CN219742868U

CN219742868U - Ablation catheter and myocardial ablation system with same

Info

Publication number: CN219742868U
Application number: CN202320699044.2U
Authority: CN
Inventors: 丘信炯; 李沙; 张庭超
Original assignee: Hangzhou Nuoqin Medical Instrument Co ltd
Current assignee: Hangzhou Nuoqin Medical Instrument Co ltd
Priority date: 2023-03-31
Filing date: 2023-03-31
Publication date: 2023-09-26
Anticipated expiration: 2033-03-31

Abstract

The application provides an ablation catheter which comprises a catheter body, a balloon and ablation sections, wherein the balloon and the ablation sections are positioned at the far end of the catheter body and are axially arranged at intervals, the ablation sections are positioned at the far side of the balloon, and the outer diameter of the ablation sections is smaller than that of the catheter body; the ablation segment includes a lumen and at least one opening, the lumen in communication with the opening; when the catheter body is positioned in a blood vessel and the balloon is in an expanded state, the balloon is attached to the inner wall of the blood vessel and seals the blood vessel, and the ablation section is used for transmitting ablation energy and delivering perfusion liquid to the outside of the ablation section through the inner cavity and the opening so as to perform perfusion ablation.

Description

Ablation catheter and myocardial ablation system with same

Technical Field

The application relates to the field of medical equipment, in particular to an ablation catheter and a myocardial ablation system with the same.

Background

Hypertrophic cardiomyopathy (Hypertrophic Cardiomyopathy, HCM) is a common autosomal dominant inherited cardiovascular disease that manifests itself primarily as one or more segmental hypertrophy of the Left Ventricle (LV) by methods of treatment primarily including drug therapy, ventricular septal ablation (Surgical septalmyectomy), ventricular septal ablation (Ventricular septal ablation), and the like.

Currently, there are ways to ablate ventricular septum tissue with the help of a septum vessel wall using an ablation catheter. However, the existing ablation catheter has a large volume, and can only ablate the space branch with a larger pipe diameter, but can not enter the space branch with a smaller pipe diameter, namely, can not ablate the space branch. In the prior art, a smaller-sized spring ring or guide wire is adopted to ablate a spacer branch with a smaller pipe diameter, but the contact area between the spring ring or guide wire and the wall of a spacer branch vessel is smaller due to the smaller size, so that the ablation efficiency is low; meanwhile, the spring ring or the guide wire has smaller size, and the temperature rise of the spring ring or the guide wire is too fast during ablation, so that the adjacent spaced branch vessel walls are easy to carbonize and scab, and the ablation effect is poor.

Disclosure of Invention

The utility model aims to provide an ablation catheter and a myocardial ablation system with the same.

In order to solve the technical problems, the utility model provides an ablation catheter, which comprises a catheter body, a balloon and ablation sections, wherein the balloon and the ablation sections are positioned at the distal end of the catheter body and are axially arranged at intervals, the ablation sections are positioned at the distal side of the balloon, and the outer diameter of the ablation sections is smaller than the outer diameter of the catheter body; the ablation segment includes a lumen and at least one opening, the lumen in communication with the opening; when the catheter body is positioned in a blood vessel and the balloon is in an expanded state, the balloon is attached to the inner wall of the blood vessel and seals the blood vessel, and the ablation section is used for transmitting ablation energy and delivering perfusion liquid to the outside of the ablation section through the inner cavity and the opening so as to perform perfusion ablation.

The application also provides a myocardial ablation system, which comprises an ablation catheter, an introducer sheath, an energy generating device, an infusion device and a balloon control device, wherein the ablation catheter is movably arranged in the introducer sheath in a penetrating way, the energy generating device is connected with the ablation catheter, and the energy generating device is used for conveying ablation energy to the ablation section; the balloon control device is connected with the ablation catheter and is used for delivering filler to the inner cavity of the balloon so as to expand the balloon or extracting the filler in the inner cavity of the balloon so as to shrink the balloon; the irrigation device is connected with the ablation catheter, and the irrigation device is used for conveying irrigation liquid to the ablation section.

The ablation catheter of the myocardial ablation system reaches the target position of the interval branch blood vessel through the coronary artery and the anterior descending branch blood vessel under the guidance of the guiding sheath pipe, and then the blood vessel is blocked through the saccule, so that the blood can be prevented from scouring an ablation section during ablation, and the ablation section ablates the adjacent interval tissues by means of the blood vessel wall. An ablation section with smaller outer diameter is arranged at the distal end of the ablation catheter, so that the ablation section can be matched with a spacer with smaller pipe diameter so as to ablate the catheter. Meanwhile, the ablation section conveys perfusion liquid to the wall of the interval branch blood vessel in the process of outputting ablation energy, so that the temperature rise speed of the interval branch blood vessel can be effectively reduced, and carbonization caused by too fast temperature rise is avoided; in addition, the perfusion liquid can also convey ablation energy to a position which cannot be reached by the ablation section, so that the ablation range is increased.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present application, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of a myocardial ablation system in accordance with a first embodiment of the present application;

FIG. 2 is a schematic view of the structure of the ablation catheter of FIG. 1;

FIG. 3 is a schematic view of the distal end balloon of the ablation catheter of FIG. 2 in a fully contracted state;

FIG. 4 is an exploded schematic view of the distal end of the ablation catheter of FIG. 3;

FIG. 5 is a schematic view of the distal end balloon of the ablation catheter of FIG. 3 in a fully expanded state;

FIG. 6 is a cross-sectional view of the distal end of the ablation catheter of FIG. 5;

FIG. 7 is an enlarged view of section I of FIG. 6;

FIG. 8 is an enlarged view of section II of FIG. 6;

FIG. 9 is a schematic view of an ablation catheter distal to an inter-arrival branch vessel;

FIG. 10 is another schematic view of the distal end of the ablation catheter of FIG. 9 within a spaced branch vessel;

FIG. 11 is a schematic view of the distal end of the ablation catheter of FIG. 9 in a fully expanded state;

FIG. 12 is another schematic view of the distal end of the ablation catheter of FIG. 11 within a spaced branch vessel;

FIG. 13 is a schematic view of the structure of the distal end of an ablation catheter of a second embodiment of the application;

FIG. 14 is an enlarged view of section III of FIG. 13;

fig. 15 is an enlarged view of section IV of fig. 13;

FIG. 16 is a schematic view of the structure of the distal end of an ablation catheter in accordance with a third embodiment of the application;

FIG. 17 is a schematic view of the distal end of the ablation catheter of FIG. 16 in a fully expanded state within a spaced branch vessel;

FIG. 18 is a schematic view of the structure of the distal end of an ablation catheter of a fourth embodiment of the application;

FIG. 19 is a schematic view of the distal end of the ablation catheter of FIG. 18 in a fully expanded state within a spaced branch vessel;

FIG. 20 is a schematic diagram of the structure of a myocardial ablation system in accordance with a fifth embodiment of the present application;

FIG. 21 is a schematic view of the structure of an ablation catheter of a sixth embodiment of the application;

fig. 22 is a schematic structural view of an ablation catheter of a seventh embodiment of the application.

Detailed Description

The following description of the embodiments of the present application 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 application, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without any inventive effort, are intended to be within the scope of the application.

The following description of the embodiments refers to the accompanying drawings, which illustrate specific embodiments in which the application may be practiced. Directional terms, such as "top", "bottom", "front", "rear", "left", "right", "inner", "outer", "side", etc., in the present application are merely referring to the directions of the attached drawings, and thus, directional terms are used for better, more clear explanation and understanding of the present application, rather than indicating or implying that the apparatus or element being referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present application.

In the description of the present application, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "disposed on … …" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; may be a mechanical connection; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. In the field of interventional medical devices, the proximal end of the medical device refers to the end closer to the operator, and the distal end of the medical device refers to the end farther from the operator; axial refers to a direction parallel to the line connecting the distal center and the proximal center of the medical instrument; the proximal end of a blood vessel refers to the end closer to the heart and the distal end of a blood vessel refers to the end farther from the heart. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances.

