CN113521505A

CN113521505A - Balloon catheter and preparation method thereof

Info

Publication number: CN113521505A
Application number: CN202010291236.0A
Authority: CN
Inventors: 李猛; 王钰富; 李俊菲
Original assignee: Shanghai Microport Medical Group Co Ltd
Current assignee: Shanghai Microport Medical Group Co Ltd
Priority date: 2020-04-14
Filing date: 2020-04-14
Publication date: 2021-10-22

Abstract

The invention relates to a balloon catheter and a preparation method thereof, the balloon catheter comprises a catheter body and a balloon, the balloon is sleeved on the catheter body and at least comprises a first balloon, a plurality of first micropores are formed in the first balloon, and blocking walls are arranged at the first micropores; after the saccule is expanded, the blocking wall inclines towards the corresponding first micropore to at least partially cover the first micropore, a liquid medicine channel is reserved between the blocking wall and the first micropore, and the extending direction of the liquid medicine channel is not vertical to the longitudinal axis of the saccule conduit. The invention buffers the liquid medicine through the baffle wall, thereby not only reducing the injection speed of the liquid medicine, but also changing the injection direction of the liquid medicine, further reducing the stimulation of the liquid medicine on blood vessels and reducing the occurrence of vasospasm.

Description

Balloon catheter and preparation method thereof

Technical Field

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

Background

Since the last 70 s of the century, the treatment of various cardiovascular diseases by interventional type medical devices has become increasingly common. And the rapid development of three milestones, namely, simple balloon dilatation (PTCA), a Bare Metal Stent (BMS) and a Drug Eluting Stent (DES) is performed in sequence. In particular, the advent of drug-coated stents has enjoyed great success in treating vascular stenosis, demonstrating the potential of DES in treating stenosis. At present, DES is the first choice for the treatment of obstructive coronary heart disease, but has the problems of late stent thrombosis, long vessel healing time, easy influence on vessel pulsation and the like. And DES applications are limited in-stent restenosis (ISR), small vessel lesions, and bifurcation lesions, in which case drug-coated balloons (DCB) are produced and show superior therapeutic efficacy.

The currently marketed drug balloon is coated with antiproliferative drugs on the surface of the balloon, and the balloon is pushed to a target lesion to expand the balloon to release the drugs when in use, and the drug balloon with the design faces the following challenges: (1) the medicine is easy to fall off and lose in the pushing process, so that the medicine dose is insufficient and even the fallen medicine can cause toxic and side effects; (2) the medicine coated on the surface of the medicine balloon is easy to form large medicine particles during expansion, so that far-end vascular embolism is easily caused, and high safety risk is realized; (3) the drug dose is not controllable and one balloon can only be used at one site. Aiming at the problems, people design a drug-filled balloon, namely, drug solution is injected from the inner cavity of the balloon and flows out through micropores on the surface of the balloon or other parts of the balloon, and the drug solution is absorbed by tissues.

Although the infusion of drug balloons solves some of the difficulties with drug coated balloons, the use of the balloon is still of concern due to its own design. In some current fill medicine sacculus, the liquid medicine can directly oppress and spray out through outer sacculus micropore, and nothing stops, and the liquid stream of high-speed injection can amazing the vascular wall, leads to vasospasm, and the safety risk is very big. In addition, the outflow fluid will diffuse outward disoriently, resulting in greater loss of the drug. In addition, some drug-filled balloons are also arranged, and the two ends of the drug-filled balloons swell up to block blood flow, so that the problem of loss of drug solution is solved, but blood is easy to remain at the closed two ends, thrombus is caused, and the risk is extremely high. In addition, if the pressure of the drug solution is reduced, the drug cannot be absorbed effectively, reducing the therapeutic effect.

Disclosure of Invention

The invention aims to provide a balloon catheter and a preparation method thereof, and aims to solve the problems that the existing drug-infused balloon is easy to cause vasospasm and thrombus, the loss of drug solution is high, the drug transfer efficiency is low and the like.

In order to achieve the above object, according to one aspect of the present invention, a balloon catheter is provided, which includes a catheter body and a balloon, wherein the balloon is sleeved on the catheter body, the balloon at least includes a first balloon, the first balloon is provided with a plurality of first micropores, and a blocking wall is arranged at the first micropores; after the saccule is expanded, the blocking wall inclines towards the corresponding first micropore to at least partially cover the first micropore, a liquid medicine channel is reserved between the blocking wall and the corresponding first micropore, and the extending direction of the liquid medicine channel is not perpendicular to the longitudinal axis of the saccule conduit.

Optionally, the distribution density of the first micropores at the proximal end of the balloon is higher than that of the first micropores at the distal end of the balloon; and/or the first micropores at the proximal end of the balloon have a larger pore size than the first micropores at the distal end of the balloon.

Optionally, after the balloon is expanded, the retaining wall near the proximal end of the balloon is inclined towards the proximal end of the balloon, and the remaining retaining wall is inclined towards the middle of the balloon.

Optionally, all of the retaining walls are inclined toward the middle of the balloon when the balloon is inflated.

Optionally, the barrier wall is configured to be changeable in position relative to the first micro-hole to adjust an extending direction of the liquid medicine passage.

Optionally, the blocking wall is formed by extending the hole wall of the corresponding first micropore outwards.

Optionally, the balloon further comprises a second balloon nested in the first balloon; the second balloon is provided with a plurality of second micropores; the catheter body having an inflation lumen;

the filling cavity is used for conveying liquid medicine to the second balloon to enable the balloon to be expanded, and the filling cavity is further used for conveying liquid medicine to the second balloon to enable the liquid medicine to flow into the first balloon through the second micropores under the action of pressure and then flow out of the first micropores.

