CN215129572U

CN215129572U - Shock wave sacculus pipe of little external diameter

Info

Publication number: CN215129572U
Application number: CN202121307155.1U
Authority: CN
Inventors: 郭琪; 邱培
Original assignee: Nanjing Xinke Medical Instrument Co ltd
Current assignee: Nanjing Xinke Medical Instrument Co ltd
Priority date: 2021-06-11
Filing date: 2021-06-11
Publication date: 2021-12-14
Anticipated expiration: 2031-06-11

Abstract

The application relates to a shock wave sacculus conduit with small outer diameter, which comprises an axially extending elongated member, a working capsule body arranged at the distal end part of the elongated member, a transmission lead and an injection pipe, wherein the working capsule body is communicated with the injection pipe in a fluid manner, the proximal end of the transmission lead is electrically connected with an external device, the distal end part of the transmission lead extends into the working capsule body, at least two transmission leads are arranged in the working capsule body, each transmission lead is provided with a non-insulating area, a target electric field can be formed between the non-insulating areas on different transmission leads, a micropore mechanism is also arranged in the working capsule body and wraps the non-insulating areas, the micropore mechanism is an electrically insulating part and is provided with one or more micropores penetrating through the wall of the micropore mechanism, and the micropores can prevent liquid from entering by utilizing the surface tension of the micropore mechanism, so that the microporous means can isolate the non-insulated region from the liquid flowing into the working envelope.

Description

Shock wave sacculus pipe of little external diameter

Technical Field

The application belongs to the field of minimally invasive interventional therapy, and particularly relates to a shock wave balloon catheter with a small outer diameter.

Background

With the aging of the population and the improvement of the living standard, the incidence of vascular diseases increases year by year. The development of vascular conditions causes plaques in the vessel wall to evolve into calcium deposits, thereby narrowing the artery and restricting blood flow. When calcification of blood vessels occurs, the current major conventional practice is to use balloons for dilation, stent implantation or rotational atherectomy balloons to exfoliate plaque. However, these treatments have significant drawbacks, often associated with vascular injury and complications. Such as balloon dilatation and stent implantation, can produce tearing of the intima of the vessel, which often results in hyperplasia of the endothelium of the vessel, creating a risk of restenosis.

To solve this problem, SHOCKWAVE MEDICAL, USA, proposed the use of the electrohydraulic effect lithotripsy technique in angioplasty (patent application No.: 201880040835.6). The basic principle of the method is that a certain electric field is applied to liquid, the liquid generates cavitation under the action of the electric field, bubbles generated by cavitation collapse instantly to generate shock waves, and therefore the purpose of breaking calcified pathological tissues is achieved on the premise that vascular intima is not damaged. However, this method has a problem that an electric field is directly applied to the inside of the liquid, and the electric field intensity required for generating a shock wave of sufficient intensity is high and the current output is large. Once the condition of sacculus damage weeping appears, high voltage heavy current passes through the human body, can cause serious human electric shock accident, endangers patient and medical personnel life safety even. In addition, the existing shock wave balloon catheters are provided with electrode rings to apply an electric field, and the diameter (Profile) of the catheter after a working balloon body is pressed is larger. The pressing and holding diameter (Profile) of the catheter working balloon is a core factor for limiting the passability of the catheter, and the larger diameter (Profile) limits the application field of the catheter in clinic, so that the existing shock wave balloon catheter is difficult to be applied in the fields of coronary artery and the like with smaller vessel diameter and higher requirement on the passability of the catheter. Therefore, there is a need to design a shockwave balloon catheter that is safer and has a smaller maximum outer diameter and superior passability.

Disclosure of Invention

The utility model aims at overcoming current technical defect, design the shock wave sacculus pipe of little external diameter, this shock wave sacculus pipe system reduces the required electric field intensity threshold value of realization liquid cavitation by a wide margin through setting up effectual micropore mechanism, and then realizes producing strong shock wave under the low-voltage weak current condition in order to reduce the risk of product in the use by a wide margin, and reduce the biggest external diameter of sacculus pipe through setting up the uninsulated area, enlarge the range of application of shock wave sacculus pipe.