Referring to fig. 1, 2 and 6, the myocardial ablation system 100 provided by the present application includes an ablation catheter 20, an introducer sheath 40, an energy generating device 50, an infusion device 70 and a balloon control device 60. The ablation catheter 20 comprises a catheter body 22, a balloon 23 arranged at the distal end of the catheter body 22 and an ablation section 25, wherein the ablation section 25 is positioned at the distal side of the balloon 23, and the outer diameter of the ablation section 25 is smaller than the outer diameter of the catheter body 22; the ablation segment 25 includes a lumen 252 and at least one opening 251, the lumen 252 being in communication with the opening 251; when the catheter body 22 is positioned in a blood vessel and the balloon 23 is in an expanded state, the balloon 23 is attached to the inner wall of the blood vessel and seals the blood vessel, and the ablation segment 25 is used for transmitting ablation energy and delivering an irrigation liquid to the outside of the ablation segment 25 through the inner cavity and the opening for irrigated ablation. The outer surface of the balloon 23 is provided with a plurality of ablation electrodes 24, and the ablation section 25 can be made of metal materials such as nickel-titanium alloy, platinum-iridium alloy, cobalt-chromium alloy, tantalum, stainless steel, copper and the like, preferably nickel-titanium alloy, so that the ablation section 25 is an ablation electrode as a whole. Specifically, in some embodiments, the ablation segment 25 is a hypotube hollow design, and the outer diameter of the ablation segment is smaller than or equal to the outer diameter of the catheter body 22, and the slit cut by the hypotube may be linear, strip-rope-shaped, or the like, and the slit is used as a channel for communicating the inner cavity of the hypotube with the outer side of the hypotube. The slits are arranged in parallel or in a step shape, the length of the slits is Zhou Chang/4 of the outer circumference of the ablation section 25, the distance between adjacent slits is 0.05 mm-1.00 mm, and the width of the slits is 0.028 mm-0.06 mm. By the arrangement, a plurality of openings 251 are formed in the ablation section 25 along the axial direction, an inner cavity 252 is arranged in the ablation section 25, and the openings 251 are communicated with the inner cavity 252. As shown in fig. 6-7, the catheter body 22 is further provided with an irrigation channel 2205, the irrigation channel 2205 extending axially through the catheter body 22 at a proximal end and a distal end of the catheter body 22, the proximal end of the irrigation channel 2205 being connected to the irrigation device 70 and the distal end thereof being connected to the lumen 252 of the ablation segment 25. Thus, after the infusion device 70 infuses fluid into the ablation catheter 20, fluid may flow out of the opening 251 of the ablation segment 25 through the infusion channel 2205, lumen 252. Furthermore, the ablation segment 25 and the ablation electrode 24 are electrically connected to the energy generating device 50, respectively.

The introducer sheath 40 includes an introducer sheath 42 and a handle 44 attached to the proximal end of the introducer sheath 42; the ablation catheter 20 is movably penetrated into the guiding sheath 42 through the handle 44, and the energy generating device 50 is electrically connected with the ablation catheter 20, and the energy generating device 50 is used for respectively delivering ablation energy to the ablation section 25 and the ablation electrode 24; the infusion device 70 and the balloon control device 60 are respectively connected to the ablation catheter 20, and the balloon control device 60 is used for delivering a filler to the lumen of the balloon 23 to expand the balloon 23 or withdrawing the filler in the lumen of the balloon 23 to deflate the balloon 23. The ablation catheter 20 reaches a target position under the guidance of the guiding sheath 42, namely, the distal end of the catheter body 22 is positioned in a blood vessel, the balloon control device 60 is operated to convey the filler to the inner cavity of the balloon 23 through the catheter body 22 so as to ensure that the balloon 23 is maximally expanded and is in a fully expanded state, at the moment, the ablation electrode 24 is attached to the inner wall of the blood vessel along with the expansion of the balloon 23, and after the balloon 23 seals the blood vessel, the energy generating device 50 respectively conveys energy to the ablation section 25 and the ablation electrode 24, and the ablation section 25 and the ablation electrode 24 ablate the ventricular septum tissues adjacent to the inner wall of the blood vessel through the inner wall of the blood vessel. Wherein the outer diameter of the ablation segment 25 is smaller than the outer diameter of the ablation electrode 24, so that the ablation segment 25 can enter a vessel having a smaller inner diameter. Wherein the outer diameter of the ablation segment 25 is 10% -90% of the outer diameter of the balloon 23 in the fully expanded state, preferably the outer diameter of the ablation segment 25 is 20% -80% of the outer diameter of the balloon 23 in the fully expanded state.

The energy generating device 50 is used to provide ablation energy, including but not limited to radio frequency ablation energy, microwave ablation energy, cryoablation energy, pulsed ablation energy, etc., to the ablation segment 25 and ablation electrode 24 of the ablation catheter 20, with the ablation energy preferably being radio frequency ablation energy. Referring to fig. 3, the balloon 23 is in a completely contracted state in a natural state, and the ablation electrode 24 is attached to the outer wall of the balloon 23 along with the balloon 23 in the completely contracted state, wherein the completely contracted state refers to a state when no filler is in the inner cavity of the balloon 23; when the balloon control device 60 is operated, the balloon 23 is expanded after filling the inner cavity of the balloon 23 through the catheter body 22, until the balloon 23 is in a fully expanded state, the ablation electrode 24 is expanded along with the balloon 23, and the ablation electrode 24 is always attached to the outer wall of the balloon 23, as shown in fig. 2. The balloon control device 60 may also pump away the fluid in the balloon 23 to deflate the balloon 23 until it is in a fully deflated state to facilitate the accommodation of the balloon 23 in the introducer sheath 42. The irrigation device 70 comprises a pump 72 and a liquid source 71, the liquid source 71 being connected to the pump 72, the pump 72 delivering irrigation liquid from the liquid source 71 to the ablation catheter 20. The priming liquid of the liquid source 71 is typically an electrolyte solution, and a mixed solution of 0.9% NaCl solution, 5% glucose solution, heparinized 0.9% NaCl solution, and contrast agent, etc., including but not limited to 0.9% NaCl solution at room temperature, may be used. Meanwhile, in order to better reduce the temperature between the contact interface of the ablation section 25 and the inner wall of the blood vessel during radio frequency discharge, a 0.9% NaCl solution at about 5 ℃ is preferably used, so that the temperature rise speed can be effectively reduced, and the problem that the tissue is carbonized due to too fast temperature rise is avoided.

In use, the guide sheath 42 penetrates through the femoral artery and then enters the aorta, the ablation catheter 20 extends out of the tail end (namely the distal end) of the guide sheath 42 after reaching the target position of the interval branch vessel through the coronary artery and the anterior descending branch vessel under the guidance of the guide wire, and the balloon 23 of the ablation catheter 20 extends out of the guide sheath 42 until the ablation section 25 is positioned near the ventricular septum tissue region to be ablated; at this time, the balloon 23 is in a fully contracted state, and the outer side wall of the balloon 23 is not in contact with the inside wall of the branch blood vessel. The balloon 23 of the ablation catheter 20 is filled with a filler by the balloon control device 60 so that the balloon 23 is expanded from the fully contracted state until the outer side wall of the balloon 23 contacts the inner wall of the spaced branch vessel, at which time the balloon 23 is in the fully expanded state, the ablation electrode 24 is attached to the inner wall of the vessel and the balloon 23 occludes the vessel. At the same time, the ablation segment 25 is also in contact with the inner wall of the vessel at a more distal end with respect to the balloon 23.

The ablation catheter 20 of the myocardial ablation system 100 reaches the target position of the interval branch blood vessel through the coronary artery and the anterior descending branch blood vessel under the guidance of the guide wire, and does not need to penetrate subcutaneous, thoracic, pericardial, myocardial and other tissues, so that the tissues are prevented from being damaged; secondly, the balloon 23 of the ablation catheter 20 is directly inserted into the blood vessel, when the balloon 23 is in a fully expanded state, the ablation electrode 24 is attached to the inner wall of the blood vessel, the energy generating device 50 is operated to transmit energy to the ablation section 25 and the ablation electrode 24 and ablate the compartment tissue adjacent to the inner wall of the blood vessel through the inner wall of the blood vessel, and the compartment tissue can be ablated without puncturing the wall of the blood vessel, so that the safety is good, the operation is simple, and a puncturing point is not required to be selected; in addition, when the balloon 23 is in the fully expanded state, the balloon 23 seals the blood vessel to ensure that the balloon 23 blocks the blood vessel to realize flow interruption, thereby avoiding the reduction of the ablation effect due to the scouring of the ablation segment 25 and the ablation electrode 24 by the blood flow in the blood vessel caused by the clearance between the inner wall of the blood vessel and the balloon 23 during the ablation, and further improving the ablation efficiency of the myocardial ablation system 100. Furthermore, by providing the ablation segment 25, a vessel with a smaller inner diameter can be ablated, increasing the ablatable range of the transcorogenic path. Meanwhile, as the ablation section 25 is communicated with the liquid source 71, the pump 70 provides the perfusion liquid to the ablation section 25 when the ablation section 25 ablates, the perfusion liquid can flow out from the opening 251 of the ablation section 25, the perfusion liquid can effectively reduce the temperature rise speed of the interval branch blood vessel, and carbonization caused by too fast temperature rise is avoided; furthermore, the irrigation fluid can also deliver ablation energy to locations not reached by the ablation segment 25, such as finer blood vessels, increasing the range of ablation and thus achieving irrigated ablation.

