CN215874912U - Ablation catheter and medical device - Google Patents

Abstract

The utility model provides an ablation catheter and a medical device, wherein the medical device comprises an ablation catheter and a host, wherein the ablation catheter comprises a tube assembly and an ablation electrode assembly; the ablation electrode assembly is of a pipe net structure and is sleeved on the outer surface of the distal end of the pipe assembly, the proximal end of the ablation electrode assembly is connected to the pipe assembly, the ablation electrode assembly is configured to be capable of expanding or contracting along the radial direction of the pipe assembly, the ablation electrode assembly comprises at least one ablation part, and the ablation part is wound around a circle along the circumferential direction of the pipe assembly; the host is configured to provide ablation energy to the ablation electrode assembly. When the medical device is used for executing catheter ablation, the ablation part is at least partially abutted against a target position of a target lumen, ablation energy is applied to form a circumferentially continuous ablation focus, and ablation efficiency is improved.

Description

Ablation catheter and medical device

Technical Field

The utility model relates to the technical field of medical instruments, in particular to an ablation catheter and a medical device.

Background

Atrial fibrillation is a common persistent arrhythmia, the incidence of which increases with age, with the incidence of 10% in people over 75 years of age. The atrial excitation frequency during atrial fibrillation is as high as 300-600 times/min, the frequency is high, the atrial excitation frequency is irregular, the atrium loses effective contraction function, and the health of a patient is seriously harmed. The pulmonary vein is the most common localized focus of atrial fibrillation due to the presence of pulmonary vein muscle cuffs, which are the homologous myocardial tissue to atrial myocytes that extend from the left atrium to the pulmonary veins.

Currently, the common clinical treatment methods for heart rate disorders such as atrial fibrillation include radiofrequency ablation and cryoablation, and the success of ablation depends mainly on the quality and sufficiency of the lesions generated during the operation: sufficient damage can destroy the tissue causing the arrhythmia or sufficiently interfere with or isolate abnormal electrical conduction within the myocardial tissue. However, excessive ablation may have an effect on healthy and nervous tissue. Moreover, radio frequency ablation and cryoablation respectively have some disadvantages, for radio frequency ablation, the operation time is long, the operation level requirement of an operator is high, radio frequency ablation is thermal injury, pain is caused during ablation, and pulmonary vein stenosis is easy to generate after operation, and besides, radio frequency energy can also affect healthy tissues or nerve tissues, such as esophagus or phrenic nerve injury, tissue scabbing and further embolism problem. For cryoablation, the damage rate to the phrenic nerve is higher.

Another ablation method in the prior art is cardiac pulsed electric field ablation, which is a novel ablation method using a pulsed electric field as energy. The pulse electric field ablation is to adopt a plurality of short-time high-voltage electric pulses to release ablation energy by designing a proper pulse electric field, so that the ablation process is non-thermal energy ablation, the myocardial cells are effectively induced to generate electroporation, extracellular ions enter the cells, and the myocardial cells are broken and die. Different tissue cells have different threshold values for voltage penetration, so that the myocardial cells with lower threshold values for the pulse electric field can be selectively treated by adopting the pulse electric field ablation, and other myocardial cells with higher threshold values for the pulse electric field are reversible even if damaged in the ablation process, namely, the myocardial conduction system can be directionally damaged by the pulse electric field ablation, so that complications caused by damage to healthy tissues can be avoided.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide an ablation catheter and a medical device, which can be used for radio frequency ablation or pulsed electric field ablation and have good ablation effect.

To achieve the above objects, the present invention provides an ablation catheter comprising a tube assembly and an ablation electrode assembly; the ablation electrode assembly is of a tube net structure and is arranged at the distal end of the tube assembly, the proximal end of the ablation electrode assembly is connected to the tube assembly, the ablation electrode assembly is configured to be capable of expanding or contracting along the radial direction of the tube assembly, and the ablation electrode assembly comprises at least one ablation part which surrounds a circle along the circumferential direction of the tube assembly.

Optionally, the ablation electrode assembly is made of a material having self-expandability and is pre-shaped in a radially-expanded state.

Optionally, the tube assembly comprises a tube body and a balloon sleeved on the outer surface of the distal end of the tube body, the ablation electrode assembly is sleeved on the outer surface of the balloon, and the proximal end of the ablation electrode assembly is connected with the tube body; the balloon is adapted to abut an inner surface of the ablation electrode assembly when expanded and to provide a radially outward supporting force to the ablation electrode assembly.

Optionally, the ablation electrode assembly further comprises a non-ablation portion; the material coverage of the ablation portion is greater than the material coverage of the non-ablation portion.

Optionally, the ablation electrode assembly further comprises a non-ablation portion; the softness of the ablation portion is greater than the softness of the non-ablation portion.

Optionally, the ablation portion is for at least partially abutting a target location; the ablation catheter further includes a monitoring electrode assembly disposed at least partially on an outer surface of the ablation portion and configured to monitor whether the ablation portion is in close proximity to the target location.

Optionally, the monitoring electrode assembly includes a first electrode and a plurality of second electrodes, the first electrode is connected to the tube assembly, the second electrodes are disposed in the ablation portion and arranged along the circumference of the ablation electrode assembly, and a loop is formed between the first electrode and the second electrode.

