CN113057717B

CN113057717B - Balloon catheter

Info

Publication number: CN113057717B
Application number: CN201911395976.2A
Authority: CN
Inventors: 周振标; 龙汉
Original assignee: Lifetech Scientific Shenzhen Co Ltd
Current assignee: Lifetech Scientific Shenzhen Co Ltd
Priority date: 2019-12-30
Filing date: 2019-12-30
Publication date: 2022-06-21
Anticipated expiration: 2039-12-30
Also published as: CN113057717A

Abstract

The invention relates to the field of medical instruments, and particularly provides a balloon catheter which comprises a balloon body, a cutting device and an elastic net bag, wherein two ends of the elastic net bag are connected with two ends of the balloon body, the cutting device is fixed on the outer surface of the elastic net bag, the elastic net bag is gradually expanded along with expansion of the balloon body, when the balloon body expands to the elastic limit of the elastic net bag, the balloon body continues to expand, and the shape of the elastic net bag is kept unchanged. When cutting device cuts certain degree of depth, the elastic action of elasticity string bag reaches the limit and keeps the shape unchangeable, this meeting of sacculus of continuing the expansion this moment forms a plurality of archs under the constraint effect of elasticity string bag, and cutting device keeps the position unchangeable under the effect of elasticity string bag, continue the expansion as the sacculus body, protruding contact blood vessel inner wall on the sacculus body when promoting blood vessel outwards expansion, cutting device withdraws from embolism department, the excessive cutting that leads to because of excessive expansion has been reduced, reach the effect of prevention excessive cutting.

Description

Balloon catheter

Technical Field

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

Background

Calcification and plaque growth exist in peripheral and coronary vessel lesions, when a medicine balloon is generally directly used in a heavily calcified or plaque-laden blood vessel, the foreign matters become barriers for medicine transmission to an intima of the blood vessel, a cutting balloon is commonly used at present to cut the calcification and plaque at a stenotic lesion part, then the medicine balloon is used, so 2 instruments are needed in the operation, the medicine attachment at the cut part cannot be guaranteed, and the medicine dosage at the cut part of the plaque is too small. The existing cutting balloons are divided into three types, one type is a single-wire cutting balloon (a guide wire is arranged on the surface of the balloon, and the guide wire is used for cutting calcification and plaque after the balloon is expanded), the other type is a spiral cutting balloon (one or more guide wires which are arranged on the surface of the balloon in a spiral mode are arranged on the surface of the balloon, and the guide wire is used for cutting calcification and plaque after the balloon is expanded). Compared with a single cutting path of the single wire cutting balloon, the cutting path of the single wire cutting balloon is replaced by other instruments, the ScoreflexNC high-pressure cutting balloon and the angioSculpt RX PTCA integral cutting balloon of Philips are arranged on the market at present, the balloons do not carry medicines, and all the cutting balloons can cause excessive cutting to damage blood vessels.

Disclosure of Invention

The present invention solves the above-mentioned technical problems in the related art at least to some extent. Therefore, the invention provides a balloon catheter which greatly reduces tissue damage caused by over-cutting.

In order to achieve the above object, a first aspect of the present invention provides a balloon catheter, including a balloon body, a cutting device, and an elastic string bag sleeved outside the balloon body, where two ends of the elastic string bag are connected to two ends of the balloon body, and the cutting device is fixed on an outer surface of the elastic string bag, where the elastic string bag is gradually expanded along with expansion of the balloon body, and when the balloon body expands to an elastic limit of the elastic string bag, the balloon body continues to expand, and a shape of the elastic string bag remains unchanged.

In addition, the balloon catheter according to the invention can also have the following additional technical features:

according to one embodiment of the invention, the elastic net bag comprises a first elastic belt arranged along the axial direction of the balloon body and a second elastic belt arranged along the circumferential direction of the balloon body, the first elastic belt and the second elastic belt are connected in a cross mode, and two ends of the first elastic belt are respectively connected with two ends of the balloon body.

According to one embodiment of the invention, the material of the elastic net bag is selected from elastic metal or elastic plastic.

According to an embodiment of the present invention, the first elastic belt and the second elastic belt are made of a material selected from an elastic metal or an elastic plastic.