Optionally, the plurality of second micropores and the plurality of first micropores are arranged in a staggered manner in the transverse direction of the balloon.

Optionally, the pore size range of the second micropores is 5.0 μm to 500 μm, and the pore size range of the first micropores is 5.0 μm to 800 μm.

Optionally, the balloon further comprises a second balloon nested in the first balloon; the catheter body is provided with a filling cavity and a drug delivery cavity which are isolated from each other;

the filling cavity is used for delivering filling medium to the second balloon to expand the balloon; the medicine feeding cavity is used for conveying liquid medicine to the first saccule, so that the liquid medicine flows out of the first saccule through the first micropores under the action of pressure.

To achieve the above object, according to one aspect of the present invention, there is provided a method of manufacturing a balloon catheter, comprising:

providing a catheter body and a balloon, and sleeving the balloon on the catheter body;

a plurality of micropores are formed in the balloon, and a blocking wall is arranged at each micropore;

the blocking wall is configured to incline towards the corresponding micropores to at least partially cover the micropores after the balloon is expanded, a liquid medicine channel is reserved between the blocking wall and the corresponding micropores, and the extending direction of the liquid medicine channel is not perpendicular to the longitudinal axis of the balloon catheter.

Optionally, in the preparation method, when the balloon is provided with micropores, the distribution density of the micropores at the balloon proximal end is higher than that of the micropores at the balloon distal end, and/or the pore diameter of the micropores at the balloon proximal end is larger than that of the micropores at the balloon distal end.

Optionally, in the preparation method, after the balloon is expanded, the blocking wall near the proximal end of the balloon is inclined towards the proximal end of the balloon, and the remaining blocking wall is inclined towards the middle of the balloon.

Optionally, in the preparation method, all the blocking walls are inclined towards the middle of the balloon after the balloon is expanded.

Optionally, in the method of making, the balloon diameter remains uniform after expansion.

Compared with the prior art, the balloon catheter and the preparation method thereof provided by the invention have at least one of the following advantages:

the sacculus pipe is provided with the fender wall in the first micropore department of first sacculus, and the accessible keeps off the wall and cushions the liquid medicine, has not only reduced the jet velocity of liquid medicine, but also has changed the injection direction of liquid medicine, can effectually block the stimulation of liquid stream to the vascular wall under the high pressure to the pouring of liquid medicine is accomplished to gentle mode, reduces the emergence of vasospasm.

The blocking wall is preferably inclined towards the middle of the balloon, so that the liquid medicine is sprayed towards the middle of the balloon, the diffusion direction of the liquid medicine is normalized, the loss of the liquid medicine flowing towards the two ends can be effectively reduced, and the medicine transfer rate is improved. Moreover, the expanded diameter of the first balloon is uniform, the front end and the rear end of a lesion part do not need to be blocked in the intervention process, the formation of thrombus by residual blood is avoided, and the safety of the instrument is improved. In addition, the position of the baffle wall relative to the first micropore is changeable, so that the spraying direction of the liquid medicine can be adjusted at any time, and the use is more flexible and convenient.

The first micropore's of sacculus near-end distribution density is higher than the first micropore's of sacculus far-end distribution density, perhaps, the first micropore's of sacculus near-end aperture is greater than the first micropore's of sacculus far-end aperture, and perhaps again, work as after the sacculus expansion, the fender wall that is close to the sacculus near-end inclines towards the sacculus near-end, and remaining fender wall inclines towards the sacculus middle part, and these modes homoenergetic make medicine evenly spread to the vascular wall, alleviate the influence that the sacculus near-end was washed by blood pressure and blood flow, reduce the loss of liquid medicine, further improve medicine transfer rate.

Drawings

It will be appreciated by those skilled in the art that the drawings are provided for a better understanding of the invention and do not constitute any limitation to the scope of the invention. In the drawings:

FIG. 1 is an axial cross-sectional view of a balloon catheter and its balloon when unexpanded, in accordance with a preferred embodiment of the present invention;

FIG. 2 is an enlarged partial view of the balloon catheter shown in FIG. 1;

FIG. 3 is an axial cross-sectional view of a balloon catheter and its balloon as expanded in accordance with a preferred embodiment of the present invention;

FIG. 4 is an enlarged partial view of the balloon catheter shown in FIG. 3;

FIG. 5 is an axial cross-sectional view of a balloon catheter and its balloon when unexpanded, as provided by a second preferred embodiment of the present invention;

FIG. 6 is an enlarged partial view of the balloon catheter shown in FIG. 5;

FIG. 7 is an axial cross-sectional view of a balloon catheter and its balloon as expanded, according to a second preferred embodiment of the present invention;

FIG. 8 is an enlarged partial view of the balloon catheter shown in FIG. 7;

fig. 9 is an axial sectional view of a balloon catheter and its balloon when expanded according to another preferred embodiment of the present invention.

In the figure:

balloon catheters

100, 200;

catheter bodies

110, 210; the

balloon

120, 220;

inner balloons

121, 221; the

outer balloon

122, 222; first micro-holes 124, 223; a second micro-hole 123; the

retaining walls

125, 224; a medical fluid passage 126.

The same or similar reference numbers in the drawings identify the same or similar elements.

Detailed Description

The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention. It should be noted that the drawings provided in the present embodiment are only for illustrating the basic idea of the present invention, and the components related to the present invention are only shown in the drawings rather than drawn according to the number, shape and size of the components in actual implementation, and the type, quantity and proportion of the components in actual implementation may be changed freely, and the layout of the components may be more complicated.

