CN120859642A - Balloon type ablation catheter with self-adaptive lumen wall microstructure - Google Patents

Abstract

The invention relates to the technical field of medical appliances and discloses a balloon type ablation catheter with a self-adaptive lumen wall microstructure, which comprises a catheter shaft, wherein the catheter shaft is used for being matched with a guide wire to be introduced into a target lumen, the balloon is arranged at one end of the catheter shaft and is inflated and deflated through inflation and deflation of an inflation medium, an electrode action area comprises an electrode substrate, a plurality of flexible electrodes and a hydrogel layer, the electrode substrate is arranged on the surface of the balloon, the plurality of flexible electrodes are arranged on the electrode substrate, the hydrogel layer is coated with the plurality of flexible electrodes and the electrode substrate, and the hydrogel layer can conduct electricity and can adapt to the wall structure of a lumen tissue along with the deformation of the balloon.

Description

Balloon type ablation catheter with self-adaptive lumen wall microstructure

Technical Field

The invention relates to the technical field of medical instruments, in particular to a balloon type ablation catheter with a self-adaptive lumen wall microstructure.

Background

Endoluminal tumors (such as cholangiocarcinoma and pancreatic cancer) are diseases with poor prognosis in digestive system malignant tumors, and the treatment mainly comprises surgical excision, but the problems of low radical excision rate, poor prognosis and the like are easily caused due to complex anatomical positions and narrow surgical space. The pulsed electric field ablation technique (PFA) developed in recent years is considered to be suitable for intracavity tumor ablation, and the technique induces apoptosis through irreversible electroporation effect to realize tissue ablation, and has the advantages of cell selectivity, electric field dependence, nonthermal injury and physical targeting. Compared with the traditional ablation technology, the PFA is more accurate in tissue damage control, higher in ablation boundary resolution, more suitable for heat-sensitive lumen tissue ablation, and does not damage the integrity of the tissue scaffold.

The practical application of PFA technology in intracavity tumor therapy still faces many challenges, one of the most important problems being the coupling efficiency of the bioelectro-tissue interface formed by the electrode and the lumen wall. The electronic device is essentially different from biological tissues in the charge transfer mode, wherein the charges in the electronic device take electrons as carriers, the transmission speed is high and the directivity is strong, and in the biological tissues, the charges take ions as carriers, the transmission speed is low and the dynamic adjustment of the transmembrane potential of a cell membrane and an ion channel is dependent. Thus, the biological interface formed at the junction of the electronic device and the biological tissue becomes a critical factor affecting the efficiency of energy delivery.

In summary, the existing ablation catheter has the following problems:

1. the electrode has an excessively large elastic modulus or deformation degree compared with human tissue, and is difficult to be attached to the wall of the lumen of the human body for deformation.

2. The wall of the tube cavity is a non-flat surface due to the existence of the microstructure, and even if the wall is in close contact with the flexible electrode, a gas or liquid gap is easily caused, so that insufficient coupling of a contact interface is caused, and the energy transfer efficiency is influenced.

3. The electrode and the biological tissue are respectively electronically conductive and ionically conductive in a charge transfer mode, the contact interface requirement is high, otherwise, the interface impedance is too large, so that the energy distribution of an electric field is uneven, and the ablation effect is affected.

Disclosure of Invention

The invention aims to provide a balloon type ablation catheter with a self-adaptive lumen wall microstructure, which aims to solve or improve at least one of the technical problems.

In order to achieve the aim, the invention provides a balloon type ablation catheter with a self-adaptive lumen wall microstructure, which comprises the following components:

a catheter shaft for introduction into a target lumen in cooperation with a guidewire;

The balloon is arranged at one end of the catheter shaft and realizes expansion and contraction by filling and discharging an expansion medium;

The electrode action area comprises an electrode substrate, a plurality of flexible electrodes and a hydrogel layer, wherein the electrode substrate is arranged on the surface of the balloon, the flexible electrodes are arranged on the electrode substrate, the hydrogel layer is used for coating the flexible electrodes and the electrode substrate, and the hydrogel layer can conduct electricity and adapt to the wall surface structure of the lumen tissue along with the deformation of the balloon.