According to one embodiment of the invention, the elastic metal is selected from nickel-titanium alloy, cobalt-chromium alloy, gold-cadmium alloy or copper-zinc alloy, and the elastic plastic is selected from polyurethane, latex, silica gel or nylon.

According to one embodiment of the present invention, the first elastic belt and the second elastic belt are in a sheet shape or a column shape.

According to one embodiment of the invention, the first elastic belt has a cross-sectional width of not more than 0.5 mm.

According to one embodiment of the invention, the cutting device comprises a cutting piece, and the section of the cutting piece perpendicular to the axial direction of the balloon body is triangular or trapezoidal.

According to one embodiment of the invention, the cutting device further comprises a supporting piece, the supporting piece is positioned between the balloon body and the cutting piece, two ends of the supporting piece are respectively connected with two ends of the cutting piece, and when the cutting piece is acted by a force towards the axis of the balloon body, the middle section of the supporting piece and the middle section of the cutting piece move relatively.

According to one embodiment of the invention, the cutting member defines an opening, the opening is loaded with a drug, and after the balloon body is expanded, the support member acts on the cutting member to release the drug from the opening.

According to one embodiment of the invention, the cutting member has a receiving cavity, part of the support member being located in the receiving cavity.

Compared with the prior art, the invention has the following beneficial effects:

through the elasticity string bag that is fixed with cutting device is established to the surface cover at sacculus body, the elasticity string bag struts along with the inflation of sacculus body gradually. When cutting device cuts certain degree of depth, the elastic action of elasticity string bag reaches the limit and keeps the shape unchangeable, this meeting of sacculus of continuing the expansion this moment forms a plurality of archs under the constraint effect of elasticity string bag, and cutting device keeps the position unchangeable under the effect of elasticity string bag, continue the expansion as the sacculus body, protruding contact blood vessel inner wall on the sacculus body when promoting blood vessel outwards expansion, cutting device withdraws from embolism department, the condition of the excessive cutting tissue that has significantly reduced leads to because of excessive expansion, reach the effect of prevention excessive cutting.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:

FIG. 1 is a perspective view of a balloon catheter in example 1 of the present invention;

FIG. 2 is a front view of a balloon catheter in accordance with embodiment 1 of the present invention;

FIG. 3 is an assembled view of the balloon body and the catheter body in example 1 of the present invention;

FIG. 4 is a perspective view of a balloon body in example 1 of the present invention;

FIG. 5 is a spreading view of a cutting apparatus in example 1 of the present invention;

FIG. 6 is a partial sectional view of a cutting device in embodiment 1 of the present invention;

FIG. 7 is a sectional view in the A-A direction of 4 sets of cutting devices in example 1 of the present invention;

FIG. 8 is a sectional view of a cutting device in the direction B-B in example 1 of the present invention;

FIG. 9 is a circumferential distribution diagram of 3 groups of cutting devices in a balloon body in example 1 of the invention;

FIG. 10 is a circumferential distribution of the balloon flaps on the inner tube of example 1 of the present invention;

FIG. 11 is a front view of a balloon catheter with a protective sheath according to example 1 of the present invention;

FIG. 12 is a sectional view in the A-A direction of a cutting device in embodiment 2 of the present invention;

FIG. 13 is a sectional view of a cutting device in the direction B-B in embodiment 2 of the present invention;

FIG. 14 is a sectional view in the A-A direction of a cutting device in embodiment 3 of the present invention;

FIG. 15 is a sectional view of a cutting device in the direction B-B in example 3 of the present invention;

FIG. 16 is a perspective view of a balloon catheter in accordance with example 4 of the present invention;

FIG. 17 is a front view of a balloon catheter in accordance with embodiment 4 of the present invention;

FIG. 18 is a spread view of the cutting means and the elastic string bag according to example 4 of the present invention;

FIG. 19 is a partial sectional view of a cutting device with an elastic string bag according to embodiment 4 of the present invention;

FIG. 20 is a sectional view in the A-A direction of the cutting device in embodiment 4 of the present invention;

FIG. 21 is a schematic view of the present invention (including but not limited to example 4) with a cutting device of different configuration for cutting open lesions;