Furthermore, each of the embodiments described below has one or more technical features, and thus, the use of the technical features of any one embodiment does not necessarily mean that all of the technical features of any one embodiment are implemented at the same time or that only some or all of the technical features of different embodiments are implemented separately. In other words, those skilled in the art can selectively implement some or all of the features of any embodiment or combinations of some or all of the features of multiple embodiments according to the disclosure of the present invention and according to design specifications or implementation requirements, thereby increasing the flexibility in implementing the invention.

To further clarify the objects, advantages and features of the present invention, a more particular description of the invention will be rendered by reference to the appended drawings. It is to be noted that the drawings are in a very simplified form and are not to precise scale, which is merely for the purpose of facilitating and distinctly claiming the embodiments of the present invention. As used in this specification, the singular forms "a," "an," and "the" include plural referents unless the content clearly dictates otherwise. As used in this specification, the meaning of "a plurality" generally includes two or more unless the content clearly dictates otherwise. As used in this specification, the term "or" is generally employed in its sense including "and/or" unless the content clearly dictates otherwise. The term "axial" generally refers to a direction parallel to the longitudinal axis of the balloon catheter; "transverse" generally refers to a direction perpendicular to the axial direction; "proximal" generally refers to the direction of approach to the balloon catheter operator; "distal" refers to a direction away from the operator of the balloon catheter. It is also to be understood that the present invention repeats reference numerals and/or letters in the various embodiments. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. It will also be understood that when an element is referred to as being "connected" to another element, it can be directly connected to the other element or one or more intervening elements may be present.

The core idea of the invention is to provide a balloon catheter, which comprises a catheter body and a balloon, wherein the balloon is sleeved on the catheter body and at least comprises a first balloon, a plurality of first micropores are formed in the first balloon, and blocking walls are arranged at the first micropores. In practical operation, after the balloon is expanded, the blocking wall inclines towards the corresponding first micropore to at least partially cover the first micropore, a liquid medicine channel is reserved between the blocking wall and the corresponding first micropore, and the extending direction of the liquid medicine channel is not perpendicular to the longitudinal axis of the balloon catheter; by means of the arrangement, when the medical balloon is in a working state, under the pressure of the medicine, the medicine liquid in the first balloon flows out of the first micropores and is then sprayed out to the blood vessel through the medicine liquid channel, and the spraying direction of the medicine liquid is not perpendicular to the longitudinal axis of the balloon catheter. Therefore, the balloon catheter can buffer the liquid medicine through the baffle wall, reduce the injection speed of the liquid medicine, and change the injection direction of the liquid medicine at the same time, so that the injection direction of the liquid medicine is not vertical to the blood vessel wall any more, thereby completing the perfusion of the liquid medicine in a mild way, reducing the stimulation to the blood vessel wall and reducing the occurrence of vasospasm.

It will be appreciated that the balloon of the present invention may be a single layer balloon or a double layer balloon. When the sacculus is the individual layer sacculus, the pipe body only has one and fills sufficient chamber for to the inside liquid medicine of carrying of sacculus, make the sacculus expansion, after the expansion, under the pressure effect, the liquid medicine further flows out from the micropore on the sacculus and gets into the blood vessel. When the sacculus is the double-layer sacculus, the sacculus includes interior sacculus and outer sacculus, interior sacculus cover is located in the outer sacculus. In an optional scheme, a plurality of first micropores have been seted up on the outer sacculus, simultaneously a plurality of second micropores have been seted up on the interior sacculus, at this moment, the pipe body only has one and is full of the chamber, full chamber be used for to interior sacculus carries the liquid medicine, makes interior sacculus and outer sacculus expansion, after the expansion, under the pressure effect, the liquid medicine again flows into through a plurality of second micropores outer sacculus, and the rethread is a plurality of first micropore flows outer sacculus and gets into the blood vessel. In another optional scheme, only a plurality of micropores (namely, first micropores) are formed in the outer balloon, and no micropore is formed in the inner balloon, at this time, the catheter body is provided with a filling cavity and a medicine feeding cavity which are mutually isolated, filling media (such as contrast liquid) are conveyed to the inner balloon through the filling cavity, the inner balloon and the outer balloon are expanded, after expansion, liquid medicine is conveyed to the outer balloon through the medicine feeding cavity, and under the pressure action of the liquid medicine, the liquid medicine flows out of the outer balloon through the micropores and enters a blood vessel. Here, it should be understood that "micro-holes" refer to holes having a size of the order of micrometers, and the shape of micro-holes is not limited in the present invention, and circular micro-holes are preferable for convenience of processing.

In addition, the inner and outer balloons of the present invention are made of non-compliant or semi-compliant materials that do not expand with increasing pressure after expanding to a given size with increasing pressure. Adopt non-compliance or semi-compliance material, prevented hindering the medicine absorption after sacculus and vascular wall laminating, improved the medicine absorptivity. When the balloon is a single-layer balloon, the balloon preferably has a uniform diameter after expansion; similarly, when the balloon is a double-layer balloon, the diameter of the expanded outer balloon is preferably uniform; so set up, need not the front and back end shutoff with the pathological change position among the intervention process, avoided remaining blood to form the thrombus, improved the security of apparatus.

The balloon catheter and the method for manufacturing the same according to the present invention will be further described with reference to the drawings and the preferred embodiments, so as to highlight the features and characteristics of the above embodiments.