Optionally, the hydrogel layer includes:

A conductive hydrogel coated on the surface of the flexible electrode;

and the non-conductive hydrogel is coated on the surface of the electrode substrate and fills gaps among the plurality of flexible electrodes.

Optionally, an end of the balloon remote from the catheter shaft is provided with a leading end.

Optionally, the method further comprises:

an outer sheath slidably wrapped around the catheter shaft, the electrode active region being switchable between a wrapped and an exposed state by controlling the sliding of the outer sheath;

the operating handle is arranged at one end of the catheter shaft, which is far away from the balloon, and a control component for controlling the outer sheath tube to slide is arranged on the operating handle.

Optionally, the control assembly includes:

A sliding button slidably disposed on the operating handle;

And the fixing piece is fixedly connected with the outer sheath tube and the sliding button respectively.

Optionally, the operating handle includes the base member and set up in handle front end and the handle rear end at base member both ends, the handle front end sets up towards the flexible restraint mouth of sheath pipe, the handle rear end with the pipe shaft is fixed mutually.

Optionally, a wire guiding cavity, an expansion medium guiding cavity and a wire guiding cavity are arranged in the catheter shaft, and a plurality of first side holes used for the expansion medium guiding cavity to be communicated with the balloon and a plurality of second side holes used for the wire guiding connection in the wire guiding cavity to be used for the wire penetrating connection of the flexible electrode are formed in the side wall of the catheter shaft.

Optionally, one end of the catheter shaft away from the balloon is communicated with a Y-shaped valve, the Y-shaped valve is communicated with an inflation medium interface and an instrument channel, the inflation medium interface is communicated with the inflation medium conducting cavity, the instrument channel is communicated with the guide wire cavity, and the instrument channel is provided with a sealing element.

Optionally, the flexible electrode assembly further comprises a power cable, wherein the power cable is introduced into the wire cavity and is electrically connected with a plurality of flexible electrodes.

Optionally, the flexible electrode assembly further comprises a sensing signal cable, wherein the sensing signal cable is introduced into the wire cavity and is electrically connected with a plurality of flexible electrodes.

The invention has the following technical effects that the balloon is inflated and pressurized through the catheter shaft, the flexible electrode and the hydrogel layer coated on the upper part of the flexible electrode are supported, the different-sized lumen is satisfied, and the hydrogel layer is contacted with the lumen wall. Under the influence of balloon pressure, the hydrogel layer may deform to conform to the lumen wall microstructure and fill the interstices of the gas or liquid at the bioelectric tissue interface. And then applying voltage to part or all of the flexible electrodes through the lead wires to form a stable columnar electric field, and ablating a target area, compared with the traditional balloon electrode catheter, through the self-adaptive lumen wall microstructure of the hydrogel layer, the effective contact area of the electrode and tissues is improved, interface impedance is reduced, electric field energy is uniformly distributed, and energy transfer efficiency is improved.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the application. In the drawings:

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

FIG. 2 is a cross-sectional view of the electrode active region of the present invention;

FIG. 3 is a cross-sectional view of the operating handle of the present invention;

FIG. 4 is a schematic view of the hydrogel layer of the present invention in contact with a lumen wall.

In the figure, 1, a guide end, 2, a balloon, 3, an electrode action area, 31, an electrode substrate, 32, a flexible electrode, 33, conductive hydrogel, 34, nonconductive hydrogel, 4, a catheter shaft, 41, a guide wire cavity, 42, a first side hole, 43, an inflation medium conduction cavity, 44, a wire cavity, 45, a second side hole, 5, an outer sheath, 6, an operation handle, 61, a handle front end, 62, a matrix, 63, a handle rear end, 7, a control component, 71, a sliding button, 72, a fixing piece, 8, a Y-shaped valve, 81, an inflation medium interface, 82, an instrument channel, 83, a sealing piece, 9, a power cable, 10, a sensing signal cable, 11 and a lumen tissue.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

In order that the above-recited objects, features and advantages of the present invention will become more readily apparent, a more particular description of the invention will be rendered by reference to the appended drawings and appended detailed description.

