CN113546281A

CN113546281A - Balloon catheter

Info

Publication number: CN113546281A
Application number: CN202010328663.1A
Authority: CN
Inventors: 王钰富; 李猛; 李俊菲
Original assignee: Shanghai Microport Medical Group Co Ltd
Current assignee: Minimally invasive Investment Holdings Ltd.
Priority date: 2020-04-23
Filing date: 2020-04-23
Publication date: 2021-10-26

Abstract

The invention relates to a balloon catheter, which can suck back liquid medicine outside the balloon catheter through a liquid return channel so as to ensure that a target area to be blocked always keeps higher medicine concentration, thereby reducing the loss of medicine in the processes of conveying and perfusion, improving the efficiency of transferring the medicine to a target tissue and reducing the risk of generating thrombus.

Description

Balloon catheter

Technical Field

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

Background

The coronary heart disease seriously affects the health of human beings, and in 6 months in 2017, data published in 'Chinese cardiovascular disease report 2016' show that the prevalence rate and death rate of cardiovascular diseases in China are still in an ascending stage at present, the coronary heart disease is calculated to be more than 1100 thousands, and a drug eluting stent is a preferred mode for treating the coronary heart disease and is widely applied. But there is increasing evidence that comprehensive evaluation of drug balloons may show advantages in some cases. The drug balloon is a new interventional therapy technology. The medicine balloon attaches the medicine for inhibiting cell proliferation on the surface of the balloon, and the medicine is delivered into the local vascular wall of pathological changes by expanding the balloon so as to achieve the effect of inhibiting smooth muscle proliferation.

In clinical application, the balloon is expanded at a narrow part and kept for a certain time, and the medicine coated on the surface of the balloon is contacted with the blood vessel wall so as to transfer the medicine to the blood vessel wall to play the therapeutic effect of the medicine. The use of a drug balloon typically expands for 30 to 60 seconds and the entire delivery is completed within 25 minutes. Drug balloons present therapeutic challenges due to the very short contact time between the drug on the balloon surface and the vessel wall, and limited transfer and utilization of the drug. The delivery and expansion of the balloon are accompanied by a great loss of the medicine: the drug loss during the vascular delivery of the balloon is about 10% to 25%, the actual transfer to the target tissue is about 1% to 10%, the distal circulation after balloon inflation is 60% to 70%, and the drug remaining on the balloon after inflation is 10% to 20%.

Therefore, how to reduce the mass loss of the drug during the delivery process and improve the efficiency of transferring the drug to the tissue is a further problem to be solved by the drug balloon.

Disclosure of Invention

The invention aims to provide a balloon catheter, which aims to solve the problems that a large amount of medicines are lost in the conveying process, the medicine transfer efficiency is low and the like in the conventional medicine coating balloon.

In order to achieve the above object, according to one aspect of the present invention, there is provided a balloon catheter, including a catheter body and balloons, wherein the balloons include a first balloon, a second balloon and a third balloon, and the first balloon, the second balloon and the third balloon are sequentially sleeved on the catheter body at intervals along an axial direction of the catheter body from a proximal end and a distal end;

the expanded diameters of the first balloon and the third balloon are both larger than the expanded diameter of the second balloon; the conduit body at least comprises a liquid inlet channel and a liquid return channel which are separated from each other; the liquid inlet channel is used for conveying liquid to the second balloon, and the surface of the second balloon is provided with a plurality of micropores for releasing the liquid; the distal end of the liquid return channel is provided with at least one suction port, and liquid on the periphery of the second balloon is withdrawn through the at least one suction port.

Optionally, at least one of the suction ports is located between the first balloon and the second balloon.

Optionally, the catheter body further comprises an filling channel, which is isolated from the liquid inlet channel and the liquid return channel respectively;

the inflation channel has at least one inflation port in communication with the first balloon for delivering an inflation medium through the inflation channel to the first balloon to inflate the first balloon;

the liquid inlet channel is provided with at least two liquid inlets which are respectively communicated with the second balloon and the third balloon so as to convey liquid to the second balloon and the third balloon through the liquid inlet channel to enable the second balloon and the third balloon to be inflated.

