WO2025060844A1 - Ablation catheter, ablation device, and ablation method based on ablation device - Google Patents

Abstract

An ablation catheter, an ablation device, and an ablation method based on the ablation device, relating to the technical field of medical instruments. The ablation catheter comprises a catheter body (10), a flexible expansion body (20), and splines (30); the flexible expansion body (20) is provided at the distal end of the catheter body (10); the flexible expansion body (20) is suitable for being in contact with a pulmonary vein antrum or entry, and upon expansion contact, squeezing out blood between the flexible expansion body and the atrial wall; the splines (30) are arranged on the surface of the flexible expansion body (20) and are connected and fixed to the catheter body (10); each spline (30) is provided with at least one electrode (31); and the electrode (31) is suitable for being electrically connected to an ablation system. The improved ablation catheter structure can cause the energy of an ablation electric field to more concentratedly act on myocardial tissue, reducing the loss and side effects of current in blood, greatly improving the safety and effectiveness of ablation, and achieving wider prospects in the field of arrhythmia treatment.

Description

Ablation catheter, ablation device and ablation method thereof Technical Field

The present invention relates to the technical field of medical devices, and in particular to an ablation catheter, an ablation device and an ablation method thereof.

Background Art

In some cases, the ablation catheter includes a catheter and an electrode assembly, wherein the electrode assembly is disposed at the distal end of the catheter, and the electrode assembly includes a plurality of electrodes disposed on the catheter branch. When an electric pulse passes through the electrode, an electric field forms an ablation electric field on the surface of the electrode from the positive electrode to the negative electrode. The energy emission is dispersed around the electrode.

However, during the procedure, this ablation catheter is placed close to the pulmonary vein orifice in the left atrium for ablation, and there is a large amount of blood in the left atrium. For all electrodes, some electrodes are in contact with atrial tissue, and some electrodes are surrounded by blood. Since the conductivity of blood is higher than that of atrial tissue, the discharge between the positive and negative electrodes will form arcs and bubbles, which can cause most of the energy of the pulsed electric field to be lost through the blood. At the same time, the bubbles and microthrombi generated in the blood can cause so-called invisible cerebral infarction. Among all the electrodes, only a small number of electrodes are attached to the atrial wall, and the electric field on the surface of the electrodes acts on the myocardium, resulting in ablation lesions, which are used for atrial fibrillation ablation. Since blood exists in the ablation environment, it affects the discharge of the electrodes, resulting in large current losses and side effects in the blood of traditional ablation catheters.

Summary of the invention

The main purpose of the present invention is to provide an ablation catheter, an ablation device and an ablation method thereof, which are intended to squeeze out the blood in the ablation environment and avoid blood interference, so as to reduce the loss and side effects of electric current in the blood and enhance the safety and effectiveness of ablation.

To achieve the above-mentioned purpose, the present invention proposes an ablation catheter, comprising: a catheter body, a flexible expansion body and a spline, wherein the flexible expansion body is arranged at the distal end of the catheter body, and the flexible expansion body is suitable for contacting the vestibule or entrance of the pulmonary vein, and squeezing out the blood between it and the atrial wall after expansion contact; the spline is arranged on the surface of the flexible expansion body and is connected and fixed to the catheter body, and at least one electrode is provided on the spline, and the electrode is suitable for being electrically connected to the ablation system.

In one embodiment, the flexible expansion body is a spherical capsule, a cylindrical capsule or a special-shaped film; the flexible expansion body is provided with a filling cavity and a plurality of liquid injection micropores connected to the filling cavity, the catheter body is provided with a liquid inlet channel connected to the filling cavity, the liquid inlet end of the liquid inlet channel is suitable for passing liquid, the liquid is used to fill the flexible expansion body, the liquid is physiological saline for cooling local tissue, A mixture of anticoagulant liquid and contrast agent used for imaging.

