CN110575606A - drug-eluting balloon dilatation catheter and use method thereof - Google Patents

Abstract

the embodiment of the invention discloses a drug eluting balloon dilatation catheter, which comprises a double-lumen catheter and a double-lumen catheter seat connected with one end of the double-lumen catheter, wherein the other end of the double-lumen catheter is connected with a drug balloon with a drug coating on the surface, the double-lumen catheter seat is communicated with the drug balloon through the double-lumen catheter, a protective sleeve which can move relative to the double-lumen catheter and the drug balloon and is used for restraining the drug balloon is sleeved outside the drug balloon, the device is provided with the protective sleeve, when the balloon is inserted into a blood vessel, the balloon is not directly washed by blood because the protective sleeve is sleeved on the surface of the balloon, and when the balloon with drugs extends into a diseased blood vessel of a patient, the balloon is exposed from the protective sleeve and is filled to be closely attached to the diseased vessel, so that the treatment operation is carried out, and the operation process is simple and convenient, and the condition that the drug amount is lost due to the friction of the inner wall of the blood vessel on the surface of the balloon is avoided.

Description

drug-eluting balloon dilatation catheter and use method thereof

Technical Field

The embodiment of the invention relates to the technical field of medical instruments, in particular to a drug eluting balloon dilatation catheter and a using method thereof.

Background

the balloon dilating catheter is a soft catheter with an inflatable balloon at the head end, and the main structure of the current balloon dilating catheter comprises a balloon, a catheter and a double-cavity catheter holder, which are commonly used for dilating narrow hollow organs in a human body under the guidance of images, such as blood vessels, digestive tracts, urinary tracts and the like. The balloon and the catheter enter a diseased blood vessel under the condition of no expansion, the catheter can be quickly inflated when the balloon is sent to the diseased blood vessel, so that the medicine coating on the surface of the balloon is tightly attached to the inner wall of the diseased region of the blood vessel, and the balloon can be retracted after the treatment is successful so as to withdraw the balloon catheter to the outside of the body.

when using, need to send the sacculus to vascular pathological change blood vessel, and after the sacculus was inserted blood vessel, thereby blood in the blood vessel can circulate incessantly erode the medicine coating on sacculus surface, when the coating sacculus reachs pathological change blood vessel, the dose on the sacculus will run off in a large number, lead to treatment effect to descend, in order to solve this problem, for example application number 201721443136.5, the patent name is a medicine sacculus expansion pipe's utility model patent, it is main exactly through setting up the medicine coating thickness on sacculus surface to be from the sacculus to be close to the one end of two-chamber pipe seat and be the trend distribution that the linearity increases gradually to the other end, nevertheless when the operation, the friction of blood vessel inner wall can't be avoided, if the pipe length that stretches into is longer, the loss degree of medicine on the sacculus also can be bigger partially, lead to treatment effect to descend.

Disclosure of Invention

Therefore, the embodiment of the invention provides a drug eluting balloon dilatation catheter and a using method thereof, and aims to solve the problem that in the prior art, after a balloon is inserted into a blood vessel, blood in the blood vessel and the inner wall of the blood vessel both wash and rub a drug coating, so that a large amount of drug on the balloon is lost, and the treatment effect is reduced.

In order to achieve the above object, an embodiment of the present invention provides the following:

in a first aspect of an embodiment of the present invention, a drug eluting balloon dilatation catheter is provided, including a dual-lumen catheter and a dual-lumen catheter holder connected to one end of the dual-lumen catheter, wherein the other end of the dual-lumen catheter is connected to a drug balloon having a drug coating on a surface thereof, the dual-lumen catheter holder is communicated with the drug balloon through the dual-lumen catheter, a protective sleeve which can move relative to the dual-lumen catheter and the drug balloon and is used for restraining the drug balloon is sleeved outside the drug balloon, and when the protective sleeve is moved away from the drug balloon onto the dual-lumen catheter, the drug balloon is inflated and dilated through the dual-lumen catheter, so that the drug coating on the outer surface of the drug balloon is fully contacted with a diseased blood vessel of a human body.

as a preferable scheme of the invention, the double-lumen catheter comprises an inner tube and an outer tube sleeved on the inner tube, the drug balloon is communicated with the inside of the outer tube, the inner tube penetrates through the drug balloon to the outside and is connected with a flexible tip, the drug balloon, the inner tube and the outer tube are sealed, one end of the flexible tip, which is far away from the drug balloon, is set as a flexible tip, the other end of the flexible tip is set as a flexible connecting part, and the flexible connecting part is butted with the end part of the protective sleeve.