Optionally, the catheter body comprises an outer tube and an inner tube; the outer tube comprises first, second and third axially extending lumens, the first lumen being configured as the flashback passage, the third lumen being configured as the filling passage, and the inner tube being configured as the insufflation passage;

the inner tube is inserted into the second lumen and extends beyond a distal end of the second lumen; the second balloon and the third balloon are sleeved at the distal end of the inner tube; the first balloon is sleeved on the outer tube.

Optionally, the catheter body comprises an outer tube, an inner tube, and a suction catheter; the outer tube comprises first, second and third axially extending lumens, the third lumen being configured as the filling channel, the inner tube being configured as the feed channel, the suction catheter being configured as the return channel;

the suction catheter is inserted into the first lumen and extends out of the distal end of the first lumen; the inner tube is inserted into the second lumen and extends out of the distal end of the second lumen; the second balloon and the third balloon are sleeved at the distal end of the inner tube; the first balloon is sleeved on the outer tube.

Optionally, the liquid inlet channel has at least three liquid inlets, and the liquid inlets are respectively communicated with the first balloon, the second balloon and the third balloon, so as to deliver liquid medicine to the first balloon, the second balloon and the third balloon through the liquid inlet channel, so as to inflate the first balloon, the second balloon and the third balloon.

Optionally, the catheter body comprises an outer tube and an inner tube, the outer tube comprising first and second axially extending lumens, the first lumen configured as the flashback passage, the inner tube configured as the insufflation passage;

the inner tube is inserted into the second lumen and extends out of the distal end of the second lumen; the second balloon and the third balloon are sleeved at the distal end of the inner tube; the first balloon is sleeved on the outer tube.

Optionally, the catheter body comprises an outer tube, an inner tube, and a suction catheter; the outer tube comprises first and second axially extending lumens, the suction catheter is configured as the flashback passage, and the inner tube is configured as the intake passage;

Optionally, the second balloon is a single layer balloon or a double layer balloon; when the second sacculus is double-deck sacculus, the micropore has been seted up on the outer sacculus of double-deck sacculus on the surface, perhaps, a plurality of micropores have all been seted up on the surface of the outer sacculus of double-deck sacculus and inlayer sacculus.

Optionally, the first balloon has an expanded axial length less than a radial height, and/or the third balloon has an expanded axial length less than a radial height.

Optionally, the first and/or third balloon is a non-compliant balloon.

In order to achieve the above object, according to another aspect of the present invention, there is provided a balloon catheter, including a catheter body and a balloon, wherein the balloon includes a proximal balloon and a distal balloon, and the proximal balloon and the distal balloon are sequentially sleeved on the catheter body at intervals along an axial direction of the catheter body from a proximal end and a distal end;

the conduit body at least comprises a liquid inlet channel and a liquid return channel which are separated from each other; the liquid inlet channel is used for conveying liquid; the surface of the far-end balloon or the liquid inlet channel is provided with a plurality of micropores for releasing the liquid; the distal end of the liquid return channel is provided with at least one suction port, and liquid outside the balloon catheter is withdrawn through the at least one suction port, and the at least one suction port is positioned between the proximal balloon and the distal balloon.

Optionally, when the distal balloon has a plurality of micropores formed on a surface thereof, the distal balloon includes a proximal portion and a distal portion, the expanded diameter of the distal portion is larger than the expanded diameter of the proximal portion, and the micropores are located on the surface of the proximal portion.

Optionally, the proximal balloon has an expanded axial length less than a radial height.

Optionally, when the surface of the liquid inlet channel is provided with a plurality of micropores, the axial length of the inflated distal balloon is smaller than the radial height.

Optionally, the proximal balloon and/or the distal balloon are non-compliant balloons.

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

the balloon catheter is mainly used for delivering medicaments, when in actual use, a target area in a body can be filled through the near-end balloon and the far-end balloon, blood flow can be blocked for a short time, liquid medicaments can conveniently enter the target area (such as blood vessels) through micropores formed in the surface of the far-end balloon or the liquid inlet channel, continuous infusion of the liquid medicaments is realized, in the process of infusing the liquid medicaments, the liquid medicaments in the blocked area can be continuously pumped back through the liquid return channel on the catheter body, meanwhile, new liquid medicaments are continuously delivered to the liquid inlet channel, and the liquid medicaments can continuously overflow from the micropores of the far-end balloon or the liquid inlet channel to the blocked target area. Meanwhile, due to the suction effect of the liquid return channel in the plugging area, the liquid circularly flows, the probability of forming thrombus in the plugging area is reduced, and the safety of the instrument is improved. Moreover, the target area is blocked by the near-end balloon and the far-end balloon, so that the loss of the liquid medicine flowing to the two ends of the balloons is reduced, and the transfer efficiency of the medicine is further improved;