In one embodiment, when the liquid pressure in the filling chamber is less than the target pressure value, the plurality of liquid injection micropores do not allow liquid to pass through; when the liquid pressure in the filling chamber is greater than or equal to the target pressure value, the flexible expansion body expands until the aperture of the liquid injection micropore reaches the target aperture to allow liquid to be ejected; and/or the plurality of liquid injection micropores are radially arranged on the distal surface of the flexible expansion body.

In one embodiment, the catheter body includes an outer tube and an inner tube arranged in the outer tube; the inner tube and the outer tube form the liquid inlet channel, the liquid inlet channel extends into the filling cavity and is provided with a liquid outlet hole connected to the filling cavity; or the inner tube forms the liquid inlet channel and is provided with a liquid return channel, the distal end of the inner tube extends into the filling cavity and is provided with a liquid outlet hole connected to the liquid inlet channel and a liquid extraction hole connected to the liquid return channel, so that the liquid in the filling cavity circulates.

In one embodiment, the catheter body also includes a middle tube arranged between the inner tube and the outer tube, the inner tube and the middle tube can move relative to each other in the axial direction, the proximal end of the flexible expansion body is connected to the middle tube, the proximal end of the spline is fixed on the proximal end of the flexible expansion body, and the wire of the electrode is arranged between the outer tube and the middle tube.

In one embodiment, the ablation catheter also includes a morphology control head, which is fixed on the distal end of the inner tube, and the distal ends of the flexible expander and the spline are fixed in the morphology control head; the morphology control head is used to control the morphology of the flexible expander and the spline; or the distal end of the flexible expander is fixed in the morphology control head; the morphology control head is used to control the morphology of the flexible expander.

In one embodiment, the ablation catheter also includes an operating handle, which is connected to the proximal end of the catheter body; the operating handle includes a handle body and a pushing member movably arranged on the handle body, the pushing member is sleeved on the inner tube, and is used to push the inner tube to move axially relative to the outer tube; the pushing member is provided with a first connector connected to the inner tube, and the first connector is suitable for connecting to a liquid supply device to inject physiological saline into the inner tube to expel air in the tube, thereby preventing surgery from causing air embolism to the human body.

In one embodiment, a connection seat connected to the catheter body is provided in the handle body, and a wire cavity and a liquid inlet and outlet are provided in the connection seat. The liquid inlet and outlet are connected to the liquid inlet channel and are suitable for passing liquid.

In one embodiment, a sealing ring and a sealing ring stopper are provided in the connecting seat, the sealing ring is sleeved on the inner tube, and the sealing ring stopper is provided on one side of the sealing ring and sleeved on the inner tube to block the sealing ring.

In one embodiment, a T-shaped connecting portion is provided at the distal end of the spline, a connecting sleeve is provided in the shape control head, the connecting sleeve is provided with a groove matching the T-shaped connecting portion, and the spline and the shape control head are fixed by hot melting or bonding.

In one embodiment, the spline includes a plurality of flexible electrode substrates, each of which is provided with at least one flexible electrode, and the plurality of flexible electrode substrates are arranged at intervals along the circumference of the flexible expansion body.

In one embodiment, the spline includes an integrated flexible substrate having multiple branch substrates, each of the branch substrates is provided with at least one electrode, and the electrode is a flexible electrode; wherein the proximal end of the integrated flexible substrate is curled into a connecting portion arranged in a cylindrical shape, the connecting portion is inserted into the catheter body, and a plurality of welding points are provided on the connecting portion, and the plurality of welding points are connected and conducted with the flexible electrodes one by one and are suitable for welding with the wire connected to the ablation system; and/or the distal end of the integrated flexible substrate is arranged in a ring shape and is attached to the surface of the flexible expansion body.

In one embodiment, the plurality of branch substrates are of different lengths.

In one embodiment, the splines are bonded to the surface of the flexible expansion body; and/or the splines are wrapped on the surface of the flexible expansion body via a film ring.