Referring to fig. 1-4, the present invention provides a balloon-type ablation catheter with an adaptive lumen wall microstructure, comprising:

A catheter shaft 4 for introduction into a target lumen in cooperation with a guidewire;

The balloon 2 is arranged at one end of the catheter shaft 4, and is inflated and deflated by inflation and deflation of an inflation medium, and the inflation medium is gas or liquid;

the electrode action area 3 comprises an electrode substrate 31, a plurality of flexible electrodes 32 and a hydrogel layer, wherein the electrode substrate 31 is arranged on the surface of the balloon 2, the plurality of flexible electrodes 32 are arranged on the electrode substrate 31, the hydrogel layer is coated with the plurality of flexible electrodes 32 and the electrode substrate 31, and the hydrogel layer can conduct electricity and adapt to the wall surface structure of the lumen tissue 11 along with the deformation of the balloon 2.

Further, the elastic modulus (10-1000 kPa) of the hydrogel layer, the conductivity (0.1-1000S/m) of the hydrogel layer is adjustable, the thickness of the hydrogel layer is 50-1500 mu m, and the hydrogel layer can carry out pulse electric field energy delivery within the electric field intensity range of 1-50 kV/cm.

Further, the flexible electrode 32 is prepared by a micro-nano manufacturing process or a printing process, has good flexibility and conductivity, the thickness (10-1000 μm), the line width (0.1-10 mm) and the spacing (0.1-10 mm) of the flexible electrode 32 are adjustable, the flexible electrode 32 is divided into a plurality of groups, the polarities of the electrodes between two adjacent groups are opposite, and each group of electrodes can independently control the electrifying parameters.

In one embodiment of the present invention, the hydrogel layer comprises:

A conductive hydrogel 33 applied to the surface of the flexible electrode 32;

a non-conductive hydrogel 34, coated on the surface of the electrode substrate 31, fills the gaps between the plurality of flexible electrodes 32, and serves to improve the current transfer efficiency of the electrode-tissue interface.

The conductive hydrogel 33 is a double-network hydrogel, the matrix is acrylamide and sodium alginate, the initiator is N, N' -methylene bisacrylamide, and the conductive hydrogel is doped with conductive materials, wherein the conductive materials are any one or combination of silver nano powder, silver nano sheets, silver nano wires, PEDOT: PSS, platinum, carbon nano tubes, graphene and gold nano wires.

Further, the non-conductive hydrogel 34 and a part of the flexible electrode 32 are coated with an insulating layer for preventing current leakage and electric field distribution from being affected, and the insulating layer is any one or combination of parylene, polyimide, polyurethane, epoxy resin and acrylic acid.

In one embodiment of the invention, the end of the balloon 2 remote from the catheter shaft 4 is provided with a leading end 1, the leading end 1 being in communication with the guidewire lumen 41 of the catheter shaft 4.

In one embodiment of the present invention, further comprising:

An outer sheath 5 slidably wrapped around the catheter shaft 4, the electrode active region 3 being switched in a wrapped and exposed state by controlling the sliding of the outer sheath 5;

an operation handle 6 is arranged at one end of the catheter shaft 4 far away from the balloon 2, and a control component 7 for controlling the outer sheath 5 to slide is arranged on the operation handle 6.

The outer sheath 5 is used to prevent snagging of the hydrogel layer during delivery and to control exposure of the electrode application zone 3 by the control assembly 7 after the balloon 2 reaches the target area.

In one embodiment of the present invention, the control assembly 7 comprises:

a slide button 71 slidably provided on the operation handle;

the fixing member 72 is fixedly connected to the outer sheath 5 and the slide button 71, respectively.

In one embodiment of the present invention, the operation handle 6 includes a base 62, and a handle front end 61 and a handle rear end 63 provided at both ends of the base 62, the handle front end 61 being provided with a restraining port extending toward the outer sheath 5, and the handle rear end 63 being fixed to the catheter shaft 4.