the axial length of the expanded near-end saccule (comprising the first saccule) and/or the expanded far-end saccule (comprising the third saccule) is preferably smaller than the radial height, so that the problem of calcified lesion of the blood vessel can be better solved, because the shape of a calcified lesion part of the blood vessel is usually irregular, the conventional saccule cannot be better attached to the blood vessel wall of the calcified lesion, and the lesion blood vessel cannot be effectively blocked.

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 a schematic structural view of an exemplary balloon catheter of the present invention with the outer tube in cross-section;

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

FIG. 3 is a schematic representation of the use of an exemplary balloon catheter of the present invention;

FIG. 4 is an end view of an exemplary outer tube of the present invention;

FIG. 5 is an enlarged partial view of an exemplary balloon catheter of the present invention;

FIG. 6 is an enlarged partial view of an exemplary balloon catheter of the present invention, wherein the first balloon has a disk shape;

FIG. 7 is a micrograph of microwells provided in an assay of the present invention;

fig. 8 is a graph comparing the immediate tissue drug concentration of a conventional drug coated balloon in the experiments of the invention with a balloon catheter of the invention.

In the figure: a balloon catheter 100; a catheter body 110; an outer tube 110 a; an inner tube 110 b; a suction duct 110 c; a balloon 120; a first balloon 121; a second balloon 122; a third balloon 123; a micro-pore 124; a liquid inlet passage 111; a liquid return passage 112; an inflation channel 113; a suction port 114; a first lumen 115; a second lumen 116; a third lumen 117; the blood vessel S.

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; "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 balloons, wherein the balloons comprise a first balloon, a second balloon and a third balloon, the first balloon, the second balloon and the third balloon are sequentially sleeved on the catheter body at intervals from near to far along the axial direction of the catheter body, and the expanded diameters of the first balloon and the third balloon are larger than the expanded diameter of the second balloon. In addition, the catheter body at least comprises a liquid inlet channel and a liquid return channel which are separated from each other, and the distal end of the liquid return channel is provided with at least one suction port. During practical use, after each sacculus expands in a target area in vivo, because the diameters of the first sacculus and the third sacculus are larger than that of the second sacculus, the target areas can be blocked at two ends of the second sacculus by the first sacculus and the third sacculus, blood flow can be blocked for a short time to pass through, then liquid medicine (containing liquid medicine) can be conveyed to the second sacculus through the liquid inlet channel on the catheter body, and because a plurality of micropores are formed in the surface of the second sacculus, the liquid medicine in the second sacculus can overflow from the micropores to the blocked target area under the pressure action of the liquid medicine, and because of the concentration difference of the medicine, the liquid medicine is transferred to a target tissue through diffusion action and is absorbed by the target tissue. However, as the drug is transferred, the drug concentration in the target tissue increases and the drug concentration difference is also reduced, and at this time, if no measure is taken, the efficiency of diffusion of the drug to the target tissue decreases. Therefore, in the process of injecting the liquid medicine, the liquid medicine on the periphery of the second balloon (namely, the liquid medicine in the target plugging region) needs to be pumped back through the liquid return channel on the catheter body through at least one suction port at the far end of the liquid return channel, so that new liquid medicine can be continuously injected into the target plugging region from the micropores of the second balloon, the liquid medicine in the target plugging region can be always kept at a high concentration, the medicine concentration difference is improved, the liquid medicine is continuously diffused into target tissues, and the medicine transfer efficiency is improved. In particular, due to the suction effect of the liquid return channel, the liquid in the plugging area is driven to circularly flow, so that the risk of forming thrombus by residual blood can be reduced or avoided even if the target area is plugged, and the use safety of the device is improved. It should be understood that the target region herein includes, but is not limited to, a blood vessel. The balloon catheter of the invention is not limited to delivering liquid medicine, and can also deliver other liquid substances in other cases, such as a nano robot. It is also understood that the expanded diameters of the first and third balloons being greater than the expanded diameter of the second balloon include the expanded maximum diameters of the first and third balloons being greater than the expanded maximum diameter of the second balloon.