As shown in fig. 3-5, the balloon 23 is sleeved on the distal end of the catheter body 22, the balloon 23 includes a first end 231 and a second end 232 at opposite ends thereof, the first end 231 is fixedly connected to the catheter body 22, and the second end 232 is movably connected to the catheter body 22 in a sealing manner along the axial direction; during inflation or deflation of the balloon 23, the second end 232 moves axially along the catheter body 22. Specifically, the catheter body 22 includes an elongated main body 220, a guide head 222 disposed at a distal end of the main body 220, and a limiting portion 224, wherein the limiting portion 224 is disposed at a position of the catheter body 22 near the guide head 222, i.e., the limiting portion 224 is disposed at a position of the distal end of the main body 220 near the guide head 222, and an axial space is provided between the limiting portion 224 and the guide head 222. The balloon 23 is disposed on the catheter body 22 through a first end 231 and a second end 232, wherein the first end 231 is fixedly disposed on the catheter body 22, and the second end 232 is located between the guide head 222 and the limiting portion 224. Specifically, the second end 232 is movably disposed on the catheter body 22 and located between the limiting portion 224 and the guide head 222, and the guide head 222 and the limiting portion 224 are used for limiting the travel of the second end 232 along the axial direction of the catheter body 22. When the balloon 23 is in the fully contracted state, the second end 232 and the guide head 222 are abutted against each other; when the balloon 23 is in the fully expanded state, the second end 232 and the stop 224 abut against each other. During the gradual injection of a filler, such as a liquid, into the lumen of balloon 23 to cause gradual expansion of balloon 23, first end 231 remains stationary relative to main body 220, and second end 232 moves relative to main body 220 on main body 220 from a first position in abutment with guide head 222 in the axial direction of catheter body 22 toward first end 231 to cause gradual expansion of the radial dimension of balloon 23; when the second end 232 of the balloon 23 abuts the stop 224, the radial dimension of the balloon 23 expands to a maximum. At this time, the second end 232 is located at a second position that is closer to the first end 231 than the first position. When the balloon 23 is in the fully expanded state, the filler such as liquid in the lumen of the balloon 23 is withdrawn to gradually deflate the balloon 23 until the balloon 23 is in the fully deflated state; during deflation of the balloon 23, since the first end 231 is fixed relative to the main body 220, the second end 232 will move in the axial direction of the catheter body 22 towards the first position, i.e. the second end 232 will move in the axial direction of the catheter body 22 on the main body 220 towards the guide head 222, when the second end 232 moves to said first position, the balloon 23 is in a fully deflated state, the second end 232 abutting the guide head 222. It will be appreciated that during deflation or inflation of the balloon 23, the second end 232 of the balloon 23 moves along the axial direction of the catheter body 22 between the guide head 222 and the stop 224, i.e., the second end 232 moves along the axial direction of the catheter body 22 between the first position and the second position.

As shown in fig. 1 and 2, the balloon control device 60 in the present embodiment is a syringe, and the syringe is used to fill the lumen of the balloon 23 with a liquid, so that the balloon 23 is expanded until the ablation electrode 24 is attached to the inner wall of the blood vessel and the balloon 23 seals the blood vessel. The syringe is also used to withdraw fluid from the lumen of the balloon 23 to collapse the balloon 23 to a fully collapsed state, thereby facilitating the receipt of the balloon 23 into the introducer sheath 42.

The following illustrates the ablation procedure with the myocardial ablation system 100 using a syringe to provide a filler: after the ablation catheter 20 reaches the target position, the injector feeds the liquid into the catheter injection body 22, the catheter body 22 conveys the liquid to the balloon 23, the balloon 23 is expanded after being injected with the liquid, and the second end 232 moves from the first position to the second position on the catheter body 22 relative to the main body 220 until the outer side wall of the balloon 23 is tightly attached to the inner wall of the spacing branch blood vessel and has a tendency of expanding the inner diameter of the spacing branch blood vessel, and the injector is closed to stop liquid conveying. At this time, the second end 232 is located at the second position, that is, the second end 232 abuts against the limiting portion 224, and the balloon 23 blocks the spacer blood vessel, so that the blood flow in the spacer blood vessel is greatly reduced, or the blood flow of the spacer blood vessel is interrupted; the ablation electrode 24 outside the balloon 23 is closely attached to the inner wall of the septum vessel after the balloon 23 is expanded, and the energy generator 50 supplies ablation energy to the ablation section 25 and the ablation electrode 24 and transmits the ablation energy to myocardial tissue around the septum vessel from inside to outside by means of the inner wall of the septum vessel so as to ablate the myocardial tissue around the septum vessel. Specifically, the ablation energy on the ablation segment 25 and the ablation electrode 24 may cause damage to the septal branch vessel, so that the septal branch vessel is atrophic, the blood flow in the lumen of the septal branch vessel is reduced, and the ventricular septum tissue near the septal branch vessel is atrophic, thereby reducing the ventricular septum tissue thickness, and further enhancing the treatment of HCM. If the balloon 23 is not expanded to block the interval branch blood vessel, the blood flow from the anterior descending branch blood vessel will continuously wash the ablation section 25 and the ablation electrode 24, so that the ablation energy part of the ablation section 25 and the ablation electrode 24 is carried away by the blood flow, resulting in low ablation efficiency; the balloon 23 in the application can expand to block the interval branch blood vessel, can prevent the blood flow from the anterior descending branch blood vessel from scouring the ablation section 25 and the ablation electrode 24, and can avoid the reduction of the ablation effect due to the scouring of the blood flow to the ablation section 25 and the ablation electrode 24, thereby improving the ablation efficiency of the ablation section 25 and the ablation electrode 24. Meanwhile, the ablation section 25 conveys perfusion liquid to the wall of the interval branch blood vessel in the process of outputting ablation energy, so that the temperature rise speed of the interval branch blood vessel can be effectively reduced, and carbonization caused by too fast temperature rise is avoided; the irrigation fluid also delivers ablation energy to locations not reached by the ablation segment 25, such as finer blood vessels, increasing the extent of ablation. In order to avoid damage to the heart caused by overfilling of the blood vessel due to too large perfusion flow of the spacer, the perfusion speed is in the range of 0.1ml/min to 12ml/min, preferably 0.5ml/min to 10ml/min, more preferably 0.6ml/min to 0.9ml/min.

Preferably, the guide head 222 is cone-like, i.e., the outer diameter of the guide head 22 tapers from the proximal end to the distal end; the stop 224 is also conical-like in shape with an outer diameter tapering from the proximal end to the distal end; the second end 232 is a sliding ring having an outer diameter less than or equal to the maximum outer diameter of the limiting portion 224.

As shown in fig. 4 and 5, in the present embodiment, the limiting portion 224 is a limiting ring circumferentially surrounding the outer surface of the main body 220 along the circumference of the catheter body 22, and the maximum outer diameter of the limiting ring is greater than or equal to the outer diameter of the second end 232. In the fully contracted state of balloon 23 of ablation catheter 20, the proximal end of guide head 222 abuts second end 232 of balloon 23, and the outer diameter of the proximal end of guide head 222 is equal to the outer diameter of second end 232, so as to avoid the formation of a step between guide head 222 and second end 232, thereby reducing the risk of thrombus formation from blood flushing the step during entry of ablation catheter 20 into a blood vessel. In the fully expanded state of the balloon 23, the limiting part 224 abuts against the second end 232 of the balloon 23, and the outer diameter of the proximal end of the limiting part 224 is not larger than the outer diameter of the second end 232, so that when the limiting part 224 abuts against the second end 232, a step is formed by partially protruding the second end 232 in the axial direction due to the existence of the limiting part 224, and the risk of thrombus formation caused by blood flushing of the step when the balloon 23 is in the fully expanded state is reduced.

Preferably, the outer diameter of the limiting portion 224 increases gradually from the distal end toward the proximal end, that is, the outer diameter of the end of the limiting portion 224 near the guide head 222 is smaller than the outer diameter of the end of the limiting portion 224 far from the guide head 222.

As shown in fig. 5, balloon 23 further includes an intermediate portion 234 between first end 231 and second end 232, and ablation electrode 24 is disposed on an outer surface of intermediate portion 234. When the balloon 23 is in the fully expanded state, the ablation electrode 24 is in contact with the inner wall of the vessel. The ablation electrode 24 is secured to the outside of the balloon 23 by means including, but not limited to, bonding, welding, crimping, soldering, etc., and in particular, the ablation electrode 24 is secured to the peripheral wall of the intermediate portion 234 and is in electrical communication with the external energy generating device 50 via a wire. Ablation electrode 24 may be formed from, but is not limited to, a nickel-titanium alloy, a platinum-iridium alloy, a cobalt-chromium alloy, tantalum, stainless steel, copper, and the like, preferably a nickel-titanium alloy. The nickel-titanium alloy has high strength, is not easy to break, has biocompatibility and is oxidized in the ablation process to form a compact oxide film, so that a loose and easy-to-drop oxide structure is not generated, and vascular embolism caused by emboli is avoided. The ablation electrode 24 has an inflatable property, and the ablation electrode 24 is disposed outside the balloon 23 in the axial direction of the balloon 23, i.e., the ablation electrode 24 is wound around the outer peripheral wall of the intermediate portion 234. Ablation electrode 24 may take on various shapes, such as linear, helical, mesh, etc.; the mesh structure is preferred because it increases the contact area of the ablation electrode 24 with the interior wall of the blood vessel, and allows ablation of the blood vessel and adjacent myocardial tissue during delivery of ablation energy from the ablation electrode 24 to the interior wall of the blood vessel. The opposite ends of the ablation electrode 24 are folded, one end of the ablation electrode 24 is fixedly connected with the second end 232 of the balloon 23 and can move axially on the catheter body 22 along with the second end 232, and the other end of the ablation electrode 24 is fixedly connected with the first end 231 of the balloon 23.