As a preferable aspect of the present invention, the flexible tip is a tubular structure sleeved at the end of the inner tube, a protruding portion extending outward along the tube wall is disposed on the outer side of the flexible tip, and an outer diameter of the protruding portion is larger than an outer diameter of an end of the protective sleeve abutting against the flexible connecting portion.

In a preferred embodiment of the present invention, the outer surface of the protective sleeve is provided with a lubricating coating, the lubricating coating is a hydrophobic coating or a hydrophilic coating, and the inner surface of the protective sleeve is provided with a polytetrafluoroethylene coating.

as a preferable scheme of the invention, a reinforced pipe is arranged on the inner wall of one end of the protective sleeve close to the double-cavity catheter seat, and the reinforced pipe is in contact with the outer wall of the double-cavity catheter; the protective sleeve is provided with a fixing ring close to the outer wall of the end part of the double-cavity catheter holder.

As a preferable scheme of the invention, the double-cavity catheter holder comprises a tube holder body, and a guide wire channel and a transfusion channel which are arranged on the tube holder body, wherein the guide wire channel is communicated with the inner tube, and the direction of the guide wire channel is the same as that of the inner tube; the infusion channel is communicated with the outer pipe, and the infusion channel and the outer pipe are obliquely arranged in the pipeline direction.

As a preferred scheme of the invention, the flexible end is made of any one material or a mixture of materials of polyethylene, polypropylene, polyether amide or nylon.

As a preferable aspect of the present invention, the tube structure of the protective sleeve may be a single-lumen tube, a braided tube, a single-layer tube, a multi-layer tube, a reducer tube, or a multi-structure hybrid tube; and the protective sleeve can be made of polytetrafluoroethylene, polyolefin, polyamide, polyether amide and polyester or a mixture of any two or more of the above materials.

In a preferred embodiment of the present invention, the reinforcing tube is made of a polymer material or a metal material.

in a second aspect of an embodiment of the present invention, there is provided a method of using a drug eluting balloon dilation catheter, comprising the steps of:

Step 100, spraying a medicine on the surface of the balloon to form a medicine coating;

Step 200, inserting a long mandrel from an inner tube of a double-cavity catheter;

And 300, arranging a movable protective sleeve on the outer tube, arranging a flexible end head for guiding and extending into a human pathological change blood vessel at the end part of the inner tube, butting the flexible end head with the protective sleeve, contracting the saccule in the protective sleeve, and pulling out the long mandrel.

Step 400, when the medicine balloon reaches a human pathological change blood vessel, keeping the double-cavity catheter still, gradually pulling the protective sleeve outwards to enable the medicine balloon to be completely exposed, and fully expanding the medicine balloon through the outer tube so that the medicine coating on the outer surface of the medicine balloon can fully contact the human pathological change blood vessel.

The embodiment of the invention has the following advantages:

this equipment is equipped with protective case, when the sacculus inserts blood vessel, protective case has been cup jointed because of the sacculus surface, so the sacculus can directly not receive the washing of blood in the blood vessel, and when the sacculus that has the medicine stretches into patient's vascular pathological change blood vessel, it exposes and makes it be sufficient to hug closely the pathological change blood vessel from protective case again, thereby treat the operation, its operation process is simple and convenient, and the friction of blood vessel inner wall to sacculus surface medicine has still been avoided, the condition that leads to the dose loss takes place, protective case's setting still can play the effect of protection blood vessel inner wall simultaneously, make sacculus pipe remove the in-process can not harm the blood vessel.

drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. It should be apparent that the drawings in the following description are merely exemplary, and that other embodiments can be derived from the drawings provided by those of ordinary skill in the art without inventive effort.

The structures, ratios, sizes, and the like shown in the present specification are only used for matching with the contents disclosed in the specification, so as to be understood and read by those skilled in the art, and are not used to limit the conditions that the present invention can be implemented, so that the present invention has no technical significance, and any structural modifications, changes in the ratio relationship, or adjustments of the sizes, without affecting the effects and the achievable by the present invention, should still fall within the range that the technical contents disclosed in the present invention can cover.