Example one

Fig. 1 is an axial sectional view of a balloon catheter and a balloon thereof according to a first preferred embodiment of the present invention, in which the balloon catheter and the balloon thereof are not expanded, fig. 2 is a partially enlarged view of the balloon catheter shown in fig. 1, fig. 3 is an axial sectional view of the balloon catheter and the balloon thereof according to a first preferred embodiment of the present invention, in which the balloon catheter and the balloon thereof are expanded, and fig. 4 is a partially enlarged view of the balloon catheter shown in fig. 3.

As shown in fig. 1 to 4, the present embodiment provides a balloon catheter 100, which includes a catheter body 110 and a balloon 120, where the balloon 120 includes an inner balloon 121 (i.e., a second balloon) and an outer balloon 122 (i.e., a first balloon), the inner balloon 121 and the outer balloon 122 are sequentially sleeved on the catheter body 110 from inside to outside, and after expansion, a gap exists between the outer balloon 122 and the inner balloon 121, that is, an expanded diameter of the outer balloon 122 is greater than an expanded diameter of the inner balloon 121, so as to avoid the inner balloon 121 and the outer balloon 122 from being attached to each other during expansion, prevent a first micropore on the outer balloon 122 from being blocked by the inner balloon 121, and ensure that a drug smoothly overflows. Optionally, the outer balloon 122 and the inner balloon 121 have expanded diameters that differ by 0.05mm to 5.0mm, and more preferably, by 0.1mm to 1.0mm, at a nominal pressure.

In addition, the outer balloon 122 is provided with a plurality of first micropores 124, the diameter of the first micropores 124 is preferably 5.0 μm to 800 μm, more preferably the diameter of the first micropores 124 is 10.0 μm to 200 μm, and still more preferably the diameter of the first micropores 124 is 10.0 μm to 100 μm. The diameter of the first micro-hole 124 is not too small, and the first micro-hole 124 is also easy to block large-particle drugs, and compared with the second micro-hole 123, the diameter of the first micro-hole 124 can be larger, which is beneficial to reducing the speed of spraying the liquid medicine and reducing the stimulation to blood vessels. The number of the first micro holes 124 is not limited in the present invention, and the distribution manner of the first micro holes 124 is not limited, and may be uniform distribution or non-uniform distribution. In this embodiment, the first micropores 124 are uniformly arranged about the longitudinal axis of the outer balloon 122, and are disposed in several layers along the longitudinal axis.

The inner balloon 121 is provided with a plurality of second micropores 123, and the diameter of the second micropores 123 is preferably 5.0 to 500 μm, more preferably 5.0 to 200 μm, and still more preferably 5.0 to 50 μm. Here, the diameter of the second micropores 123 should not be too large, too small, and too small will easily block the large-particle drug, and too large will affect the effective expansion of the inner balloon 121. The number of second micropores 123 and the distribution manner of second micropores 123 are not limited in the present invention, and may be uniformly distributed or non-uniformly distributed. In this embodiment, the second micropores 123 are uniformly arranged around the longitudinal axis of the inner balloon 121, and are provided with several layers along the longitudinal axis.

An inflation lumen (not shown) is provided in the catheter body 110 for the passage of the medicant solution through the inflation lumen to the inner balloon 121. Specifically, after the liquid medicine enters the inner balloon 121 through the catheter body 110, the inner balloon 121 and the outer balloon 122 are expanded, after the expansion, the liquid medicine is continuously filled into the inner balloon 121, the liquid medicine is pressurized by the liquid medicine, flows into the outer balloon 122 through the second micropores 123 on the inner balloon 121, overflows into the blood vessel from the first micropores 124 on the outer balloon 122, and due to the buffering effect of the outer balloon 122, the liquid medicine is prevented from being directly sprayed into the blood vessel at a high speed, the stimulation effect on the blood vessel is reduced, and the occurrence of vasospasm is reduced.

Further, the inventors considered that the effect is not obvious by buffering the liquid medicine only by the outer balloon 122, and the liquid medicine is still highly irritating to the blood vessel wall because not only the ejection speed of the liquid medicine at the first micropores 124 is high, but also the direction in which the liquid medicine is ejected from the first micropores 124 is perpendicular to the blood vessel wall. To this end, the balloon catheter 100 of the present embodiment is further provided with a barrier wall 125 at the first micro-hole 124. As shown in fig. 3 and 4, after the balloon 120 is expanded (i.e., the balloon 120 is tightly attached to the blood vessel wall), the blocking wall 125 is inclined toward the corresponding first micro hole 124 to at least partially cover the first micro hole 124, and the inclination angle α of the blocking wall 125 (i.e., the included angle between the blocking wall 125 and the longitudinal axis of the balloon) is greater than 0 ° and less than 90 °, at this time, a liquid medicine channel 126 (see fig. 4) is reserved between the blocking wall 125 and the corresponding first micro hole 124, and the extending direction of the liquid medicine channel 126 is not perpendicular to the longitudinal axis of the balloon catheter, so that, under the pressure of the medicine, the liquid medicine flows out between the inner balloon 121 and the outer balloon 22 through the second micro hole 123 on the inner balloon 121, and then flows out into the blood vessel from the first micro hole 124 on the outer balloon 122 and through the liquid medicine channel 126, during this process, the liquid medicine will pass through the buffering effect of the outer balloon 122 and the blocking wall 125, so that the speed of the liquid medicine sprayed at the first micro hole 124 becomes smaller, and the direction that makes the liquid medicine follow first micropore 124 department and flow out no longer is perpendicular to the vascular wall, so set up, can effectually block the stimulation of liquid stream to the vascular wall under the high pressure to the perfusion of liquid medicine is accomplished to mild mode, reduces the emergence of vasospasm. It should be understood that the arrows shown in fig. 3 represent the flowing direction of the liquid medicine.

