CN117899337A

CN117899337A - Balloon catheter

Info

Publication number: CN117899337A
Application number: CN202211244513.8A
Authority: CN
Inventors: 续文恒; 季方秋; 古湖南; 陈丽君; 王成; 潘远航
Original assignee: Shanghai Bomai'an Medical Technology Co ltd
Current assignee: Shanghai Bomai'an Medical Technology Co ltd
Priority date: 2022-10-12
Filing date: 2022-10-12
Publication date: 2024-04-19

Abstract

The present invention provides a balloon catheter comprising: a balloon comprising a balloon body portion, the balloon having a compressed state and an expanded state; and a balloon constraining assembly comprising at least one constraining rod helically wound around at least a portion of an outer surface of the balloon body to form a helical structure extending in an axial direction of the balloon; at least a portion of the restraining bar is configured to radially restrain at least a portion of the balloon body portion when the balloon is in an expanded state. According to the invention, the constraint rod forms the spiral structure outside the main body part of the balloon, so that the balloon has better holding back property compared with other constraint structures, and meanwhile, the spiral structure extends and winds along the axial direction of the balloon, so that constraint forces in different directions can be applied to the balloon, and the axial expansion of the balloon is more sufficient.

Description

Balloon catheter

Technical Field

The invention relates to the technical field of medical instruments, in particular to a balloon catheter.

Background

With the improvement of human living standard, the incidence of vascular diseases has been rising year by year and there is a trend of younger. Atherosclerosis caused by fat metabolism disorder, neurovascular dysfunction and other factors is a common vascular disease, and the main clinical symptoms of the atherosclerosis are dizziness, headache, chest distress, chest pain, abdominal pain, refractory hypertension, lower limb gangrene and the like, which greatly influence the life quality of patients and even possibly threaten life. Percutaneous Transluminal Angioplasty (PTA) has the advantages of small trauma, short recovery time and the like, and is gradually becoming a common method for treating atherosclerosis and reconstructing blood circulation paths.

The PTA implementation method is that a cylindrical balloon catheter with the diameter similar to that of a lesion blood vessel and the length similar to that of the lesion part is selected, the balloon part is placed at a narrow part, and then the balloon part is inflated by pressurizing, so that the purpose of expanding the blood vessel is finally achieved. In the past clinical treatment, the blood vessels after the expansion of the conventional balloon catheter are often accompanied by problems such as dissection, acute occlusion of the blood vessels, restenosis and the like, and particularly, the probability of occurrence of dissection and the need for implantation of a remedial stent is greatly increased when balloon component expansion is performed in calcified lesions (high-resistance lesion areas).

In the use of conventional balloon members for vasodilation, a certain pressure is required to achieve vessel patency, and the process of expanding the balloon member by pressure is often rapid, forceful, unbalanced, and may cause uncontrolled damage to the vessel wall. In general, the conventional balloon member generally only plays a role of pre-expansion, and a stent is required to be implanted in order to prevent elastic retraction of a blood vessel, but the damaged blood vessel is required to be endothelialized, and excessive endothelialization causes problems such as thrombus in the stent and restenosis in the stent in each stage. Later, drug stents have been developed to prevent the vessel from overgrowing during endothelialization, but to prevent the arterial dissection caused by the vessel injury from being absolutely overcome, thereby affecting the patency of the near and far phases. Thus, reducing vascular damage is a critical challenge to be overcome in the treatment of vascular disease.

Balloon component angioplasty results in vascular injury when treating vascular disease, mainly for two reasons: first, balloon members are unevenly inflated. Because of the eccentric stenosis or differential calcification of the plaque, the balloon member is not balanced in resistance when expanded, in which case the flexible or semi-flexible balloon member will over-expand at the less resistant sites and be constrained at the more resistant sites, creating a "dog bone" like expanded morphology, which uneven expansion can cause vascular trauma. Second, large shear forces are generated when the balloon member is deployed. In order to smoothly extend a balloon member having an approximate diameter to a blood vessel into a stenosed vascular lesion, it is necessary to fold and wind the balloon member so as to reduce the size of the balloon member. When the balloon member is inflated, the deployment and inflation of the balloon member is powerful, and shear forces generated during deployment are applied to the vessel wall causing damage thereto.

