitaxel, Everolimus, or a polymer-free antiproliferative drug.

Optionally, the therapeutic agent is delivered via a nanotechnology-based carrier configured for controlled elution.

Preferably, the scoring element is affixed to the balloon using one or more welding techniques selected from laser welding, ultrasonic welding, or thermal fusion.

Preferably, the scoring element comprises a polymer-jacketed core to enhance biocompatibility and prevent vessel laceration.

These and other aspects of the present disclosure will be apparent from the detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.
FIG. 1 shows complete Balloon Assembly in accordance with an embodiment of the invention.
FIG. 2 (a, b) shows cross-sectional view of the scoring balloon catheter illustrating internal and external geometry and its associated scoring members.

FIG. 3 is a flowchart illustrating the sequential steps for manufacturing the scoring balloon catheter.
Fig. 4 is a cross-sectional profile of a scoring member, showing its flat surface that is to be bonded to the balloon, convex tissue-engaging surface, and applied therapeutic coating layer.
Fig. 5 (a,b) shows drug coating to the balloon’s exposed surface between the scoring elements.
The figures depict embodiments of the present subject matter for the purposes of illustration only. A person skilled in the art will easily recognize from the following description that alternative embodiments of the device and process illustrated herein may be employed without departing from the principles of the disclosure described herein.

DETAILED DESCRIPTION
The present disclosure may be modified in various ways and implemented by various embodiments, so that specific embodiments are shown in the drawings and will be described in detail. However, the present disclosure is not limited to the specific embodiments, but may include all modifications, equivalents and substitutions within the scope of the present disclosure.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

It will be further understood that the terms "comprises", "comprising", "includes", and/or "including" when used herein, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms used herein should be interpreted as having a meaning that is consistent with their meaning in the context of this specification and the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

Herein, with reference to the accompanying drawings, embodiments of the present disclosure will be described in detail. Prior to the description, it should be understood that the terms used in the specification should not be construed as limited to general and dictionary meanings, but interpreted based on the meanings and concepts corresponding to technical aspects of the present disclosure on the basis of the principle that the inventor is allowed to define terms appropriately for the best explanation.

In addition, technical terms and scientific terms used in the present specification have the general meaning understood by those skilled in the art to which the present disclosure pertains unless otherwise defined, and a description for the known function and configuration obscuring the present disclosure will be omitted in the following description and the accompanying drawings. The drawings to be provided below are provided by way of example so that the idea of the present disclosure can be sufficiently delivered to a person skilled in the art to which the present disclosure pertains. Therefore, the present disclosure is not limited to the drawings provided below but may be modified in many different forms. In addition, like reference numerals designate like elements throughout the specification. In the drawings, same reference numerals denote same components throughout the disclosure.

Implementations of the present disclosure provide an improved scoring balloon catheter for angioplasty procedures, integrating specialized elongate scoring elements with a substantially convexly curved top surface, preferably semi-cylindrical or D-shaped in cross-section, securely affixed to an expandable balloon, and incorporating a therapeutic coating to enhance procedural outcomes. The catheter includes a catheter shaft for intravascular delivery, a biocompatible polymer balloon, and at least one scoring element configured to apply focal force to pathological tissue, such as calcified or fibrotic plaque, while minimizing vessel trauma. Methods for manufacturing the catheter, including fabricating the scoring element, welding it to the balloon, and applying a therapeutic agent, are also provided. To make the details of the present disclosure more comprehensible for a person skilled in the art, the following implementations are described with reference to the accompanying drawings.

Terms such as “a first,” “a second,” “a third,” and “a fourth” (if any) in the summary, claims, and foregoing accompanying drawings of the present disclosure are used to distinguish between similar components or features and are not necessarily used to describe a specific sequence or order. It should be understood that the terms so used are interchangeable under appropriate circumstances, so that the implementations of the present disclosure described herein are, for example, capable of being implemented in configurations other than those illustrated or described herein. Furthermore, the terms “include,” “comprise,” and “have” and any variations thereof, are intended to cover a non-exclusive inclusion. For example, a device, a system, a method, or a component that includes a series of elements or steps is not necessarily limited to expressly listed elements or steps but may include other elements or steps that are not expressly listed or that are inherent to such device, system, method, or component.