Optionally, the second electrode is spaced from the distal end of the ablation portion by a distance 1/3-2/3 of the axial length of the ablation portion in the axial direction of the tube assembly.

Optionally, the ablation electrode assembly comprises first and second axially connected portions, a proximal end of the first portion being connected to the tube assembly; the first part comprises a conductive component and an insulating layer, the conductive component is used for being connected with an external host to receive ablation energy provided by the host, and the insulating layer is arranged on the surface of the conductive component; at least part of the structure of the second portion is configured to be electrically conductive and includes at least one of the ablation portions, wherein one of the ablation portions is electrically connected to the electrically conductive member of the first portion to receive ablation energy delivered by the electrically conductive member.

Optionally, the second portion integrally forms one of the ablation portions.

Optionally, the second portion comprises two ablation portions and a first connecting portion, the two ablation portions are respectively a first ablation portion and a second ablation portion, and the first ablation portion and the second ablation portion are arranged at intervals along the axial direction of the tube assembly and are connected through the first connecting portion; the first ablation part is closer to the first part and is electrically connected with the conductive component of the first part, and the second ablation part is connected with a conductive structure which is used for being connected with an external host and transmitting ablation energy provided by the host to the second ablation part; the first connection portion is configured to have an insulating property.

Optionally, in the axial direction of the ablation catheter, the length of the ablation part is 2mm to 5mm, and the length of the first connection part is 3mm to 8 mm; and/or the distance between the center of the first connecting part and the center of the ablation electrode assembly is 0-8 mm in the axial direction of the ablation catheter.

Optionally, the ablation electrode assembly comprises a plurality of metal rods and a plurality of reinforcing ribs, and two adjacent metal rods are connected with each other in a smooth transition mode through the reinforcing ribs.

Optionally, the tube assembly comprises a tube body and a balloon arranged at the distal end of the tube body, the ablation electrode assembly is sleeved on the outer surface of the balloon, and the proximal end of the ablation electrode assembly is connected with the tube body; the balloon is configured to selectively provide a radially outward supporting force to the ablation electrode assembly.

Optionally, the ablation catheter has a first operating condition in which the balloon and the ablation electrode assembly are both in an expanded condition and an outer surface of the balloon abuts an inner surface of the ablation electrode assembly to provide the supporting force; in the second operational configuration, the balloon is deflated and the ablation electrode assembly is in an expanded or non-fully expanded state, with the outer surface of the balloon being spaced from the inner surface of the ablation electrode assembly.

Optionally, the tube body comprises an inner tube, an outer tube and a guiding head, the outer tube is sleeved outside the inner tube, the outer tube and the inner tube can generate relative axial movement, and the guiding head is connected to the distal end of the inner tube and is communicated with the inner tube; the balloon is sleeved on the outer surface of the far end of the inner tube body, the far end of the balloon is connected with the outer surface of the guide head in a sealing mode, and the near end of the balloon is connected with the far end of the outer tube body in a sealing mode.

Optionally, the ablation catheter further comprises an infusion tube in communication with the lumen of the balloon and for infusing fluid into the lumen; a gap between the inner and outer tubes is used to vent the fluid from the lumen of the balloon.

Optionally, the ablation catheter further comprises a temperature sensor and/or a positioning sensor, the temperature sensor and/or the positioning sensor being disposed on the inner tube body and located in a region where the balloon is located.

Optionally, the distal end of the ablation electrode assembly is connected to the guide head.

Optionally, the distal end of the ablation electrode assembly is an open end, and the diameter of the open end is increased from small to large when the ablation electrode assembly is expanded.

In order to achieve the above object, the present invention further provides a medical device, comprising a main machine and the ablation catheter as described in any one of the above, wherein the main machine is connected with the ablation catheter and is used for providing ablation energy for the ablation electrode assembly.

Optionally, the medical device further comprises a mapping catheter having a distal end for insertion through the lumen of the tube assembly and into the target lumen, for mapping the target lumen, and for further ablation of the target site in cooperation with the ablation electrode assembly.

Optionally, the ablation energy comprises pulsed electric field energy or radiofrequency energy.

Compared with the prior art, the ablation catheter and the medical device have the advantages that:

the ablation catheter comprises a tube assembly and an ablation electrode assembly; the ablation electrode assembly is of a tube net structure and is arranged at the distal end of the tube assembly, the proximal end of the ablation electrode assembly is connected to the tube assembly, the ablation electrode assembly is configured to be capable of expanding or contracting along the radial direction of the tube assembly, and the ablation electrode assembly comprises at least one ablation part which surrounds a circle along the circumferential direction of the tube assembly. The ablation catheter can be used for performing catheter ablation to treat atrial fibrillation, ablation energy is a pulse electric field for example, during ablation, the ablation electrode assembly can be radially expanded to enable the ablation part to be at least partially abutted against the cavity wall of a target cavity (such as the inner wall of a pulmonary vein), ablation energy is applied to form a circumferentially continuous ablation focus, and therefore disposable integral ablation is carried out, and ablation efficiency is improved.