In this embodiment, the intermediate portion 234 has an equal diameter configuration, and the outer diameter of the intermediate portion 234 is equal to 1.0-1.2 times the inner diameter of the spaced branch vessel when the balloon 23 is in the fully expanded state. In use of the ablation catheter 20, the balloon 23 of the ablation catheter 20 is passed through a coronary artery, an anterior descending branch vessel, to a target site of a septal branch vessel to ablate the inner wall of the septal branch vessel 305. The following chart shows that when the first septal branch vessel S1 is ablated, if the inner diameter of the first septal branch vessel S1 is 1.3mm, the minimum value of the outer diameter D1 of the corresponding earth capsule 23 in the fully expanded state is 1.3mm, and the maximum value of the balloon 23 should be 1.3×1.2=1.56 mm; that is, the minimum outer diameter of the intermediate portion 234 in the fully expanded state is 1.3mm, and the maximum outer diameter of the intermediate portion 234 should be 1.3x1.2=1.56 mm. When the second spaced branch vessel S2 is ablated, if the inner diameter of the second spaced branch vessel S2 at this time is 1.2mm, the minimum value of the outer diameter D1 of the corresponding earth capsule 23 in the fully expanded state is 1.2mm, and the maximum value of the balloon 23 should be 1.32×1.2=1.44 mm; that is, the minimum outer diameter of the intermediate portion 234 in the fully expanded state is 1.2mm, and the maximum outer diameter of the intermediate portion 234 should be 1.32×1.2=1.44 mm. When the third spaced branch vessel S3 is ablated, if the inner diameter of the third spaced branch vessel S3 at this time is 1.15mm, the minimum value of the outer diameter D1 of the corresponding earth capsule 23 in the fully expanded state is 1.15mm, and the maximum value of the balloon 23 should be 1.15×1.2=1.38 mm; that is, the minimum outer diameter of the intermediate portion 234 in the fully expanded state is 1.15mm, and the maximum outer diameter of the intermediate portion 234 should be 1.15×1.2=1.38 mm.

	Average inner diameter/mm	Midpoint inside diameter/mm	Coronary length/mm
				Anterior descending vessel LAD1	3.46±0.89	3.50±0.85	22.20±9.08
First spaced branch vessel S1	1.26±0.36	1.22±0.28	14.84±9.00
				Second spaced branch vessel S2	1.17±0.30	1.16±0.26	15.22±9.35
Third spaced branch vessel S3	1.15±0.25	1.14±0.19	14.52±12.69

As shown in fig. 6, the balloon 23 further includes a first transition portion 235 and a second transition portion 236, the intermediate portion 234 is connected between the first transition portion 235 and the second transition portion 236, the first transition portion 235 is connected between the first end 231 and the intermediate portion 234, and the second transition portion 236 is connected between the second end 232 and the intermediate portion 234. Both the first transition 235 and the second transition 236 smoothly transition from the ablation catheter 20 to the intermediate portion 234, i.e., the first transition 235 smoothly transitions from the first end 231 to the intermediate portion 234 and the second transition 236 smoothly transitions from the second end 232 to the intermediate portion 234. The outer diameter of the intermediate portion 234 is constant from the proximal end to the distal end when the balloon 23 is in the fully expanded state, such that the intermediate portion 234 can correspondingly adapt to the inner diameter of the spacer branch vessel, and the outer diameter of the intermediate portion 234 in the fully expanded state should be greater than or equal to the average inner diameter of the spacer branch vessel. Preferably, the outer diameter D1 of the intermediate portion 234 in the fully expanded state should be 1.0-1.2 times the average inner diameter D2 of the spaced branch vessels, i.e., D2. Ltoreq.D1.ltoreq.1.2d2; more preferably 1.01×d2.ltoreq.d1.ltoreq.1.1×d2, specifically, D1 is preferably 1.02×d2, 1.03×d2, 1.05×d2. The outer diameter D1 of the intermediate portion 234 in the fully expanded state is set to be not smaller than the average inner diameter D2 of the septum, because the lumen of the septum is a lumen of a similar diameter, some portions are larger than the average inner diameter thereof, and some portions are smaller than the average inner diameter thereof, in order to ensure that the intermediate portion 234 can occlude the septum after expansion to avoid the blood flow from the anterior descending vessel from flushing the ablation electrode 24 and the ablation segment 25, the outer diameter D1 of the intermediate portion 234 in the fully expanded state is set to be not smaller than the average inner diameter D2 of the septum, i.e., the outer diameter D1 of the intermediate portion 234 in the fully expanded state is larger than the inner diameter of the smaller inner diameter portion of the septum, so that the balloon 23 can be ensured to occlude the smaller inner diameter portion of the septum. The first transition portion 235 and the second transition portion 236 are both inflated, and when the balloon 23 is in the fully expanded state, the outer diameter of the first transition portion 235 gradually increases from the first end 231 to the intermediate portion 234, and the outer diameter of the second transition portion 236 gradually increases from the second end 232 to the intermediate portion 234.

As shown in fig. 5 and 6, one end of the ablation electrode 24 extends over the first transition portion 235 to connect to the first end 231, and an insulating layer 237 is provided on the outer surface of the first transition portion 235; the other end of the ablation electrode 24 extends over the second transition 236 to connect the second end 232, the outer surface of the second transition 236 being provided with an insulating layer 237. The insulating layer 237 is made of an insulating material, and the insulating layer 237 can be expanded or contracted following the balloon 23. The insulating material comprises, but is not limited to, high polymer materials such as polyether ether ketone, polyimide and the like. The ablation electrode 24 is covered by an insulating layer 237 over the first transition 235 and the second transition 236 of the balloon 23 from contact with the spaced branch vessel wall; that is, the intermediate portion 234 is the active segment of the ablation electrode 24, and the first transition portion 235 and the second transition portion 236 are the inactive segments of the ablation electrode 24. Providing the insulating layer 237 on the outer surfaces of the first transition portion 235 and the second transition portion 236, respectively, can avoid that during the process of flushing the ablation electrode 24 with blood flow, rf energy is carried to the non-target ablation region by the blood flow, reduce energy loss and avoid damage to the non-target ablation region.

As shown in fig. 6 and 7, the catheter body 22 is provided with a first channel 2201, the first channel 2201 has a first opening 2203, the first opening 2203 communicates with the inner cavity of the balloon 23, the first channel 2201 is used for conveying a filler, and the filler is filled into or discharged out of the inner cavity of the balloon 23 through the first channel 2201. Specifically, a syringe delivers liquid to the lumen of balloon 23 through first channel 2201 to expand balloon 23, and the syringe can also draw liquid out of the lumen of the balloon through first channel 2201 to deflate balloon 23. A first end of the first channel 2201 is connected to the syringe and a second, opposite end of the first channel 2201 is disposed in a portion of the ablation catheter 20 corresponding to the balloon 23 such that the lumen of the balloon 23 is in communication with the second end of the first channel 2201. The first opening 2203 is provided at the second end of the first channel 2201, and the angle α between the direction of the opening 2203 and the axial direction of the catheter body 22 is preferably acute, that is to say the first channel 2201 extends from along the axial direction of the catheter body 22 towards the distal direction to away from the axial direction of the catheter body 22 and then towards the proximal direction; preferably, the included angle α ranges from 30 degrees to 80 degrees, such as the included angle α may be, but not limited to, 30 degrees, 40 degrees, 50 degrees, 60 degrees, 70 degrees, 80 degrees, etc.; in this embodiment, the included angle α is 60 degrees; as liquid is injected from opening 2203 into the lumen of balloon 23 through first channel 2201, the liquid enters the lumen of balloon 23 in the direction of opening 2203.

As shown in fig. 6, the middle portion 234 includes a first section 2341 adjacent the first end 231 and a second section 2343 adjacent the second end 232, and the first opening 2203 communicates with the interior cavity of the first section 2341. As the filler is injected into the lumen of balloon 23 from first opening 2203 through first channel 2201, the filler enters the lumen of balloon 23 in the direction of first opening 2203, i.e., the filler reaches first section 2341 of the lumen of balloon 23 before flowing to second section 2343 of the lumen of balloon 23. Thus, as the filler is delivered through the first channel 2201, the filler enters the lumen of the balloon 23 from the first opening 2203 and preferentially fills the first section 2341 of the balloon 23, and then the second section 2343 of the balloon 23 is again filled, such that the first section 2341 expands first and the second section 2343 expands later when the balloon 23 expands. During the process of using the ablation catheter 20, the first section 2341 of the balloon 23 is expanded first to block the proximal end of the corresponding septum vessel, the distal end of the corresponding septum vessel is synchronously contracted and reduced in diameter due to the loss of blood support when the second section 2343 of the balloon 23 is expanded, and when the balloon 23 is attached to the inner wall of the septum vessel 305, the second section 2343 of the balloon 23 is subjected to a larger force than the first section 2341 of the balloon 23, so that the ablation electrode 24 positioned on the outer surface of the second section 2343 of the balloon 23 is in closer contact with the inner wall of the corresponding septum vessel, the ablation energy transfer effect is better, and the ablation efficiency is higher.