The present disclosure pertains to an improved scoring balloon catheter designed for angioplasty procedures, particularly for treating vascular diseases such as atherosclerosis by modifying pathological tissue or tissues (e.g., plaque or lesions) build up within the blood vessel while minimizing trauma to the vessel wall. This scoring balloon catheter integrates specialized elongate scoring elements with a substantially convex top surface, preferably semi-cylindrical or D-shaped in cross-section, securely affixed to an expandable balloon via advanced welding techniques. The catheter further incorporates a therapeutic coating to reduce restenosis, delivering agents such as Sirolimus, Paclitaxel, Everolimus, or polymer-free antiproliferative drugs, optionally via nanotechnology-based carriers for controlled elution. The design ensures enhanced flexibility, deliverability, and durability, addressing limitations of conventional scoring and cutting balloon catheters, such as excessive vessel trauma, poor navigation in tortuous anatomy, and unreliable attachment of scoring elements.

The scoring balloon catheter comprises a catheter shaft configured for intravascular delivery within a blood vessel, an expandable balloon coupled to the distal end of the shaft, and a plurality of elongate, parallel scoring elements disposed on the outer surface of the balloon. The catheter shaft is a flexible, tubular structure, typically constructed from biocompatible materials such as nylon or polyethylene, with one or more lumens to facilitate guidewire passage and balloon inflation. The balloon, constructed from a biocompatible polymer material such as polyurethane or nylon, is designed to ensure flexibility and durability during expansion within the blood vessel. The balloon’s outer surface serves as the platform for the scoring elements, which are critical to the catheter’s plaque-modifying function.

The elongate scoring element is a key feature, engineered to apply contact-induced focal force to pathological tissue, such as calcified or fibrotic plaque, resulting in controlled scoring. Each scoring element features a cross-sectional profile with a bottom external surface, which is flat and configured to integrally about the outer surface of the balloon, and a top outwardly curved external surface, which is substantially convex and configured to dilate the interior vessel wall and score pathological tissue upon balloon expansion. Preferably, the scoring element is substantially semi-cylindrical or D-shaped in cross-section, with the flat side bonded to the balloon and the curved tissue-engaging surface optimized to prevent deep arterial cuts. This D-shaped configuration enhances focal force application, enabling effective plaque modification while minimizing trauma to the vessel wall’s anatomical layers. Alternative cross-sectional profiles may be employed, including crescent, parabolic, tear-drop, semi-elliptical, asymmetrical ridge, or curved hybrid profiles, to optimize scoring performance based on specific clinical requirements. The scoring element comprises a core, typically a semi-rigid material such as a biocompatible metal (e.g., nitinol or stainless steel) or reinforced polymer, lined with a polymer jacket. The polymer jacket, made from materials such as polyurethane or silicone, enhances biocompatibility and prevents vessel wall laceration by providing a smooth, protective interface between the scoring element and the vascular tissue.

The scoring element is securely affixed to the balloon surface using a robust attachment mechanism designed to maintain structural integrity during repeated inflation and deflation cycles. The attachment is achieved through one or more welding techniques, including laser welding, ultrasonic welding, radiofrequency (RF) welding, thermal fusion, or combinations thereof. These advanced welding technologies ensure a strong bond between the flat bottom surface of the scoring element and the polymer balloon, preventing detachment or displacement under the mechanical stresses of balloon expansion. The welding process is precisely controlled to maintain the balloon’s flexibility and inflation dynamics, ensuring that the scoring elements remain firmly integrated without compromising the catheter’s deliverability or durability. In preferred embodiments, the plurality of scoring elements is disposed longitudinally along the balloon surface, spaced evenly to distribute focal force uniformly and enhance plaque modification across the lesion.