The telescopic direction is the sliding direction, and the restraint opening is used for controlling the relative position of the outer sheath tube 5 and the operating handle 6 in the sliding process so as to facilitate the handle operation.

In one embodiment of the present invention, a guide wire cavity 41, an inflation medium conducting cavity 43 and a wire cavity 44 are arranged in the catheter shaft 4, and a plurality of first side holes 42 for communicating the inflation medium conducting cavity 43 with the balloon 2 and a plurality of second side holes 45 for threading wires in the wire cavity 44 to connect the flexible electrode 32 are arranged on the side wall of the catheter shaft 4.

The guidewire lumen 41 is used to guide guidewire assistance in positioning, the inflation medium conduction lumen 43 is used for inflation or filling of the balloon 2 through the first side hole 42, and the guidewire lumen 44 is used for receiving and connecting the sensing signal wire and the electrode connection wire through the second side hole 45.

In one embodiment of the invention, the end of the catheter shaft 4 remote from the balloon 2 is connected with a Y-valve 8, the Y-valve 8 is fixed with the handle rear end 63, the Y-valve 8 is connected with an inflation medium port 81 and an instrument channel 82, the inflation medium port 81 is communicated with the inflation medium conduction cavity 43, the instrument channel 82 is communicated with the guide wire cavity 41, and the instrument channel 82 is provided with a sealing element 83.

In one embodiment of the present invention, the power cable 9 is further included, and the power cable 9 is introduced into the wire cavity 44 and electrically connected to the plurality of flexible electrodes 32.

The connectors of the power cable 9 include a high voltage connector and a low voltage connector for connecting the positive and negative electrodes of the flexible electrode 32, respectively, to achieve the transmission of energy.

In one embodiment of the present invention, the sensor signal cable 10 is also included, and the sensor signal cable 10 is introduced into the wire cavity 44 and electrically connected to the plurality of flexible electrodes 32.

The operation principle is that a guide wire is led into a target lumen through a guide wire cavity 41, then a catheter is pushed to a target treatment area along the guide wire, after the balloon 2 reaches a target position, a sliding button 71 is used for sliding an outer sheath 5 backwards, so that the balloon 2 and an electrode action area 3 are exposed for subsequent treatment, then gas or liquid is injected into an inflation medium conduction cavity 43 through an inflation medium interface 81, so that the balloon 2 is expanded, the electrode action area 3 on the surface of the balloon 2 is driven to expand, a hydrogel layer coated on a flexible electrode 32 is contacted with lumen tissues, wherein the hydrogel comprises a conductive hydrogel 33 and a non-conductive hydrogel 34, the surface of the lumen tissues 11 is provided with a microstructure instead of a flat surface, when the balloon 2 is pressed to drive the flexible electrode 32 and the hydrogel to expand, the hydrogel layer is deformed under the pressure, then a gas or liquid gap generated at a bioelectric interface due to the fact that a conventional electrode cannot deform is filled, the actual contact area is increased, the interface contact impedance is reduced, and then a pulse current is provided to the flexible electrode 32 and the conductive hydrogel 33 through a power cable 9 and a connected lead, so that the conductive hydrogel 33 is uniformly transferred to the target tissues, and the target tissues are ablated and the uniform regions are realized. Meanwhile, monitoring data such as tissue resistance and the like are transmitted to external equipment through the sensing signal cable 10, and the ablation effect is evaluated in real time and parameters are adjusted. After ablation is completed, gas or liquid is discharged to the inflation medium conductive cavity 43 through the inflation medium port 81 to cause the balloon 2 to contract, and then the sliding button 71 is operated to slide the outer sheath 5 toward the catheter tip so that the electrode application area 3 of the balloon 2 is covered by the outer sheath 5, and then the catheter shaft 4 is withdrawn along the guide wire.

In the description of the present invention, it should be understood that the terms "longitudinal," "transverse," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like indicate or are based on the orientation or positional relationship shown in the drawings, merely to facilitate description of the present invention, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the present invention.

