CN116212206A

CN116212206A - Balloon catheter assembly

Info

Publication number: CN116212206A
Application number: CN202310333753.3A
Authority: CN
Inventors: 王秀伟; 林琳; 刘继勇; 秦泗海; 李文松
Original assignee: Kossel Medtech Suzhou Co ltd
Current assignee: Kossel Medtech Suzhou Co ltd
Priority date: 2021-11-17
Filing date: 2021-11-17
Publication date: 2023-06-06
Also published as: CN113952597A; CN113952597B

Abstract

The embodiments of the specification disclose a balloon catheter assembly with a constraining structure, comprising a catheter hub, a balloon and a catheter connected between the catheter hub and the balloon; the balloon is wrapped with a constraint structure, the constraint structure comprises a connecting approaching end, a connecting far end and an action section connected between the connecting approaching end and the connecting far end, and the width of at least one connecting rod connected with the near end and/or the connecting far end is larger than that of at least one connecting rod of the action section.

Description

Balloon catheter assembly

Description of the division

The present application is a divisional application of chinese patent application CN 202111363690.3 entitled "balloon catheter assembly with constraining structure" filed on 11/17 of 2021.

Technical Field

The present disclosure relates to the field of medical devices, and more particularly to a balloon catheter assembly.

Background

The creation of percutaneous transluminal angioplasty is a significant advance in the treatment of vascular disease. Balloon angioplasty has been a well-established, relatively mature technique for many years. Balloon angioplasty is mainly aimed at the revascularization of stenosed and occluded vessels by inserting a catheter with an expanding balloon into the vascular system and then expanding the balloon in the stenosed and occluded region of the vessel under externally applied pressure, thereby applying radial pressure to the inner wall of the vessel to widen the stenosed and occluded region and further unblock the blood flow.

The expansion sacculus can be restrained by a restraining structure sleeved outside the expansion sacculus in the expansion process, so that the expansion sacculus has a certain expansion size and expansion shape. However, in practical applications, it is found that when the balloon is inflated, the constraint structure may be broken due to the problems of too low toughness or too concentrated stress, so as to damage the balloon and even cause serious injury to the patient. Therefore, it is necessary for those skilled in the art to study a more reliable balloon catheter assembly and constraining structure.

Disclosure of Invention

Embodiments of the present disclosure provide a balloon catheter assembly comprising a catheter hub, a balloon, and a catheter connected between the catheter hub and the balloon; the balloon is wrapped with a constraint structure, the constraint structure comprises a connecting approaching end, a connecting far end and an action section connected between the connecting approaching end and the connecting far end, and the width of at least one connecting rod connected with the near end and/or the connecting far end is larger than that of at least one connecting rod of the action section.

In some embodiments, the at least one connecting rod connecting the proximal end and/or the distal end has a width that is 2-4 times the width of the at least one connecting rod of the active segment.

In some embodiments, the catheter comprises an inner tube, an outer tube sleeved outside the inner tube, and a connecting tube disposed between the outer tube and the balloon; the distal end of the outer tube is connected with the connecting tube, and the outer surface of the connecting tube is connected with the proximal end of the balloon through an adhesive layer.

In some embodiments, the connecting tube is made of nylon or polyether block polyamide and the adhesive layer is made of polyether block amide.

In some embodiments, the length of the connecting tube is 8mm to 15mm.

In some embodiments, the adhesive layer is L-shaped in cross section.

In some embodiments, the constraining structure is a memory alloy stent integrally cut to form at least one rounded buffer segment at least one junction of wires in the memory alloy stent.

In some embodiments, the balloon is a single-layer balloon integrally made of nylon, nylon copolymer and/or polyethylene terephthalate plastic, or a double-layer balloon with an inner layer made of polyethylene terephthalate plastic and an outer layer made of nylon.

In some embodiments, the attached proximal end of the constraining structure is fixedly attached to the proximal end of the adhesive layer.

In some embodiments, each of the wires in the constraining structure is circular, trapezoidal, and/or triangular in cross-section.

Drawings

The present specification embodiments will be further described by way of exemplary embodiments, which will be described in detail with reference to the accompanying drawings. The embodiments are not limiting, in which like numerals represent like structures, wherein:

fig. 1 is a schematic structural view of a balloon catheter assembly according to some embodiments of the present description.

Fig. 2 is a schematic illustration of the connecting rods of the balloon catheter assembly of some embodiments of the present description.

Fig. 3 is an enlarged partial schematic view of a balloon catheter assembly according to some embodiments of the present disclosure.

Fig. 4 is a schematic illustration of the attachment of the adhesive layer of the balloon catheter assembly of some embodiments of the present disclosure.

Fig. 5 is a schematic view of wire connections of a constraining structure of a balloon catheter assembly of some embodiments of the present disclosure.