The catheter incorporates a drug-delivery mechanism to improve post-procedural outcomes by reducing restenosis, the re-narrowing of the treated vessel. A therapeutic agent is applied to the balloon, the scoring element, or both, using specialized deposition techniques to ensure uniform coverage and optimal retention. The therapeutic agent is selected from the group consisting of Sirolimus, Paclitaxel, Everolimus, or a polymer-free antiproliferative agent, chosen for their proven efficacy in inhibiting neointimal hyperplasia. The drug may be applied with or without a nanotechnology-based carrier, such as nanoparticles or nanogels, which enhances controlled drug elution by regulating the release profile to maximize therapeutic effect. Polymer-free options are also supported, allowing direct application of the antiproliferative agent to the balloon or scoring element without a polymer matrix, which may reduce long-term inflammatory responses. The drug coating ensures effective vascular healing by delivering the therapeutic agent directly to the vessel wall during balloon expansion, where the scoring elements facilitate localized drug penetration into the scored plaque.

FIG. 1 presents an isometric view of the complete Drug-Eluting Balloon (DEB) scoring balloon catheter. The central component of the structure is the polymer balloon 102 to ensure flexibility and robustness during angioplasty procedures. Surrounding the outer surface of this balloon are four scoring elements 104, strategically and evenly distributed around the circumference. Each scoring element is securely welded onto the balloon surface. Further the therapeutic coating layer 110 is clearly marked along the surface of the balloon and encompasses the entire active area of the catheter. The figure illustrates the critical geometric and functional features of the assembly, including the balloon’s inflation profile, the longitudinal alignment of the scoring wires, and the therapeutic coating layer for effective plaque modification, vessel expansion, and enhanced healing outcomes during interventional cardiology procedures.

FIG. 2 presents a cross-sectional view of the scoring balloon 100 of the scoring balloon catheter, to reveal its internal and external geometry. The figure illustrating the cross-sectional arrangement and key components of the balloon 102 and its associated scoring elements 104. FIG. 2 depicts a circular cross-section of the expandable balloon 102 represents the outer diameter of the balloon which is 2 mm to 4mm. Further, the balloon length is 8mm to 16mm, constructed from a durable and biocompatible polymer material such as Nylon, with a measurable wall thickness designed to provide both structural integrity and flexibility during inflation, with multiple scoring elements 104 disposed evenly around its outer surface at 90-degree intervals, creating a symmetric, circumferential distribution intended to ensure uniform contact with the vascular plaque during expansion. Each scoring element 104 have precise geometry and interface features. The scoring element 104 exhibits a D-shaped cross-sectional or semi-flat profile, as further detailed in FIG. 4, with the flat bottom surface 106 integrally abutting the outer surface of the balloon 102 i.e height relative to the balloon wall and the substantially convex top surface 108 configured to engage the vessel wall and pathological tissue during balloon expansion. Further, a counter cut is incorporated at the base edge of each scoring element 104 to optimize clinical functionality of the scoring balloon catheter 102. This cut (C) represents (in Fig. 2a) a curvature where the D-shaped scoring wire 104 transitions into the bonding interface with the balloon wall 102. The D-shaped cross-section, visible in both FIGs. 1 & 2, highlights the scoring element’s 104 design to apply focal force at targeted points on the arterial wall for plaque modification while preventing deep arterial cuts/cracks, ensuring controlled scoring as the balloon 102 dilates the vessel. These scoring elements are composed of stainless steel (SS) or Nitinol.

In an embodiment, the radius of counter cuts are 0.04mm.

In an embodiment, the tip shape of the scoring element can be rounded, beveled, or knife-edged important for determining the depth and style of lesion modification and the radius of D-shape wire is 0.15mm.

In an embodiment, the reference vessel diameter (RVD) is 2 mm to 4 mm.