To achieve the above object, the present invention further provides an ablation device, comprising:

An ablation catheter, wherein the ablation catheter is the ablation catheter as described above; the ablation catheter comprises a catheter body, a flexible expansion body, a spline and an ablation system, wherein the flexible expansion body is arranged at the distal end of the catheter body, the flexible expansion body is suitable for contacting the pulmonary vein vestibule or entrance, and expands after contact to squeeze out the blood between it and the atrial wall; the spline is arranged on the surface of the flexible expansion body and is connected and fixed to the catheter body, and at least one electrode is provided on the spline, and the electrode is suitable for being electrically connected to the ablation system; the ablation system is connected to the electrode of the ablation catheter through a wire, and the ablation system is used to control the discharge of the electrode; the ablation system comprises a host computer, a controller, a power module, and an impedance detection module , a function switching module and a mapping module, the host computer is electrically connected to the controller, the power supply module and the impedance detection module are electrically connected to the controller respectively, and the function switching module is electrically connected to the impedance detection module; the impedance detection module is used to test the impedance between the electrode and the reference electrode; the reference electrode is a specific electrode located at the proximal end of the ablation catheter and in the blood, or the reference electrode is any one of the electrodes on the spline; the function switching module is used to control the working state of the mapping module according to the control signal of the controller, and select energy output, impedance detection or mapping; the mapping module is used to collect, receive or input potential information, and output mapping electrical signals.

To achieve the above-mentioned purpose, the present invention also proposes an ablation method, based on the ablation device as described above, the ablation method includes the following steps: after the ablation catheter contacts the vestibule or entrance of the pulmonary vein, testing the impedance between each electrode and the reference electrode to obtain an impedance detection value; judging the application state of each electrode according to the impedance detection value; closing the electrode in a blood-surrounded state, and controlling the discharge of the electrode in contact with the vestibule or entrance of the pulmonary vein.

In the technical solution of the present invention, the ablation catheter includes a catheter body, a flexible expansion body and a spline; the flexible expansion body is arranged at the distal end of the catheter body, and the flexible expansion body is suitable for contacting the vestibule or entrance of the pulmonary vein, and expands after contact to squeeze out the blood between it and the atrial wall; the spline is arranged on the surface of the flexible expansion body and is connected and fixed to the catheter body, and at least one electrode is arranged on the spline, and the electrode is suitable for being electrically connected to the ablation system. In this way, by adopting the ablation catheter of the above structure, when the ablation catheter contacts the vestibule or entrance of the pulmonary vein, the expanded flexible expansion body squeezes out the blood between it and the atrial wall, and the ablation electrode is between the insulating flexible expansion body and the conductive atrial wall. The electrode is more closely attached, which can make the electrode apply the electric field to the atrial tissue more concentratedly, thereby effectively reducing the loss of current in the blood and side effects, and greatly enhancing the safety and effectiveness of the ablation technique.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

FIG1 is a schematic structural diagram of an ablation catheter according to an embodiment of the present invention;

FIG2 is a front view of an embodiment of an ablation catheter of the present invention;

FIG3 is a schematic structural diagram of an inner tube and a spline in an embodiment of an ablation catheter of the present invention;

FIG4 is a front view of an inner tube and a spline in an embodiment of an ablation catheter of the present invention;

FIG5 is a cross-sectional view of the inner tube injection hole of an embodiment of the ablation catheter of the present invention;

FIG6 is a cross-sectional view of the inner tube at the liquid extraction hole in one embodiment of the ablation catheter of the present invention;

FIG7 is a schematic diagram of a first electrode arrangement in an embodiment of an ablation catheter of the present invention;

FIG8 is a schematic diagram of a second electrode arrangement in an embodiment of an ablation catheter of the present invention;

FIG9 is a cross-sectional view of a catheter body in an embodiment of an ablation catheter of the present invention;

FIG10 is a schematic diagram of a branch structure of a first split spline in an embodiment of an ablation catheter of the present invention;

FIG11 is a schematic diagram of a branch structure of a second split spline in an embodiment of an ablation catheter of the present invention;

FIG12 is a schematic structural diagram of a connection sleeve of a shape control head in an embodiment of an ablation catheter of the present invention;

FIG13 is a front view of an ablation catheter according to an embodiment of the present invention;