In order to solve the problem of damage to the blood vessel by the balloon member, attempts have been made to improve the structure of the balloon member. As patent application CN112402771a proposes a concave-convex balloon member that can achieve uniformity of expansion. The implementation method of the concavo-convex balloon component is to mold in a concavo-convex mold or to engrave or chemically erode the surface of the cylindrical balloon component, and when the balloon component expands, the convex structure of the outer surface concentrates the pressure in the balloon component, thereby achieving the effect of high-pressure expansion and having even stress. However, the molding process of such an uneven balloon member is very complicated, and particularly, a carving or chemical ablation method inevitably causes damage to the balloon member to some extent, increasing the risk of the balloon member being broken. In addition, as proposed in patent application CN107550610a, a balloon catheter covered with a metal mesh is generally cylindrical, and the cylindrical metal mesh limits over-expansion of the balloon member, so that a uniform expansion effect can be achieved. However, the existing products have certain defects, for example, a cylindrical metal net only plays a role in binding the effective length part of the balloon component, and the effective binding area is limited; in addition, the requirement for further improving the distensibility of the balloon component to the site of the vascular stenosis is not met.

Disclosure of Invention

In view of the problems in the prior art, it is an object of the present invention to provide a balloon catheter that improves the ability of balloon components to dilate a stenotic lesion and reduces damage to the vessel wall.

The embodiment of the invention provides a balloon catheter, which comprises:

a balloon comprising a balloon body portion, the balloon having a compressed state and an expanded state; and

The balloon restraint assembly comprises at least one restraint rod, wherein the restraint rod is spirally wound on at least part of the outer surface of the balloon main body part to form a spiral structure, and the spiral structure extends along the axial direction of the balloon;

At least a portion of the restraining bar is configured to radially restrain at least a portion of the balloon body portion when the balloon is in an expanded state.

In some embodiments, the balloon restraint assembly further comprises a plurality of restraint rings spaced apart along the axial direction of the balloon and connected to the restraint rod;

At least a portion of the restraining bar and the plurality of restraining rings form a first tubular mesh structure configured to radially restrain at least a portion of the balloon body portion when the balloon is in an expanded state.

In some embodiments, the balloon further comprises two tube legs respectively communicating with the two axial ends of the balloon body portion and two tapers respectively connecting the two tube legs with the balloon body portion.

In some embodiments, the number of the restraining rods is at least two, and the at least two restraining rods are spirally wound on the outer surfaces of the balloon main body part, the tube leg part and the cone part in parallel, and the restraining rods form a second tubular grid structure on the outer surface of the tube leg part.

In some embodiments, the balloon restraint assembly is made of wire, the wire outside the balloon body portion and the taper has a trapezoidal cross section, a first base of the trapezoid is farther from the surface of the balloon body portion and the taper than a second base, and a length of the first base is less than a length of the second base.

In some embodiments, in a cross section of the wire outside the taper in a direction from the balloon body portion to the tube leg portion, a length of the first base gradually increases to a length of the second base.

In some embodiments, the balloon restraint assembly is made of a shape memory metal.

In some embodiments, the outer surface of the cone includes at least one region coated with a layer of glue.

In some embodiments, the glue layer is evenly distributed along the circumference of the taper.

In some embodiments, the material of the glue layer is a biocompatible material, and the thickness of the glue layer is 0.001mm-0.1mm.

In some embodiments, when the balloon is in the expanded state, a concave low region is formed at a position where the balloon restraint assembly is arranged on the outer surface of the balloon main body part, a convex high region is formed at a position where the balloon restraint assembly is not arranged, and a vertical height difference between the high region and the low region is 0.01mm-1mm.

In some embodiments, further comprising an inner tube extending through the balloon, a distal end of the inner tube being connected to a distal end of the balloon; and

An outer tube, the proximal end of the balloon being connected to the distal end of the outer tube.

The balloon catheter provided by the invention has the following advantages:

The spiral structure is formed on the outer side of the balloon through the constraint rod, compared with other constraint structures, the balloon has better recoil, and meanwhile, the spiral structure extends and winds along the axial direction of the balloon, so that the balloon expansion can be limited radially.