The purpose of the application is realized by the following technical scheme:

a shock wave sacculus conduit with small outer diameter comprises an axially extending slender member, a working sac body arranged at the far-end part of the slender member, transmission leads arranged in the cavity of the slender member and a liquid injection pipe, wherein the working sac body is communicated with the liquid injection pipe in a fluid mode, the near end of each transmission lead is electrically connected with external equipment, the far-end part of each transmission lead extends into the working sac body, at least two transmission leads are arranged in the working sac body, each transmission lead is provided with a non-insulation area, a target electric field can be formed between the non-insulation areas on different transmission leads, a micropore mechanism is further arranged in the working sac body and wraps the non-insulation areas, the micropore mechanism is an electric insulation part and is provided with one or more micropores penetrating through the wall of the micropore mechanism, the micro-pores can prevent liquid from entering by utilizing the surface tension of the micro-pores, so that the micro-pore mechanism can isolate the non-insulating area from the liquid flowing into the working capsule.

The purpose of the application can be realized by the following technical scheme:

in one embodiment, the non-insulated region is achieved by directly stripping the insulation on the transmission conductor.

In one embodiment, a plurality of pairs of non-insulated regions are provided on two of the transmission conductors to form a plurality of electric fields. Preferably, the plurality of pairs of non-insulating regions are disposed in opposing side-by-side or intersecting relation.

In a preferred embodiment, the plurality of non-insulated regions on each of the transmission conductors are connected in parallel by a connecting conductor.

In a preferred embodiment, the connecting line is of one-piece design with the transmission line.

In one embodiment, an electric field strengthening layer is disposed on the non-insulating region, and the electric field strengthening layer is made of a metal or non-metal material with high conductivity, high stability and low electrode loss.

In a preferred embodiment, the electric field strengthening coating is made of gold, silver, platinum, copper, steel, tungsten, graphene, and corresponding alloys or composites, or a combination thereof. The combination comprises the cooperation of any two structures or the combination of any three structures.

In one embodiment, the surface properties and dimensional structure of the micropores conform to the following quantitative relationship:

wherein P is the absolute pressure of the liquid in the working capsule, delta is the surface tension coefficient, D is the equivalent hydraulic diameter of the pores, and beta is the contact angle of the liquid on the wall surface of the micropores. In the calculation process, for a round micropore, D is the diameter of the micropore, and for a micropore structure with a non-round shape such as a square shape, a triangular shape and the like or other shapes, D is the equivalent hydraulic diameter of the micropore structure.

In a preferred embodiment, the microporous means consists of a plurality of micropores.

In a preferred embodiment, the microporous mechanism is an array structure composed of a plurality of micropores arranged orderly or disorderly.

In a preferred embodiment, the microporous means is a honeycomb-like array structure consisting of a plurality of micropores.

In a preferred embodiment, the micropores of the microporous means are capable of blocking the passage of liquid and allowing the passage of gas.

In a preferred embodiment, the microporous structure is hydrophobic.

In a preferred embodiment, the surface of the micropores in the microporous structure is coated with a hydrophobic coating, or the microporous structure has a hydrophobic microporous structure, or the microporous structure is made of a hydrophobic material, or the microporous structure is a combination thereof.

In a preferred embodiment, the microporous structure has a pore structure of the order of millimeters, micrometers or nanometers.

In one embodiment, a liquid return tube is disposed within the lumen of the elongate member, the liquid return tube being in fluid communication with the working bladder and the liquid injection tube, respectively.

In a preferred embodiment, the distal outlet of the liquid return tube is disposed at the distal end of the working balloon, and the distal outlet of the liquid injection tube is disposed at the proximal end of the working balloon.

In a preferred embodiment, the distal outlet of the liquid return tube is disposed at the proximal end of the working balloon, and the distal outlet of the liquid injection tube is disposed at the distal end of the working balloon.

In one embodiment, a guidewire lumen is disposed within the lumen of the catheter elongate shaft, a proximal outlet of the guidewire lumen is disposed on the catheter handle, a distal outlet of the guidewire lumen is disposed at the distal end of the elongate member, and the guidewire lumen is fluidly isolated from other components of the shockwave balloon catheter.

In one embodiment, a protective balloon is provided outside the working balloon, the protective balloon being connected to the elongate member and surrounding the working balloon.