Further, the tube assembly comprises a tube body and a balloon sleeved on the outer surface of the distal end of the tube body, the ablation electrode assembly is sleeved on the outer surface of the balloon, the proximal end of the ablation electrode assembly is connected with the tube body, and the balloon is used for selectively providing a radially outward supporting force for the ablation electrode assembly. Namely, the ablation electrode assembly is driven to radially expand through the filling expansion of the balloon, or the radial size of the ablation electrode assembly is further adjusted through the filling expansion of the balloon, so that the ablation part is in close contact with the cavity wall of a target lumen, and the situation of poor fitting is avoided.

Still further, the ablation electrode assembly further comprises a non-ablation portion; the material coverage rate of the ablation part is larger than that of the non-ablation part, so that the continuity of the ablation focus can be further improved, and the uniformity of the ablation energy distribution can be improved. And the softness of the ablation part is greater than that of the non-ablation part, so that the ablation part can be more easily yielded to the cavity wall when being attached to the cavity wall of the target cavity, the cavity wall cannot be greatly deformed, and damage to the cavity wall is reduced.

Drawings

The drawings are included to provide a better understanding of the utility model and are not to be construed as unduly limiting the utility model. Wherein:

fig. 1 is a schematic view of the overall structure of an ablation catheter provided in accordance with an embodiment of the utility model;

FIG. 2 is a schematic partial view of an ablation catheter provided in accordance with an embodiment of the utility model, wherein the inner catheter is shielded by a balloon;

FIG. 3 is a schematic partial view of an ablation catheter in accordance with an embodiment of the present invention with a portion of the balloon and ablation electrode assembly removed to show the inner tube, irrigation tube, temperature sensor and position sensor;

fig. 4 is an enlarged schematic view at a of the ablation catheter shown in fig. 3;

FIG. 5 is a partial schematic structural view of an ablation catheter in accordance with one embodiment of the utility model, with the guide tip not shown and the ablation electrode assembly radially expanded to a distal end diameter d;

FIG. 6 is a partial schematic structural view of an ablation catheter in accordance with one embodiment of the utility model, with the guide tip not shown and the ablation electrode assembly radially expanded to a distal end diameter D, D > D;

FIG. 7 is a schematic view of an application scenario of an ablation catheter provided in accordance with an embodiment of the present invention, wherein the ablation electrode assembly is radially expanded to form a circumferentially continuous lesion at the ostium of a pulmonary vein;

FIG. 8 is a partial schematic structural view of an ablation catheter in accordance with one embodiment of the utility model, with the balloon radially contracted and the ablation electrode assembly still in a radially expanded state;

fig. 9 is a schematic view of an application scenario of an ablation catheter provided in accordance with an embodiment of the present invention, in which an ablation electrode assembly is radially contracted and an ablation portion is in point/line contact with a lumen wall of a target lumen for point/line ablation;

fig. 10 is a schematic partial structure view of an ablation catheter provided in accordance with a second embodiment of the utility model.

[ reference numerals are described below ]:

10-ablation catheter, 100-tube assembly, 110-tube body, 111-inner tube, 112-outer tube, 113-guide tip, 120-balloon, 200-ablation electrode assembly, 201-ablation portion, 201 a-first ablation portion, 201 b-second ablation portion, 202-metal rod, 203-reinforcing rib, 210-first portion, 220-second portion, 221-first connection portion, 222-second connection portion, 221 a-connecting rod, 222-second connection portion;

300-monitoring electrode assembly, 310-first electrode, 320-second electrode;

400-perfusion tube;

510-temperature sensor, 520-positioning sensor;

600-handle assembly, 610-handle body, 620-bending control mechanism, 630-driving mechanism, 640-first joint, 650-second joint, 660-third joint, 670-fourth joint;

20-a mapping catheter;

30-adjustable bending sheath pipe;

1-target location.

Detailed Description

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

Furthermore, although the following description describes each embodiment as having one or more features, this does not imply that all of the features of any embodiment need be implemented by the inventors at the same time, or that only some or all of the features of different embodiments may be implemented separately. In other words, those skilled in the art can selectively implement some or all of the technical features of any embodiment or selectively implement some or all of the technical features of a plurality of embodiments according to the disclosure of the present invention and according to the design specification or the implementation requirement, thereby increasing the flexibility in implementing the utility model.

As used in this specification, the singular forms "a", "an" and "the" include plural referents, and the plural forms "a plurality" includes more than two referents unless the content clearly dictates otherwise. As used in this specification, the term "or" is generally employed in its sense including "and/or" unless the content clearly dictates otherwise, and the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either fixedly connected, detachably connected, or integrally connected. Either mechanically or electrically. Either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

Herein, the terms "proximal" and "distal" are relative orientations, relative positions, and directions of elements or actions with respect to each other from the perspective of a clinician using a medical device, and although "proximal" and "distal" are not intended to be limiting, the term "proximal" generally refers to the end of the medical device that is closer to the clinician during normal operation, and the term "distal" generally refers to the end of the medical device that is first introduced into a patient.