Fig. 6 is a schematic cross-sectional view of a wire of a constraining structure of a balloon catheter assembly of some embodiments of the present disclosure.

Detailed Description

In order to more clearly illustrate the technical solutions of the embodiments of the present specification, the drawings used in the description of the embodiments will be briefly described below. It is apparent that the drawings in the following description are only some examples or embodiments of the present specification, and it is possible for those of ordinary skill in the art to apply the present specification to other similar situations according to the drawings without inventive effort. It should be understood that these exemplary embodiments are presented merely to enable one skilled in the relevant art to better understand and practice the present description, and are not intended to limit the scope of the present description in any way. Unless otherwise apparent from the context of the language or otherwise specified, like reference numerals in the figures refer to like structures or operations.

As used in this specification and the claims, the terms "a," "an," "the," and/or "the" are not specific to a singular, but may include a plurality, unless the context clearly dictates otherwise. In general, the terms "comprises" and "comprising" merely indicate that the steps and elements are explicitly identified, and they do not constitute an exclusive list, as other steps or elements may be included in a method or apparatus. The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment".

In the description of the present specification, it should be understood that the terms "distal," "proximal," "inner," "outer," "distal," "proximal," "one end," and the like indicate orientations or positional relationships based on the orientation or positional relationships shown in the drawings, merely to facilitate description of the present specification and simplify the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be configured and operated in a particular orientation, and thus should not be construed as limiting the present specification.

In the present specification, unless clearly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and for example, "connected" may be either a fixed connection, a removable connection, or an integral body; can be directly connected or indirectly connected through an intermediate medium; may be a communication between two elements or may represent an interaction between two elements. Unless otherwise specifically defined, it will be understood by those of ordinary skill in the art that the specific meaning of the terms in this specification is to be understood as appropriate.

In the process of carrying out blood circulation reconstruction on a narrow and occluded blood vessel by using the sacculus forming operation, the sacculus catheter can be constrained by a constraint structure sleeved outside the sacculus catheter, so that the sacculus catheter has a certain expansion size and expansion shape, and the stress of the blood vessel is more accurate. However, in some practical applications, it is found that when the balloon is inflated, the constraint structure may be broken due to the problems of too low toughness or too concentrated stress, so as to damage the balloon, and even cause serious injury to the patient.

In view of the foregoing, some embodiments of the present disclosure provide a balloon catheter assembly that avoids the connecting rods at the proximal and/or distal ends of the constraining structure from having too low a toughness due to excessive wear during electropolishing by increasing the widths of the connecting rods at the proximal and/or distal ends of the constraining structure prior to electropolishing such that the width of at least one connecting rod at the proximal and/or distal ends is greater than the width of at least one connecting rod at the active segment of the constraining structure.

In other embodiments of the present description, the stress distribution of the constraining structure in the balloon catheter assembly may also be varied by changing its shape. For example, at least one rounded buffer section may be formed at the junction of the constraining structures to avoid breakage of the junction during expansion or contraction due to excessive stress concentration.

The balloon catheter assembly provided in the embodiments of the present specification is described in detail below with reference to the accompanying drawings.

Referring to fig. 1, in some embodiments, balloon catheter assembly 100 may include catheter hub 110, balloon 120, and catheter 130 connected between catheter hub 110 and balloon 120, wherein balloon 120 is wrapped with constraining structure 140 for limiting the balloon inflation size and inflation shape.

In some embodiments, balloon catheter assembly 100 may include one or more balloons 120, which one or more balloons 120 may be inflated or deflated under the control of an operator (e.g., a physician or nurse). When the balloon 120 is expanded, it can act on the inner wall of the blood vessel, thereby expanding the stenosed and occluded region in the blood vessel, and further widening the stenosed and occluded region in the blood vessel, so that the blood flow is more unblocked.

In some embodiments, when balloon catheter assembly 100 includes a plurality (e.g., two or more) of balloons 120, the plurality of balloons 120 may be arranged equidistantly or non-equidistantly in a sequence.

In some embodiments, the plurality of balloons 120 may be divided into a distal balloon and a proximal balloon according to their distance relationship from the catheter hub 110. Wherein the distal balloon may refer to one or more of the plurality of balloons that are distal to catheter hub 110, and similarly the proximal balloon may refer to one or more of the plurality of balloons that are proximal to catheter hub 110.

In some embodiments, balloon 120 may be made of one or more of nylon, nylon copolymer, or a polyethylene terephthalate (e.g., PET (Polyethylene terephthalate, polyester resin)).

Catheter hub 110 may be used to attach or secure catheter 130. In some embodiments, catheter 130 may include multiple internal lumens (e.g., guidewire lumen, distal balloon inflation lumen, proximal balloon inflation lumen, drug-carrying lumen, etc.), and catheter hub 110 may each have an interface disposed thereon that corresponds to each internal lumen of catheter 130.