A polymer jacket lines each scoring element 104, as indicated by the coating layer surrounding the D-shaped wires in FIG. 1 and further illustrated in FIG. 4 as the therapeutic coating layer 110, enhancing biocompatibility and preventing vessel wall laceration by providing a smooth, protective interface. The alignment of therapeutic coating layer 110 over the balloon's active surface reinforce the dual functionality of mechanical modification and drug delivery. The scoring elements 104 are securely welded or bonded to the balloon 102 surface using advanced joining methods such as laser welding, ultrasonic welding, RF welding, or thermal fusion, thereby ensuring robust attachment that withstands the mechanical stresses of inflation and deflation cycles. The therapeutic coating layer 110, shown in FIG. 4 as applied on the scoring element 104 and represented in FIG. 1 as part of the coating layer, covers the balloon 102 and/or scoring elements 104, delivering agents such as Sirolimus, Paclitaxel, or Everolimus to improve post-procedural vascular healing. FIG. 1 emphasizes the uniform spacing of the scoring elements 104 around the balloon’s 102 circumference, which ensures even force distribution during plaque modification, while FIG. 4 provides a detailed view of the scoring element’s 104 cross-sectional profile, underscoring the catheter’s design to minimize trauma while enhancing efficacy in angioplasty procedures.
The manufacturing process of the scoring balloon catheter is depicted in FIG. 3, a flowchart outlining the sequential steps to fabricate the device. The process begins with the fabrication (step 300) of the elongate scoring element, which involves forming a core with a substantially D-shaped cross-sectional profile. The core, typically made from a biocompatible metal or reinforced polymer, is shaped using precision molding or extrusion techniques to achieve the desired flat bottom and substantially convex top surfaces. The core is then lined (step 302) with a polymer jacket, applied through coating or co-extrusion processes, to create a smooth, biocompatible outer layer that prevents vessel wall laceration. The process further involves welding (step 304) the scoring element to the outer surface of the polymer balloon. The balloon, pre-formed from a biocompatible polymer such as polyurethane, is positioned in a welding apparatus where one or more scoring elements are affixed using laser welding, ultrasonic welding, RF welding, or thermal fusion. The welding process is optimized to ensure a secure bond without compromising the balloon’s flexibility or inflation dynamics, with multiple welding technologies optionally combined to enhance attachment strength. The process further entails applying a therapeutic agent (step 306) to the balloon, scoring element, or both, using specialized deposition techniques such as spray coating or dip coating. The therapeutic agent, selected from Sirolimus, Paclitaxel, Everolimus, or a polymer-free antiproliferative drug, may be combined with a nanotechnology-based carrier to achieve controlled elution profiles. The process finally involves assembling the balloon onto the catheter shaft (step 308), integrating the balloon-scoring element assembly with the shaft’s lumens for guidewire and inflation fluid delivery. Quality control testing typically follows, verifying the catheter’s structural integrity, drug coating uniformity, and performance under simulated inflation conditions.

The scoring balloon catheter’s structural design is optimized to prevent arterial injury and balloon damage while ensuring flexibility and enhanced tracking through complex vascular pathways. The D-shaped scoring elements 104, with their convex top surfaces, apply focal force precisely to pathological tissue, creating controlled scores that facilitate plaque modification without deep cuts that could harm the vessel wall. The polymer jacket lining the scoring element core further reduces trauma by providing a smooth interface, while the robust welding attachment ensures durability during repeated inflation cycles. The catheter’s flexibility, derived from the biocompatible polymer balloon and streamlined shaft, allows it to navigate tortuous anatomy with ease, improving deliverability in challenging clinical scenarios. The therapeutic coating 110 (shown in fig. 5) enhances post-procedural outcomes by delivering antiproliferative agents directly to the treated site, reducing the risk of restenosis and promoting vascular healing.

Fig. 5 shows drug coating configuration on the outer surface of the scoring balloon catheter. This coating 110 is applied exclusively to the exposed areas of the balloon surface located between the scoring elements 104, maintaining drug-delivery function while preserving mechanical scoring performance. This selective coating strategy is critical for maintaining the scoring efficacy of the elements, as applying drug material directly over the wires could diminish their cutting or scoring precision. At the same time, this layout ensures maximum drug-transfer surface area on the balloon itself, enabling targeted delivery of therapeutic agents to the vascular wall during inflation.

In operation, the scoring balloon catheter is advanced over a guidewire through the vascular system to the site of pathological tissue development. Upon reaching the target, the balloon 102 is inflated, causing the scoring elements 104 to engage the vessel wall and pathological tissue. The convex top surfaces of the scoring elements 104 apply focal force, scoring the plaque to facilitate vessel dilation while minimizing trauma to the surrounding anatomical layers. The therapeutic agent 110, released from the balloon 102 or scoring element 104, penetrates the scored tissue, inhibiting neointimal hyperplasia and supporting long-term vessel patency. The balloon 102 is then deflated, and the catheter is withdrawn, leaving the treated vessel with improved blood flow and reduced risk of re-narrowing.