More specifically, when the medical fluid is filled into the inner balloon 121, the inner balloon 121 is gradually expanded until the outer balloon 122 is tightly attached to the blood vessel wall, and then the medical fluid is continuously filled into the inner balloon 121, and under the action of pressure, the medical fluid flows out between the inner balloon 121 and the outer balloon 22 through the second micropores 123 on the inner balloon 121, and then flows out into the blood vessel from the first micropores 124 on the outer balloon 122 through the medical fluid passage 126, in the process, the outflow direction of the medical fluid is defined through the medical fluid passage 126, and the extension direction of the medical fluid passage 126 may be fixed and may also change with the change of the pressure, for example, the inclination angle α is larger as the medical pressure increases, whereas the inclination angle α is reduced as the medical pressure decreases, and correspondingly, the extension direction of the medical fluid passage 126 changes with the change of the inclination angle α. While the extending direction of the medical fluid passage 126 is kept constant, in this embodiment, the blocking wall 125 may be configured to be fixed to the outer balloon 122 at a constant position relative to the first micro-hole 124. When the extending direction of the liquid medicine channel 126 is changeable, in this embodiment, the position of the blocking wall 125 relative to the first micro-hole 124 is changeable, so that the blocking wall can be movably disposed on the outer balloon 122, and at this time, the inclination angle of the blocking wall 125 can be adjusted in real time through the medicine pressure, so as to adjust the spraying speed and the spraying direction of the liquid medicine at the first micro-hole 124 at any time, which is more flexible and more convenient for use.

In more detail, when the balloon 120 is not expanded, the blocking walls 125 are in a closed state, and at this time, the blocking walls 125 may be parallel to the longitudinal axis of the balloon 120 or may be expanded inward or outward, as shown in fig. 1 and 2; during or after the balloon 120 is expanded, as shown in fig. 3 and 4, the blocking wall 125 is pushed by the liquid medicine to further open outwards, and at this time, the blocking wall 125 extends towards the outside of the balloon 120 and forms the aforementioned inclination angle α, so that when the liquid medicine enters the first micropores 124, the blocking wall 125 at the first micropores 124 can further buffer the liquid medicine and change the spraying direction of the liquid medicine. It should be understood that herein, "the walls 125 are flared inward" means that the walls 125 extend away from the longitudinal axis of the balloon in a direction closer to the longitudinal axis of the balloon; by "the walls 125 flare outwardly" is meant that the walls 125 extend away from the longitudinal axis of the balloon.

In this embodiment, the blocking wall 125 may completely cover the corresponding first micro-hole 124, i.e., the first micro-hole 124 is not visible when viewed from a direction perpendicular to the axis of the balloon 120. In an alternative embodiment, the blocking wall 125 may also expose a portion of the corresponding first micro-hole 124, i.e., only a portion of the first micro-hole 124 is visible when viewed from a direction perpendicular to the axis of the balloon 120. Further, the blocking wall 125 is integrally formed with the outer balloon 122, for example, the outer balloon 122 can be directly pierced by a needle, on one hand, the first micropores 124 are formed by needle punching, and on the other hand, a part of the outer balloon 122 connected with the first micropores 124 forms the blocking wall 125, that is, a part of the outer balloon material on the wall of the first micropores 124 is retained to form the outward extending blocking wall 125, so that the manufacturing is simple and the processing cost is low. In other embodiments, the blocking wall 125 and the outer balloon 122 may be formed separately, for example, the first micropores 124 are formed on the outer balloon 122, and then the thin sheet-type blocking wall 125 is bonded to the first micropores 124, in which case, the material of the blocking wall 125 is preferably the same as that of the outer balloon 122.

In addition, after the balloon 120 is expanded, all the blocking walls 125 preferably incline toward the middle of the balloon 120, that is, extend toward the transverse central axis of the balloon 120, so that the liquid medicine can be sprayed toward the middle of the balloon 120 (see fig. 3), thereby normalizing the diffusion direction of the liquid medicine, effectively reducing the loss of the liquid medicine flowing toward the two ends of the balloon, and improving the medicine transfer rate. In addition, in the process of filling the liquid medicine, the inner balloon 121 is always kept in the expanded state, and the liquid medicine is continuously filled into the inner balloon 121, so that the continuous filling of the medicine is realized, the absorption rate of the medicine can be improved, and the treatment effect is improved. In addition, the expanded diameter of the outer balloon 122 is preferably uniform, i.e. the diameters of the two ends of the outer balloon 122 are the same as the diameter of the middle part of the outer balloon, so that the front end and the rear end of a lesion part do not need to be blocked in the interventional process, the formation of thrombus by residual blood is avoided, and the safety of the instrument is improved. The outer balloon 122 is cylindrical in shape after expansion, and has a good wall-adhering effect. The shape of the inner balloon 121 is not limited in the present invention, and the diameters of both ends of the inner balloon 121 may be the same as or different from the diameter of the middle portion of the inner balloon, and preferably the diameter of the expanded inner balloon 121 is uniform. Accordingly, the inner balloon 121 is also cylindrical in shape as a whole after expansion. It should be understood that the middle of the balloon (i.e., the medial transverse axis of the balloon) should not be narrowly construed as an absolute neutral position, and in some cases, includes positions that are offset from the neutral position. Furthermore, it should also be understood that when first micropores 124 are open exactly on the lateral central axis of the balloon, the barrier wall 125 may be disposed only on one side of the lateral central axis, and preferably the barrier wall 125 is inclined toward the lateral central axis.