In some embodiments, the restraining bar and the limit ring of the present invention combine to form a first tubular mesh structure, which may further achieve radial restraint of the balloon body portion, thereby allowing for more uniform balloon expansion.

In some embodiments, the outer sides of the two ends of the balloon are provided with the second tubular grid structures formed by the constraint rods, the outer sides of the two cones are provided with the spiral structures formed by the constraint rods, and the spiral structures on the outer sides of the cones can perform untwisting movement along with the expansion of the balloon, so that the bending of the balloon caused by the overlarge constraint force of the balloon constraint component on the balloon is avoided, and the reclassifying performance of the balloon is facilitated during pressure relief.

In some embodiments, the balloon cone of the present invention has areas coated with biocompatible glue, the coated areas being hard in texture, such that the cone expansion capacity is reduced, and balloon cone over-inflation can be effectively prevented.

Drawings

Other features, objects and advantages of the present invention will become more apparent upon reading of the detailed description of non-limiting embodiments, made with reference to the following drawings.

FIG. 1 is a schematic view of a balloon catheter according to an embodiment of the present invention;

FIG. 2 is a schematic structural view of a balloon restraint assembly in a contracted state according to one embodiment of the present invention;

FIG. 3 is a schematic view of the structure of a balloon according to an embodiment of the present invention;

Fig. 4 is a left side view of the balloon of fig. 3.

Reference numerals:

100. balloon catheter 118 taper

110. Balloon 119 tube leg

111. Low area 120 balloon restraint assembly

112. High area 121 restraint bar

113. First region 122 confinement rings

114. Second region 123 second tubular mesh structure

117. Main body part

Detailed Description

Example embodiments will now be described more fully with reference to the accompanying drawings. However, the exemplary embodiments can be embodied in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the example embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and thus a repetitive description thereof will be omitted. "or", "or" in the specification may each mean "and" or ". In the present invention, for one component, "distal" refers to the end that is distal from the operator and "proximal" refers to the end that is proximal to the operator. For example, in the view of fig. 1, the left side of the balloon is the distal end and the right side is the proximal end. The term "axial direction" in the present invention refers to the axial direction of the balloon, and for example, in the view of fig. 1, the left-right direction is the axial direction. The inner side and the outer side in the invention are relative to the axis of the balloon, the side close to the axis is the inner side, and the side far from the axis is the outer side.

The present invention provides a balloon catheter comprising: a balloon comprising a balloon body portion, the balloon having a compressed state and an expanded state; and a balloon constraining assembly comprising at least one constraining rod helically wound around at least a portion of an outer surface of the balloon body to form a helical structure extending in an axial direction of the balloon; at least a portion of the restraining bar is configured to radially restrain at least a portion of the balloon body portion when the balloon is in an expanded state. According to the invention, the constraint rod forms the spiral structure outside the balloon main body part, compared with other constraint structures, the spiral structure has better recoil, and meanwhile, the spiral structure extends and winds along the axial direction of the balloon part, so that constraint forces in different directions can be applied to the balloon part, the axial expansion of the balloon part is more sufficient, and the radial limitation of the expansion of the balloon is realized.

The balloon restraint assembly and balloon catheter structures of various embodiments of the present invention are described in detail below with reference to the drawings, and it should be understood that the various embodiments are not limiting upon the scope of the present invention.