Compare with prior art, the advantage of this application lies in:

1. the existing blast wave balloon catheter directly applies an electric field to liquid by arranging an electrode ring, the discharge requirement of high voltage and strong current needs to reduce the discharge resistance between a discharge electrode and the liquid by arranging the electrode ring with good discharge characteristic, and the diameter of the catheter balloon body after being pressed and held is obviously increased by the arrangement of the electrode ring and the implementation process thereof. The pressing and holding diameter of the catheter balloon is a core factor for limiting the passability of the catheter, and the larger outer diameter limits the application field of the catheter in clinic, so that the existing shock wave balloon catheter is difficult to be applied in the fields of coronary artery with smaller diameter of blood vessels and the like. In addition, the discharge requirement of high voltage and high current has higher requirement on the contact area of the electrode ring and liquid, and is limited by the harsh crimping diameter of the catheter, the increase of the contact area of the electrode ring and the liquid needs to be realized by increasing the length of the electrode ring, the excessively long electrode ring can cause poor compliance of the catheter, and the catheter is difficult to pass through complicated coronary arteries or cerebral vessels with excessively large bending degree. This application makes discharge voltage and electric current reduce by a wide margin through setting up the micropore mechanism, utilizes the wire directly to discharge to the outside and need not additionally set up the electrode ring and just can satisfy the requirement of discharging. The thickness of the micro-pore mechanism can be micron-sized or nano-sized, and the pressing and holding diameter of the catheter cannot be obviously influenced. The direct discharge of the wire can be realized by directly arranging a non-insulation area on the transmission wire, the pressing and holding diameter of the catheter can be greatly reduced, meanwhile, the metal electrode ring is omitted, the compliance of the catheter can be obviously improved, the trafficability of the catheter is obviously improved, and the use requirements of the fields of coronary artery, cerebral vessels and the like with smaller diameter and large bending degree of the blood vessels are met.

2. The existing blast balloon catheter adopts a structure that an electrode ring is welded on a lead, and the welding point of the electrode ring and the lead is the weakest point of the catheter. The detachment or fusion of the welded joint is one of the main causes of conduit damage. After the electrode falls off, the electrode is in direct contact with the saccule and scratches the saccule to cause the damage of the saccule, thus seriously threatening the safety of patients. This application adopts the non-insulation area who sets up on the transmission wire to arouse the target electric field, can avoid the too big wiring fusing that arouses of welding resistance, has also avoided welding strength to drop the electrode that leads to inadequately, has increased substantially the pipe security.

3. This application sets up micropore mechanism in shock wave generating unit, and the micropore that sets up on the micropore mechanism utilizes liquid self surface tension to prevent the interior liquid of working bag from contacting the uninsulated area, even directly peel off the wire like this and form uninsulated area and also can not cause the influence to the security of wire. In addition, different from the prior art in which the electrodes are exposed outside to make the electrodes directly contact with the liquid in the working balloon (i.e. the electric field is directly applied to the liquid to generate the electrohydraulic effect), the intensity of the electric field required for generating the electrohydraulic effect is high in the prior art, a high voltage of about 3000V is generally required, the high voltage makes the fluid between the electrode pairs completely breakdown and discharge, the discharge resistance is small, the current is large (generally more than 20A), once the balloon is damaged and leaks, the high voltage and the strong current pass through the human body, so that serious electric shock accidents of the human body can be caused, and even the life safety of patients and medical care personnel is damaged. The electric field generated by the application only breaks down the micro liquid bridge in the micropore, the breakdown voltage is obviously reduced, and the lowest voltage can reach 500V. In addition, the micro liquid bridge is not in contact with a non-insulation area in the electric field generating structure, and air which is not broken down exists between the micro liquid bridge and the non-insulation area, so that the generating resistance is obviously increased, and the current is greatly reduced (generally 0.1-0.2A). Therefore, the micropore mechanism can obviously reduce the threshold value (the electric field intensity threshold value required by liquid cavitation) of the liquid-electric effect cavitation, greatly reduce the discharge voltage and the discharge current, further realize the generation of strong shock waves under the condition of low voltage and weak current, obviously improve the system safety and reduce the risk of the system in the using process.

Drawings

Fig. 1 is a schematic diagram of the overall structure of a small outer diameter shockwave balloon catheter of the present application.

FIG. 2 is a schematic view of the force analysis of a liquid in a single well of the present micro-well device.