In the invention, the far end of the liquid return channel is provided with at least one suction port, and the at least one suction port is preferably positioned between the first sacculus and the second sacculus, so that the liquid medicine on the periphery of the second sacculus can be sucked to the liquid return channel through the suction port at the near end in time, the suction efficiency is high, the suction effect is good, the structure of the catheter can be simplified, and the manufacturing cost is low. It is also understood that the second balloon may be a single layer balloon or a double layer balloon. When the second balloon is a double-layer balloon, there are two cases: the first one is that only the surface of the outer saccule is provided with a plurality of micropores, the inner saccule is not provided with any micropores, the inner saccule is nested in the outer saccule, a perfusion cavity is formed between the inner saccule and the outer saccule, at the moment, the whole saccule is expanded through the inner saccule, the liquid medicine is conveyed to the perfusion cavity between the inner saccule and the outer saccule through a liquid inlet channel, and then overflows to a target area through the micropores on the outer saccule; the second is that set up a plurality of micropores on the surface of outer sacculus and inlayer sacculus simultaneously, inlayer sacculus nestification is in outer sacculus, and also forms between inlayer sacculus and the outer sacculus and fill the chamber, at this moment, through the whole sacculus of inlayer sacculus inflation, and the liquid medicine fills the inlayer sacculus earlier, and the micropore on the rethread inlayer sacculus overflows outer sacculus, and further the micropore on the outer sacculus of rethread overflows the target area. Here, it should be understood that the "micro-hole" in the present invention refers to a hole having a size of the order of micrometers, but the shape of the hole is not limited, and the micro-hole is preferably a circular hole in view of convenience of processing.

In the invention, the first balloon, the second balloon and the third balloon are all made of non-compliant or semi-compliant materials, and are not expanded along with the increase of pressure after being expanded to a specified size along with the increase of pressure. And adopt non-compliance or semi-compliance material, prevented that the second sacculus from hindering the medicine absorption after laminating with the vascular wall, can improve the absorptivity of liquid medicine. For example, the material from which the balloon is made may be selected from PEBAX (polyether block polyamide), polyethylene or polyamide, and the like. The second balloon may be an angioplasty balloon or any other balloon used in interventional cardiovascular procedures and is inflated primarily by means of a perfusion solution, while the first and third balloons may be inflated in a percutaneous interventional procedure using conventional means.

In the present invention, the difference between the diameter of the second balloon after inflation and the diameter of the first balloon and the third balloon after inflation is not limited. In the present invention, the shape of the first balloon, the second balloon, and the third balloon after inflation is not limited, and may be spherical, elliptical, cylindrical, or the like, and preferably elliptical. Preferably, the axial length of the first balloon after being inflated is larger than the radial height, and/or the axial length of the third balloon after being inflated is smaller than the radial height, for example, the first balloon and/or the third balloon are disc-shaped, so as to better solve the problem of the calcified vascular lesion.

The number and the distribution mode of the micropores on the second balloon are not particularly required, and the micropores can be uniformly distributed or non-uniformly distributed. In a preferred embodiment, the micropores on the second balloon are uniformly arranged about the longitudinal axis of the second balloon and are disposed in layers along the longitudinal axis. And when the second balloon is a single-layer balloon, the pore diameter of the micropores is preferably in a range of 5.0 to 500 μm, more preferably in a range of 10 to 250 μm, and still more preferably in a range of 10 to 50 μm. Further, when the second balloon is a single-layer balloon, the number of micropores is preferably 5.0 to 100, more preferably 5.0 to 50, and still more preferably 5.0 to 25. It is understood that the pore size and number of pores defined by a single layer balloon are equally applicable to the outer layer balloon in a double layer balloon.

Each balloon in the invention can be prepared by a blow molding process, and the catheter body can be integrally formed or separately formed. The catheter body may be a double, triple or higher lumen tube. In addition, the balloon catheter is not limited to interventional vessels, and can be used for treatment of human body lumens, such as esophagus, bile duct, uterus and accessories thereof, prostate and the like, which need to deliver medicines or other substances.

The balloon catheter of the present invention will now be further described with reference to the accompanying drawings and preferred embodiments thereof, in order to more particularly emphasize the features and characteristics of the above-described embodiments. In the following description, the features and characteristics that can be achieved by the present invention are described assuming that a balloon catheter is used for delivering a medical fluid and for treating cardiovascular diseases, but the present invention should not be construed as being limited thereto.