The above embodiments are only illustrative of the preferred embodiments of the present invention and are not intended to limit the scope of the present invention, and various modifications and improvements made by those skilled in the art to the technical solutions of the present invention should fall within the protection scope defined by the claims of the present invention without departing from the design spirit of the present invention.

Claims (10)

1. A balloon ablation catheter with an adaptive lumen wall microstructure, comprising:

A catheter shaft (4) for introduction into a target lumen in cooperation with a guidewire;

The balloon (2) is arranged at one end of the catheter shaft (4) and realizes expansion and contraction by filling and discharging an expansion medium;

The electrode action area (3) comprises an electrode substrate (31), a plurality of flexible electrodes (32) and a hydrogel layer, wherein the electrode substrate (31) is arranged on the surface of the balloon (2), the flexible electrodes (32) are arranged on the electrode substrate (31), the hydrogel layer is coated with the flexible electrodes (32) and the electrode substrate (31), and the hydrogel layer can conduct electricity and adapt to the wall surface structure of the lumen tissue (11) along with the deformation of the balloon (2).

2. A balloon ablation catheter of adaptive lumen wall microstructure as recited in claim 1, characterized in that the hydrogel layer comprises:

A conductive hydrogel (33) applied to the surface of the flexible electrode (32);

A non-conductive hydrogel (34) applied to the surface of the electrode substrate (31) to fill gaps between the plurality of flexible electrodes (32).

3. Balloon-type ablation catheter with adaptive lumen wall microstructure according to claim 1, characterized in that the end of the balloon (2) remote from the catheter shaft (4) is provided with a guiding end (1).

4. The balloon ablation catheter of an adaptive lumen wall microstructure of claim 1, further comprising:

an outer sheath (5) slidably wrapped around the catheter shaft (4), the electrode active region (3) being switchable between a wrapped and an exposed state by controlling the sliding of the outer sheath (5);

The operation handle (6) is arranged at one end, far away from the balloon (2), of the catheter shaft (4), and a control assembly (7) for controlling the sliding of the outer sheath tube (5) is arranged on the operation handle (6).

5. A balloon ablation catheter with adaptive lumen wall microstructure according to claim 4, wherein the control assembly (7) comprises:

A slide button (71) slidably provided on the operation handle;

and the fixing piece (72) is fixedly connected with the outer sheath tube (5) and the sliding button (71) respectively.

6. The balloon ablation catheter with the self-adaptive lumen wall microstructure according to claim 4, wherein the operation handle (6) comprises a base body (62), a handle front end (61) and a handle rear end (63) which are arranged at two ends of the base body (62), the handle front end (61) is provided with a restraining port which stretches towards the outer sheath tube (5), and the handle rear end (63) is fixed with the catheter shaft (4).

7. Balloon ablation catheter with self-adaptive lumen wall microstructure according to claim 1, characterized in that a guide wire lumen (41), an inflation medium conduction lumen (43) and a wire lumen (44) are arranged in the catheter shaft (4), and a plurality of first side holes (42) for the inflation medium conduction lumen (43) to communicate with the balloon (2) and a second side hole (45) for the wire threading in the wire lumen (44) to connect with the flexible electrode (32) are arranged on the side wall of the catheter shaft (4).

8. The balloon ablation catheter of the self-adaptive lumen wall microstructure according to claim 7, wherein one end of the catheter shaft (4) far away from the balloon (2) is communicated with a Y-valve (8), the Y-valve (8) is communicated with an inflation medium interface (81) and an instrument channel (82), the inflation medium interface (81) is communicated with the inflation medium conduction cavity (43), the instrument channel (82) is communicated with the guide wire cavity (41), and the instrument channel (82) is provided with a sealing element (83).

9. The balloon ablation catheter of claim 7, further comprising a power cable (9), wherein the power cable (9) is introduced into the guidewire lumen (44) and electrically connected to a plurality of the flexible electrodes (32).

10. The balloon ablation catheter of claim 7, further comprising a sensing signal cable (10), the sensing signal cable (10) being introduced into the guidewire lumen (44) and electrically connected to a plurality of the flexible electrodes (32).