Further, in order to better block the liquid medicine, the second micropores 123 on the inner balloon 121 and the first micropores 124 on the outer balloon 122 are arranged in a staggered manner in the lateral direction of the balloon (that is, at different axial positions), so that the liquid medicine can be blocked by the wall of the outer balloon 122 after flowing out of the second micropores 123, and the purpose of buffering is achieved. Further, in this embodiment, the first micropores 124 are uniformly arranged around the longitudinal axis of the outer balloon 122, and a plurality of layers are disposed along the longitudinal axis, in this case, it is preferable that the blocking wall 125 is uniformly arranged around the longitudinal axis of the outer balloon 122, and a plurality of layers are disposed along the longitudinal axis, and the blocking wall 125 is inclined toward the middle of the balloon, so that the liquid medicine ejected from each first micropore 124 is ejected toward the middle of the balloon at 360 degrees, and the medicine transfer efficiency is high.

In further embodiments, the catheter body 110 may be a single lumen or multi-lumen tube and provides an inflation lumen and a guidewire lumen therein. The distal end of the filling lumen has at least one infusion port in communication with the interior of the inner balloon 121. The distal end of the catheter body 110 is provided with visualization markers for marking the position of the proximal and distal ends of the balloon. In addition, both inner balloon 121 and outer balloon 122 may be formed of a non-compliant or semi-compliant material.

The invention does not limit the kind of the drug in the drug solution, and can be selected according to the actual requirement, such as antiproliferative drugs, anti-inflammatory drugs, antiproliferative drugs, antibacterial drugs, anti-tumor drugs, anti-mitotic drugs, cytostatic drugs, cytotoxic drugs, anti-osteoporosis drugs, anti-angiogenesis drugs, anti-restenosis drugs, microtubule-inhibiting drugs, anti-metastatic drugs or anti-thrombus drugs, etc. Drugs include, but are not limited to, the following: dexamethasone, prednisolone, corticosterone, budesonide, estrogen, sulfasalazine, aminosalicylic acid, acemetacin, escin, aminopterin, antimycotics, arsenic trioxide, aristolochic acid, aspirin, mini base, gingkolic acid, rapamycin and derivatives thereof (including zotarolimus, everolimus, bimesoximes, 7-O-desmethylrapamycin, temsirolimus, diphospholimus, etc.), endostatin, angiostatin, angiopeptin, monoclonal antibodies capable of blocking smooth muscle cell proliferation, levofloxacin, paclitaxel, docetaxel, hydroxycamptothecin, vincristine, doxorubicin, 5-fluorouracil, cisplatin, thymidine kinase inhibitor antibiotics (particularly actinomycin-D), hormones, antibody carcinostatics, bisphosphonates, selective estrogen receptor modulators, Strontium ranelate, cyclosporine A, cyclosporine C and brefeldin A; combinations of these agents are also possible.

The working principle of the balloon catheter 100 of the present embodiment will be further described with reference to the preferred embodiments. First, the balloon 120 is expanded: the liquid medicine (containing medicine) is conveyed to the inner balloon 121 through the filling cavity of the catheter body 110, so that the inner balloon 121 is gradually expanded, and the outer balloon 12 is also expanded until the outer balloon 122 is tightly attached to the wall of the blood vessel, so that the narrow diseased region is expanded. Then, spraying a liquid medicine: after the balloon 120 is expanded, the liquid medicine is continuously delivered to the inner balloon 120, so that the liquid medicine flows out to the outer balloon 122 through the second micropores 123 on the inner balloon 121 under the action of pressure, further flows out to the blood vessel through the first micropores 124 on the outer balloon 122 under the action of pressure and flows out from the liquid medicine channel 126. After the treatment is completed, the medical solution is withdrawn to retract the balloon 120, and the balloon catheter 100 is withdrawn from the body.

Example two

Fig. 5 is an axial sectional view of a balloon catheter and a balloon thereof according to a second preferred embodiment of the present invention, the balloon catheter being not expanded, fig. 6 is a partially enlarged view of the balloon catheter of fig. 5, fig. 7 is an axial sectional view of the balloon catheter and the balloon thereof according to the present embodiment, and fig. 8 is a partially enlarged view of the balloon catheter of fig. 7.

As shown in fig. 5 to 8, the present embodiment provides a balloon catheter 200, which includes a catheter body 210 and a balloon 220, wherein the balloon 220 includes an inner balloon 221 and an outer balloon 222, the inner balloon 221 and the outer balloon 222 are sequentially sleeved on the catheter body 210 from inside to outside, and after expansion, a gap exists between the outer balloon 222 and the inner balloon 221, that is, the expanded diameter of the outer balloon 222 is greater than the expanded diameter of the inner balloon 221, so as to avoid the inner balloon 221 and the outer balloon 222 from being attached to each other during expansion, prevent a first micropore on the outer balloon 222 from being blocked by the inner balloon 221, and ensure smooth overflow of a drug. Optionally, the expanded diameters of the outer balloon 222 and the inner balloon 221 differ by 0.05mm to 5.0mm at nominal pressure, and more preferably, the expanded diameters differ by 0.1mm to 1.0 mm.

Unlike the first embodiment, the inner balloon 221 is not provided with micropores (i.e. is isolated from the outer balloon 222), but only the outer balloon 222 is provided with a plurality of first micropores 223, the diameter of the first micropores 223 is preferably 5.0 μm to 800 μm, more preferably the diameter of the first micropores 223 is 10.0 μm to 200 μm, and still more preferably the diameter of the first micropores 223 is 10.0 μm to 100 μm. The number of the first micro holes 223 is not limited, and the distribution mode of the first micro holes 223 is not limited, and the first micro holes may be uniformly distributed or non-uniformly distributed. In this embodiment, the first micropores 223 are uniformly arranged around the longitudinal axis of the outer balloon 222, and are provided with several layers along the longitudinal axis. In the balloon catheter 200 of the present embodiment, the first micropores 223 are also provided with the blocking walls 224. The embodiment of the blocking wall 224 is the same as the first embodiment and will not be described in detail.