FIG. 22 is a schematic view of a cutting device according to an embodiment of the present invention in a retracting manner;

FIG. 23 is a perspective view of a balloon catheter in accordance with example 5 of the present invention;

FIG. 24 is a front view of a balloon catheter in accordance with example 5 of the present invention;

FIG. 25 is a sectional view of a cutting device in embodiment 5 of the present invention;

fig. 26 is a cross-sectional view of 4 sets of cutting devices and a balloon body in the direction a-a in example 5 of the present invention;

FIG. 27 is a sectional view of 4 sets of cutting devices and an elastic string bag in the A-A direction according to example 5 of the present invention;

FIG. 28 is a spread view of the cutting means and the elastic string bag according to example 5 of the present invention;

FIG. 29 is a partial sectional view of a cutting device with an elastic string bag according to embodiment 5 of the present invention;

FIG. 30 is a cross-sectional view of a cutting device in accordance with another embodiment of the present invention;

FIG. 31 is a circumferential distribution diagram of the cutting device of FIG. 30 on a balloon body;

fig. 32 is a schematic view of a retracting manner of the cutting device in embodiment 5 of the present invention.

Detailed Description

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be 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 scope of the disclosure to those skilled in the art.

It is to be understood that the terminology used herein is for the purpose of describing particular example embodiments only, and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprising," "including," and "having" are inclusive and therefore specify the presence of stated features, elements, and/or components, but do not preclude the presence or addition of one or more other features, elements, components, and/or groups thereof.

In the description of the present invention, unless otherwise explicitly specified or limited, the terms "disposed" and "connected" are to be construed broadly, e.g., as meaning a fixed connection, a detachable connection, or an integral connection; may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first", "second", may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

For convenience of description, spatially relative terms, such as "bottom," "front," "upper," "oblique," "lower," "top," "inner," "horizontal," "outer," and the like, may be used herein to describe one element or feature's relationship to another element or feature as illustrated in the figures. This spatially relative relationship is intended to encompass different orientations of the mechanism in use or operation in addition to the orientation depicted in the figures. For example, if the mechanism in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" or "over" the other elements or features. Thus, the example term "below … …" can include both an orientation of above and below.

It should be noted that "distal" and "proximal" are used as terms of orientation that are commonly used in the field of interventional medical devices, wherein "distal" refers to the end that is distal from the operator during the procedure, and "proximal" refers to the end that is proximal to the operator during the procedure. Axial, meaning a direction parallel to the line connecting the center of the distal end and the center of the proximal end of the medical device; radial, meaning the direction perpendicular to the axial direction, the distance from the axis, and the distance to the axis along the radial direction.

Example 1

As shown in fig. 1-2, embodiment 1 of the present invention provides a balloon catheter 100, where the balloon catheter 100 includes a balloon body 101 and a plurality of cutting devices 11 located outside the balloon body 101, and the cutting devices 11 are arranged along an axial direction of the balloon body 101 and are spaced apart from each other in a circumferential direction of the balloon body 101.

As shown in fig. 3, the balloon catheter 100 further includes a catheter body, which includes an outer tube 102 and an inner tube 13, the outer tube 102 is connected to the proximal end of the balloon body 101, the inner tube 13 is disposed in the inner cavity of the outer tube 102, the inner tube 13 passes through the balloon body 101 and passes through the distal end of the balloon body 101, a gap exists between the outer tube 102 and the inner tube 13, and the balloon body 101 can be expanded or retracted by pressurizing or depressurizing the gap. In other embodiments, the catheter body may be a multi-lumen tube, and the balloon body 101 is communicated with one of the lumens, and the inflation or deflation of the lumen can realize the expansion or retraction of the balloon body 101.

Combine fig. 1 and fig. 3, when in actual use, carry out high pressure filling to sacculus body 101 inside, the inner wall pressurized inflation expansion of sacculus body 101, cutting device 11 produces deformation under the expansion of sacculus body 101 to the surface of hugging closely sacculus body 101 to cut pathological change tissue, after sacculus body 101 pressure release, cutting device 11 retracts along with sacculus body 101 together.