For example, in some possible embodiments, catheter hub 110 may include a first port, a second port, a third port, and a fourth port thereon, the first port being connectable to a guidewire lumen of catheter 130 for guiding through the guidewire or detecting pressure within the lumen during surgery; the second port may be in communication with the distal balloon inflation lumen of the catheter 130, the third port may be in communication with the proximal balloon inflation lumen of the catheter 130, and the second port and the third port may be used to inject a liquid or gas into the distal balloon and the proximal balloon, respectively, during surgery, so as to control the sequential or simultaneous inflation of the respective balloons and to cause the inflation of the balloons at both ends to temporarily block blood flow, thereby forming a closed "vascular lumen"; the fourth port may be in communication with the drug-carrying lumen of catheter 130 for aspiration and infusion at the time of surgery through the fourth port using the obturator to dissolve the drug in the drug-carrying lumen from the blood in the closed vessel lumen and then return to the closed vessel lumen.

The above structures of catheter hub 110 and catheter 130 are only exemplary. In some other embodiments, catheter 130 may contain more or less internal cavities and, accordingly, catheter hub 110 may contain more or less ports thereon.

The constraining structure 140 may be wrapped around the outside of the balloon 120, thereby limiting its inflated size and inflated shape. Referring to fig. 2, in some embodiments, constraining structure 140 may include a connecting proximal end 141, a connecting distal end 142, and an active segment 143 connected between connecting proximal end 141 and connecting distal end 142 and acting on balloon 120 to limit its inflation size and inflation shape. Wherein the connecting proximal end 141 may refer to an end proximal to catheter hub 110 and the connecting distal end 142 may refer to an end distal to catheter hub 110.

In some embodiments, the active segment 143, the connecting proximal end 141, and/or the connecting distal end 142 of the constraint structure 140 may each comprise at least one connecting rod. The connecting rods connecting the proximal end 141 and/or the distal end 1 may be connected with other components of the balloon catheter assembly 100 to secure the constraining structure 140. The connecting rods of the action segments 143 may be interconnected and form a mesh-like annular structure that is capable of undergoing corresponding deformation as the balloon is inflated or deflated, wrapping the balloon 120, to limit the inflation size and inflation shape of the balloon 120.

In some embodiments, the biocompatibility of the constraint 140 is related to both the material-induced host reaction and the degradation of the material in the human environment. For example, in the case of a constraint structure made of a nickel-titanium alloy, dissolution of nickel ions causes problems such as allergy and inflammation, and the release rate of nickel ions is closely related to the surface quality of the constraint structure (the higher the corrosion resistance of the constraint structure is, the slower the release rate of nickel ions is, and the corrosion resistance of the constraint structure depends on the specific structure and surface morphology).

The surface morphology, in particular, the surface roughness, can be improved, i.e. reduced, by electrolytic polishing. However, when the constraint structure 140 is processed by electropolishing, since the number of connecting rods of the active segment 143 is greater than the number of connecting rods of the connecting proximal end 141 and/or the connecting distal end 142, the connecting rods at the connecting proximal end 141 and/or the connecting distal end 142 pass a greater current than the connecting rods at the active segment 143, which results in an excessive loss of width of the connecting rods at the connecting proximal end 141 and/or the connecting distal end 142 after polishing, which in turn results in a certain safety risk for the constraint structure 140.

Thus, to avoid excessive loss of width after polishing of the connecting rods at the proximal and/or

distal ends

141, 142, in some embodiments, compensation for the lost rod width during electrochemical polishing may be achieved by increasing the width of the connecting rods at the proximal and/or

distal ends

141, 142 prior to electrochemical polishing.

Based thereon, in some embodiments, the width of at least one connecting rod at the proximal and/or distal connecting ends 141, 142 may be greater than the width of at least one connecting rod at the active segment 143, thereby ensuring that the connecting rod at the proximal and/or distal connecting ends 141, 142 and the connecting rod at the active segment 143 have widths that meet predetermined requirements after electropolishing. It should be noted that, the "width" of the connecting rod described in the present specification may refer to a dimension perpendicular to the length extending direction of the connecting rod.

Referring to fig. 2, in some embodiments, the connecting rod 1411 at the proximal end 141 and the connecting rod 1421 at the distal end 142 may be in a substantially parallel state, and the connecting rod 1431 at the active section 143 may be connected to a plurality of wires of S-shaped structure to form a mesh structure wrapped around the balloon 120. Wherein the connecting rod 1411 at the connecting proximal end 141 and the connecting rod 1421 at the connecting distal end 142 are "substantially parallel" may refer to an angle therebetween of less than or equal to 15 °.

Referring to fig. 2, in some embodiments, the number of connecting rods 1431 located at the active section 143 may be twice the number of connecting rods 1411 located at the connecting proximal end 141 or connecting rods 1421 located at the connecting distal end 142, in other words, the current flowing through the connecting

rods

1411 and 1421 may be twice the current flowing through the connecting rods 1431.