In addition, the catheter body 210 is provided with an inflation lumen (not shown) and a drug administration lumen (not shown) which are isolated from each other. The inflation lumen is in communication with the inner balloon 221 and the administration lumen is in communication with the space between the outer balloon 222 and the inner balloon 221. The administration lumen may enclose the filling lumen. The specific working principle is as follows: will fill up medium (preferred contrast medium) and carry to interior sacculus 221 through filling the chamber, make interior sacculus 221 and outer sacculus 222 expansion, until outer sacculus 222 and vascular wall closely laminate, after the expansion, pass through the liquid medicine the chamber of dosing is carried continuously to between interior sacculus 221 and the outer sacculus 222, receive liquid medicine pressure, the liquid medicine overflows to the blood vessel through first micropore 223 on the outer sacculus 222 in, this in-process, the liquid medicine can pass through outer sacculus 222 and keep off the cushioning effect of wall 224, make the speed that the liquid medicine sprays at first micropore 223 diminish, and make the direction that the liquid medicine flows out from first micropore 223 no longer perpendicular to vascular wall, so set up, can effectually block the stimulation of high pressure liquid flow to the vascular wall, accomplish the pouring of liquid medicine with gentle mode, reduce the emergence of vasospasm. It should be understood that the arrows shown in fig. 7 represent the flow direction of the liquid medicine and the flow direction of the filling medium, respectively. In addition, after the liquid medicine infusion is completed, the filling medium is pumped back to retract the balloon 220, and finally the balloon catheter 200 is withdrawn from the body.

In this embodiment, the distal end of the administration lumen has at least one administration port in communication with the space between the outer balloon 222 and the inner balloon 221. The inflation medium is preferably a contrast agent to visualize the position of the balloon by the contrast agent.

Other structures are basically the same as those of the first embodiment, and detailed description is omitted here, and specific reference may be made to implementation manners in the first embodiment.

EXAMPLE III

The embodiment provides a method for preparing a balloon catheter, which is used for preparing the balloon catheter described in the first embodiment or the second embodiment and can also be used for preparing a balloon catheter with a single-layer balloon.

When the balloon catheter with the single-layer balloon is prepared, a catheter body and the single-layer balloon are firstly provided, the single-layer balloon is sleeved on the catheter body, then a plurality of micropores are formed in the single-layer balloon, a blocking wall is arranged at each micropore, the blocking wall is configured to incline towards the corresponding micropore after the single-layer balloon is expanded so as to at least partially cover the micropore, a liquid medicine channel is reserved between the blocking wall and the corresponding micropore, and the extending direction of the liquid medicine channel is not perpendicular to the longitudinal axis of the balloon catheter.

When preparing the sacculus pipe of double-deck sacculus, provide pipe body and double-deck sacculus earlier, double-deck ball includes interior sacculus and outer sacculus, and set up a plurality of first micropores on the outer sacculus, and set up a plurality of second micropores on the interior sacculus, and at every first micropore department sets up a fender wall, then, and will interior sacculus and outer sacculus overlap in proper order and establish on the pipe body, wherein, will keep off the wall configuration and work as after the expansion of double-deck sacculus towards corresponding first micropore slope and at least partial cover first micropore, and keep off the wall with reserve the liquid medicine passageway between first micropore, and make the extending direction of liquid medicine passageway is out of plumb with the longitudinal axis of sacculus pipe.

Example four

After further research, the inventor finds that, in the process of using the balloon catheter, the pressure born by the proximal end and the distal end of the balloon is different, the proximal end of the balloon has continuous blood pressure and blood flow scouring, and the actual situation is that the flowing liquid medicine flows to the distal end of the balloon more easily. Based on this, in the fourth embodiment, the distribution of the first micropores on the surface of the outer balloon is in a non-uniform situation, i.e. the number of the distributed first micropores per unit area is not uniform, or the pore size is not uniform, which is done to allow the drug to uniformly diffuse to the vessel wall. In a preferred embodiment, the distribution density of the first micropores at the proximal end of the balloon is higher than that at the distal end of the balloon, and more preferably, the distribution density of the first micropores gradually decreases from the proximal end to the distal end of the balloon, i.e., the first micropores at the proximal end are densely distributed and the first micropores at the distal end are sparsely distributed. In another preferred embodiment, the first micropores at the proximal end of the balloon have a larger pore size than the first micropores at the distal end of the balloon, and more preferably, the pore size of the first micropores decreases from the proximal end to the distal end.

In another preferred embodiment, as shown in fig. 9, the openings of the blocking walls 125 corresponding to the first micropores near the proximal end of the balloon face the proximal end of the balloon, i.e. after the outer balloon 222 is expanded, the blocking walls 125 near the proximal end of the balloon incline toward the proximal end of the balloon, and the openings of the blocking walls 125 corresponding to the remaining first micropores face the center line L (the center line is the transverse central axis) of the balloon, i.e. the remaining blocking walls 125 incline toward the middle of the balloon. These designs can be used to relieve blood pressure and blood flow scouring, reduce the loss of liquid medicine, and further improve the medicine transfer rate. It is also understood that these means can be used either individually or in combination.