In this embodiment, both ends (proximal and distal ends) of the cutting device 11 are connected to both ends (proximal and distal ends) of the balloon body 101, respectively, and the cutting device 11 is not connected to the middle-section expansion surface (the region between the proximal and distal ends) of the balloon body 101. Because the cutting device 11 adopts a mode of fixing two ends, the cutting device 11 is not connected with the surface of the balloon body 101, glue does not need to be coated on the surface of the balloon body 101, and the thickness of the balloon body 101 can be properly reduced, so that the overall contour size of the system is reduced, and the capability of the balloon catheter 100 for passing through blood vessels is enhanced. In other embodiments, the middle section of the cutting device 11 may also be fixed to the middle section of the balloon body 101, and the present invention is not limited thereto, and those skilled in the art can flexibly select the cutting device as needed.

Further, as shown in fig. 4, the balloon body 101 includes a columnar expansion portion 1010 and two tapered necking portions 1011 connected to both ends of the expansion portion 1010, respectively, the outer tube 102 is connected to the necking portion 1011 at one end, and the inner tube 13 is inserted into the necking portion 1011 at one end and is inserted out of the necking portion 1011 at the other end. Balloon catheter

As shown in fig. 5-6, the cutting device 11 includes a supporting member 111 and a cutting member 112, wherein the supporting member 111 is located between the balloon body 101 and the cutting member 112, and the supporting member 111 and the cutting member 112 are movable relatively. Specifically, the supporting member 111 is located at a lower layer, the cutting member 112 is located at an upper layer, and both ends (proximal and distal ends) of the cutting member 112 are connected to both ends (proximal and distal ends) of the supporting member 111, respectively. The two ends of the supporting member 111 are connected to the necking portions 1011 at the two ends of the balloon body 101, respectively, but the bottom of the supporting member 111 may be completely fixed to the balloon body 101. In this embodiment, the opening 110 is opened on the cutting member 112, the opening 110 is loaded with the drug, and after the balloon body 101 is expanded, the supporting member 111 acts on the cutting member 112 to release the drug from the opening 110. The drug is not limited to a drug for treating vascular stenosis. In other embodiments, the cutting device 11 may not be provided with openings.

Referring to fig. 7, the cutter 112 has a receiving cavity 1120, and a portion of the support 111 is located in the receiving cavity 1120. When the balloon body 101 is expanded until the top end of the cutting piece 112 is contacted with the pathological tissue, the top end of the cutting piece 112 interacts with the pathological tissue to realize the first cutting action; the balloon body 101 is further expanded, the cutting part 112 keeps the position unchanged under the action of the lesion tissue, the supporting part 111 continues to be pushed towards the accommodating cavity 1120 of the cutting part 112 under the action of the expansion force of the balloon body 101, the pushing force acts on the cutting part 112, the cutting part 112 acts on the lesion tissue again, and the second cutting effect is achieved.

Support member 111 includes support member proximal end, support member distal end and is located the middle section between support member proximal end and the support member distal end, and cutting member 112 includes cutting member proximal end, cutting member distal end and is located the middle section between cutting member proximal end and the cutting member distal end, and when cutting member 112 received the effort towards sacculus body 101 axle center, the middle section of support member 111 and the relative motion of cutting member 112. Referring again to fig. 4-7, the support member 111 and the cutting member 112 each include a middle section 113 and two fixed sections 114, wherein the fixed sections 114 are proximal and distal ends of the support member 111 or proximal and distal ends of the cutting member 112. The fixing sections 114 of the supporting member 111 are respectively connected to the necking portions 1011 of the balloon body 101, the fixing sections 114 of the cutting member 112 are respectively connected to the fixing sections 114 of the supporting member 111, the accommodating cavity 1120 and the openings 110 are both disposed on the middle section 113 of the cutting member 112, and the openings 110 are axially distributed along the middle section 113 of the cutting member 112. The middle section 113 of the cutting member 112 interferes with, but is not connected to, the middle section 113 of the support member 111, and the top of the middle section 113 of the support member 111 is located in the receiving cavity 1120 of the middle section 113 of the cutting member 112.