FIG. 1 is a schematic overall structure diagram of an embodiment of the present invention;

FIG. 2 is a schematic view of a flexible link covering a protective sleeve according to an embodiment of the invention;

fig. 3 is a schematic view of a protective sleeve covering a flexible connection according to an embodiment of the invention;

FIG. 4 is a schematic illustration of a planar interface of a flexible link with a protective sleeve according to an embodiment of the invention;

Fig. 5 is a front cross-sectional view of a protective sleeve of an embodiment of the present invention;

FIG. 6 is a schematic diagram of a flexible tip configuration according to an embodiment of the present invention.

In the figure:

1-a double lumen catheter; 2-a dual lumen catheter hub; 3-a drug balloon; 4-protecting the sleeve; 5-a flexible end;

101-an inner tube; 102-an outer tube;

201-pipe seat body; 202-a guide wire channel; 203-an infusion channel;

401 — a lubricious coating; 402-polytetrafluoroethylene coating; 403-a reinforced pipe; 404-a fixed ring;

501-a flexible tip; 502-a flexible connection; 503-a projection.

Detailed Description

The present invention is described in terms of particular embodiments, other advantages and features of the invention will become apparent to those skilled in the art from the following disclosure, and it is to be understood that the described embodiments are merely exemplary of the invention and that it is not intended to limit the invention to the particular embodiments disclosed. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

As shown in fig. 1, the invention provides a drug-eluting balloon dilatation catheter, which avoids the washing of blood in blood vessels on the surface of a balloon through a protective sleeve 4 sleeved on the surface of the balloon, thereby reducing the dosage loss of a drug coating when the drug coating reaches a diseased blood vessel and ensuring that the subsequent treatment effect is not influenced.

Comprises a double-cavity catheter 1 and a double-cavity catheter seat 2 connected with one end of the double-cavity catheter 1, the other end of the double-cavity catheter 1 is connected with a drug balloon 3 with a drug coating on the surface, the drug coating is the effective length part of the drug balloon 3, and the drug coating can be paclitaxel, paclitaxel derivatives, rapamycin and rapamycin derivatives, the doctor can paint the drug coating according to the requirement, the double-cavity catheter seat 2 is communicated with the drug balloon 3 through the double-cavity catheter 1, the outer side of the drug saccule 3 is sleeved with a drug saccule 3 which can move relative to the double-cavity catheter 1 and the drug saccule 3, and is used for restraining the protective sleeve 4 of the drug balloon 3, when the protective sleeve 4 is moved away from the drug balloon 3 to the double-cavity catheter 1, the drug balloon 3 is inflated and expanded through the double-cavity catheter 1, so that the drug coating on the outer surface of the drug balloon 3 is fully contacted with a human pathological change blood vessel.

The double-cavity catheter seat 2 comprises a catheter seat body 201, and a guide wire channel 202 and a transfusion channel 203 which are arranged on the catheter seat body 201, wherein the guide wire channel 202 is communicated with the inner tube 101, and the pipeline directions of the guide wire channel 202 and the inner tube 101 are the same; the infusion channel 203 is communicated with the outer tube 102, the infusion channel 203 and the outer tube 102 are obliquely arranged in the pipeline direction, one end of the medicine balloon 3 is hermetically connected with the inner tube 101, and the other end of the medicine balloon 3 is hermetically connected with the outer tube 102, so that medicine injected into the outer tube 102 can completely enter the medicine balloon 3 and is expanded to be tightly attached to a blood vessel with pathological changes.

The double-lumen catheter 1 comprises an inner tube 101 and an outer tube 102 sleeved on the inner tube 101, the drug balloon 3 is communicated with the inside of the outer tube 102, the inner tube 101 penetrates through the drug balloon 3 to be externally connected with a flexible end head 5, the flexible end head 5 can be a flexible end head commonly seen in the market, meanwhile, the flexible end head 5 is related to the capability of the drug balloon 3 to pass through a vascular occlusion lesion, namely, the flexible end head 5 can assist the drug balloon 3 to pass through the vascular occlusion lesion, wherein the flexible tip 501 can pass through a severely stenotic lesion of a blood vessel, and the flexible connecting part 502 can adjust the capability of the flexible tip 101 to pass through a stenotic lesion blood vessel through different connecting modes with the protective sleeve 4.