To further clarify the objects, advantages and features of the present invention, a more particular description of the utility model will be rendered by reference to the appended drawings. It is to be noted that the drawings are in a very simplified form and are not to precise scale, which is merely for the purpose of facilitating and distinctly claiming the embodiments of the present invention. The same or similar reference numbers in the drawings identify the same or similar elements.

< example one >

Fig. 1 is a schematic view showing an overall structure of an ablation catheter 10 provided in the present embodiment, and fig. 2 and 3 are schematic views showing a partial structure of the ablation catheter 10. As shown in fig. 1-3, the illustrated ablation catheter 10 includes a tube assembly 100 and an ablation electrode assembly 200. The ablation electrode assembly 200 is a tube mesh structure and is disposed at the distal end of the tube assembly 100, the proximal end of the ablation electrode assembly 200 is connected to the tube assembly 100, and the ablation electrode assembly 200 is configured to be expanded or contracted in the radial direction of the tube assembly 100, the ablation electrode assembly 200 includes at least one ablation part 201, and the ablation part 201 is wound around one turn in the circumferential direction of the tube assembly 100. The ablation portion 201 refers to a portion of the ablation electrode assembly 200 for releasing ablation energy to the outside, and the "outside" refers to a region outside the ablation electrode assembly 200, such as a target location on a target lumen as mentioned later. The ablation catheter 10 is used for performing catheter ablation to treat atrial fibrillation, and during ablation, the ablation electrode assembly 200 can be radially expanded to enable the ablation part 201 to at least partially abut against a target position 1 (as labeled in fig. 7) on a target lumen, so that the ablation part 201 can apply ablation energy to the target position 1 and form a circle of continuous ablation spots on the target lumen to perform one-time integral ablation, and the ablation efficiency is improved. Here, the target lumen is, for example, a pulmonary vein, and the target site 1 may be a section of a cavity wall at the opening of the pulmonary vein (i.e., the target site has a certain axial length). The ablative energy is, for example, a pulsed electric field or radiofrequency energy. The ablation electrode assembly 200 can be shaped such that the diameter increases and then decreases proximally and distally when the ablation electrode assembly 200 is radially expanded, such as an ellipsoid, sphere, etc.

Optionally, as shown in fig. 2 and 3, the ablation electrode assembly 200 includes a first portion 210 and a second portion 220 that are axially connected, wherein a proximal end of the first portion 210 is connected to the tube assembly 100. The first portion 210 includes a conductive member (not shown) and an insulating layer, and the conductive member may be made of metal. The surface of the conductive member is also provided with the insulating layer (not shown), which preferably can withstand a high voltage of 1000V. The conductive member is also used to connect to an external host (not shown) via a wire or other conductive structure and receive ablation energy provided by the host. The second portion 220 is at least partially configured to be electrically conductive and includes at least one ablation portion 201, one ablation portion 201 electrically connected to the electrically conductive member of the first portion 210 to receive ablation energy delivered by the first portion 210. Here, the ablation portion 201 electrically connected to the conductive member may be integrally formed with the conductive member, and it is easily understood that the ablation portion 201 is conductive. In this embodiment, the second portion 220 is entirely conductive and integrally formed with the ablation portion 201, for example, the second portion 220 is entirely made of metal.

The area of the electrode ablation assembly 200 where ablation energy cannot be applied to the outside is referred to herein as a non-ablated portion, that is, in this embodiment, the non-ablated portion includes the area where the first portion 210 is located. Preferably, the material coverage of the second portion 220 is greater than the material coverage of the first portion 210. The advantage of this is that the area of the void of the ablation portion 201 is smaller, when the ablation portion 201 forms a circumferentially arranged ablation focus at the target position, the continuity of the ablation focus is better, the distribution of the ablation energy is more uniform, and at the same time, the softness of the second portion 220 is greater than that of the first portion 210, so that the radial support force generated by the ablation portion 201 is smaller, and it is easier to yield to the wall of the target lumen, so that the tissue deformation at the target position is smaller, and the damage is smaller.

Preferably, the conductive member of the first portion 210 may be integrally formed with the second portion 220. For example, the conductive member may be integrally woven with the second portion 220 by a wire, or the conductive member may be cut from the same metal tube as the second portion 220. When the conductive member and the second portion 220 are cut and formed by a metal tube, as shown in fig. 4, the metal tube is cut into a plurality of metal rods 202 and reinforcing ribs 203, and two adjacent metal rods 202 are smoothly and transitionally connected by the reinforcing ribs 203 to reduce stress concentration at the connection.

Further, referring to fig. 2, the ablation catheter 10 further includes a monitoring electrode assembly 300, where the monitoring electrode assembly 300 is partially disposed on the ablation portion 201 (i.e., the second portion 220) and is configured to monitor impedance information of a target location, and the impedance information can be used to determine whether the ablation portion 201 is closely attached to the target location. Optionally, the monitoring electrode assembly 300 includes a first electrode 310 and a second electrode 320, the first electrode 310 is one and disposed on the tube assembly 100, the second electrode 320 is plural, the second electrodes 320 are disposed on the ablation portion 201 and spaced apart from each other in the circumferential direction of the ablation electrode assembly 200, and each second electrode 320 forms a loop with the first electrode 310 and collects impedance information of the target location.