In this embodiment, referring to fig. 1 and 5 again, the cutting device 11 may be a broken line segment which is distributed along the axial direction of the balloon body 101, and the broken line segment is understood as a broken line when viewed from the axial section after the linear fixing segments 114 at the two ends are connected with the linear middle segment 113. It will be appreciated that in other embodiments, the fixed segment 114 and the intermediate segment 113 may be respectively of a dogleg shape or a curved line shape, and the cutting device 11 may be distributed along a direction at any angle with respect to the axis of the balloon body 101. In addition, the inclination angles of the connecting lines at the two ends of each cutting device 11 with respect to the axial direction of the balloon body 101 may be the same or different. It is understood that the present embodiment does not limit the specific shapes of the supporting member 111 and the cutting member 112, as long as both ends of the supporting member 111 are fixed at the necked-down portions 1011, respectively, and both ends of the cutting member 112 are connected to both ends of the supporting member 111, respectively.

In this embodiment, as shown in fig. 7-8, the projection of the cutting element 112 on the surface of the balloon body 101 falls within the projection of the support element 111 on the surface of the balloon body 101. Specifically, the cross section of the supporting member 111 in the direction perpendicular to the axial direction of the balloon body 101 is triangular, and preferably isosceles triangular, the bottom surface of the supporting member 111 is used for being attached to the surface of the balloon body 101 when the balloon body 101 is expanded, the cross section of the cutting member 112 in the direction perpendicular to the axial direction of the balloon body 101 is inverted V-shaped, the two side surfaces of the cutting member 112 form accommodating cavities 1120 for accommodating part of the supporting member 111, and the openings 110 are opened in the two side surfaces of the cutting member 112. Push blocks 12 are respectively arranged on two outer side surfaces of the supporting piece 111 along a direction perpendicular to the axial direction of the balloon body 101, and the push blocks 12 are used for pushing the medicine out of the opening 110. In other embodiments, the cross-section of the support 111 perpendicular to the axial direction of the balloon body 101 may also be trapezoidal.

Further, with continued reference to fig. 7, the tip end surface 120 of the push block 12 can abut against the inner side surface of the cutter 112. In this embodiment, the top end surface 120 of the push block 12 is an inclined surface, and it should be noted that, when the balloon body 101 is not expanded, the cutting element 112 is covered on the top end of the supporting element 111, the top end of the supporting element 111 is located in the accommodating cavity of the cutting element 112, at this time, two inner side surfaces of the cutting element 112 are abutted against two outer side surfaces of the supporting element 111, and a part of the top end surface 120 of the push block 12 is abutted against the inner side surface of the cutting element 112 in parallel, and another part of the top end surface 120 of the push block 12 covers a part of the opening 110 for supporting the medicine in the opening 110. When the balloon body 101 is expanded, after the cutting member 112 finishes the first cutting, the cutting member 112 keeps the position unchanged under the action of the diseased tissue, the supporting member 111 drives the push block 12 to move upwards along the two inner side surfaces of the cutting member 112 under the action of the expansion force of the balloon body 101, which is equivalent to the action of the cutting member 112 towards the axis of the balloon body, until the push block 12 moves to the position below the opening 110, the push block 12 penetrates the opening 110 to push the medicine upwards from the opening 110, meanwhile, the supporting member 111 continues to push the accommodating cavity 1120 of the cutting member 112 to act on the cutting member 112, the cutting member 112 acts on the diseased tissue again, the second cutting is realized, then the medicine is released, the medicine can permeate into the inner wall of the blood vessel along the cut gap, and the utilization rate of the medicine is greatly improved.

It can be understood that, during the operation, the balloon body 101 needs to be protected by the delivery sheath until the lesion tissue is delivered, and then the delivery sheath is withdrawn, so that the supporting member 111 and the cutting member 112 can avoid the external force during the delivery process, and the supporting member 111 and the cutting member 112 can interact with each other, thereby releasing the drug, and simultaneously avoiding the cutting member 112 from damaging the blood vessel.

Further, in this embodiment, referring to fig. 5 and 6 again, the shape of the opening 110 on the surface of the cutting element 112 is selected from a rectangle, of course, the shape of the opening 110 may also be a circle, a triangle, or the like, and the shape of the opening 110 is not limited in this embodiment of the invention.