Fig. 1 is a schematic structural view of a balloon catheter according to a preferred embodiment of the present invention, and fig. 2 is a partially enlarged view of the balloon catheter shown in fig. 1. As shown in fig. 1 to 2, the present embodiment provides a balloon catheter 100, and the balloon catheter 100 specifically includes a catheter body 110 and a balloon 120. The balloon 120 includes a first balloon 121, a second balloon 122, and a third balloon 123. The first balloon 121, the second balloon 122 and the third balloon 123 are sequentially sleeved on the catheter body 110 at intervals from the proximal end to the distal end along the axial direction of the catheter body 110. Wherein, the expanded diameters of the first balloon 121 and the third balloon 123 are larger than the expanded diameter of the second balloon 122. In this embodiment, the second balloon 122 is a single-layer balloon and is provided with a plurality of micropores 124, and the micropores 124 are used for releasing the liquid medicine. The pore diameter of the micropores 124 is 5.0 to 500. mu.m, preferably 10 to 250. mu.m, and more preferably 10 to 50 μm. The number of the micropores 124 is 5.0 to 100, preferably 5.0 to 50, and more preferably 5.0 to 25. Further, the micropores 124 are uniformly arranged about the longitudinal axis of the second balloon 122 and are disposed in several layers along the longitudinal axis.

In this embodiment, the catheter body 110 includes a liquid inlet passage 111, a liquid return passage 112 and a filling passage 113 which are isolated from each other. The liquid inlet channel 111 is used for delivering liquid medicine to the second balloon 122 and the third balloon 123 to inflate the second balloon 122 and the third balloon 123, and after inflation, the liquid medicine is also delivered to the second balloon 122 through the liquid inlet channel 111, and the liquid medicine is forced to overflow from the micropores 124 of the second balloon 122 into the blood vessel by the pressure of the liquid medicine. Specifically, the inlet channel 111 has at least two inlet ports (not shown) respectively communicating with the second balloon 122 and the third balloon 123, so that the inlet channel 111 delivers the liquid medicine to the second balloon 122 and the third balloon 123 through the inlet ports. The inflation channel 113 is used to deliver an inflation medium to the first balloon 121 to inflate the first balloon 121. Specifically, the inflation channel 113 has at least one inflation port (not shown) in communication with the first balloon 121 for delivering the inflation medium to the first balloon 121. The present invention is not limited to the filling medium, which is mainly a liquid, including but not limited to saline, and may also be a contrast medium, etc. The distal ends of the liquid inlet passage 111 and the filling passage 113 are closed, and the distal end of the liquid return passage 112 has at least one suction port 114, and at least one suction port 114 is preferably located between the first balloon 121 and the second balloon 122.

In another preferred embodiment, the third balloon 123 may not be provided, but rather may be provided by providing a protrusion on the distal end of the second balloon 122. In this manner, the balloon 120 includes a first balloon 121 (i.e., a proximal balloon) and a second balloon 122 (i.e., a distal balloon), the second balloon 122 including a proximal portion and a distal portion, the distal portion having an expanded diameter (including a maximum diameter) that is greater than the diameter (including a maximum diameter) of the proximal portion, the micropores being located on a surface of the proximal portion.

In another preferred embodiment, the second balloon 122 may not be provided, instead being perforated directly on the surface of the catheter body 110 for the release of the medical fluid. In this way, the balloon 120 includes a first balloon 121 (i.e., a proximal balloon) and a third balloon 123 (i.e., a distal balloon), and the section of the tube between the first balloon 121 and the third balloon 123 on the liquid inlet channel 111 is provided with micropores.