In this embodiment, as shown in fig. 1, the balloon catheter 100 has a balloon 110 at the distal end and a single-layer double lumen tube at the proximal end of the catheter 100. The balloon 110 includes a balloon main body portion 117, two tube leg portions 119 located at both axial ends of the balloon main body portion 117, and two taper portions 118 connected between the two tube leg portions 119 and the balloon main body portion 117, respectively. The end of the dual lumen tube near the distal end of the catheter is connected to the leg 119 of the balloon 110 and the end of the dual lumen tube near the proximal end of the catheter is provided with a Y-tube mount. The balloon 110 is further provided with a layer of inner tube, the inner tube penetrates through the balloon 110, one end of the inner tube is connected with a distal tube leg 119, and the other end of the inner tube is connected with a double-cavity intraductal guide wire cavity. The balloon catheter also includes an outer tube connected to proximal tube leg 119. The inner tube surface inside balloon 110 is attached with two radiopaque marker development rings. The distal tube leg 119 of the balloon 110 is welded with the tip tube, and the tip tube is softer than the tube of the balloon 110, so that the blood vessel is not easily damaged; the tip tube is in a cone shape after being heat-set, so that the narrow blood vessel can be conveniently passed through. In this embodiment, the balloon 110 is manufactured by a hot blow molding method, and the main section of the balloon 110 is barrel-shaped after being inflated under pressure, and is similar to the shape of the inner cavity of a blood vessel. The balloon 110, the inner tube, the double-lumen tube and the like can be processed by nylon or polyether block amide or polyester polymer materials, and the radiopaque marker ring is processed by platinum-iridium alloy, gold or tungsten-gold and other materials. The outer diameter of the balloon 110 can be correspondingly adjusted to be 1mm-30mm according to different application scenes. The length of balloon 110 may be adjusted accordingly and may be 20mm-200mm. However, the invention is not limited thereto, and other sizes of the balloon 110 may be used.

As shown in fig. 1 and 2, the balloon catheter 100 further includes a balloon restraint assembly 120 for restraining inflation of the balloon 110, the balloon restraint assembly 120 including at least one restraint rod 121, the restraint rod 121 being helically wound around at least a portion of an outer surface of the balloon body 117 to form a helical structure extending in an axial direction of the balloon 110. At least a portion of the restraining bar 121 is configured to radially restrain at least a portion of the balloon body portion 117 when the balloon 110 is in an expanded state. The constraining rod 121 is at least spirally wound herein, meaning that the constraining rod 121 may be spirally wound around the outer surface of the balloon body 117 only, or around the outer surface of the taper 118 and/or tube leg 119 in addition to the balloon body 117. When the balloon 110 is inflated by pressurization, the spiral structure formed by the restraining rod 121 is expanded along with the inflation of the balloon 110, and the direction of the restraining force applied by the restraining rod 121 with the spiral structure to the balloon 110 is changed along with the change of the winding direction of the restraining rod around the balloon 110, so that the balloon 110 is subjected to restraining forces in different directions, and a more uniform expansion state is shown.

The number of restraining bars 121 is related to the diameter of balloon 110. The number of the restraining bars 121 is preferably at least two, and at least two of the restraining bars 121 are spirally wound in parallel on the outer surfaces of the balloon main body portion 117, the tube leg portion 119 and the taper portion 118. Here, parallel spiral winding means that the restraining bars 121 are spirally wound on the outer surface of the balloon 110 in the same bending direction, and the plurality of restraining bars 121 do not intersect at the balloon body portion 117. The inclination angle α of the restraining bar 121 with respect to the circumferential direction of the balloon main body 117 may be 0< α <90 °, or 90< α <180 °, and is specifically selected as needed. In this embodiment, the number of the restraining bars 121 may be selected to be 2 to 10. For example, 4 restraining bars 121 correspond to 1-4mm diameter balloons 110,6 restraining bars 121 correspond to 5-8mm diameter balloons 110. The number is given here by way of example only, and in other embodiments the restraining bar 121 may be selected to be other numbers, for example more than 10.

As shown in fig. 1, when the balloon 110 is in an expanded state, the outer surface of the balloon 110 is provided with the restraining bar and a recessed low area 111 is formed at the position of the limit ring. Thus, the balloon 110 constrained by the constraining rod 121 presents a concave-convex profile in the axial direction, i.e., the constrained region is discontinuous, so that the expansion of the vascular stenosis by the balloon 110 in the axial direction is more sufficient. The restraining bar 121 is preferably made of wire and is further preferably a memory wire, such as nitinol. After pressure release, the balloon restraint assembly 120 can not only rely on the memory property and high elasticity of the metal wire to rebound to a near initial state, but also the spiral structure of the balloon restraint assembly 120 can enable the balloon restraint assembly 120 to have better recoil. Thus, the helical design of the restraining bar 121 facilitates the distensibility and the recoil of the product. The two oval structures in fig. 1 near the restraining bar 121 represent the concave trace of the balloon 110, and the balloon 110 cannot be excessively inflated due to the limitation of the restraining bar 121, and the balloon 110 is concave to form the low area 111 where the restraining bar 121 is caught. The position where the restraining rod and the limit ring are not arranged forms a raised high area 112, and the vertical height difference between the high area 112 and the low area 111 is selected to be 0.01-1mm, but the invention is not limited thereto, and the actual vertical height difference can be selected according to the requirement. The vertical height of the balloon 110 at a location on the surface represents the radius of the radial cross-section of the balloon at that location.