FIG. 3 is a schematic diagram of the induction of the electrooptic effect in the micropores.

FIG. 4 is a graph of the electrical resistance distribution within the working balloon.

FIG. 5 is a schematic structural view of an embodiment of the microporous mechanism of the present application.

Fig. 6 is a schematic structural diagram of a protective balloon arranged outside a working balloon of the shock wave balloon catheter.

FIG. 7 is a schematic structural view of one embodiment of a distal portion of a shockwave balloon catheter according to the present application.

Fig. 8 is a schematic view of the structure in which the non-insulating regions of the electric field generating mechanism of the shockwave balloon catheter of the present invention are arranged in parallel and facing each other.

Fig. 9 is a schematic diagram of the structure in which the non-insulated regions in the electric field generating mechanism of the shock wave balloon catheter of the present application are arranged in a crossing manner.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is further described in detail below by referring to the accompanying drawings and examples.

As shown in fig. 1 and 7, a small-outer-diameter shockwave balloon catheter comprises an axially-extending elongated member 21, a working capsule 22 arranged at the distal end portion of the elongated member 21, at least two transmission wires 23 arranged in the cavity of the elongated member 21, and an infusion tube 27, wherein the working capsule 22 is in fluid communication with the infusion tube 27, the proximal ends of the transmission wires 23 are electrically connected with an external device, the distal end portions of the transmission wires 23 extend into the working capsule 22, the transmission wires 23 arranged in the working capsule 22 are at least two, each transmission wire 23 is provided with a non-insulating region 231, the non-insulating regions 231 on different transmission wires 23 can form a target electric field, a microporous mechanism 25 is further arranged in the working capsule 22, the microporous mechanism 25 wraps the non-insulating regions 231, and the microporous mechanism 25 is an electrically insulating component, the microporous means 25 is provided with one or more micropores 251 through its wall, said micropores 251 being able to prevent the ingress of liquids by their own surface tension, so that the microporous means 25 is able to isolate the non-insulated zone 231 from the liquid flowing into the working capsule 22.

In order to effectively prevent the liquid inside the working capsule 22 from entering the micropore mechanism 25 through the micropores 251 to form a flooding discharge deterioration phenomenon, the surface properties and the dimensional structure of the micropores 251 conform to the following quantitative relationship:

in the above formula, P is the absolute pressure of the liquid in the working capsule, delta is the surface tension coefficient, D is the pore equivalent hydraulic diameter, and beta is the contact angle of the liquid on the wall surface of the micropore. In the calculation process, for a round micropore, D is the diameter of the micropore, and for a micropore structure with a non-round shape such as a square shape, a triangular shape and the like or other shapes, D is the equivalent hydraulic diameter of the micropore structure.

As shown in FIG. 2, where LD represents liquid, GS represents gas, and WB represents the wall of the micro-well, the theoretical derivation process is as follows:

surface tension F of liquid_δ＝δπD (2)

The component of the surface tension in the y direction is:

F_y＝F_δcosα＝F_δcos(π-β)＝-δπD cosβ (3)

assuming that the absolute pressure of the Liquid (LD) in the capsule is P, the force applied by the liquid pressure at the inlet of the micro-hole in the axial direction of the micro-hole can be expressed as:

when the pressure of the liquid in the working bag body is generated at the inlet of the micropore, the stress along the axial direction of the micropore is smaller than the component of the surface tension in the y direction, namely F_f<F_yIn the process, the liquid can not overcome the surface tension effect and passes through the micropores 251, the liquid can be effectively intercepted, and then the integrated electric field generation mechanism is isolated from the liquid flowing into the working capsule body through the micropores.

Formula 3-4 is substituted into available:

the above formula can also be expressed as

Therefore, as long as the inner diameter D and surface tension coefficient δ of the micropores 251 and the contact angle β with the liquid in the working capsule conform to the above formula, the liquid will be effectively intercepted and will not pass through the micropores.

The above formula also holds for non-circular or other irregular cell structures such as squares, triangles, etc., where D in formula 1 is the equivalent hydraulic diameter of the cell structure.