In another preferred embodiment, the shape of the first balloon 121 and/or the third balloon 123 is specially designed to address the problem of calcified lesions in the blood vessel. As shown in fig. 6, the first balloon 121 has a disk shape after being inflated. In the inflated state of the first balloon 121, the length of the first balloon 121 in the axial direction of the catheter is smaller than the height of the radial projection of the first balloon, preferably twice or more the length of the radial projection of the first balloon. In a more preferred embodiment, the first balloon 121 is a non-compliant balloon and has a maximum expanded diameter equal to or slightly larger than the diameter of the blood vessel, so that free deformation can be realized in the blocked blood vessel, and good blocking effect in the case of calcified lesion of the blood vessel can be realized, and the damage to the blood vessel can be reduced. Similarly, the third balloon 123 may be in the shape of a disk after inflation, not shown. In the inflated state of the third balloon 123, the length of the third balloon 123 in the axial direction of the catheter is smaller than the height of the radial projection of the third balloon 123, preferably twice or more the length. In a more preferred embodiment, the third balloon 123 is also a non-compliant balloon, which not only achieves good occlusion in case of calcified lesions of the blood vessel, but also reduces damage to the blood vessel. It will be appreciated that when the inlet passage is provided with micro-holes or the distal balloon is provided with micro-holes, it is preferred that the axial length of the proximal balloon after inflation is less than its radial height. It should also be understood that when the surface of the inlet channel is provided with micropores, the axial length of the inflated distal balloon is preferably smaller than the radial height thereof.

In the following description, three balloons are mainly used as an example for explanation, but the present invention should not be limited thereto, and those skilled in the art should be able to apply the following description to the case of two balloons.

Fig. 3 is a schematic view of a balloon catheter provided in accordance with a preferred embodiment of the present invention in use. As shown in fig. 3, taking an interventional blood vessel as an example, after the balloon catheter 100 is introduced into the blood vessel S, the three balloons are inflated, wherein the first balloon 121 and the third balloon 123 swell at the proximal end and the distal end of the second balloon 122 to block the blood vessel S for a short time, and block the blood flow, and thereafter, the liquid medicine is delivered into the second balloon 122 through the liquid inlet channel 111, under the action of the liquid medicine pressure, the liquid medicine overflows into the blood vessel S through the micropores 124 on the second balloon 122, and due to the concentration difference of the liquid medicine, the overflowing liquid medicine is diffused and transferred into the blood vessel tissue and absorbed by the blood vessel tissue. In fig. 3, the arrows indicate the flow direction of the chemical solution. And when the liquid medicine is filled, the liquid medicine on the periphery of the second balloon 122 is pumped back through the liquid return channel 112 through the at least one suction port 114 at the far end of the liquid return channel, so that a part of the overflowed liquid medicine is sucked into the liquid return channel 112 (the pumped back liquid medicine is not used any more), and meanwhile, new liquid medicine is continuously conveyed to the second balloon 122 through the liquid inlet channel 111 and overflows from the micropores 124. And because the flow brought by the suction of the suction port 114 also reduces the probability of thrombosis, the safety of the instrument is improved.

The invention is not limited to the type of drug to be delivered, and examples thereof include drugs for inhibiting cell proliferation, anti-inflammatory drugs, antibacterial drugs, antitumor drugs, antimitotic drugs, anti-osteoporosis drugs, anti-angiogenesis drugs, and the like. And may be a combination of multiple drugs. Illustratively, the drug is, for example, one or more of an mTOR inhibitor, paclitaxel and its derivatives, antiplatelet drugs, cilostazol, ticlopidine, triptolide, dexamethasone, methotrexate, fluorouracil, mercaptopurine, hydroxyurea, cytarabine, carboplatin, cisplatin, oxaliplatin, dicycloplatin, daunorubicin, doxorubicin, and arsenic trioxide. The mTOR inhibitor may be one or more combinations of rapamycin (sirolimus), everolimus, ridaforolimus, temsirolimus, and zotarolimus.

In this embodiment, the catheter body 110 can be manufactured separately. In some embodiments, the catheter body 110 may be assembled from an outer tube 110a and an inner tube 110 b. Referring to fig. 1 and 2, the catheter body 110 includes an outer tube 110a and an inner tube 110 b. As shown in fig. 4, the outer tube 110a is a triple lumen tube, and specifically includes a first lumen 115, a second lumen 116, and a third lumen 117 extending axially. The distal end of the first lumen 115 opens to be directly configured as the return fluid passage 112. The distal end of the third lumen 117 is closed and configured to fill the passage 113. In addition, the second inner cavity 116 is used for being installed in the inner tube 110b, and the distal end of the inner tube 110b extends out of the second inner cavity 116, so that the liquid inlet channel 111 is constructed by the inner tube 110 b. In addition, the first balloon 121 is fitted over the outer tube 110a, and the second balloon 122 and the third balloon 123 are fitted over the distal end portion of the inner tube 110b extending out of the outer tube 110 a. In an alternative embodiment, the catheter body 110 may also be integrally formed, such as by machining, to form the outer tube 110a and the inner tube 110 b.