In this embodiment, referring to fig. 5 and 8 again, the cutting devices 11 may be arranged in 4 groups, that is, 4 supporting members 111 and 4 cutting members 112 are respectively arranged, and of course, the cutting devices 11 may also be arranged in 3 groups, as shown in fig. 9, that is, 3 supporting members 111 and 3 cutting members 112 are respectively arranged. The number of the cutting devices 11 is not limited in the embodiment of the present invention, and those skilled in the art can flexibly select the cutting devices as needed. Specifically, when the cutting devices 11 are arranged in 4 groups, the 4 groups of cutting devices 11 are all arranged along the axial direction of the balloon body 101 and are respectively and uniformly distributed along the circumferential direction of the balloon body 101 at intervals. It should be noted that the supporting member 111 and the cutting member 112 are made of elastic metal. In particular, the elastic metal may be selected from nickel titanium alloy, cobalt chromium alloy, gold cadmium alloy or copper zinc alloy.

Further, the balloon body 101 may be selected from semi-compliant balloons. Specifically, the semi-compliant balloon can be made of one or a mixture of more of nylon, Pebax, polyurethane, polyethylene terephthalate and polyethylene.

It should be noted that, as shown in fig. 10, the balloon catheter inner tube 13 is inserted into the balloon body 101, and the balloon body 101 has a plurality of balloon flaps 103 formed by winding around the outer wall surface of the inner tube 13.

Further, the plurality of balloon flaps 103 are wound counterclockwise along the outer wall surface of the inner tube 13. Of course, several balloon flaps 103 may be wound clockwise along the outer wall surface of the inner tube 13. Specifically, in the present embodiment, the number of balloon flaps 103 is 3, but in other embodiments, the number may not be limited to 3.

In order to achieve better drug administration effect, the surface of the balloon body 101 is provided with a drug coating. The drug coating may be selected from the group consisting of arterial stenosis drug coatings.

Referring to fig. 11, the balloon catheter 100 further includes a protective sheath 14 covering the cutting device 11. In particular, the protective sheath 14 may protect the balloon body 101 and the cutting device 11 from damage prior to delivery of the balloon catheter 100 into the body.

Example 2

The technical solution of this embodiment is substantially the same as embodiment 1, as shown in fig. 12-13, with reference to fig. 5, the difference is mainly that: the section of the middle section 113 of the supporting piece 111 in the axial direction perpendicular to the balloon body 101 is trapezoidal, the section of the cutting piece 112 in the axial direction perpendicular to the balloon body 101 is splayed, the section of the accommodating cavity 1120 in the axial direction perpendicular to the balloon body 101 is trapezoidal, the medicine is arranged in the accommodating cavity 1120, and the top opening of the cutting piece 112 is used as the opening 110.

The principle of the first cutting and the second cutting of the cutting member 112 in this embodiment is the same as that in embodiment 1, and this embodiment is not repeated herein, except that in the process of the first cutting and the second cutting of the cutting member 112, the supporting member 111 moves upward along the two inner side surfaces of the cutting member 112, and the therapeutic drug is pushed out from the opening 110 through the top end of the cutting member 112, so as to realize the first cutting and the second cutting, and then release the drug into the cut tissue.

Example 3

The technical solution of this embodiment is substantially the same as embodiment 1, as shown in fig. 14-15, with reference to fig. 5, the difference is mainly that: the section of the middle section 113 of the supporting piece 111 in the axial direction perpendicular to the balloon body 101 is triangular, the section of the cutting piece 112 in the axial direction perpendicular to the balloon body 101 is in a shape like a Chinese character 'ba', the section of the accommodating cavity 1120 in the axial direction perpendicular to the balloon body 101 is in an inverted funnel shape, and the top opening of the cutting piece 112 is used as the opening 110.

Specifically, with continued reference to fig. 15, when the balloon body 101 is not expanded, the cutting element 112 covers the top end of the supporting element 111, the top end of the supporting element 111 is located in the accommodating cavity 1120 of the cutting element 112, the therapeutic drug is placed in the accommodating cavity 1120, and at this time, two inner side surfaces of the cutting element 112 abut against two outer side surfaces of the supporting element 111.

The principle of the present embodiment that the cutting member 112 performs the first cutting, the second cutting and the administration simultaneously is the same as that of embodiment 2, and the description of the present embodiment is omitted.