The conditions under which the electrohydraulic effect occurs are mainly influenced by two factors: the threshold of cavitation free energy and the electric field strength required for cavitation core formation. The existing shock wave balloon catheter directly applies an electric field to liquid to generate a liquid-electricity effect, and the free energy threshold required by cavitation generation in macroscopic bulk liquid is high. And the electric field in the bulk liquid is uniformly distributed, the electric field intensity required for generating the liquid-electric effect is high, and generally about 3000V high voltage is required. In addition, the high voltage completely discharges the fluid between the pair of electrodes, and the discharge resistance is small and the current is large (generally 20A or more). Interfacial hydrodynamics shows that the liquid in the micropores can form micro liquid bridges under the action of surface tension, the micro liquid bridges have a scale effect, and the threshold value of the liquid-electricity effect vacuole generation is obviously lower than that of the large-space macroscopic fluid in the pool. Based on the principle, the micropore mechanism 25 is arranged between the working capsule body 22 and the integrated electric field generating mechanism 23, the device is sealed and wraps the integrated electric field generating mechanism 23, micropores 251 formed in the micropore mechanism 25 can allow gas to pass through but cannot allow water to pass through, water forms microscale liquid bridges in the micropores 251, the electric field generated by the integrated electric field generating mechanism 23 only needs to puncture the microfluidic bridges in the micropores 251, and the puncture voltage is obviously reduced.

As shown in fig. 3, the micro-pores 251 can automatically intercept the liquid in the working capsule to enter the electric field generating mechanism by using the surface tension of the liquid itself. A meniscus liquid arc A is formed in a micropore in the micropore mechanism at an outlet far away from an electrode, an electric field E is applied to the meniscus liquid arc A, due to an interface effect, the free energy threshold generated by liquid cavitation at a gas-liquid interface and a solid-liquid interface is greatly reduced, and the free energy required by cavitation is obviously reduced compared with bulk phase liquid. In addition, the scale effect makes the internal electric field distribution of the meniscus liquid arc A odd, the electric field distribution is uneven, and a cavitation core is formed in an area with high interface local electric field intensity at the earliest, so that cavitation is induced. Therefore, the micropore mechanism can promote the generation of cavitation bubbles and reduce the voltage required for the formation of cavitation cores, and the minimum voltage can reach 500V.

As shown in fig. 3, since the Liquid (LD) in the working capsule 22 is not directly contacted with the non-insulating region 231, there is air (GS) between the liquid bridge and the non-insulating region 231, and the air (GS) and the Liquid (LD) are distributed with electric field, and as the electric field intensity applied on the air does not reach the breakdown critical point of the air, and the electric field applied on the meniscus arc a reaches the liquid breakdown electric field intensity critical point, a breakdown arc can be generated in the liquid arc. In the discharging process, the electrode needs to pass through the non-punctured insulating air for discharging, electrons need to be conducted through the air layer and the meniscus arc A, and the conduction resistance is obviously increased. As shown in fig. 4, since the resistance R2 of the meniscus arc a is relatively small, the process resistance is mainly due to the resistances R1 and R3 of the air layer on both sides of the micro-hole, and thus the current is greatly reduced (generally 0.1A to 0.2A). Therefore, through the induction of the micropore mechanism 25, the threshold value of the liquid-electricity effect vacuole can be obviously reduced, the discharge voltage and the discharge current are greatly reduced, and then the strong shock wave can be generated under the condition of low voltage and low current, so that the system safety is obviously improved, and the risk of the system in the using process is reduced.