Further, as shown in fig. 5, the catheter body 110 further includes a suction catheter 110c for providing the fluid return passage 112. The suction catheter 110c is inserted into the first lumen 115, and preferably, the distal end of the suction catheter 110c extends out of the first lumen 115 into the blood vessel, so that the medical fluid can be pumped back through the suction catheter 110c through at least one suction port 114 at the distal end thereof, and thus, the suction efficiency is high, and the suction effect is good. In this embodiment, a syringe or a pump may be provided at the proximal end of the suction catheter 110c, and the medical fluid may be withdrawn manually or mechanically through the syringe. It should also be understood that it is not necessary for the distal end of the aspiration catheter 110c to extend out of the first lumen 115 into the blood vessel, and in other instances, the distal end of the aspiration catheter 110c may be concealed within the first lumen 115.

The outer tube 110a may also be a double lumen tube, including a first inner lumen 115 and a second inner lumen 116 extending axially, the first inner lumen 115 being open at a distal end thereof to be directly configured as the fluid return passage 112, and the second inner lumen 116 being configured to receive the inner tube 110b, and a distal end of the inner tube 110b extending out of the second inner lumen 116, so that the fluid inlet passage 111 is directly provided by the inner tube 110b, in which case, the first balloon 121 is disposed on the outer tube 110a, the second balloon 122 and the third balloon 123 are disposed on a distal end portion of the inner tube 110b extending out of the outer tube 110a, and the fluid inlet passage 111 has at least three fluid inlets respectively communicating with the first balloon 121, the second balloon 122 and the third balloon 123, so that the three balloons are inflated by delivering the fluid from the inner tube 110b to the three balloons. Similarly, when the outer tube 110a is a double lumen tube, the fluid return channel 112 may also be provided by the aspiration catheter 110 c.

Further, the catheter body 110 further has a guide wire cavity for passing a guide wire. For example, inner tube 110b provides a guidewire lumen. The proximal end and the distal end of the second balloon 122 are further provided with developing marks so as to judge the position where the liquid medicine needs to be infused according to the developing marks. The development mark is made of a metal development material. In some embodiments, visualization markers are provided adjacent the proximal and distal ends, respectively, of the second balloon 122; in some embodiments, visualization markers are disposed adjacent the distal end of first balloon 121 and visualization markers are disposed adjacent the proximal end of third balloon 123. The development mark may be a development spot or a development ring.

In this embodiment, the number of the suction ports 114 is one, and in other embodiments, the number of the suction ports 114 may be multiple, including 2 or more than 2.

Next, the present embodiment also provides a test result of the drug transfer effect of the existing drug-coated balloon and the balloon catheter of the present invention; wherein, a micro-injection needle is used to perforate in the direction perpendicular to the longitudinal axis of the second balloon 122 to form micropores 124, and the pore diameter of the micropores 124 is 245 μm. As shown in FIG. 7, after the perforation, the pore size of the micropores 124 can be confirmed by a microscope, and FIG. 7 is a micrograph of the micropores 124 having a size of 245 μm. In addition, in the experiment, the experiment was performed using an in vitro animal blood vessel, and the number of specimen duplicate in the experiment was 3.

Specifically, a conventional drug coating balloon is prepared, wherein the drug is a mixture of paclitaxel and iopromide, the mixing mass ratio is 1:1, the mixture is coated on the surface of the balloon by ultrasonic spraying, the diameter of the expanded balloon is 3.0mm, the length of the expanded balloon is 18mm, and the total content of the drug on the sprayed balloon is 508 micrograms. In the balloon catheter, paclitaxel and surfactant tween80 with the same amount are added into water and are uniformly dispersed by probe type ultrasonic oscillation for 180 minutes to serve as perfusion liquid medicine. In the experiment, the drug coating balloon expands for 60 seconds after entering the blood vessel, and 1 ml of liquid medicine is filled in the balloon catheter in 60 seconds after the balloon catheter enters the blood vessel, wherein the content of the filled liquid medicine is 508 micrograms. After inflation or perfusion, the experimental vessel sections were cut and tested for drug tissue concentration, with the results shown in fig. 8. Test results show that after the balloon catheter disclosed by the invention is used, the immediate tissue drug concentration is 2.5 times that of a drug coating balloon, and therefore, the balloon catheter disclosed by the invention has a remarkable drug transfer effect.