As shown in fig. 3 to 6, the outer surface of the catheter body 22 is provided with the developing member 225, and when the balloon 23 is in the fully expanded state, the developing member 225 is located in a forward projection area of the intermediate portion 234 on a plane parallel to the axial direction of the catheter body 22, or a forward projection of one end edge of the intermediate portion 234 on a plane parallel to the axial direction of the catheter body 22 coincides with the developing member 225. By providing the developing member 225 on the catheter body 220 at a portion corresponding to the balloon 23, the operator can easily determine the position of the balloon 23 with the aid of an imaging system such as CT. In this embodiment, two developing members 225 spaced apart from each other are disposed on the outer surface of the catheter body 22, and both developing members 225 are located within the scope of the balloon 23 correspondingly disposed on the catheter body 220; i.e., the developer 225 is positioned between the first end 231 and the second end 232. Further, when the balloon 23 is in the fully expanded state, the balloon 23 includes two shoulders 2342, the two shoulders 2342 being the junctions of opposite ends of the middle portion 234 with the first transition portion 235 and the second transition portion 236, respectively. The two developing elements 225 are disposed between the areas of the catheter body 22 corresponding to the two shoulders 2342 of the balloon 23, i.e. the two developing elements 225 are located between the opposite edges of the catheter body 22 corresponding to the middle portion 234 when the balloon 23 is in the fully expanded state. Since the area between the two shoulders 2342 of the balloon 23 is the working segment of the ablation electrode 24, the ablation working region of the balloon 23 can be marked by disposing the visualization element 225 between the working segment areas of the balloon 23. Preferably, two developing members 225 are respectively disposed on the catheter body 22 and correspond to the two shoulder portions 2342 one by one, that is, when the balloon 23 is in the fully expanded state, the two developing members 225 are respectively aligned with the two shoulder portions 2342, and the orthographic projection of the shoulder portions 2342 on a plane parallel to the axial direction of the catheter body 22 coincides with the developing members 225, that is, the orthographic projections of opposite end edges of the intermediate portion 234 on a plane parallel to the axial direction of the catheter body 22 coincide with the two developing members 225, respectively. By the arrangement, the two developing parts 225 can mark the specific ablation working area of the balloon 23 in the fully expanded state, and an operator can accurately know the effective ablation area of the balloon 23 by observing the two developing parts 225.

The developing member 225 is made of a developing material including, but not limited to, a radiopaque material such as platinum iridium alloy, cobalt chromium alloy, tantalum, etc., preferably platinum iridium alloy. The development member 225 may be, but is not limited to, a development wire, a development point, a development ring, or the like, continuously or intermittently wrapped around the catheter body 22. The developer 225 may be, but is not limited to, embedded, affixed or sleeved on the catheter body 22. In this embodiment, the developing member 225 is a developing ring sleeved on the outer surface of the catheter main body 220, and the developing ring surrounds the catheter main body 22 continuously or at intervals.

In some embodiments, the outer surface of the catheter body 22 is provided with a developing member 225, the developing member 225 being a developing ring which is located in the forward projection area of the intermediate portion 234 on a plane parallel to the axial direction of the catheter body 22 or with which the forward projection of one of the end edges of the intermediate portion 234 on a plane parallel to the axial direction of the catheter body 22 coincides when the balloon 23 is in the fully expanded state. By providing a developing ring on the catheter body 220 at a portion corresponding to the balloon 23, an operator can easily determine the position of the balloon 23 with the aid of an imaging system such as CT. In the fully expanded state of the balloon 23 after inflation, the balloon 23 has two shoulders, i.e. where the outer diameter of the balloon 23 transitions from small to maximum, the developing ring is preferably arranged between the areas of the catheter body 22 corresponding to the two shoulders of the balloon 23, so that the ablation working zone of the balloon 23 can be marked.

In some embodiments, the outer surface of catheter body 22 is provided with three or more visualization elements 225, each of the three visualization elements 225 being located in the forward projection area of intermediate portion 234 on a plane parallel to the axial direction of catheter body 22, or the forward projection of the opposite end edges of intermediate portion 234 on a plane parallel to the axial direction of catheter body 22 coincides with two of the visualization elements 225, the other visualization elements 225 being located in the forward projection area of intermediate portion 234 on the outer surface of catheter body 22, when balloon 23 is in the fully expanded state.

In some embodiments, the developing member 225 is a developing ring slidably disposed over the catheter body 220, the developing ring being coupled to the shoulder 2342 of the balloon 23. When the balloon 23 expands or contracts, the shoulder 2342 can drive the developer 225 to move axially on the catheter body 22, and the specific ablation working region of the balloon 23 is marked by providing two developer rings corresponding to the two shoulder 2342 respectively.

In some embodiments, the visualization element 225 may also be a visualization wire or visualization point provided on the balloon 23 that wraps at least one revolution around the balloon 23 when the balloon 23 is in the fully expanded state. Further, a visualization wire or visualization spot is attached to the intermediate portion 234 of the balloon 23. Preferably, one turn of developing wire or one turn of developing spot is provided on each of the two shoulders 2342 of the balloon 23.

In some embodiments, the developing member 225 is a developing wire that is embedded or affixed to the outer surface of the catheter body 22 for at least one revolution.

In some embodiments, the development member 225 is a development spot continuously or intermittently affixed to the outer surface of the catheter body 22 for at least one revolution, the development spot being affixed to the catheter body 22 by stitching, stamping, hot pressing, taping, or taping.

As shown in fig. 1, 6 and 8, the catheter body 22 is axially provided with a wire 242 and encapsulated with an insulating material. The guidewire 242 may be disposed within a lumen or wall of the catheter body 22 with the distal end of the guidewire 242 extending to the outer wall of the balloon 23 and the distal end of the guidewire 242 being connected to the ablation segment 25, ablation electrode 24, respectively, and the proximal end of the guidewire 242 being connected to the energy generating device 50 such that the ablation segment 25 and ablation electrode 24 are electrically connected to the energy generating device 50 via the guidewire 242. The energy generating device 50 delivers ablation energy to the ablation segment 25 and the ablation electrode 24 via the wire 242 for ablation. Further, a sensor 243 may be provided on the outer surface of the balloon 23, and the sensor 243 is connected to the energy generating device 50 by a wire 242, and the sensor 243 is preferably a temperature sensor and/or a pressure sensor, and the pressure sensor may be, but is not limited to, a piezoresistive pressure sensor, an optical fiber pressure sensor, a piezoelectric pressure sensor, a capacitive pressure sensor, or the like. The temperature sensor can collect the temperature of the current ablation region and feed temperature information back to the energy generating device 50 through the lead 242 so that an operator can know the current ablation condition, and meanwhile, the follow-up ablation energy output can be controlled according to the temperature information. Further, temperature sensors and/or pressure sensors may also be provided within the ablation segment 25 so that the operator is aware of the current ablation situation, while also controlling the subsequent ablation energy output in accordance with the temperature information.

Referring to fig. 1 and fig. 9-12, the myocardial ablation system 100 of the present application operates as follows:

first, under the guidance of an ultrasound/CT imaging system, the catheter 42 is guided by the guide wire 70 through the radial artery or femoral artery, and enters the septum branch vessel 305 through the aorta 301 and the anterior descending branch vessel 303.

In a second step, after the introducer sheath 42 has been advanced into the spacer 305, the ablation catheter 20 is delivered to the target site along the lumen of the introducer sheath 42.

Third, the balloon 23 is filled with a filler such as a liquid by operating the balloon control device 60, and the filler fills the balloon 23 to expand the balloon 23 until the outer side of the balloon 23 is closely attached to the inner wall of the spaced branch vessel 305. Since the outer surface of the balloon 23 is provided with the ablation electrode 24, the ablation electrode 24 will follow the expansion of the outer side of the balloon 23 until the ablation electrode 24 is in close contact with the inner wall of the spaced branch vessel 305.

Fourth, the external energy generating device 50 and the irrigation device 70 are activated, so that the energy generating device 50 delivers ablation energy to the ablation segment 25 and the ablation electrode 24 and ablates the target tissue through the inner wall of the spaced branch vessel 305, and the irrigation device 70 delivers irrigation liquid to the ablation segment 25.

And fifthly, judging the size of the ablation range through an ultrasonic/CT imaging system and the like, and stopping the output of the energy generating device 50 and the perfusion device 70 when the ablation range reaches the expected size. The balloon control device 60 applies negative pressure to the balloon 23 to pump away the filler material of the lumen of the balloon 23 until the balloon 23 is in a fully contracted state, and then withdraws the balloon 23 into the lumen of the introducer sheath 42.

Sixth, the position of the guiding sheath 42 in the interval branch vessel 305 is adjusted, and the operations from the second step to the fifth step are repeated until all the region selection and ablation are completed.

After ablation is completed, a continuous plurality of ablation zones a and B will remain on the hypertrophic ventricular septum, preferably the plurality of ablation zones a and B can be joined together to form an elongated or circular-like continuous ablation zone.

It should be noted that the ablation electrode 24 on the balloon 23 is not necessary, and that it is also possible to remove the ablation electrode 24 and ablate the spaced branch vessel 305 only with the ablation segment 25, and in this embodiment, the balloon 23 only serves to occlude the vessel and avoid flushing the ablation segment 25 with blood.