Based on this, in some embodiments, to ensure that the connecting rods 1411 and/or 1421 at the connecting proximal end 141 and/or the connecting distal end 142 and the connecting rods 1431 at the active section 143 have widths that meet predetermined requirements after electropolishing, the widths of the connecting rods 1411 and/or 1421 at the connecting proximal end 141 and/or the connecting distal end 142 before electropolishing may be set to 1.5 to 4 times the widths of the connecting rods 1431 at the active section 143.

Alternatively, in some embodiments, the width of the connecting rods 1411 and/or 1421 can also be 2-4 times the width of the connecting rod 1431; in some embodiments, the width of the connecting rods 1411 and/or 1421 may also be 1.5 times to 3.5 times the width of the connecting rod 1431; in some embodiments, the width of the connecting rods 1411 and/or 1421 may also be 1.5-3 times the width of the connecting rod 1431; in some embodiments, the width of the connecting rods 1411 and/or 1421 may also be 2-3 times the width of the connecting rod 1431.

In some embodiments, the width W1 of the connecting rods 1411 and/or 1421, prior to electropolishing, at the connecting proximal end 141 and/or connecting distal end 142 may be between 0.2mm and 0.3mm, and the width W2 of the connecting rod 1431, prior to electropolishing, at the working section 143 may be between 0.08mm and 0.15 mm.

It should be noted that the above quantitative relationship between the connecting rod 1431 and the connecting rods 1411 and/or 1421 is only exemplary. In some embodiments, the ratio of the number of connecting rods 1431 to the number of connecting

rods

1411 or 1421 can be less than or greater than 2, and accordingly, the ratio of the width of the connecting rods 1411 and/or 1421 to the width of the connecting rods 1431 can be less than 2 or greater than 4.

Fig. 3 is a schematic structural view of a balloon catheter assembly according to further embodiments of the present disclosure.

As shown in fig. 3, in some embodiments, the catheter 130 may include a stress diffuser 131, an inner tube 132, an outer tube 133 that fits over the inner tube 132, and a connecting tube 134 disposed between the outer tube and the balloon proximal end 1201. Wherein, one end of the stress diffusion tube 131 is connected with the catheter holder 110, and the other end is connected with the proximal end of the outer tube 133. The distal end of outer tube 133 is coupled to the proximal end of connecting tube 134, and the distal end of connecting tube 134 is coupled to proximal end 1201 of balloon 120 by adhesive layer 135.

In some embodiments, the inner tube 132 may be a tubular element, such as a round tube, square tube, or other regular/irregular shaped element. In some embodiments, the inner tube 132 may include a plurality of inner lumens, such as a guidewire lumen, a distal balloon inflation lumen, a proximal balloon inflation lumen, a drug-carrying lumen, for housing a guidewire, a distal inflation gas or liquid, a proximal inflation gas or liquid, an active drug, and the like, respectively.

In some embodiments, the inner tube 132 may be fabricated from a metal or polymeric material, such as stainless steel, polyamide, polyether block amide, polyurethane, or the like. In some embodiments, the inner and/or outer walls of the inner tube 132 may include a lubricious coating, such as a polytetrafluoroethylene coating, or the like, to reduce the frictional resistance thereof.

In some embodiments, the outer tube 133 may be braided from wire. Also, to provide better directionality of the outer tube 133 as it enters the vascular system, in some embodiments, the wire used may be a flat wire (i.e., a wire that is flat).

In some embodiments, to reduce the size of the outer tube 133, the wire may be stainless steel wire or nickel titanium wire, preferably flat stainless steel or nickel titanium wire having a thickness of less than 0.2mm, such as 0.1mm, 0.08mm, 0.15mm, etc., is braided so that the inner diameter of the entire outer tube 133 is controlled to be 0.6mm to 1.2mm and the outer diameter is correspondingly controlled to be 0.8mm to 1.4mm.

In some embodiments, the outer tube 133 may include an outer layer and an inner layer, and the outer layer and/or the inner layer may be polyimide, polyether block amide, polytetrafluoroethylene, or the like. In some embodiments, to control the thickness of the outer and/or inner layers to be less than 0.2mm, the wire may be wound directly onto the inner layer of the outer tube 133 or the wire may be co-extruded with the outer and/or inner layers.

In some embodiments, the outer tube 133 may be bonded to the stress-diffusing tube 131 by an adhesive, for example, the stress-diffusing tube 131 may be positioned with the outer tube 133, and then the adhesive may be added, which may be applied to sufficiently bond the two by capillary action through a small space therebetween. Exemplary adhesives may include polyimide adhesives, polytetrafluoroethylene adhesives, and the like.

In some embodiments, to enhance pushability and twistability of balloon 120, the connection of the distal end of outer tube 133 to the proximal end of balloon 120 may be connected by connecting tube 134 and adhesive layer 135.