As shown in fig. 1 and 2, in this embodiment, the balloon restraint assembly 120 further includes a plurality of restraining rings 122, the restraining rings 122 surrounding the outer surface of the balloon body portion 117, and the plurality of restraining rings 122 being aligned in the axial direction of the balloon 110. The plurality of restriction rings 122 are parallel to each other and the interval between adjacent two restriction rings 122 is the same. Each of the restraining rings 122 is provided throughout all of the restraining bars 121. The number of the restriction rings 122 is related to the axial length of the balloon body 117, and the longer the balloon body 117 is, the greater the number of the restriction rings 122 may be 1 to 100. For example, when the length of the balloon main body 117 is 20mm, 11 restriction rings 122 are provided, and when the length of the balloon main body 117 is 40mm, 21 restriction rings 122 are provided. The number of the limiting rings 122 is only an example, and the present invention is not limited thereto, and may be selected according to the needs in practical applications. At least a portion of the restraining bar 121 and the plurality of restraining rings 122 form a first tubular mesh structure configured to radially restrain at least a portion of the balloon body portion 117 when the balloon 110 is in the expanded state. When the balloon 110 is inflated, the restriction ring 122 is also radially expanded to be expanded from a curled state to a ring shape. The restraining ring 122 can restrain the position of the restraining rod 121, so as to improve the stability of the whole balloon restraint assembly 120.

As shown in fig. 1 and 2, the balloon restraint assembly 120 further includes two second tubular mesh structures 123, surrounding the outer sides of the two tube legs 119, respectively. Each of the second tubular mesh structures 123 comprises at least one turn of mesh. The diagonal lines of the respective meshes of the second tubular mesh structure 123 are parallel to the axial direction of the balloon 110. The number of the grids can be selected according to the needs, for example, 4-20 grids, but the invention is not limited thereto.

One end of the restraining bar 121 may be connected to the second tubular mesh structure 123, and the other end may be connected to one of the restraining rings 122. Specifically, the second tubular mesh structure 123 includes: a second tubular mesh structure 123 surrounding the outside of the tubular leg 119 distal of the balloon body portion 117; and a second tubular mesh structure 123 surrounding the outside of the tubular leg 119 proximal to the balloon body 117. The restraining bars 121 are divided into two types: a first restraining bar and a second restraining bar. Wherein both ends of the first restraining bar are respectively connected to the second tubular mesh structure 123 and the most proximal restraining ring 122. The second restraining bar is connected at both ends to the most distal restraining ring 122 and the second tubular mesh structure 123, respectively. In this embodiment, the first constraining rod and the second constraining rod are alternately helically wound around the outer surface of the balloon body 117. The second tubular mesh structure may provide good end fixation to the restraining bar.

In this embodiment, the restraining bar 121, the restraining ring 122 and the second tubular mesh structure 123 of the balloon restraint assembly 120 are each made of a wire, preferably a memory wire, such as a nitinol wire. The metal wire is obtained by a metal tube through a laser cutting mode, and the balloon restraint assembly 120 is subjected to post-treatment through processes such as acid washing, sand blasting, polishing and the like, so that each corner of the obtained balloon restraint assembly 120 is a rounded corner.

In this embodiment, the wires located outside the balloon body 117 include part of the wires of the restraining bar 121 and the wires of the restraining ring 122, which are trapezoidal in cross section. The wire of the restraining bar 121 and the wire of the restraining ring 122 located outside the balloon main body portion 117 are identical in cross-sectional shape and size. The trapezoid comprises a first base and a second base, and the length of the first base is smaller than that of the second base. The first base of the trapezoid is further from the surface of the balloon body portion 117 than the second base. Therefore, the shorter first bottom edge faces outward and away from the balloon body portion 117, and the longer second bottom edge is proximate to the surface of the balloon body portion 117, which increases the friction between the balloon restriction assembly 120 and the balloon body portion 117, reduces the displacement between the balloon restriction assembly 120 and the balloon body portion 117, and improves the stability of the entire balloon catheter 100.