When the balloon dilatation catheter is used, a medicine coating can be formed by spraying medicine on the surface of a medicine balloon 3, then a long mandrel is inserted into an inner tube of a double-cavity catheter 1, the strength of the whole double-cavity catheter 1 is enhanced, a movable protective sleeve 4 is conveniently arranged on an outer tube 102, a flexible end head 5 used for guiding the medicine balloon to stretch into a human body pathological change blood vessel is arranged at the end part of the inner tube 101, the flexible end head 5 is butted with the protective sleeve 4, the medicine balloon 3 is folded and contracted in the protective sleeve 4, and the flexible end head 5 mainly plays a role in guiding the whole device to stretch into the human body pathological change blood vessel;

After the long mandrel is pulled out, the flexible end 5 is gradually stretched into a human body, when the medicine balloon 3 reaches a blood vessel with human vascular pathological changes, the double-cavity catheter 1 is kept still, the protective sleeve 4 is gradually pulled outwards, so that the medicine balloon 3 is completely exposed, and the medicine balloon is fully expanded through the outer tube, so that a medicine coating on the outer surface of the medicine balloon fully contacts the blood vessel with human vascular pathological changes.

In the present embodiment, the outer tube of the double-lumen catheter 1 is communicated with the inside of the drug balloon 3, and the balloon catheter 3 is inflated in such a manner that a liquid is injected into the outer tube, which generally requires that the drug balloon 3 has no permeability, and the injected liquid is a liquid that does not clinically affect the human body.

In addition, in the embodiment, a plurality of nano micropores can be uniformly arranged on the drug balloon 3, so that liquid can slowly permeate through the drug balloon; with the drug balloon 3 having such a structure, the diseased blood vessel can be coated with the drug in the following two cases:

In the first case, the drug balloon 3 does not have a drug coating, so that the trouble of preparing the drug coating can be omitted, and when the drug balloon 3 is completely exposed in a diseased blood vessel, the drug solution is injected into the drug balloon through the outer tube, but the drug solution is more lost in the case;

In the second case, a drug coating is provided on the drug balloon 3, and a drug solution is also injected into the drug balloon through the outer tube, and a small amount of drug solution may be injected at this time as a supplementary effect.

in this embodiment, a seal is required between the drug balloon 3 and the inner tube 101 and the outer tube 102 to prevent the liquid for filling the drug balloon 3 from entering the human body.

the flexible end head 5 is a tubular structure sleeved at the end part of the inner tube 101, a protruding part 503 extending outwards along the tube wall is arranged on the outer side of the flexible end head 5, the outer diameter of the protruding part 503 is larger than the outer diameter of the end, butted with the flexible connecting part 502, of the protective sleeve 4, and the flexible end head 5 is made of any one material or a mixture of materials of polyethylene, polypropylene, polyether amide and nylon; when the balloon dilatation catheter is used for extending into a human body, the flexible tip 501 firstly enters the human body, then other parts are guided to gradually enter the human body, and in the process that the flexible tip 501 gradually moves, the bulge part 503 can expand the part passing through the human body, so that the outer wall of the protection sleeve 4 can pass through more easily.

The connection modes between the flexible connecting portion 502 and the protective sleeve 4 are divided into three types:

Firstly, as shown in fig. 4, the end of the flexible connecting part 502 is in plane butt joint with the protective sleeve 4, and the conventional connecting mode is simple and convenient;

Secondly, as shown in fig. 3, the end of the protection sleeve 4 is turned outwards to form a hollow truncated cone section with a larger radius than the protection sleeve 4, the end of the flexible connecting part 502 is connected between the hollow truncated cone section and the outer wall of the inner tube 101, and the connection between the protection sleeve 4 and the flexible connecting part 502 is tighter;

Thirdly, as shown in fig. 2, a certain gap is left between the end of the flexible connection portion 502 and the outer wall of the inner tube 101, and the end of the protection sleeve 4 is connected in the gap, so that not only the connection between the protection sleeve 4 and the flexible connection portion 502 is tighter, but also the radius of the flexible tip 501 of the flexible tip 5 is relatively smaller, and the flexible tip is more suitable for being guided into a narrower diseased blood vessel.