As shown in fig. 7, the non-insulation region 231 is implemented by directly peeling off the insulation layer on the transmission wire 23. In one embodiment, a plurality of pairs of non-insulated regions 231 are disposed on two of the transmission wires 23 to form a plurality of electric fields. Preferably, as shown in fig. 8, a plurality of pairs of non-insulating regions are arranged side by side in an opposing manner; alternatively, as shown in fig. 9, a plurality of pairs of non-insulating regions are arranged to intersect. The plurality of non-insulated regions on each of the transmission conductors are connected in parallel by a connection conductor. The connecting wires and the transmission wires are designed in an integrated mode. The existing blast wave balloon catheter directly applies an electric field to liquid by arranging an electrode ring, the discharge requirement of high voltage and strong current needs to reduce the discharge resistance between a discharge electrode and the liquid by arranging the electrode ring with good discharge characteristic, and the diameter of the catheter balloon body after being pressed and held is obviously increased by the arrangement of the electrode ring and the implementation process thereof. The pressing and holding diameter of the catheter balloon is a core factor for limiting the passability of the catheter, and the larger outer diameter limits the application field of the catheter in clinic, so that the existing shock wave balloon catheter is difficult to be applied in the fields of coronary artery with smaller diameter of blood vessels and the like. In addition, the discharge requirement of high voltage and high current has higher requirement on the contact area of the electrode ring and liquid, and is limited by the harsh crimping diameter of the catheter, the increase of the contact area of the electrode ring and the liquid needs to be realized by increasing the length of the electrode ring, the excessively long electrode ring can cause poor compliance of the catheter, and the catheter is difficult to pass through complicated coronary arteries or cerebral vessels with excessively large bending degree. This application makes discharge voltage and electric current reduce by a wide margin through setting up the micropore mechanism, utilizes the transmission wire directly to externally discharge and need not additionally set up the electrode ring and just can satisfy the requirement of discharging. The thickness of the micro-pore mechanism can be micron-sized or nano-sized, and the pressing and holding diameter of the catheter cannot be obviously influenced. The direct discharge of the transmission lead can be realized by directly arranging the non-insulation area on the transmission lead, the pressing and holding diameter of the catheter can be greatly reduced, meanwhile, the metal electrode ring is omitted, the compliance of the catheter can be obviously improved, the trafficability of the catheter is obviously improved, and the use requirements of the fields of coronary artery, cerebral vessels and the like with smaller diameter and large bending degree of the blood vessels are met. In addition, the existing shock wave balloon catheter adopts a structure that an electrode ring is welded on a lead, and the welding point of the electrode ring and the lead is the weakest point of the catheter. The detachment or fusion of the welded joint is one of the main causes of conduit damage. After the electrode falls off, the electrode is in direct contact with the saccule and scratches the saccule to cause the damage of the saccule, thus seriously threatening the safety of patients. This application adopts the non-insulation area who sets up on the transmission wire to arouse the target electric field, can avoid the too big wiring fusing that arouses of welding resistance, has also avoided welding strength to drop the electrode that leads to inadequately, has increased substantially the pipe security.

In one embodiment, an electric field strengthening layer is disposed on the non-insulating region, and the electric field strengthening layer is made of a metal or non-metal material with high conductivity, high stability and low electrode loss. Preferably, the material of the electric field strengthening layer is gold, silver, platinum, copper, steel, tungsten, graphene and corresponding alloy or composite material, or the electric field strengthening layer is a combination of the above materials. The combination comprises the cooperation of any two structures or the combination of any three structures.

In one embodiment, as shown in fig. 1, a liquid return tube 26 is disposed in the cavity of the elongate member 21, and the liquid return tube 26 is in fluid communication with the working capsule 22 and the liquid injection tube 27, respectively. When the shock wave is generated, the pressure inside the working capsule 22 rises, and the liquid return pipe 26 is arranged to avoid the risk of balloon breakage caused by too high pressure inside the working capsule 22. In a preferred embodiment, the distal outlet of the liquid return tube 26 is arranged at the distal end of the working capsule 22, and the distal outlet of the liquid injection tube 27 is arranged at the proximal end of the working capsule 22, which can improve the fluid flow efficiency and rapidly relieve the pressure. The microporous mechanism 25 is a tube body, and two ends 252 of the microporous mechanism are hermetically connected to the liquid return tube 26. In another embodiment, the distal outlet of the return tube is disposed at the proximal end of the working capsule 22, and the distal outlet of the injection tube 27 is disposed at the distal end of the working capsule 22.

As shown in fig. 5, the micropore mechanism 25 is composed of a plurality of micropores 251 penetrating through the tube wall thereof. The micropores 251 are arranged orderly or disorderly to form a micropore array, or the micropores form a honeycomb array. The surface property and the size structure of the micropores meet the requirement of the formula 1, so that the micropores can prevent liquid from passing through and allow gas to pass through. In a preferred embodiment, the microporous means is hydrophobic to further impede passage of liquid through the micropores. The microporous structure can be made hydrophobic by means commonly used in the art, such as coating the surface of the micropores with a hydrophobic coating, or designing the micropores with a hydrophobic structure, or making the microporous structure of a hydrophobic material, or a combination thereof. So that the liquid can be prevented from passing through the micropores even if the size of the micropores is in the order of millimeters, as long as the requirement of formula 1 is met. Therefore, the micropore mechanism of the utility model can select the pore structure of millimeter level, micron level or nanometer level.