In some embodiments, the distal end of outer tube 133 may be coupled to the proximal end of connecting tube 134, and the distal end of connecting tube 134 may be coupled to proximal end 1201 of balloon 120 by adhesive layer 135. In some embodiments, to reduce the outer diameter size of catheter 130 as much as possible, adhesive layer 135 may be attached to the outer surface of connecting tube 134 and/or the inner surface of proximal end 1201 of balloon 120.

In some embodiments, to achieve adequate bonding, bonding layer 135 may bond simultaneously with the inner surface of proximal end 1201 of balloon 120, the outer surface of the distal end of connecting tube 134, and the cross-section of the distal end of connecting tube 134.

In some embodiments, the outer tube 133 and balloon 120 may have a difference in radial dimensions, and the connecting tube 134 may be of a variable diameter configuration to ensure that the ends of the connecting tube 134 may be reliably connected to the proximal end 1201 of the balloon 120 and the distal end of the outer tube 133, respectively. Specifically, the dimensions of the two ends of the connecting tube 134 may be different, wherein the dimension of the end near the outer tube 133 may be the same as or close to the dimension of the outer tube 133, and the dimension of the end near the balloon proximal end 1201 may be the same as or close to the dimension of the balloon proximal end 1201.

In some embodiments, to provide better torqueability of the balloon segment, a softer connecting tube 134 may be used to connect the outer tube 133 and the proximal end 1201 of the balloon 120. In some embodiments, the connecting tube 134 and the adhesive layer 135 may be made of different soft materials.

In some embodiments, to facilitate bonding, the bonding layer 135 may be a lower melting point material. In some embodiments, the melting point of the material used for the adhesive layer 135 may be lower than the melting point of the material used for the connection pipe 134.

In some embodiments, the connection tube 134 may be made of nylon or polyether block Polyamide (PEBAX) material, and the adhesive layer 135 may be made of polyether block amide (PEBA) material.

In some embodiments, the soft material may increase the torsion performance, but may also cause the pushing performance to be poor, so by providing the adhesive layer 135 at the connecting tube 134, on one hand, the connecting tube 134 made of the soft material may be slightly thickened to enhance the toughness, and on the other hand, the material adopted by the adhesive layer 135 has a lower melting point, and may also be quickly melted when heated, so as to firmly connect the distal end of the outer tube 133 and the proximal end 1201 of the balloon.

Fig. 4 is a schematic view of an adhesive layer of a balloon catheter assembly according to some embodiments of the present disclosure.

Referring to fig. 4, in some embodiments, in order to achieve sufficient adhesion of adhesive layer 135 to connecting tube 134 and proximal end 1201 of the balloon, adhesive layer 135 may be provided in an L-shaped configuration in cross-section. Specifically, the adhesive layer 135 may include a first connection portion 135-1 and a second connection portion 135-2, wherein the first connection portion 135-1 has a thickness greater than that of the second connection portion 135-2, the first connection portion 135-1 may be simultaneously connected with a section of the distal end of the connection tube 134 and an inner surface of the proximal end 1201 of the balloon, and the second connection portion 135-2 may be connected with an outer surface of the connection tube 134. It should be noted that, by connecting the abutment tube 134 and the proximal end 1201 of the balloon by the adhesive layer 135 having an L-shaped cross section, the connection area between the abutment tube 134 and the balloon can be increased, and the connection relationship between the abutment tube and the balloon can be more reliable.

In some embodiments, adhesive layer 135 may be thermally welded using a laser, heat radiating metal jaws, RF energy, or other methods. In some embodiments, the thermal welding temperature may be controlled in several ramp-up stages: in the first stage, the welding temperature is raised to 100-110 ℃ for 20-30 s, so that the bonding layer 135 is softened; in the second stage, the welding temperature is raised to 150-160 ℃ for 80-100 s, and the bonding layer 135 is sufficiently welded.

In some embodiments, it has been found experimentally that when the length of the connecting tube 134 is too long (e.g., greater than 15 mm), the pushing force is not transmitted, resulting in poor pushing performance, and when the length of the connecting tube 134 is too short (e.g., less than 8 mm), the twisting performance is poor due to the plurality of welding points being too close together.

Based on the above test results, in some embodiments, to ensure a combination of torsional and pushing properties of the balloon segment, the length of the connecting tube 134 may be controlled between 8mm and 15mm. Alternatively, in some embodiments, the length of the connecting tube 134 may be 8mm to 10mm; in some embodiments, the length of the connecting tube 134 may be 10mm to 15mm; in some embodiments, the length of the connecting tube 134 may be 9mm to 12mm.