In this embodiment, the wire cross section of the restraining bar 121 outside the taper 118 is gradually changed. Specifically, in the cross section of the wire of the restraining bar 121 located outside the taper portion 118, the length of the first bottom edge gradually increases to the length of the second bottom edge in the direction away from the balloon main body portion 117 and parallel to the axial direction, and correspondingly the cross-sectional area of the wire becomes larger. I.e. for the taper 118 on the right in fig. 1, the length of the first base of the cross section of the wire on its outside increases gradually from left to right to the length of the second base. For the taper 118 on the left in fig. 1, the length of the first base of the cross section of the wire on its outside increases gradually from right to left to the length of the second base. Thus, the cross section of the wire at the position where the taper portion 118 is away from the balloon main body portion 117 and the outside of the tube leg portion 119 is rectangular, and the tensile strength of the wire can be enhanced, and the wire can be prevented from breaking at the time of retraction.

In this embodiment, the second tubular mesh structure 123 is welded to the tubular leg 119 of the balloon 110. Specifically, the position of the tubular leg 119 of the balloon 110, to which the second tubular mesh structure 123 is attached, has a layer of welded tube, the welded tube is sleeved on the outer surface of the second tubular mesh structure 123, and the length of the welded tube is slightly greater than the axial diagonal length of the second tubular mesh structure 123. The second tubular mesh structure 123 is embedded in the welded tube by welding, and melted and reshaped with the tube leg 119 of the balloon 110 to form an integral structure. The welded pipe can also be processed by adopting nylon, polyether block amide or polyester polymer materials.

Conventional constraining products constrain only balloon body portion 117, ignoring the risk of over-inflation of taper portion 118 of balloon 110. In particular, the constrained product risks over-inflation or even bursting of the unconstrained cone 118 after constraining the balloon body 117. In this embodiment, the outer surface of the taper 118 is at least partially coated with a biocompatible glue layer. Specifically, as shown in fig. 3 and 4, the outer surface of the taper 118 includes a first region 113 coated with a biocompatible glue layer and a second region 114 not coated with the biocompatible glue layer. The biocompatible glue layer can be made of acrylic ester or polyurethane and other materials. The thickness of the biocompatible glue layer is 0.001mm-0.1mm, but the present invention is not limited thereto, and specific thickness values may be selected as needed. In this embodiment, by coating the taper 118 at least partially with the biocompatible glue layer, the first region 113 is stiffened in texture and has a reduced ability to expand, effectively preventing over-inflation of the taper 118, and improving the product performance of the balloon catheter 100.

The first region 113 may have a band shape, a dot shape, a ring shape, or the like. In this embodiment, as shown in fig. 4, the first region 113 is a band-shaped region extending from the distal end to the proximal end of the taper 118. The balloon 110 is preferably folded in three wings, or in five wings or six wings, and is positioned when folded, so that the first region 113 is uniformly positioned on one side or both sides of the wings, rather than at the folds of the wings. For example, the balloon 110 may be flap-positioned along the dashed lines in fig. 4 to avoid damage to the biocompatible glue layer. In this embodiment, the first regions 113 are uniformly distributed along the axial direction of the taper 118, for example, the first regions 113 and the second regions 114 are alternately arranged along the circumferential direction of the taper 118. The area of the first region 113 and the area of the second region 114 may be the same, or the area of the first region 113 may be greater than or less than the area of the second region 114.

In summary, the balloon restraint assembly adopting the embodiment has the following beneficial effects:

(1) When the balloon is inflated, the restriction ring on the surface of the balloon is inflated and expanded from a curled state, and the restriction rod is also inflated radially. The restraining rod and the limit ring are combined to form a first tubular grid structure, so that radial limitation on the main body part of the balloon can be further realized, and the balloon can be expanded more uniformly.