In one embodiment, as shown in fig. 7, a guide wire lumen 29 is disposed within the lumen of the elongate member 21, a proximal outlet of the guide wire lumen 29 is disposed on the catheter handle, the guide wire lumen 29 extends through the entire lumen of the elongate member 21, and a distal outlet thereof extends beyond the distal end of the elongate member 21, the guide wire lumen 29 is fluidly isolated from other components of the shock wave balloon catheter 2 to prevent liquid from entering the interior of the shock wave balloon catheter 2 through the guide wire lumen 29. The guidewire lumen 29 is used to receive a guidewire for guiding the catheter to a desired location. In one embodiment, the microporous mechanism 25 is a tube, and both ends 252 of the microporous mechanism 25 are respectively connected with the guide wire lumens in a sealing manner.

In one embodiment, as shown in fig. 6, a protective capsule 28 is provided outside the working capsule 22, said protective capsule 28 being in sealed connection with the elongate member 21 and enveloping the working capsule 22. During operation of the system, if the working capsule 22 is damaged, the body tissue is not directly exposed to the electric field, thereby avoiding the risk of electric shock.

The above description of the present invention is intended to enable persons skilled in the art to understand the contents of the present invention and to implement the present invention without limiting the scope of the present invention, and all equivalent changes or modifications made according to the spirit of the present invention should be covered by the present invention.

Claims

1. A shock wave sacculus catheter with small outer diameter comprises an axially extending elongated member, a working sac body arranged at the distal end part of the elongated member, transmission leads arranged in the cavity of the elongated member and a liquid injection pipe, wherein the working sac body is in fluid communication with the liquid injection pipe, the proximal ends of the transmission leads are electrically connected with external equipment, the shock wave sacculus catheter is characterized in that the distal end part of the transmission leads extends into the working sac body, at least two transmission leads are arranged in the working sac body, each transmission lead is provided with a non-insulating area, a target electric field can be formed between the non-insulating areas on different transmission leads, a micropore mechanism is further arranged in the working sac body and wraps the non-insulating areas, the micropore mechanism is an electrically insulating part and is provided with one or more micropores penetrating through the wall of the micropore mechanism, the micro-pores can prevent liquid from entering by utilizing the surface tension of the micro-pores, so that the micro-pore mechanism can isolate the non-insulating area from the liquid flowing into the working capsule.

2. The small outer diameter shockwave balloon catheter of claim 1, wherein said uninsulated region is achieved by directly stripping an insulation layer on said transmission wire.

3. The small outer diameter shockwave balloon catheter of claim 2, wherein a plurality of pairs of uninsulated regions are provided on both of said transmission wires to form a plurality of electric fields.

4. The small outer diameter shockwave balloon catheter according to claim 3 wherein a plurality of pairs of uninsulated regions are disposed in opposing side-by-side or intersecting relationship.

5. The small outer diameter shockwave balloon catheter of claim 3, wherein a plurality of uninsulated regions on each said transmission wire are connected in parallel by connecting wires.

6. The small outer diameter shockwave balloon catheter of claim 1, wherein an electric field enhancement layer is provided on said non-insulated region, said electric field enhancement layer being made of a metal or non-metal material with high conductivity, high stability, low electrode loss.

7. The small outer diameter shockwave balloon catheter of claim 1, wherein said micropores have surface properties and dimensional structure conforming to the following quantitative relationship:

wherein P is the absolute pressure of the liquid in the working capsule, delta is the surface tension coefficient, D is the equivalent hydraulic diameter of the pores, and beta is the contact angle of the liquid on the wall surface of the micropores.

8. The small outer diameter shockwave balloon catheter of claim 7, wherein said microporous means is an array structure comprised of a plurality of micropores arranged in an orderly or unordered arrangement, or said microporous means is a honeycomb array structure comprised of a plurality of micropores.

9. The small outer diameter shockwave balloon catheter according to claim 7, wherein said micropores in said microporous means are capable of blocking the passage of liquid while allowing the passage of gas.

10. The small outer diameter shockwave balloon catheter of claim 1, wherein said microporous means is hydrophobic.