Referring to fig. 13-15, the structure of the ablation catheter 20a according to the second embodiment of the application is similar to that of the ablation catheter 20 according to the first embodiment, except that: in the second embodiment, compared to the ablation catheter 20 having more than one channel along the axial direction, specifically, the catheter body 22 of the ablation catheter 20a is provided with a first channel 2201 and a second channel 2206 along the axial direction in parallel, the first channel 2201 has a first opening 2203, the second channel 2206 has a second opening 2207, the middle portion 234 includes a first section 2341 near the first end 231 and a second section 2343 near the second end 232, the first opening 2203 is communicated with the inner cavity of the first section 2341, and the second opening 2207 is communicated with the inner cavity of the second section 2343; the first channel 2201 is used to fill the lumen of the balloon 23 with a filler, i.e., the balloon control device 60 delivers the filler to the lumen of the balloon 23 through the first channel 2201; the second channel 2206 is used to expel the filler from the lumen of the balloon 23, i.e. the balloon control device 60 withdraws the filler from the lumen of the balloon 23 through the second channel 2206. In this embodiment, the first channel 2201 and the second channel 2206 are parallel to each other, the first opening 2203 of the first channel 2201 communicates with the inner cavity of the first section 2341, and the second opening 2207 of the second channel 2206 communicates with the inner cavity of the second section 2343.

One end of the first channel 2201 and one end of the second channel 2206 are both connected with the filler device, and the other end of the first channel 2201 and the other end of the second channel 2206 are both disposed in the ablation catheter 20a at a portion corresponding to the balloon 23, so that the balloon 23 is in communication with the first channel 2201 and the second channel 2206. Specifically, the first opening 2203 is disposed in the first channel 2201 at a position corresponding to the first section 2341 of the balloon 23 in the ablation catheter 20a, and an included angle α is formed between an opening direction of the first opening 2203 and an axial direction of the ablation catheter 20a, wherein the included angle α is preferably an acute angle, that is, the first channel 2201 extends from the axial direction to a direction away from the axial direction and toward the proximal direction, and when the filler is injected from the first opening 2203 through the first channel 2201, the filler enters the balloon 23 along the direction of the first opening 2203, that is, the liquid reaches the first section 2341 of the balloon 23 first, and then flows to the second section 2343 of the balloon 23. Thus, as a filler device, such as a syringe, delivers fluid through first passageway 2201, the fluid enters balloon 23 from first opening 2203 and preferentially fills the lumen of first segment 2341 of balloon 23, and then removes the lumen of second segment 2343 of balloon 23, and first segment 2341 expands and second segment 2343 expands upon inflation of balloon 23. The angle α is preferably 20 ° -80 °, more preferably 60 °.

The second opening 2207 of the second channel 2206 is disposed at the position of the ablation catheter 20a corresponding to the second section 2343 of the balloon 23, and an included angle β is formed between the opening direction of the second opening 2207 and the axial direction of the ablation catheter 20a, and the included angle β may be an obtuse angle, a right angle or an acute angle. When the included angle β is obtuse, the second opening 2207 is directed towards the second transition 236 and the filler device, such as a syringe, during aspiration of the filler in the balloon 23, the filler is collected towards the second transition 236 and then discharged from the second opening 2207. Accordingly, the filler material located in the lumen of the second section 2343 of balloon 23 is preferentially expelled from the second opening 2207, and then the filler material located in the lumen of the first section 2341 of balloon 23 is subsequently expelled from the second opening 2207. When the included angle β is a right angle, the second opening 2207 is perpendicular to the axial direction of the catheter body 22, that is, the opening direction of the second opening 2207 is consistent with the radial direction of the catheter body 22, and during the process of sucking the filler in the balloon 23, the filler is collected in the second section 2343 and then discharged from the second opening 2207, so that the filler in the inner cavity of the second section 2343 of the balloon 23 is preferentially discharged from the second opening 2207, and then the filler in the inner cavity of the first section 2341 of the balloon 23 is subsequently discharged from the second opening 2207. When the included angle β is acute, the second opening 2207 faces the first segment 2341, and the filler device gathers toward the second segment 2343 and then discharges the filler from the second opening 2207 during the process of sucking the filler in the balloon 23, so that the filler in the cavity of the second segment 2343 of the balloon 23 is preferentially discharged from the second opening 2207, and then the filler in the cavity of the first segment 2341 of the balloon 23 is subsequently discharged from the second opening 2207; the filler device preferentially expels filler material located in the lumen of the second section 2343 of the balloon 23 from the second opening 2207 as the filler material in the balloon 23 is aspirated, and then subsequently expels filler material located in the lumen of the first section 2341 of the balloon 23 from the second opening 2207. Thus, upon inflation of balloon 23 of ablation catheter 20a, first section 2341 of balloon 23 is inflated and second section 2343 of balloon 23 is inflated; when the balloon 23 of the ablation catheter 20a is contracted, the second section 2343 of the balloon 23 is contracted first, and the first section 2341 of the balloon 23 is contracted later. Since the inner wall of the vessel tends to adhere to the surface of the balloon 23 after the end of ablation, if the first and second sections 2341 and 2343 of the balloon 23 are contracted simultaneously, a larger area of tear will be created on the inner wall of the vessel to cause a larger amount of bleeding in the myocardium. Through the contraction process of the balloon 23, the balloon 23 is sequentially separated from the inner wall of the corresponding interval branch blood vessel, so that massive myocardial hemorrhage caused by large-area tearing of the inner wall of the blood vessel due to simultaneous contraction of the first section 2341 and the second section 2343 of the balloon 23 is avoided, and the damage to the inner wall of the blood vessel is reduced.

In some embodiments, the second opening 2207 may also be provided at the ablation catheter 20a corresponding to the first section 2341 of the balloon 23, so that fluid within the lumen of the first section 2341 of the balloon 23 is preferentially expelled from the second opening 2207 as the filler device aspirates fluid within the balloon 23, and then fluid within the second section 2343 of the balloon 23 is subsequently expelled from the second opening 2207. Thus, when balloon 23 is inflated, first segment 2341 thereof expands first and second segment 2343 expands later; when the balloon 23 is deflated, its first segment 2341 is deflated and its second segment 2343 is deflated. Similarly, through the above-mentioned contraction process, the balloon 23 and the inner wall of the corresponding interval branch blood vessel can be sequentially separated, so that massive myocardial hemorrhage caused by large-area tearing of the inner wall of the blood vessel due to simultaneous contraction of the first section 2341 and the second section 2343 of the balloon 23 is avoided, and damage to the inner wall of the blood vessel is reduced.

Referring to fig. 6, 16 and 17, the structure of an ablation catheter 20b according to a third embodiment of the application is similar to that of the ablation catheter 20 of the first embodiment, except that: the shape of the balloon 23a of the ablation catheter 20b of the third embodiment in the fully expanded state is different from the shape of the balloon 23 of the ablation catheter 20 in the first embodiment in the fully expanded state, specifically, when the balloon 23a is in the fully expanded state, the intermediate portion 234 is in a variable diameter structure, and the outer diameter of the intermediate portion 234 near the first end 231 is larger than the outer diameter of the intermediate portion 234 away from the first end 231. Specifically, the outer diameter of the first section 2341 of the intermediate portion 234 of the balloon 23a adjacent to the first transition portion 235 is greater than the outer diameter of the second section 2343 of the intermediate portion 234 of the balloon 23a adjacent to the second transition portion 236, i.e., the proximal radial dimension of the intermediate portion 234 of the balloon 23a is greater than the distal radial dimension of the intermediate portion 234 of the balloon 23 a.

During normal blood flow through the spacer branch vessel 305, the inner diameter of the proximal end 3051 of the spacer branch vessel 305 is enlarged by the blood flow; after the spacer branch vessel 305 is occluded by the balloon 23a, the blood flow through the distal end 3053 of the spacer branch vessel 305 is greatly reduced, thereby causing the portion of the spacer branch vessel 305 to contract and the inner diameter to decrease, so that the inner diameter of the spacer branch vessel 305 has a tendency that the proximal end 3051 is large and the distal end 3053 is small. If the balloon with the equal diameter of the middle portion 234 is adopted, the acting force of the second section 2343 of the middle portion 234 on the inner wall of the spacing branch vessel 305 will be greater than the acting force of the first section 2341 of the middle portion 234 on the inner wall of the spacing branch vessel 305, so that the second section 2343 of the balloon has a high probability of bonding with the inner wall of the spacing branch vessel 305 in the process of ablation, when the balloon contracts after the ablation is finished, the second section 2343 of the balloon may drive and tear the bonded inner wall of the spacing branch vessel 305, and the tearing part is also increased along with the increase of the contraction amplitude, thereby causing myocardial hemorrhage. In this embodiment, the outer diameter of the second section 2343 of the balloon 23a is smaller than the outer diameter of the first section 2341 of the balloon 23a, and at this time, the acting force applied to the inner wall of the spacing branch vessel 305 by the second section 2343 of the variable-diameter balloon 23a will be smaller than the acting force applied to the inner wall of the spacing branch vessel 305 by the second section 2343 of the constant-diameter balloon 23. The diameter of the second section 2343 of the variable diameter balloon 23a is smaller when expanded than when the second section 2343 of the constant diameter balloon is expanded, so that the stroke of the balloon 23a is smaller when contracted than that of the constant diameter balloon, and the damage to the inner wall of the spacer branch vessel 305 when the balloon 23a is contracted is reduced, thereby avoiding myocardial hemorrhage. Thus, during use, the first section 2341 of the balloon 23a is expanded to block the proximal end 3051 of the corresponding spacer vessel 305, the distal end 3053 of the corresponding spacer vessel 305 is also contracted and reduced in diameter simultaneously when the second section 2343 of the balloon 23a is expanded, and the diameter of the second section 2343 of the balloon 23a is smaller than the diameter of the first section 2341 of the balloon 23a when the balloon 23a is attached to the spacer vessel 305, so that the balloon 23a forms a structure with a larger diameter of the proximal end 3051 and a smaller diameter of the distal end 3053, and therefore, the contraction stroke of the second section 2343 of the balloon 23a is smaller than that of the first section 2341 when the balloon 23a is contracted, thereby reducing the damage to the inner wall of the spacer vessel 305 when the balloon 23a is contracted, and avoiding myocardial bleeding. When deflation of the balloon 23a is desired, the filler device draws filler from within the balloon 23a through the first passageway to deflate the balloon 23 a.