as shown in fig. 1 and 3, the outer surface of the protection sleeve 4 is provided with a lubricating coating 401, the lubricating coating 401 is a hydrophobic coating or a hydrophilic coating, the lubricating coating 401 can be coated with a hydrophobic coating and a hydrophilic coating, so that the protective sleeve 4 can safely slide when passing through a diseased blood vessel, i.e., the degree of lubrication between the protective sleeve 4 and the blood vessel, is increased, thereby reducing the degree of damage to the blood vessel, and the inner surface of the protective sleeve 4 is provided with a teflon coating 402, the polytetrafluoroethylene coating 402 has the characteristics of acid and alkali resistance and resistance to various organic solvents, is almost insoluble in all solvents, meanwhile, the polytetrafluoroethylene has the characteristic of high temperature resistance, the friction coefficient of the polytetrafluoroethylene is extremely low, the protective sleeve 4 and the medicine balloon 3 can safely slide relatively, and the medicine balloon 3 cannot be pulled to influence the medicine balloon 3.

The pipe structure of the protective sleeve 4 can be a single-cavity pipe, a braided pipe, a single-layer pipe, a multi-layer pipe, a reducer pipe or a multi-structure mixed pipe; the protective sleeve 4 can be made of polytetrafluoroethylene, polyolefin, polyamide, polyether amide and polyester or any two or more of the above materials in a mixed mode, so that the protective sleeve 4 and the drug balloon 3 can normally slide, the situation that the drug balloon 3 is bent due to the fact that the protective sleeve 4 is moved is avoided, meanwhile, the protective sleeve 4 is made of multiple tubular structures and materials, the protective sleeve 4 is wide in application range, and selection can be conducted according to economic capacity and the position of pathological changes.

A reinforced pipe 403 is arranged on the inner wall of one end of the protective sleeve 4 close to the double-cavity catheter holder 2, and the reinforced pipe 403 is in contact with the outer wall of the double-cavity catheter 1; the outer wall of the end part of the protective sleeve 4 close to the double-cavity catheter seat 2 is provided with a fixing ring 404, the fixing ring 404 is in a ring buckle shape, when the medicine balloon 3 is delivered to a blood vessel with vascular lesion, a user only needs to withdraw the fixing ring 404, and then the reinforcing tube 302 can drive the protective sleeve 4 to move, so that the medicine balloon 3 can be normally exposed.

the reinforced tube 403 is made of polymer or metal, and may be a polyamide, a nickel titanium tube or a stainless steel tube, so that when a user applies a force to the reinforced tube 403, the reinforced tube 403 is not deformed, which may cause the double-lumen catheter 1 to be bent.

After the drug balloon 3 extends into a blood vessel with pathological changes, the fixing ring 404 can be directly pulled, so that the reinforcing tube 403 can carry the protective sleeve 4 to move backwards until the drug balloon 3 is completely exposed, and then the drug balloon 3 can be dilated by inputting drug liquid through the outer tube 102 to be fully contacted with the pathological blood vessel.

In this embodiment, in order to make the therapeutic effect of the drug balloon better, the thickness of the center of the drug coating is made smaller than the thickness of the two ends, so that the drug can be more uniformly contacted with the diseased blood vessel when the device is used, because when the drug coating just contacts the diseased blood vessel, blood can impact the drug coating near one end of the flexible tip 501, so that the drug coating is rapidly dissolved, and the amount of the drug contacted with the region is reduced, and the drug coating is set to be thick at the two ends and thin in the middle, so that even if one end of the drug coating is dissolved when contacting blood, the other end of the drug coating can also play a certain blocking role, and the partially dissolved drug is blocked in the middle region, thereby avoiding the loss of a large amount of the drug, and making the amount of the drug contacted with the diseased blood vessel more and.

Although the invention has been described in detail above with reference to a general description and specific examples, it will be apparent to one skilled in the art that modifications or improvements may be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.