Optionally, in the embodiment, the number of the second electrodes 320 is 3-8, and in the axial direction of the tube assembly 100, the distance from each second electrode 320 to the distal end of the ablation part 201 is 1/3-2/3 of the axial length of the ablation part 201, and optionally, the second electrodes 320 can be micro-electrodes.

With continued reference to fig. 2 in conjunction with fig. 3, in the present embodiment, the ablation electrode assembly 200 is self-expanding. Here, the ablation electrode assembly 200 is self-expanding in that at least a portion of the material of the ablation electrode assembly 200, such as a shape memory alloy, is resilient, the ablation electrode assembly 200 is pre-shaped in a radially expanded state such that when the ablation electrode assembly 200 is subjected to a radially compressive force, it contracts and stores an elastic potential energy in a radial direction of the tube assembly 100, and when the radially compressive force is removed, the ablation electrode assembly 200 releases the elastic potential energy and expands in the radial direction.

The tube assembly 100 also preferably includes a tube body 110 and a balloon 120 that is fitted over the distal outer surface of the tube body 110. The ablation electrode assembly 200 is fitted over the outer surface of the balloon 120, and the proximal end of the ablation electrode assembly 200 is connected to the tube body 110. When the balloon 120 is inflated and expanded, the outer surface of the balloon 120 may be attached to the inner surface of the ablation electrode assembly 200, and the balloon 120 may further selectively apply a radially outward supporting force to the ablation electrode assembly 200, so as to radially support the ablation electrode assembly 200, prevent the ablation electrode assembly 200 from collapsing under the extrusion of the cavity wall of the target lumen, and simultaneously prevent the second electrode 320 from being poorly attached to the target location, which may result in failure to acquire effective impedance information. Moreover, in some cases, the radial support force may further radially expand the ablation electrode assembly 200 to accommodate the larger diameter of the target lumen, for example, when the ablation electrode assembly 200 is self-expanding and has a distal end with a diameter D (as shown in fig. 5), the balloon 120 is inflated and applies a radial support force to the ablation electrode assembly 200 and the ablation electrode assembly 200 is further expanded to a distal end of the ablation electrode assembly 200 with a larger diameter D (as shown in fig. 6). It will be appreciated that when the balloon 120 is deflated and the ablation electrode assembly 200 is expanded or incompletely expanded, the outer surface of the balloon 120 is separated from the inner surface of the ablation electrode assembly 200 such that there is no interaction force between the two.

In more detail, the tube body 110 comprises an inner tube 111, an outer tube 112 and a guide head 113, wherein the outer tube 112 is sleeved outside the inner tube 111 and can also move relative to the inner tube 111 in the axial direction. The first electrode 310 is disposed on the outer tube 112. The guide head 113 is connected to the distal end of the inner tube 111, and the guide head 113 is communicated with the inner tube 111. The balloon 120 is sleeved on the outer surface of the distal end of the inner tube 111, the distal end of the balloon 120 is connected with the outer surface of the guide head 113 in a sealing manner, the proximal end of the balloon 120 is connected with the distal end of the outer tube 112 in a sealing manner, so that the space between the balloon 120 and the inner tube 111 is used for containing the fluid, and the gap between the outer surface of the inner tube 111 and the inner surface of the outer tube 112 can form a fluid outlet channel.

It is noted that when the ablation electrode assembly 200 is self-expanding, the balloon 120 is not required and may be omitted. Alternatively, when the tube assembly 100 includes the balloon 120, the ablation electrode assembly 200 may not be self-expanding, i.e., when the ablation electrode assembly 200 is fully radially expanded by the radially outward support force provided by the balloon 120.

In addition, the distal end of the ablation electrode assembly 200 may be collapsed and fixedly attached to the introducer 113 (not shown in fig. 1-6). Alternatively, the distal end of the ablation electrode assembly 200 is a free end and is not connected to other components, as shown in fig. 1 to 3, 5 and 6, so that the distal end of the ablation electrode assembly 200 is an open end, and the diameter of the open end becomes larger as the ablation electrode assembly 200 expands, and such a structure can enable the diameter of the distal end of the ablation electrode assembly 200 to have a larger expansion space, thereby better adapting to target lumens with different diameters.

Further, the ablation catheter 10 further includes an infusion tube 400, the infusion tube 400 may extend along the axial direction of the tube assembly 100, and the distal end of the infusion tube 400 is connected to the inner tube 111 by winding or any other suitable manner, the infusion tube 400 is further communicated with the inner cavity of the balloon 120, the inner cavity of the infusion tube 400 forms an introduction channel of a fluid, which may be an inflating agent or a cooling agent, for infusing the fluid into the balloon 120.

Optionally, the ablation catheter 10 further includes sensor assemblies including, but not limited to, a temperature sensor 510 and a positioning sensor 520. The temperature sensor 510 and the positioning sensor 520 are both disposed on the inner tube 111 and located in a region where the balloon 120 is located, wherein the temperature sensor 510 is configured to obtain temperature information of a fluid in the balloon 120, and the positioning sensor 520 is configured to obtain position information of the balloon 120. The positioning sensor 520 is, for example, a magnetic positioning sensor. In other embodiments, the temperature sensor 510 may be further disposed under the second electrode 320 for monitoring the temperature of the tissue at the target location, so that the ablation process can be monitored in real time, and the ablation safety can be improved.