Preferably, the outer diameter of the intermediate portion 234 of the balloon 23a varies to be gradually smaller. Specifically, the outer diameter of the first and second sections 2341, 2343 of the variable-diameter balloon 23a in the fully expanded state is gradually reduced from the proximal end to the distal end, and the first and second sections 2341, 2343 are smoothly transitioned. Thus, when the balloon 23a is in the fully expanded state, the average outer diameter of the first section 2341 is greater than the average outer diameter of the second section 2343.

Preferably, when the balloon 23a is in the fully expanded state, the average outer diameter D3 of the first segment 2341 is equal to 1.0-1.2 times the average inner diameter D2 of the spacing branch vessel 305, i.e. d2.ltoreq.d3.ltoreq.1.2.d2, more preferably 1.01.ltoreq.d2.ltoreq.d3.ltoreq.1.1.d2, in particular D3 is preferably 1.02.d2, 1.03.d2, 1.05.d2, etc.; the average outer diameter D4 of the second segment 2343 is equal to 0.7-1.0 times the average inner diameter D2 of the spacing branch vessel 305, i.e. 0.7 x d2.ltoreq.d4.ltoreq.d2, more preferably 0.8 x d2.ltoreq.d4.ltoreq.0.99 x d2, in particular D4 is preferably 0.95 x D2, 0.9 x D2, 0.85 x D2, etc.

Referring to fig. 6, 18 and 19, the structure of an ablation catheter 20c according to a fourth embodiment of the application is similar to that of the ablation catheter 20 of the first embodiment, except that: the shape of the balloon 23b of the ablation catheter 20c of the fourth embodiment in the fully expanded state is different from the shape of the balloon 23 of the ablation catheter 20 in the fully expanded state in the first embodiment, specifically, when the balloon 23b is in the fully expanded state, the outer diameter of the intermediate portion 234 is stepwise smaller; that is, the outer diameter of the first section 2341 of the intermediate portion 234 of the balloon 23b near the first transition portion 235 tapers from the proximal end to the distal end, the outer diameter of the second section 2343 of the intermediate portion 234 of the balloon 23b near the second transition portion 236 remains constant from the proximal end to the distal end, and the outer diameter at the intersection of the first section 2341 and the second section 2343 of the balloon 23b is equal to the outer diameter of the second section 2343 of the balloon 23 b. The radial dimension of the proximal end of the first section 2341 of the balloon 23b is greater than the radial dimension of the distal end of the first section 2341 of the balloon 23b, and the radial dimension of the distal end of the first section 2341 of the balloon 23b is equal to the radial dimension of the second section 2343 of the balloon 23 b.

Preferably, when the balloon 23b is in the fully expanded state, the first and second sections 2341, 2343 of the balloon 23b transition smoothly to avoid the risk of thrombus from the step between the first and second sections 2341, 2343. Specifically, when the balloon 23b is in the fully expanded state, the average outer diameter D5 of the first segment 2341 is equal to 1.0-1.2 times the average inner diameter D2 of the spacing branch vessel, i.e., d2.ltoreq.d5.ltoreq.1.2.d2, more preferably 1.01.ltoreq.d5.ltoreq.1.1.d2, specifically, D5 is preferably 1.02.d2, 1.03.d2, 1.05.d2, etc.; the outer diameter D6 of the second segment 2343 is equal to 0.7-1.0 times the inner diameter D2 of the spacer branch, i.e. 0.7 x d2.ltoreq.d6.ltoreq.d2, more preferably 0.8 x d2.ltoreq.d6.ltoreq.0.99 x d2, in particular D6 is preferably 0.95 x D2, 0.9 x D2, 0.85 x D2 etc.

Preferably, the first section 2341 of the balloon 23b extends axially a length greater than or equal to the length of the second section 2343 of the balloon 23 b.

During normal blood flow through the spacer branch vessel 305, the inner diameter of the proximal end 3051 of the spacer branch vessel 305 is enlarged by the blood flow; after the spacer branch vessel 305 is occluded by the balloon 23b, the blood flow through the distal end 3053 of the spacer branch vessel 305 is greatly reduced, thereby causing the portion of the spacer branch vessel 305 to contract and the inner diameter to decrease, so that the inner diameter of the spacer branch vessel 305 has a tendency that the proximal end 3051 is large and the distal end 3053 is small. If the balloon with the equal diameter of the middle portion 234 is adopted, the acting force of the second section 2343 of the middle portion 234 on the inner wall of the spacing branch vessel 305 is larger than the acting force of the first section 2341 of the middle portion 234 on the inner wall of the spacing branch vessel 305, so that the second section 2343 of the balloon 23 has a larger probability of bonding with the inner wall of the spacing branch vessel 305 in the process of ablation, when the balloon 23 is contracted after the ablation is finished, the second section 2343 of the balloon 23 drives and tears the bonded inner wall of the spacing branch vessel 305, and the tearing part is also enlarged along with the increase of the contraction amplitude, thereby causing myocardial hemorrhage. In this embodiment, the outer diameter of the second section 2343 of the balloon 23b is smaller than the outer diameter of the first section 2341 of the balloon 23b, and at this time, the force applied to the inner wall of the septum and branch vessel 305 by the second section 2343 of the balloon 23b will be smaller than the force applied to the inner wall of the septum and branch vessel 305 by the second section 2343 of the balloon 23 with the same diameter. The diameter of the balloon 23b when the second section 2343 is expanded is smaller than the diameter of the balloon 23 when the second section 2343 is expanded, so that the contraction stroke of the balloon 23b is smaller than that of the balloon 23 with equal diameter, and the damage to the inner wall of the spacer branch vessel 305 when the balloon 23b is contracted is reduced, thereby avoiding myocardial hemorrhage. Thus, during use, the first section 2341 of the balloon 23b is expanded to close the proximal end of the corresponding spacer blood vessel 305, the distal end of the corresponding spacer blood vessel 305 is also contracted and reduced in diameter simultaneously when the second section 2343 of the balloon 23b is expanded, and the diameter of the second section 2343 of the balloon 23b is smaller than the diameter of the first section 2341 of the balloon 23b when the balloon 23b is attached to the spacer blood vessel 305, so that the balloon 23b forms a structure with a large proximal end diameter and a small distal end diameter, and the contraction stroke of the second section 2343 of the balloon 23b is smaller than that of the first section 2341 when the balloon 23b is contracted, so that the damage to the inner wall of the spacer blood vessel 305 when the balloon 23b is contracted can be reduced, thereby avoiding myocardial bleeding. When deflation of the balloon 23b is required, the filler device draws filler from within the balloon 23b through the first channel to deflate the balloon 23 b.

In some embodiments, the outer diameter of the first section 2341 of the balloon intermediate portion 234 adjacent the first transition portion 235 remains constant from the proximal end to the distal end, the outer diameter of the second section 2343 of the balloon intermediate portion 234 adjacent the second transition portion 236 tapers from the proximal end to the distal end, and the outer diameter at the intersection of the first section 2341 and the second section 2343 of the balloon is equal to the outer diameter of the first section 2341 of the balloon. The radial dimension of the first section 2341 of the balloon is greater than the radial dimension of the proximal end of the second section 2343 of the balloon. Preferably, when the balloon is in a fully expanded state, the first and second sections 2341, 2343 of the balloon transition smoothly so as to avoid the risk of thrombus from the step between the first and second sections 2341, 2343. Specifically, when the balloon is in the fully expanded state, the outer diameter D7 of the first segment 2341 is equal to 1.0-1.2 times the average inner diameter D2 of the spacer branch vessel, i.e., d2.ltoreq.d7.ltoreq.1.2×d2, more preferably 1.01×d2.ltoreq.d7.ltoreq.1.1×d2, specifically, D7 is preferably 1.02×d2, 1.03×d2, 1.05×d2, etc.; the average outer diameter D8 of the second segment 2343 is equal to 0.7-1.0 times the inner diameter D2 of the spacer branch, i.e. 0.7×d2.ltoreq.d8.ltoreq.d2, more preferably 0.8×d2.ltoreq.d8.ltoreq.0.99×d2, in particular D8 is preferably 0.95×d2, 0.9×d2, 0.85×d2, etc. Preferably, the length of the first balloon section 2341 extending in the axial direction is greater than or equal to the length of the second balloon section 2343 extending in the axial direction.