It should be understood that the balloon catheter of the present invention is not only suitable for treating blood vessels, but also can be used in any body lumen, such as veins, main abdominal arteries, etc., where isolation, drainage, support, etc., are required. Moreover, the drug is delivered in a liquid form and contacts the target tissue area, greatly reducing delivery losses and improving the efficiency of drug transfer to the target tissue. In addition, it should be understood that the outer balloon or single layer balloon of the present invention has a uniform diameter after expansion, which means that the diameters of both ends of the balloon and the working regions at both ends are the same, in which case the balloon includes an elliptical, cylindrical or spherical shape. In addition, the micropores on the balloon can be perforated in a manner perpendicular to the longitudinal axis of the balloon or in a manner radial to the balloon through a micro-injection needle.

In summary, according to the technical scheme provided by the embodiment of the present invention, the balloon catheter of the present invention is provided with the blocking wall at the first micro-hole of the outer balloon, and the liquid medicine can be buffered by the blocking wall, so that not only is the spraying speed of the liquid medicine reduced, but also the spraying direction of the liquid medicine is changed, stimulation of the liquid flow under high pressure on the blood vessel wall can be effectively blocked, the perfusion of the liquid medicine is completed in a mild manner, and the occurrence of vasospasm is reduced. In addition, the blocking wall is preferably inclined towards the middle of the balloon, so that the liquid medicine is sprayed towards the middle of the balloon, the diffusion direction of the liquid medicine is normalized, the loss of the liquid medicine flowing towards the two ends can be effectively reduced, and the medicine transfer rate is improved. Moreover, the diameter of the expanded outer balloon is uniform, the front end and the rear end of a lesion part do not need to be blocked in the intervention process, the thrombus formed by residual blood is avoided, and the safety of the instrument is improved. Particularly, in order to relieve blood pressure and blood flow scouring, the distribution density of micropores on the outer balloon is dense at the near end and sparse at the far end, or the pore diameter of the micropores is large at the near end and small at the far end, particularly, the opening of the baffle wall close to the near end of the balloon faces to the near end of the balloon, and the rest baffle walls incline towards the middle part of the balloon, so that the loss of liquid medicine is reduced, and the medicine transfer rate is further improved.

It should be understood that the above-described embodiments specifically disclose features of preferred embodiments of the present invention so that those skilled in the art may better understand the present invention. Those skilled in the art will appreciate that the present invention is susceptible to considerable modification based on the disclosure herein, to achieve the same objects and/or achieve the same advantages as the disclosed embodiments of the present invention. Those skilled in the art should also realize that such similar constructions do not depart from the scope of the present disclosure, and that they may make various changes, substitutions and alterations herein without departing from the scope of the present disclosure.

Claims

1. A balloon catheter comprises a catheter body and a balloon, wherein the balloon is sleeved on the catheter body, and the balloon catheter is characterized by at least comprising a first balloon, a plurality of first micropores are formed in the first balloon, and blocking walls are arranged at the first micropores; after the saccule is expanded, the blocking wall inclines towards the corresponding first micropore to at least partially cover the first micropore, a liquid medicine channel is reserved between the blocking wall and the corresponding first micropore, and the extending direction of the liquid medicine channel is not perpendicular to the longitudinal axis of the saccule conduit.

2. A balloon catheter according to claim 1, wherein the first micropores are distributed at a higher density at the proximal end of the balloon than at the distal end of the balloon; and/or the first micropores at the proximal end of the balloon have a larger pore size than the first micropores at the distal end of the balloon.

3. The balloon catheter of claim 1 wherein, when the balloon is expanded, the wall adjacent the proximal end of the balloon is sloped toward the proximal end of the balloon and the remaining wall is sloped toward the middle of the balloon.

4. A balloon catheter according to claim 1 or 2, wherein all the retaining walls are inclined towards the middle of the balloon when the balloon is expanded.

5. The balloon catheter according to any one of claims 1 to 3, wherein the barrier wall is configured to be variable in position relative to the first micro-hole to adjust an extending direction of the liquid medicine passage.

6. The balloon catheter according to claim 5, wherein the barrier wall extends outwardly from the wall of the corresponding first micro-hole.

7. A balloon catheter according to any of claims 1-3, wherein said balloon further comprises a second balloon nested within said first balloon; the second balloon is provided with a plurality of second micropores; the catheter body having an inflation lumen;

8. The balloon catheter of claim 7, wherein a number of the second micro-holes are staggered from a number of the first micro-holes in a balloon-transverse direction.

9. The balloon catheter according to claim 7, wherein the second micropores have a pore size ranging from 5.0 μm to 500 μm, and the first micropores have a pore size ranging from 5.0 μm to 800 μm.

10. A balloon catheter according to any of claims 1-3, wherein said balloon further comprises a second balloon nested within said first balloon; the catheter body is provided with a filling cavity and a drug delivery cavity which are isolated from each other;

11. A method of making a balloon catheter, comprising:

12. The method for preparing a balloon catheter according to claim 11, wherein when the balloon is provided with micropores, the distribution density of the micropores at the balloon proximal end is higher than that of the micropores at the balloon distal end, and/or the pore diameter of the micropores at the balloon proximal end is larger than that of the micropores at the balloon distal end.

13. The method of claim 11 or 12, wherein after the balloon is expanded, the wall near the proximal end of the balloon is inclined toward the proximal end of the balloon, and the remaining wall is inclined toward the middle of the balloon.

14. A method for manufacturing a balloon catheter according to claim 11 or 12, wherein all the blocking walls are inclined toward the middle of the balloon when the balloon is expanded.

15. The method of manufacturing a balloon catheter according to claim 11, wherein the balloon maintains a uniform diameter after expansion.