In conclusion, according to the technical scheme provided by the embodiment of the invention, the medicine is delivered to the tissue by using the mode of filling the liquid medicine into the balloon, the problem that a large amount of medicine is lost in the delivery process of the traditional medicine coating balloon is solved, the medicine delivery effect is good, and the medicine transfer efficiency is high. Moreover, the blood vessel is blocked by the near-end balloon and the far-end balloon, so that the loss of the liquid medicine flowing to the two ends in the perfusion process is further reduced, and the transfer efficiency of the medicine is further improved. In addition, the liquid medicine is pumped back through the suction catheter, so that the efficiency of transferring the medicine to the tissue is further improved, the risk of thrombus generation in the blocked blood vessel is reduced, and the safety is good. In addition, the near-end saccule and/or the far-end saccule are disc-shaped, so that the problem of vascular calcification lesion is solved well, and the treatment effect is good.

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 is characterized by comprising a catheter body and balloons, wherein the balloons comprise a first balloon, a second balloon and a third balloon, and the first balloon, the second balloon and the third balloon are sequentially sleeved on the catheter body at intervals from a near end and a far end along the axial direction of the catheter body;

2. A balloon catheter according to claim 1, wherein at least one said suction port is located between said first balloon and said second balloon.

3. A balloon catheter according to claim 1 or 2, wherein the catheter body further comprises an inflation channel isolated from the inlet channel and the return channel, respectively;

4. A balloon catheter according to claim 3, wherein the catheter body comprises an outer tube and an inner tube; the outer tube comprises first, second and third axially extending lumens, the first lumen being configured as the flashback passage, the third lumen being configured as the filling passage, and the inner tube being configured as the insufflation passage;

5. A balloon catheter according to claim 3, wherein the catheter body comprises an outer tube, an inner tube and a suction catheter; the outer tube comprises first, second and third axially extending lumens, the third lumen being configured as the filling channel, the inner tube being configured as the feed channel, the suction catheter being configured as the return channel;

6. A balloon catheter according to claim 1 or 2, wherein the inlet channel has at least three inlets communicating with the first, second and third balloons, respectively, for delivering liquid to the first, second and third balloons through the inlet channel to inflate the first, second and third balloons.

7. The balloon catheter of claim 6, wherein the catheter body comprises an outer tube and an inner tube, the outer tube comprising first and second axially extending lumens, the first lumen configured as the flashback passage, the inner tube configured as the intake passage;

8. The balloon catheter of claim 6, wherein the catheter body comprises an outer tube, an inner tube, and a suction catheter; the outer tube comprises first and second axially extending lumens, the suction catheter is configured as the flashback passage, and the inner tube is configured as the intake passage;

9. A balloon catheter according to claim 1 or 2, wherein the second balloon is a single layer balloon or a double layer balloon; when the second sacculus is double-deck sacculus, a plurality of micropores have been seted up on the surface of the outer sacculus of double-deck sacculus, perhaps, a plurality of micropores have all been seted up on the surface of the outer sacculus of double-deck sacculus and inlayer sacculus.

10. A balloon catheter according to claim 1, wherein the first balloon has an expanded axial length less than a radial height and/or the third balloon has an expanded axial length less than a radial height.

11. A balloon catheter according to claim 10, wherein the first and/or third balloon is a non-compliant balloon.

12. The balloon catheter is characterized by comprising a catheter body and balloons, wherein the balloons comprise a near-end balloon and a far-end balloon, and the near-end balloon and the far-end balloon are sequentially sleeved on the catheter body at intervals from the near end to the far end along the axial direction of the catheter body;

13. A balloon catheter according to claim 12, wherein when the distal balloon has a plurality of micropores formed on a surface thereof, the distal balloon includes a proximal portion and a distal portion, the distal portion having an expanded diameter larger than an expanded diameter of the proximal portion, and the micropores are formed on a surface of the proximal portion.

14. The balloon catheter of claim 12, wherein an axial length of the proximal balloon after inflation is less than a radial height.

15. The balloon catheter according to claim 12, wherein when the surface of the liquid inlet channel is provided with a plurality of micropores, the axial length of the inflated distal balloon is smaller than the radial height.

16. A balloon catheter according to claim 12, wherein the proximal balloon and/or the distal balloon is a non-compliant balloon.