Those skilled in the art will appreciate that the ablation catheter 10 further includes a handle assembly 600, the handle assembly 600 being attached to the proximal end of the tube assembly 100. The handle assembly 600 comprises a handle body 610, wherein a bending control mechanism 620 is arranged on the handle body 610, the bending control mechanism 620 is connected with the distal end of the tube assembly 100 through a pull wire (not shown in the figure), and controls the bending of the distal end of the tube assembly 100 by tightening the pull wire or controls the straightening of the distal end of the tube assembly 100 by loosening the pull wire. In addition, the handle body 610 is further provided with a driving mechanism 630, a first joint 640, a second joint 650, a third joint 660, and a fourth joint 670. The driving mechanism 630 is used for driving the outer tube 112 to move axially relative to the inner tube 111, and further, can be used for adjusting the diameter and length of the balloon 120 and controlling the expansion and contraction of the balloon 120. The distal end of the first connector 640 is connected to the proximal end of the infusion tube 400, and the proximal end of the first connector 640 is used for connecting to an external fluid source. The second connector 650 is in communication with the lumen of the inner tube 111 for passing a mapping catheter 20 (shown in fig. 7). The distal end of the third connector 660 is connected to the monitoring electrode assembly 300 and the sensor assembly to transmit at least one of impedance information, temperature information, and position information. The distal end of the fourth connector 670 is connected to the ablation electrode assembly 200, and the proximal end of the fourth connector 670 is adapted to be connected to the host computer.

Fig. 7 shows a schematic view of a catheter ablation procedure giving pulmonary vein isolation for treatment of atrial fibrillation performed with the ablation catheter 10.

In operation, an adjustable curved sheath (not shown in FIG. 7) is first introduced into the pulmonary vein ostium. The ablation catheter 10 is then delivered along the adjustable bending sheath to allow the ablation electrode assembly 200 at the distal end of the ablation catheter 10 to reach the pulmonary veins via the left atrium, while the distal bending of the tube assembly 100 is controlled by the bending control mechanism 620 to adapt to the opening direction of the pulmonary veins. The adjustable curved sheath is then withdrawn and the ablation electrode assembly 200 is released, causing the ablation electrode assembly 200 to expand radially and also perfuse the perfusion tube 400 with a fluid, which may include a contrast agent, through the first connector 640. The fluid is infused into the inner cavity of the balloon 120 through the infusion tube 400, so that the balloon 120 is inflated and provides a radial supporting force to the ablation electrode assembly 200, so that the ablation part 201 of the ablation electrode assembly 200 and the second electrode 320 on the ablation part 201 are attached to the pulmonary vein opening, and whether the ablation part 201 is attached tightly is judged according to the impedance information collected by the monitoring electrode assembly 300. The fourth connector 670 is then connected to the host machine and ablation energy is provided to the ablation electrode assembly 200 by the host machine for ablation. The ablation energy can be pulsed electric field or radio frequency energy, and in an alternative implementation, the pulsed electric field can be used as ablation energy during the initial period of ablation, and the radio frequency energy can be used as ablation energy during the later period of ablation to perform radio frequency ablation. In the rf ablation, since the ablation electrode assembly 200 is a mesh structure, the ablation part 201 has a large surface area, so that the current density is low, and it is not easy to damage healthy tissue due to overheating, and in addition, the temperature of the fluid in the balloon 120 can be monitored by the temperature sensor 510 to indirectly monitor the temperature of the pulmonary vein wall, and when the temperature is high, the perfusion tube 400 is used to perfuse the fluid with low temperature into the balloon 120 for cooling, so as to understand that the excessive fluid in the balloon 120 can be discharged from the balloon 120 through the gap between the inner tube 111 and the outer tube 112, and the balloon 120 is prevented from being excessively ruptured due to the fluid in the balloon 120.

It should be noted that, in an actual process, the user also inserts a mapping catheter 20 into a pulmonary vein along the inner cavity of the inner tube 111, on one hand, the mapping catheter 20 can perform a ring-lung mapping to determine whether ablation is complete, and on the other hand, the electrodes on the mapping catheter 20 and the ablation electrode assembly 200 can also be used as the positive electrode and the negative electrode respectively to perform bipolar discharge or perform a discharge mode of a single-bipolar combination, so as to achieve the purposes of thoroughly isolating an electrical signal and improving an ablation effect.

It should be noted that after the circumferential circle of the pulmonary vein is entirely ablated, the user can also perform point ablation or line ablation using the ablation part 201 of the ablation catheter 10 as needed. Specifically, as shown in fig. 8 and 9, when the electrode ablation assembly 200 is in a radially expanded state, the balloon 120 is contracted, the inner tube 111 is controlled to move in a distal-to-proximal direction relative to the outer tube 112, the adjustable curved sheath 30 is pushed in a proximal-to-distal direction, the adjustable curved sheath 30 wraps the proximal end of the ablation electrode assembly 200, a radially inward pressure is applied to the ablation electrode assembly 200, so that the ablation electrode assembly 200 is contracted radially, and then the ablation part 201 can be in point contact or line contact with a target position, so as to perform point ablation or line ablation. The advantage of doing so is that, after circumferential whole ablation, some local positions that are not completely ablated can be directly ablated by using the ablation electrode assembly 200 for point ablation or line ablation, and a single-point ablation instrument does not need to be replaced, thereby reducing the operation trouble and the operation risk.