The scoring balloon catheter described herein represents a significant advancement in interventional cardiology, combining specialized scoring elements, robust attachment mechanisms, and advanced drug delivery to address the limitations of conventional devices. Its design ensures effective plaque modification, enhanced safety, and improved procedural outcomes, making it a valuable tool for treating vascular diseases.

It should be understood that the arrangements, conditions, and steps illustrated in the figures described herein are exemplary and that other variations and embodiments may be possible. It should also be understood that the various materials, components, concentrations, conditions, and method steps defined by the claims, described above, and illustrated in the various figures represent embodiments configured according to the subject matter disclosed herein. For example, one or more of the specific materials, conditions, or steps may be realized, in whole or in part, by variations described or encompassed by the figures and description.

Although the present disclosure and its advantages have been described in detail, it should be understood that various changes, substitutions, and alterations can be made herein without departing from the spirit and scope of the present disclosure as defined by the appended claims. , Claims:I/WE CLAIMS
1. A scoring balloon catheter 100 comprising:
(a) a catheter shaft for delivery within a blood vessel;
(b) a balloon 102 coupled to the catheter shaft and configured to expand within the blood vessel at a site where pathological tissue has built up;
(c) at least one elongate scoring element 104 disposed on the outer surface of the balloon 102, the scoring element 104 having a substantially convex, tissue-engaging top surface 108 configured to, upon the expansion of the balloon 102, dilate the interior vessel wall while applying contact-induced focal force to the pathological tissue resulting in the scoring of the pathological tissue while minimizing vessel trauma; and
(d) a secure attachment mechanism affixing the scoring element 104 to the balloon 102 surface to maintain attachment during the inflation and deflation cycles of the balloon 102.
2. The balloon catheter 100 as claimed in claim 1, wherein each of the at least one scoring element 104 is substantially semicylindrical in shape with the substantially planar side 106 thereof integrally abutting the outer surface of the balloon 102.
3. The balloon catheter 100 as claimed in claim 1, wherein cross-sectional shape of each of the at least one scoring element 104 is selected from the group consisting of: D-shaped, crescent, parabolic, tear-drop, semi-elliptical, asymmetrical ridge, and curved hybrid profiles.
4. The balloon catheter 100 as claimed in claim 1, wherein a therapeutic agent 110 is applied to the balloon 102 and/or the at least one scoring element 104.
5. The balloon catheter 100 as claimed in claim 4, wherein the therapeutic agent 110 is selected from the group consisting of Sirolimus, Paclitaxel, Everolimus, a polymer-free antiproliferative agent, or a combination thereof.
6. The balloon catheter 100 as claimed in claim 4, wherein the therapeutic agent 110 is delivered via a nanotechnology-based carrier configured to enable controlled drug elution.
7. The balloon catheter 100 as claimed in claim 1, wherein the at least one scoring element 104 is affixed to the balloon 102 using one or more welding techniques selected from the group consisting of laser welding, ultrasonic welding, radiofrequency RF welding, thermal bonding, or combinations thereof.
8. The balloon catheter 100 as claimed in claim 1, wherein the at least one scoring element 104 comprises a plurality of scoring elements 104, each of which disposed longitudinally along the balloon 102 surface.
9. The balloon catheter 100 as claimed in claim 1, wherein the scoring element 104 comprises a core lined with a polymer jacket, the polymer jacket configured to enhance biocompatibility and prevent vessel wall laceration.
10. A method of manufacturing a scoring balloon catheter 100, comprising:
(a) fabricating 300 an elongate scoring element 104 with a substantially D-shaped cross-sectional profile;
(b) welding 304 the scoring element 104 to a balloon 102 using one or more of laser welding, ultrasonic welding, or thermal fusion;
(c) applying 306 a therapeutic agent 110 to the balloon 102, scoring element 104, or both; and
(d) assembling 308 the balloon 102 onto a catheter shaft.