Claims (10)

1. A drug-eluting balloon dilatation catheter, which comprises a double-cavity catheter (1) and a double-cavity catheter seat (2) connected with one end of the double-cavity catheter (1), it is characterized in that the other end of the double-cavity catheter (1) is connected with a drug balloon (3) with a drug coating on the surface, the double-cavity catheter seat (2) is communicated with the drug balloon (3) through the double-cavity catheter (1), the outer side of the drug balloon (3) is sleeved with a drug balloon (3) which can move relative to the double-cavity catheter (1) and the drug balloon (3), and a protective sleeve (4) for restraining the drug balloon (3), wherein when the protective sleeve (4) is moved away from the drug balloon (3) onto the double-lumen catheter (1), the drug balloon (3) is inflated and expanded through the double-cavity catheter (1), so that the drug coating on the outer surface of the drug balloon (3) is fully contacted with the lesion blood vessel of the human body.

2. The drug elution balloon dilatation catheter according to claim 1, characterized in that the double-lumen catheter (1) comprises an inner tube (101) and an outer tube (102) sleeved on the inner tube (101), the drug balloon (3) is communicated with the inside of the outer tube (102), the inner tube (101) passes through the drug balloon (3) to be connected with a flexible tip (5) to the outside, the drug balloon (3) is sealed with the inner tube (101) and the outer tube (102), one end of the flexible tip (5) far away from the drug balloon (3) is provided with a flexible tip (501), the other end of the flexible tip (5) is provided with a flexible connecting part (502), and the flexible connecting part (502) is butted with the end of the protection sleeve (4).

3. the drug-eluting balloon dilatation catheter according to claim 2, wherein the flexible tip (5) is a tubular structure sleeved on the end of the inner tube (101), and a protrusion (503) extending outwards along the tube wall is arranged on the outer side of the flexible tip (5), and the outer diameter of the protrusion (503) is larger than the outer diameter of the end of the protection sleeve (4) butted with the flexible connection part (502).

4. A drug eluting balloon dilatation catheter according to claim 2, wherein the outer surface of the protective sleeve (4) is provided with a lubricious coating (401), the lubricious coating (401) is a hydrophobic or hydrophilic coating and the inner surface of the protective sleeve (4) is provided with a teflon coating (402).

5. A drug eluting balloon dilatation catheter according to claim 1 characterized in that the inner wall of the one end of the protective sleeve (4) near the double lumen catheter hub (2) is provided with a reinforcement tube (403), the reinforcement tube (403) is in contact with the outer wall of the double lumen catheter (1); the protective sleeve (4) is provided with a fixing ring (404) close to the outer wall of the end part of the double-cavity catheter seat (2).

6. the drug eluting balloon dilatation catheter according to claim 1, wherein the dual lumen catheter hub (2) comprises a catheter body (201), a guide wire channel (202) and a transfusion channel (203) arranged on the catheter body (201), wherein the guide wire channel (202) is communicated with the inner tube (101), and the guide wire channel (202) is in the same direction as the pipeline of the inner tube (101); the liquid feeding channel (203) is communicated with the outer tube (102), and the liquid feeding channel (203) and the pipeline direction of the outer tube (102) are obliquely arranged.

7. The drug-eluting balloon dilatation catheter according to claim 1, wherein the flexible tip (5) is made of any one or a mixture of polyethylene, polypropylene, polyether amide or nylon.

8. A drug eluting balloon dilatation catheter according to claim 1 wherein the protective sleeve (4) tubing structure is a single lumen tube, a braided tube, a single layer tube, a multi-layer tube, a reducer tube or a multi-structure hybrid tube; and the protective sleeve (4) can be made of polytetrafluoroethylene, polyolefin, polyamide, polyether amide and polyester or a mixture of any two or more of the above materials.

9. The drug-eluting balloon dilation catheter according to claim 5, wherein the reinforcing tube (403) is a polymer material or a metal material.

10. A method of using a drug eluting balloon dilation catheter, comprising the steps of:

Step 100, spraying a medicine on the surface of the balloon to form a medicine coating;

Step 200, inserting a long mandrel from an inner tube of a double-cavity catheter;

And 300, arranging a movable protective sleeve on the outer tube, arranging a flexible end head for guiding and extending into a human pathological change blood vessel at the end part of the inner tube, butting the flexible end head with the protective sleeve, contracting the saccule in the protective sleeve, and pulling out the long mandrel.

Step 400, when the medicine balloon reaches a human pathological change blood vessel, keeping the double-cavity catheter still, gradually pulling the protective sleeve outwards to enable the medicine balloon to be completely exposed, and fully expanding the medicine balloon through the outer tube so that the medicine coating on the outer surface of the medicine balloon can fully contact the human pathological change blood vessel.