Example 4

The technical solution of this embodiment is substantially the same as that of embodiment 1, and as shown in fig. 16, the differences mainly lie in: the surface of the balloon body 101 is sleeved with an elastic string bag 15, two ends of the elastic string bag 15 are respectively connected with the base pins of the catheter body (which means the joints between the inner tube and the outer tube and the balloon body 101, namely two ends of the balloon body 101), and the cutting device 11 is fixed on the outer surface of the elastic string bag 15.

Note that the middle portion of the elastic string bag 15 is not connected to the surface of the balloon body 101.

In this embodiment, as shown in fig. 17 to 18, the elastic tuck net 15 includes a first elastic strap 150 disposed along an axial direction of the balloon body 101 and a second elastic strap 151 disposed along a circumferential direction of the balloon body 101, the second elastic strap 151 is sleeved on the first elastic strap 150, the first elastic strap 150 and the second elastic strap 151 are cross-connected to form a cross-connection, two ends of the first elastic strap 150 are respectively connected to pins, and a bottom surface of the cutting device 11 is fixed on a surface of the first elastic strap 150. Specifically, as shown in fig. 19, a part of the bottom surface of the support 111 is fixed to the outer surface of the first elastic band 150, and another part of the bottom surface of the support 111 is fixed to the outer surface of the second elastic band 151 at a cross-connection. In other embodiments, the bottom surface of the cutting device 11 is fixed to the surface of the second elastic band 151, that is, arranged along the circumference of the balloon body 101; or a part of the bottom surface of the cutting device 11 is disposed along the axial direction of the balloon body 101 and is disposed on the surface of the first elastic band 150, and another part is disposed along the circumferential direction of the balloon body 101 and is disposed on the surface of the second elastic band 151.

Further, as shown in fig. 20, the cutting devices 11 on different first elastic bands 150 are evenly distributed along the circumference of the balloon body 101. Because the supporting members 111 are fixed on the first elastic belts 150, that is, the number of the first elastic belts 150 is 4, and the 4 first elastic belts 150 are uniformly distributed in the circumferential direction of the balloon body 101. In other embodiments, the number of the first elastic belts 150 is not limited to 4.

Specifically, the first elastic strap 150 and the second elastic strap 151 are made of elastic metal or elastic plastic, and are characterized in that the elasticity has a limit, and the elastic strap is not deformed when the elasticity reaches the limit, specifically, the elastic net bag 15 is gradually expanded along with the expansion of the balloon body 101, and when the balloon body 101 is expanded to the elastic limit of the elastic net bag 15, the balloon body 101 continues to expand, and the shape of the elastic net bag 15 is kept unchanged. The elastic metal can be selected from nickel-titanium alloy, cobalt-chromium alloy, gold-cadmium alloy or copper-zinc alloy, and the elastic plastic can be selected from polyurethane, latex, silica gel or nylon.

In addition, the first elastic belt 150 and the second elastic belt 151 are in a sheet shape or a column shape. And the width of the section of the first elastic belt 150 in the direction vertical to the axis of the balloon body 101 is not more than 0.5 mm.

Specifically, as shown in fig. 21, the balloon catheter 100 is delivered into the lumen 201 of the blood vessel 200, and lesion tissues such as emboli 300 are adhered to the inner wall of the blood vessel 200, wherein, under the expansion action of the balloon body 101, the surface of the balloon body 101 generates an outward pushing force on the first elastic band 150 and the second elastic band 151, and the first elastic band 150 and the second elastic band 151 deform along with the expansion of the balloon body 101 and cling to the surface of the balloon body 101. The cutting member 112 performs first cutting and second cutting on lesion tissues such as the embolism 300 under the expansion action of the balloon body 101, meanwhile, the supporting member 111 moves upwards along the accommodating cavity of the cutting member 112 to push the therapeutic drug 400 out of the opening, and the therapeutic drug 400 permeates along the cut gap to the inner wall of the blood vessel 200.