In some embodiments, it is contemplated that the torsional and pushing properties of the balloon segment are also related to the thickness of the connecting tube 134, whether the adhesive layer 135 is added, and the thickness of the adhesive layer 135. To ensure a combination of torsional and pushing properties of the balloon segment, in some embodiments, an adhesive layer 135 may be provided at the junction of the connecting tube 134 and the proximal end 1201 of the balloon, with the thickness of the adhesive layer 135 being controlled between 0.1mm and 0.2mm, and the thickness of the connecting tube 134 being controlled between 0.1mm and 0.2mm.

In order to verify the feasibility of the above with respect to the thickness of the adhesive layer 135 and the thickness of the connection tube 134, the applicant conducted a corresponding test. Exemplary test results are shown in the following table:

as can be seen from the above table, when the adhesive layer 135 is provided at the junction of the connection tube 134 and the proximal end 1201 of the balloon, and the thickness of the adhesive layer 135 is controlled to be between 0.1mm and 0.2mm, and the thickness of the connection tube 134 is controlled to be between 0.1mm and 0.2mm, the balloon catheter assembly 100 has a larger maximum pushing force and a better overbending capability (i.e., has better torsion performance and pushing performance). Illustratively, in some embodiments, the thickness of the connection tube 134 may be set to 0.1mm, and the thickness of the adhesive layer 135 may be set to 0.2mm; in some embodiments, the thickness of the connection pipe 134 may be set to 0.2mm and the thickness of the adhesive layer 135 may be set to 0.1mm.

In some embodiments, balloon 120 may be 20mm to 40mm in length and 5mm to 16mm in diameter to accommodate peripheral requirements. Alternatively, in some embodiments, balloon 120 may be 20mm to 30mm in length and 5mm to 10mm in diameter; in some embodiments, balloon 120 may be 25mm to 35mm in length and 8mm to 12mm in diameter.

In some embodiments, balloon 120 may be a single-layer balloon made of nylon or nylon copolymer, or a polyethylene terephthalate plastic, or a double-layer balloon with an inner layer made of a polyethylene terephthalate plastic and an outer layer made of nylon. In some embodiments, the balloon 120 is configured as a double-layer balloon with an inner layer made of a polyethylene terephthalate plastic and an outer layer made of nylon, so that the constraint structure 140 can prevent the balloon 120 from being damaged due to excessive force applied to the balloon when the balloon is inflated.

In some embodiments, the constraining structure 140 may be a memory alloy stent formed by integral cutting (e.g., laser integral cutting), and exemplary memory alloys may include nickel-titanium alloys, copper-nickel alloys, and the like. Referring to fig. 2 and 5, in some embodiments, the memory metal stent may comprise several wires that may be divided into a connecting rod 1411 at the connecting proximal end 141, a connecting rod 1421 at the connecting distal end 142, a connecting rod 1431 at the active section 143, and an S-shaped structure that is crisscrossed with the connecting rod 1411 at the connecting proximal end/the connecting rod 1421 at the connecting distal end/the connecting rod 1431 at the active section, depending on the location or shape.

In some embodiments, the plurality of S-shaped structures may be arranged in an array along the direction of arrangement of the balloon 120. Wherein each column forms a wave-shaped confinement ring, each confinement ring being connectable to at least one of the connecting rod 1411 at the proximal end of the link, the connecting rod 1421 at the distal end of the link, and the connecting rod 1431 at the active section. In some embodiments, to have the constraining structure 140 have approximately the same constraining force on the balloon 120 at different locations, multiple constraining rings may be equally spaced apart.

The S-shaped structure may form a confinement ring that expands or contracts with the balloon 120 to limit the size and shape of the balloon 120, in other words, the S-shaped structure may form a confinement ring that matches longitudinal and radial expansion of the balloon 120 during inflation and may maintain the balloon 120 in a desired position during inflation.

In some embodiments, the total length that the constraining ring formed by the S-shaped structure achieves upon inflation of balloon 120 may be greater than the maximum circumference of balloon 120 upon inflation. In some embodiments, to make the constraining effect of the constraining rings on balloon 120 about the same, different constraining rings may be provided having about the same constricting performance and circumference.

In some embodiments, at least one rounded buffer segment may be formed at least one connection intersection 1432 of each wire in the memory metal stent. Specifically, the connection intersection point of any two metal wires in the memory metal bracket forms a round angle or a circular arc structure during cutting, so that the bracket is prevented from being broken in the expansion or contraction process due to the fact that stress is too concentrated at the connection intersection point 1432 of each metal wire, and serious injury is further caused to a patient. In addition, by providing the connection intersection 1432 with a rounded or circular arc structure, the balloon 120 can be prevented from being damaged due to too sharp force against the balloon 120, as compared to a sharp-angled structure such as an acute angle or a right angle.

Referring to fig. 5, in some embodiments, the rounded or rounded structure formed by the connection points of the wires when cut may be a circular arc of radius R1, which may be concave or convex with respect to the connection points. In some embodiments, the radius R1 corresponding to the rounded or circular arc structure may be between 0.5mm and 1mm, where the radius R1 corresponding to the rounded or circular arc structure at each connection intersection point and the arc length may be the same or different.