Further, the present embodiment also provides a medical device, which includes the main machine and the ablation catheter 10 of the present embodiment, wherein the main machine is connected to the ablation catheter 10 and is configured to provide ablation energy, such as a pulsed electric field or radio frequency energy, to the ablation electrode assembly 200.

Further, the medical device also includes a mapping catheter 20, the distal end of which is used to pass through the lumen of the tube assembly 100 (specifically the lumen of the inner body 111) and into the target lumen for mapping the target lumen and also for ablating the target site in conjunction with the ablation electrode assembly 200.

< example two >

Fig. 10 is a partial schematic structural view of the ablation catheter 10 provided in the present embodiment, which is different from the first embodiment mainly in the structure of the ablation electrode assembly 200. In detail, the second portion 220 includes two ablation portions 201 and one first connection portion 221. The two ablation portions 201 are arranged at intervals along the axial direction of the tube assembly 100 and are referred to as a first ablation portion 201a and a second ablation portion 201b, respectively, and the first ablation portion 201a is located on the proximal side of the second ablation portion 201 b. The distal end of the first ablation portion 201a is connected to the proximal end of the second ablation portion 201b through the first connection portion 221, and the proximal end of the first ablation portion 201a is electrically connected to the conductive member of the first portion 210 to receive the ablation energy transmitted by the first portion 210. An electrically conductive structure (not shown) such as a wire is connected to the second ablation portion 201b, and the proximal end of the wire is used to connect to the host via the fourth connector 670, so as to transmit the ablation energy provided by the host to the second ablation portion 201 b. The first connection portion 221 may include a plurality of connection bars 221a, each of the connection bars 221a being configured to have an insulation property to electrically isolate the first ablation portion 201a from the second ablation portion 201 b.

Alternatively, in the axial direction of the ablation catheter 10, the lengths of the first ablation part 201a and the second ablation part 201b may be 2mm to 5mm, the length of the first connection part 221 is 3mm to 8mm, and it is further preferable that the distance between the center of the first connection part 221 and the center of the ablation electrode assembly 200 is 0mm to 8mm, so as to ensure effective electrical isolation between the first ablation part 201a and the second ablation part 201b and enable the two ablation parts 201 to abut against the target position.

The distal end of the second portion 220 may be free (i.e., not connected to other components) such that the distal end of the ablation electrode assembly 200 is open-ended. Or the second portion 220 may further include a second connecting portion 222, a proximal end of the second connecting portion 222 is connected to a distal end of the second ablation portion 201b, and a distal end of the second connecting portion 222 is fixedly connected to the guide head 113. The second connection portion 222 may include a core structure, which is preferably integrally formed with the second ablation portion 201b, and an insulating layer is provided on a surface of the core structure. In operation, the first ablation part 201a and the second ablation part 201b can be used as a positive electrode and a negative electrode respectively for bipolar discharge.

In this embodiment, the material coverage of the two ablation portions 201 is greater than that of a non-ablation portion, which includes the areas where the first portion 210, the first connection portion 221, and the second connection portion 222 are located. And the softness of the two ablation portions 201 is greater than the softness of the non-ablation portions. In addition, 3 to 8 second electrodes 320 can be arranged on each ablation part 201.

Further, the embodiment of the present invention further provides a medical device, which includes the ablation catheter 10 and the host described in this embodiment. Preferably, the medical device may further include the mapping catheter 20.

Although the present invention is disclosed above, it is not limited thereto. Various modifications and alterations of this invention may be made by those skilled in the art without departing from the spirit and scope of this invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims (23)

1. An ablation catheter comprising a tube assembly and an ablation electrode assembly; the ablation electrode assembly is of a tube net structure and is arranged at the distal end of the tube assembly, the proximal end of the ablation electrode assembly is connected to the tube assembly, the ablation electrode assembly is configured to be capable of expanding or contracting along the radial direction of the tube assembly, and the ablation electrode assembly comprises at least one ablation part which surrounds a circle along the circumferential direction of the tube assembly.

2. The ablation catheter of claim 1, wherein the ablation electrode assembly is made of a material having self-expanding properties and is pre-shaped to a radially expanded state.

3. The ablation catheter of claim 1, wherein the tube assembly comprises a tube body and a balloon mounted on an outer surface of a distal end of the tube body, the ablation electrode assembly being mounted on an outer surface of the balloon, and a proximal end of the ablation electrode assembly being coupled to the tube body; the balloon is adapted to abut an inner surface of the ablation electrode assembly when expanded and to provide a radially outward supporting force to the ablation electrode assembly.

4. The ablation catheter of claim 1, wherein the ablation electrode assembly further comprises a non-ablative portion; the material coverage of the ablation portion is greater than the material coverage of the non-ablation portion.