(2) The two outer sides of the two ends of the balloon are provided with the second tubular grid structures formed by the constraint rods, the two outer sides of the conical parts are provided with the spiral structures formed by the constraint rods, and the spiral structures at the outer sides of the conical parts can perform uncoiling movement along with the expansion of the balloon, so that the balloon bending caused by the overlarge constraint force of the balloon constraint component on the balloon is avoided, and the rewinding property of the balloon is facilitated during pressure relief. Because the direction of the restraining force applied by the restraining rod of the spiral structure to the balloon is changed continuously along with the change of the winding direction of the restraining rod around the balloon, the balloon can be subjected to restraining forces in different directions, and therefore a more uniform expansion state can be shown. When the confinement rings are fully deployed to a ring shape, the confinement ring dimensions are no longer changed and the confinement rods associated with the confinement rings are constrained and no longer expand. At this time, the restraining rod and the restraining ring play a restraining role, so that the effective length section of the balloon has the surface morphology of alternately appearing high and low areas, the balloon is prevented from being excessively inflated, and the phenomenon of dog bones is avoided.

(3) According to the embodiment, the biocompatible glue layer is locally added to the cone, the texture of the coating area is hardened, so that the expansion capacity of the cone is reduced, the binding effect of the cone is improved, the cone still maintains an obvious cone shape under larger pressure, the whole balloon is limited to expand, and the risk of over-expansion and even explosion of the cone is avoided.

(4) The second bottom edge of the longer wire is close to the outer side surface of the balloon main body part, friction force between the second bottom edge and the balloon main body part is increased, overall stability of the balloon catheter is improved, the first bottom edge of the taper wire is gradually increased to enable the section to be rectangular, tensile strength of the balloon restraint assembly is increased, and the balloon catheter can be retracted more easily after treatment is finished.

The foregoing is a further detailed description of the invention in connection with the preferred embodiments, and it is not intended that the invention be limited to the specific embodiments described. It will be apparent to those skilled in the art that several simple deductions or substitutions may be made without departing from the spirit of the invention, and these should be considered to be within the scope of the invention.

Claims

1. A balloon catheter, comprising:

2. The balloon catheter of claim 1, wherein the balloon restraint assembly further comprises a plurality of restraint rings spaced apart along the balloon axis and connected to the restraint rod;

3. The balloon catheter of claim 1, wherein the balloon further comprises two tube legs respectively communicating with the axial ends of the balloon body portion and two tapers respectively connecting the two tube legs with the balloon body portion.

4. The balloon catheter of claim 3, wherein the number of restraining bars is at least two, and the at least two restraining bars are spirally wound on the outer surfaces of the balloon body part, the tube leg part and the cone part in parallel, and the restraining bars form a second tubular grid structure on the outer surface of the tube leg part.

5. A balloon catheter according to claim 3, wherein the balloon restriction assembly is made of wire, the wire outside the balloon body portion and the taper is trapezoidal in cross section, a first base of the trapezoid is farther from the surfaces of the balloon body portion and the taper than a second base, and a length of the first base is smaller than a length of the second base.

6. The balloon catheter of claim 5, wherein the length of the first bottom edge gradually increases to the length of the second bottom edge in a cross section of the wire located outside the taper in a direction from the balloon body portion to the tube leg portion.

7. The balloon catheter of claim 1, wherein the balloon restraint assembly is made of a shape memory metal.

8. The balloon catheter of claim 3, wherein the outer surface of the taper comprises at least one region coated with a layer of glue.

9. The balloon catheter of claim 8, wherein the glue layer is evenly distributed along a circumference of the taper.

10. The balloon catheter of claim 8, wherein the layer of glue is a biocompatible material and has a thickness of 0.001mm to 0.1mm.

11. The balloon catheter of claim 1, wherein when the balloon is in the expanded state, a concave low region is formed at a position where the balloon restraint assembly is arranged on the outer surface of the balloon main body part, a convex high region is formed at a position where the balloon restraint assembly is not arranged, and a vertical height difference between the high region and the low region is 0.01mm-1mm.

12. The balloon catheter of claim 1, further comprising an inner tube extending through the balloon, a distal end of the inner tube being connected to a distal end of the balloon; and