In some embodiments, the connecting proximal end 141 of the constraining structure 140 may be connected at the proximal end of the adhesive layer 135 (e.g., the second connecting portion 135-2) or the proximal end 1201 of the balloon. In some embodiments, by attaching the attachment proximal end 141 of the constraining structure 140 at the proximal end of the adhesive layer 135 (e.g., the second attachment portion 135-2), the attachment proximal end 141 of the constraining structure 140 can be prevented from expanding with the balloon, thereby achieving a better constraining effect, and the overall outer diameter dimension of the catheter 130 can also be reduced to some extent, as compared to the attachment at the proximal end 1201 of the balloon.

The connecting distal end 142 of the constraining structure 140 may be connected to the distal end of the balloon 120, wherein the distal end of the balloon 120 may refer to the position of the balloon 120 furthest from the catheter hub 110. In some embodiments, the connecting distal end 142 of the constraining structure 140 may be fixedly connected to the distal end of the balloon 120 by means of an adhesive or snap fit, and similarly, the connecting proximal end 141 of the constraining structure 140 may also be fixedly connected to the proximal end of the adhesive layer 135 or the proximal end 1201 of the balloon by means of an adhesive or snap fit.

Referring to fig. 6, in some embodiments, the cross-section of the wire in the constraining structure 140 may be one or more of trapezoidal (as shown in fig. 6A), triangular (as shown in fig. 6B), or circular (as shown in fig. 6C), which may refer to a cross-section perpendicular to the length extension of the wire. In some embodiments, the radial dimension of the wires in the constraining structure 140 may be 0.1mm to 0.2mm. It should be noted that the above shapes of the cross sections of the wires are only exemplary, and in the present embodiment, the cross sections of the wires may be, but are not limited to, trapezoidal, triangular, and circular. For example, in some embodiments, the cross-sectional shape of the wire may also be rectangular.

In some embodiments, the outer surface of balloon 120 and the outer surface of constraining structure 140 may be used to apply a drug. In some embodiments, the drug may be applied to the outer surface of balloon 120 and/or the outer surface of constraining structure 140 in a single application. In other embodiments, an opening communicating with the drug-carrying lumen inside the catheter 130 may be provided between two adjacent balloons 120, and the drug may be delivered through the drug-carrying lumen provided in the catheter 130, and delivered to the outer surface of the balloon 120 and/or the outer surface of the constraining structure 140 via the opening provided between two adjacent balloons, or dissolved directly in the lumen of the blood vessel, where the outer surface of the constraining structure 140 may refer to the side thereof facing away from the balloon 120. In some embodiments, the balloon catheter assembly 100 may further include a developing assembly, and the drug may be precisely delivered to the target location to be treated at a fixed point according to the intravascular image obtained by the developing assembly, so as to improve the therapeutic effect of the drug on the inner wall of the blood vessel to a certain extent.

In some embodiments, to increase the area of drug applied to the outer surface of the containment structure 140, the containment structure 140 may be constructed from a wire having a trapezoidal cross-section, with the lower bottom surface 610 of the wire having a trapezoidal cross-section facing outwardly (i.e., away from the balloon 120), or from a wire having a triangular cross-section, with the longest one of the three sides (e.g., 621) facing outwardly (i.e., away from the balloon 120). Considering that the force applied to the balloon 120 from the side of the wire facing the balloon 120 may be relatively sharp (i.e., the force applied to the balloon per unit area is relatively large) when the cross-sectional shape of the wire is triangular, in order to avoid damage to the balloon due to the excessive sharpness of the force applied to the wire during inflation, in some embodiments, the area of the side of the wire facing the balloon 120 and in contact with the balloon 120 may be increased, for example, the angle of one corner of the triangle facing the balloon 120 may be increased to an obtuse angle greater than 120 °, thereby increasing the contact area of the wire with the balloon 120 during inflation of the balloon and reducing the force applied to the balloon per unit area and increasing the area of the side 620 facing away from the balloon 120, thereby increasing the area available for drug application. In some embodiments, the exterior surface of the constraining structure may be provided with a drug coating. In some embodiments, the drug coating may be disposed only on the outer surface of the balloon and not on the outer surface of the constraining structure, because the balloon, if disposed on the outer surface of the constraining structure, may cause the wire portion of the constraining structure to form a depression relative to the balloon during the inflation process, and may not contact the inner wall of the blood vessel, thereby disabling drug release.

In some embodiments, the drug coating on the outer surface of the constraint structure 140 may comprise at least one other active drug in addition to the macrolide drug, for example at least one selected from paclitaxel and derivatives thereof, rapamycin and derivatives thereof, phosphodiesterase inhibitors, thrombin inhibitors, thymidine kinase inhibitors, antibiotics, adenosine. It should be noted that the above drugs are merely exemplary, and in the present embodiment, the drug coating on the outer surface of the constraint structure 140 may be, but is not limited to, the aforementioned exemplary drugs.