It should be noted that, as shown in fig. 22, when the cutting element 112 cuts to a certain depth (at this time, it is close to the inner wall of the blood vessel), the balloon body 101 continues to expand, because the elastic limit of the first elastic band 150 and the second elastic band 151 reaches the limit and is not elongated any more, the expanded balloon body 101 will form a plurality of similar rectangular protrusions 1012 under the constraint action of the first elastic band 150 and the second elastic band 151, and the cutting device 11 keeps the position unchanged under the action of the first elastic band 150 and the second elastic band 151, when the balloon body 101 continues to expand, the protrusions 1012 on the balloon body 101 contact the inner wall of the blood vessel and push the blood vessel to expand outward, the cutting device 11 exits from the embolism, thereby greatly reducing the over-cutting of the tissue of the blood vessel 200 caused by over-expansion, and achieving the effect of preventing over-cutting.

Example 5

The technical solution of this embodiment is substantially the same as embodiment 4, as shown in fig. 23 to 24, and the differences mainly lie in: unlike the double-layer cutting device 11 with the opening 110 in the embodiment 4, the cutting device 11 in the embodiment may be a single-layer cutting device without an opening, and specifically, as shown in fig. 25 to 29, a cross section of the cutting device 11 perpendicular to the axial direction of the balloon body may be a triangle, preferably an isosceles triangle, and a bottom surface of the isosceles triangle is connected with a surface of the elastic string bag 15.

It should be noted that in other embodiments of the present invention, as shown in fig. 30 to 31, the section of the cutting device 11 perpendicular to the axial direction of the balloon body may also be a trapezoid, preferably an isosceles trapezoid, and the width of the upper bottom surface of the isosceles trapezoid is not greater than the width of the lower bottom surface, and the lower bottom surface of the isosceles trapezoid is connected with the surface of the elastic string bag 15, and the upper bottom surface of the isosceles trapezoid serves as the cutting surface of the cutting device 11.

It should be noted that, as shown in fig. 32, when the degree of expansion of the balloon body is greater than the elastic limit of the first elastic band and the second elastic band, the principle of preventing the over-cutting in this embodiment is the same as that in embodiment 4, and the description of this embodiment is omitted.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent should be subject to the appended claims.

Claims

1. A balloon catheter is characterized by comprising a balloon body, a cutting device and an elastic net bag, wherein the elastic net bag is sleeved outside the balloon body, two ends of the elastic net bag are connected with two ends of the balloon body, the cutting device is fixed on the outer surface of the elastic net bag, the elastic net bag is gradually unfolded along with expansion of the balloon body, when the balloon body expands to the elastic limit of the elastic net bag, the balloon body continues to expand, and the shape of the elastic net bag is kept unchanged;

the cutting device comprises a cutting piece, and the section of the cutting piece, which is perpendicular to the axial direction of the balloon body, is triangular or trapezoidal;

the cutting device further comprises a supporting piece, the supporting piece is located between the balloon body and the cutting piece, two ends of the supporting piece are connected with two ends of the cutting piece respectively, and when the cutting piece is acted by an acting force towards the axis of the balloon body, the middle section of the supporting piece and the middle section of the cutting piece move relatively.

2. The balloon catheter according to claim 1, wherein the elastic net bag comprises a first elastic band arranged along an axial direction of the balloon body and a second elastic band arranged along a circumferential direction of the balloon body, the first elastic band and the second elastic band are connected in a cross manner, and two ends of the first elastic band are respectively connected with two ends of the balloon body.

3. The balloon catheter according to claim 1, wherein the elastic net bag is made of an elastic metal or an elastic plastic.

4. A balloon catheter according to claim 3, wherein said elastic metal is selected from nickel titanium alloy, cobalt chromium alloy, gold cadmium alloy or copper zinc alloy and said elastic plastic is selected from polyurethane, latex, silica gel or nylon.

5. A balloon catheter according to claim 2, wherein the first and second elastic bands are in the form of sheets or columns.

6. A balloon catheter according to claim 2, wherein the first elastic band has a cross-sectional width of no more than 0.5 mm.

7. The balloon catheter according to claim 1, wherein the cutting member defines an opening, the opening being loaded with a medicant, and wherein upon expansion of the balloon body, the support member acts on the cutting member to release the medicant from the opening.

8. A balloon catheter according to claim 1, wherein said cutting member has a receiving cavity, part of said support member being located within said receiving cavity.