5. The ablation catheter of claim 1, wherein the ablation electrode assembly further comprises a non-ablative portion; the softness of the ablation portion is greater than the softness of the non-ablation portion.

6. The ablation catheter of claim 1, wherein the ablation portion is configured to at least partially abut a target site; the ablation catheter further includes a monitoring electrode assembly disposed at least partially on an outer surface of the ablation portion and configured to monitor whether the ablation portion is in close proximity to the target location.

7. The ablation catheter of claim 6, wherein said monitoring electrode assembly includes a first electrode and a plurality of second electrodes, one of said first electrodes being connected to said tube assembly, and a plurality of said second electrodes being disposed in said ablation portion and being arranged circumferentially of said ablation electrode assembly, said first and second electrodes forming a circuit therebetween.

8. The ablation catheter of claim 7, wherein the second electrode is spaced from the distal end of the ablation portion by a distance 1/3-2/3 of the axial length of the ablation portion in the axial direction of the tube assembly.

9. The ablation catheter of claim 1, wherein the ablation electrode assembly includes first and second axially connected portions, a proximal end of the first portion being connected to the tube assembly; the first part comprises a conductive component and an insulating layer, the conductive component is used for being connected with an external host to receive ablation energy provided by the host, and the insulating layer is arranged on the surface of the conductive component; at least part of the structure of the second portion is configured to be electrically conductive and includes at least one of the ablation portions, wherein one of the ablation portions is electrically connected to the electrically conductive member of the first portion to receive ablation energy delivered by the electrically conductive member.

10. The ablation catheter of claim 9, wherein said second portion integrally forms said ablation portion.

11. The ablation catheter of claim 9, wherein said second portion includes two of said ablation portions and a first connection portion, said two ablation portions being a first ablation portion and a second ablation portion, respectively, said first and second ablation portions being spaced apart along an axial direction of said tube assembly and connected by said first connection portion; the first ablation part is closer to the first part and is electrically connected with the conductive component of the first part, and the second ablation part is connected with a conductive structure which is used for being connected with an external host and transmitting ablation energy provided by the host to the second ablation part; the first connection portion is configured to have an insulating property.

12. The ablation catheter according to claim 11, wherein the ablation portion has a length of 2mm to 5mm and the first connection portion has a length of 3mm to 8mm in an axial direction of the ablation catheter; and/or the distance between the center of the first connecting part and the center of the ablation electrode assembly is 0-8 mm in the axial direction of the ablation catheter.

13. The ablation catheter of claim 12, wherein said ablation electrode assembly comprises a plurality of metal rods and a plurality of reinforcing ribs, and adjacent two of said metal rods are joined in smooth transition by said reinforcing ribs.

14. The ablation catheter of any of claims 1-13, wherein the tube assembly comprises a tube body and a balloon disposed at a distal end of the tube body, the ablation electrode assembly being sleeved over an outer surface of the balloon, and a proximal end of the ablation electrode assembly being connected to the tube body; the balloon is configured to selectively provide a radially outward supporting force to the ablation electrode assembly.

15. The ablation catheter of claim 14, wherein the ablation catheter has a first operating condition in which the balloon and the ablation electrode assembly are both in an expanded condition and an outer surface of the balloon abuts an inner surface of the ablation electrode assembly to provide the supportive force; in the second operational configuration, the balloon is deflated and the ablation electrode assembly is in an expanded or non-fully expanded state, with the outer surface of the balloon being spaced from the inner surface of the ablation electrode assembly.

16. The ablation catheter of claim 15, wherein the tube body comprises an inner tube, an outer tube, and a guide tip, the outer tube being disposed outside the inner tube and being capable of axial relative movement with respect to the inner tube, the guide tip being connected to a distal end of the inner tube and in communication with the inner tube; the balloon is sleeved on the outer surface of the far end of the inner tube body, the far end of the balloon is connected with the outer surface of the guide head in a sealing mode, and the near end of the balloon is connected with the far end of the outer tube body in a sealing mode.

17. The ablation catheter of claim 16, further comprising an infusion tube in communication with the lumen of the balloon and adapted to infuse fluid into the lumen; a gap between the inner and outer tubes is used to vent the fluid from the lumen of the balloon.

18. The ablation catheter of claim 16, further comprising a temperature sensor and/or a position sensor disposed on the inner tube in a region of the balloon.

19. The ablation catheter of claim 16, wherein a distal end of the ablation electrode assembly is coupled to the guide tip.

20. The ablation catheter of claim 1, wherein the distal end of the ablation electrode assembly is an open end, the open end increasing in diameter when the ablation electrode assembly is expanded.

21. A medical device comprising a host and the ablation catheter of any of claims 1-20, the host being connected to the ablation catheter and configured to provide ablation energy to the ablation electrode assembly.

22. The medical device of claim 21, further comprising a mapping catheter having a distal end for insertion through the lumen of the tube assembly and into the target lumen, for mapping the target lumen, and for ablating the target location in conjunction with the ablation electrode assembly.

23. The medical device of claim 21, wherein the ablative energy comprises pulsed electric field energy or radiofrequency energy.

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