While the basic concepts have been described above, it will be apparent to those skilled in the art that the foregoing detailed disclosure is by way of example only and is not intended to be limiting. Although not explicitly described herein, various modifications, improvements, and adaptations to the present disclosure may occur to one skilled in the art. Such modifications, improvements, and modifications are intended to be suggested within this specification, and therefore, such modifications, improvements, and modifications are intended to be included within the spirit and scope of the exemplary embodiments of the present invention.

Meanwhile, the specification uses specific words to describe the embodiments of the specification. Reference to "one embodiment," "an embodiment," and/or "some embodiments" means that a particular feature, structure, or characteristic is associated with at least one embodiment of the present description. Thus, it should be emphasized and should be appreciated that two or more references to "an embodiment" or "one embodiment" or "an alternative embodiment" in various positions in this specification are not necessarily referring to the same embodiment. Furthermore, certain features, structures, or characteristics of one or more embodiments of the present description may be combined as suitable.

Likewise, it should be noted that in order to simplify the presentation disclosed in this specification and thereby aid in understanding one or more inventive embodiments, various features are sometimes grouped together in a single embodiment, figure, or description thereof. This method of disclosure, however, is not intended to imply that more features than are presented in the claims are required for the present description. Indeed, less than all of the features of a single embodiment disclosed above.

In some embodiments, numbers describing the components, number of attributes are used, it being understood that such numbers being used in the description of embodiments are modified in some examples by the modifier "about," approximately, "or" substantially. Unless otherwise indicated, "about," "approximately," or "substantially" indicate that the number allows for a 20% variation. Accordingly, in some embodiments, numerical parameters set forth in the specification and claims are approximations that may vary depending upon the desired properties sought to be obtained by the individual embodiments. In some embodiments, the numerical parameters should take into account the specified significant digits and employ a method for preserving the general number of digits. Although the numerical ranges and parameters set forth herein are approximations that may be employed in some embodiments to confirm the breadth of the range, in particular embodiments, the setting of such numerical values is as precise as possible.

Each patent, patent application publication, and other material, such as articles, books, specifications, publications, documents, etc., referred to in this specification is incorporated herein by reference in its entirety. Except for application history documents that are inconsistent or conflicting with the content of this specification, documents that are currently or later attached to this specification in which the broadest scope of the claims to this specification is limited are also. It is noted that, if the description, definition, and/or use of a term in an attached material in this specification does not conform to or conflict with what is described in this specification, the description, definition, and/or use of the term in this specification controls.

Finally, it should be understood that the embodiments described in this specification are merely illustrative of the principles of the embodiments of this specification. Other variations are possible within the scope of this description. Thus, by way of example, and not limitation, alternative configurations of embodiments of the present specification may be considered as consistent with the teachings of the present specification. Accordingly, the embodiments of the present specification are not limited to only the embodiments explicitly described and depicted in the present specification.

Claims

1. A constraining structure of a balloon catheter assembly, comprising a proximal end, a distal end, and an active segment connected between the proximal end and the distal end; the number of the connecting rods of the acting section is larger than that of the connecting rods connected with the proximal end and/or the connecting rods connected with the distal end; processing the constraint structure by electrolytic polishing; the width of the connecting rod at the connecting near end and/or the connecting far end is 1.5-4 times of the width of the connecting rod at the acting section.

2. The constraining structure of claim 1, wherein the constraining structure is wrapped around the balloon and is a memory alloy stent formed by integral cutting.

3. A constraint according to claim 1, wherein the at least one connecting rod connecting the proximal and/or distal ends has a width of 2-4 times the width of the at least one connecting rod of the active segment.

4. The constraining structure of claim 1, wherein an outer surface of the constraining structure is provided with a drug coating.

5. The constraining structure of claim 1, wherein an outer surface of the balloon is provided with a drug coating.

6. The constraining structure of claim 1, wherein the constraining structure is a memory alloy stent formed by integral cutting, at least one rounded buffer segment being formed at least one junction of each wire in the memory alloy stent.

7. The constraining structure of claim 1, wherein the balloon is a single layer balloon of nylon, nylon copolymer and/or polyethylene terephthalate plastic as a whole, or a double layer balloon of polyethylene terephthalate plastic as an inner layer and nylon as an outer layer.

8. The constraining structure of claim 1, wherein the connecting proximal end of the constraining structure is fixedly attached to the proximal end of the adhesive layer.

9. A constraining structure as in claim 1, wherein each wire in the constraining structure is circular, trapezoidal and/or triangular in cross-section.

10. A balloon catheter assembly comprising the constraining structure of claim 1.