Referring to fig. 20, a myocardial ablation system 100a according to a fifth embodiment of the present application has a similar structure to that of the myocardial ablation system 100 of the first embodiment, except that: the balloon control device 60a of the myocardial ablation system 100a of the fifth embodiment is different from the balloon control device 60 in the myocardial ablation system 100, specifically, the balloon control device 60a includes a pump 63 and a liquid source 65, and the pump 63 is connected to the ablation catheter 20 and the liquid source 65, respectively. Pump 63 provides liquid from liquid source 65 to ablation catheter 20 to expand the balloon until in a fully expanded state; or pump 63 pumps the liquid from the balloon lumen to deflate the balloon until it is in a fully deflated state. Since the method of operation of the myocardial ablation system 100a is similar to that of the myocardial ablation system 100, the description thereof will not be repeated.

Referring to fig. 21, the structure of an ablation catheter 20d according to a sixth embodiment of the application is similar to that of the ablation catheter 20 of the first embodiment, except that: the ablation section 25a of the ablation catheter 20d is a spring structure, and the spring structure makes the ablation section 25a form a plurality of openings 251a along the axial direction, and a cavity (not shown in the figure) is arranged inside the ablation section 25a, and the openings 251a are communicated with the cavity. After irrigation device 70 infuses fluid into ablation catheter 20d, fluid may flow out of opening 251a of ablation segment 25a through irrigation channel 2205, the lumen. In some embodiments, ablation segment 25a is a round wire spring structure with a wire diameter of 0.05mm to 0.1mm and a pitch of 0.05mm to 1.5mm. In some embodiments, the ablation segment 25a is a flat wire spring structure, the cross section of the wire diameter of the flat wire spring along the axial direction is rectangular, the width and length of the rectangular are both 0.1 mm-0.2 mm, the length and width of the rectangular can be equal or unequal, and the pitch of the flat wire spring is 0.12 mm-0.25 mm. Since the structure and operation of the ablation catheter 20d are similar to those of the first embodiment, the details are not repeated here.

Referring to fig. 22, the structure of an ablation catheter 20e according to a seventh embodiment of the application is similar to that of the ablation catheter 20d according to the sixth embodiment, except that: the ablation section 25b of the ablation catheter 20e is a multi-strand torsion tube structure, and the multi-strand torsion tube structure makes the ablation section 25b form a plurality of openings 251b along the axial direction, and a cavity (not shown in the figure) is arranged inside the ablation section 25b, and the openings 251b are communicated with the cavity. After irrigation device 70 infuses fluid into ablation catheter 20e, fluid may flow out of opening 251b of ablation segment 25b through irrigation channel 2205, the lumen. In some embodiments, the ablation section 25b is a round wire torsion tube structure, the round wire torsion tube has a wire diameter of 0.05mm to 0.15mm, and the number of strands of the round wire torsion tube is 15 to 50; the pitch of the round wire torsion tube is 1 mm-7 mm. In some embodiments, ablation segment 25b is a flat wire multi-strand torsion tube structure with a strand number of 12-18 strands, preferably 14 strands; the cross section of the wire diameter of the flat wire torsion tube along the axial direction is rectangular, the cross section width and the length value interval of the wire diameter of the flat wire torsion tube are both 0.1 mm-0.2 mm, and the length and the width of the rectangle can be equal or unequal; the pitch of the flat wire torsion tube is 2 mm-10 mm. Since the structure and operation of the ablation catheter 20e are similar to those of the sixth embodiment, the details are not repeated here.

While the foregoing is directed to the preferred embodiments of the present application, it will be appreciated by those skilled in the art that changes and modifications may be made without departing from the principles of the application, such changes and modifications are also intended to be within the scope of the application.

Claims

1. An ablation catheter is characterized by comprising a catheter body, a balloon positioned at the distal end of the catheter body and arranged at intervals along the axial direction, and an ablation section, wherein the ablation section is positioned at the distal side of the balloon, and the outer diameter of the ablation section is smaller than that of the catheter body; the ablation segment includes a lumen and at least one opening, the lumen in communication with the opening;

when the catheter body is positioned in a blood vessel and the balloon is in an expanded state, the balloon is attached to the inner wall of the blood vessel and seals the blood vessel, and the ablation section is used for transmitting ablation energy and delivering perfusion liquid to the outside of the ablation section through the inner cavity and the opening so as to perform perfusion ablation.

2. The ablation catheter of claim 1, wherein the perfusion fluid has a perfusion flow rate of 0.1ml/min-12ml/min.

3. The ablation catheter of claim 1, wherein the ablation segment is a hypotube structure, a spring structure, or a multi-strand torsion tube structure.

4. The ablation catheter of claim 1, wherein the balloon is sleeved on the catheter body, the balloon including a first end and a second end at opposite ends thereof, the first end being fixedly connected to the catheter body, the second end being movably connected to the catheter body, the second end being axially movable along the catheter body during expansion or contraction of the balloon.

5. The ablation catheter of claim 4, wherein the balloon further comprises an ablation electrode and an intermediate portion between the first end and the second end, the ablation electrode conforming to an outer surface of the intermediate portion, the ablation electrode being expandable or contractible with the balloon, the ablation electrode conforming to an inner wall of the vessel when the balloon is in a fully expanded state.

6. The ablation catheter of claim 5, wherein the intermediate portion is of constant diameter configuration when the balloon is in a fully expanded state, the intermediate portion having an outer diameter equal to 1.0-1.2 times the average inner diameter of the vessel.

7. The ablation catheter of claim 5, wherein the intermediate portion is of a variable diameter configuration when the balloon is in a fully expanded state, the intermediate portion having a larger outer diameter proximate the first end than the intermediate portion distal the first end.

8. The ablation catheter of claim 7, wherein the intermediate portion comprises a first section proximate the first end and a second section proximate the second end, the first section having an average outer diameter that is greater than an average outer diameter of the second section when the balloon is in a fully expanded state.

9. The ablation catheter of claim 8, wherein the average outer diameter of the first section is 1.0-1.2 times the average inner diameter of the blood vessel and the average outer diameter of the second section is equal to 0.7-1.0 times the inner diameter of the blood vessel.

10. The ablation catheter of claim 5, wherein the balloon further comprises a first transition portion connected between the first end and the intermediate portion, one end of the ablation electrode extending over the first transition portion to connect the first end, an outer surface of the first transition portion being provided with an insulating layer; the balloon further comprises a second transition part, the second transition part is connected between the second end and the middle part, the other end of the ablation electrode extends to be connected with the second end on the second transition part, and an insulating layer is arranged on the outer surface of the second transition part.

11. The ablation catheter of claim 5, wherein the catheter body is provided with a first channel having a first opening that communicates with the lumen of the balloon, the first channel being for delivering a filler that fills or exits the lumen of the balloon through the first channel.

12. The ablation catheter of claim 11, wherein the intermediate portion comprises a first section proximate the first end and a second section proximate the second end, the first opening communicating with the lumen of the first section.

13. The ablation catheter of claim 5, wherein the catheter body is provided with a first channel having a first opening and a second channel having a second opening, the intermediate portion comprising a first section proximate the first end and a second section proximate the second end, the first opening communicating with the lumen of the first section and the second opening communicating with the lumen of the first section or the second section; the first channel is used for filling the inner cavity of the balloon with filler, and the second channel is used for discharging the filler of the inner cavity of the balloon.

14. The ablation catheter of any of claims 12-13, wherein an angle between an opening direction of the first opening and an axial direction of the catheter body is acute.

15. The ablation catheter of claim 4, wherein the catheter body comprises a guide head and a limit portion, the guide head is disposed at a distal end of the catheter body, the limit portion is disposed on the catheter body near the guide head, an axial space is provided between the guide head and the limit portion, and the second end is disposed between the guide head and the limit portion; when the balloon is in a completely contracted state, the second end and the guide head are propped against each other; when the balloon is in a fully expanded state, the second end and the limiting part are mutually propped against each other.

16. The ablation catheter of claim 15, wherein the guide head is cone-like and the second end is a slip ring having an outer diameter less than or equal to a maximum outer diameter of the cone-like.

17. The ablation catheter of claim 16, wherein the stop is a stop ring circumferentially surrounding the catheter body on an outer surface of the catheter body, the stop ring having a maximum outer diameter greater than or equal to an outer diameter of the slip ring.

18. A myocardial ablation system comprising an ablation catheter as defined in any one of claims 1-17, an introducer sheath, an energy generating device, an infusion device and a balloon control device, the ablation catheter movably penetrating the introducer sheath, the energy generating device being connected to the ablation catheter, the energy generating device being configured to deliver ablation energy to the ablation segment; the balloon filler device is connected with the ablation catheter and is used for delivering filler to the inner cavity of the balloon so as to expand the balloon or extracting the filler in the inner cavity of the balloon so as to shrink the balloon; the irrigation device is connected with the ablation catheter, and the irrigation device is used for conveying irrigation liquid to the ablation section.