FIG14 is a schematic diagram of the arrangement of electrodes and liquid injection microholes in an embodiment of an ablation catheter of the present invention;

FIG15 is a schematic structural diagram of an ablation catheter according to an embodiment of the present invention;

FIG16 is a front view of a first integrated spline in an embodiment of an ablation catheter of the present invention;

FIG17 is a side view of a first integrated spline in an embodiment of an ablation catheter of the present invention;

FIG18 is a front view of a second integrated spline in an embodiment of an ablation catheter of the present invention;

FIG19 is a side view of a second integrated spline in an embodiment of an ablation catheter of the present invention;

FIG20 is a cross-sectional view of a catheter body and a flexible expansion body in an embodiment of an ablation catheter of the present invention;

FIG21 is a front view of an ablation catheter according to an embodiment of the present invention;

FIG22 is a cross-sectional view of an embodiment of an ablation catheter of the present invention;

FIG23 is a cross-sectional view of a catheter body in an embodiment of an ablation catheter of the present invention;

FIG24 is a morphological diagram of a flexible expandable body in a first filling state in an embodiment of an ablation catheter of the present invention;

FIG25 is a morphological diagram of the flexible expansion body in an embodiment of the ablation catheter of the present invention when it is in a second filling state;

FIG26 is a schematic diagram of bidirectional bending adjustment of an ablation catheter according to an embodiment of the present invention;

FIG27 is a schematic diagram of the structure of an operating handle in an embodiment of an ablation catheter of the present invention;

FIG28 is a cross-sectional view of an operating handle in an embodiment of an ablation catheter of the present invention;

FIG29 is a transverse cross-sectional view of a connecting seat in an embodiment of an ablation catheter of the present invention;

FIG30 is a longitudinal cross-sectional view of a connecting seat in an embodiment of an ablation catheter of the present invention;

FIG31 is a structural block diagram of an ablation system in an embodiment of an ablation device of the present invention;

FIG32 is a schematic flow chart of an ablation method according to an embodiment of the present invention;

FIG33 is a detailed flow chart of an ablation method according to an embodiment of the ablation device of the present invention;

FIG. 34 is a detailed flow chart of another embodiment of the ablation method of the ablation device of the present invention.

Description of Figure Numbers:
10. catheter body; 20. flexible expansion body; 30. spline; 31. electrode; 20a. liquid injection microhole;
10a, liquid inlet channel; 10b, liquid return channel; 11, inner tube; 12, middle tube; 13, outer tube; 14, shape control head; 15, bending wire drawing; 11a, liquid outlet;
11b, liquid extraction hole; 301, T-shaped connecting portion; 140, connecting sleeve; 141, groove; 311, flexible electrode substrate; 312, flexible electrode;
313, wire; 321, integrated flexible substrate; 322, connecting portion; 323, ring end; 324, thin
Membrane ring; 40, operating handle; 41, handle body; 42, pushing member; 421, first connector; 422, second connector; 411, connecting seat; 411a, wire cavity; 411b, liquid inlet and outlet; 411c, installation port; 412, sealing ring; 413, sealing ring block; 43, circuit connector; 310, host computer; 320, controller; 330, power module; 340, impedance detection module; 350, function switching module; 360, marking module; 370, sound and light alarm module.

The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings.

DETAILED DESCRIPTION

The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and/or" appearing in the full text is to include three parallel solutions. Taking "A and/or B" as an example, it includes solution A, or solution B, or a solution that satisfies both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

The present invention provides an ablation catheter, in particular, an ablation catheter for treating arrhythmias, but the present invention is not limited thereto.

1 and 2, in one embodiment of the present invention, the ablation catheter includes a catheter body 10, a flexible expansion body 20 and a spline 30; the flexible expansion body 20 is disposed at the distal end of the catheter body 10, and the flexible expansion body 20 is suitable for contacting the pulmonary vein vestibule or entrance, and expanding after contact to squeeze out the blood between it and the atrial wall; the spline 30 is disposed on the surface of the flexible expansion body 20 and is connected and fixed to the catheter body 10, and at least one electrode 31 is provided on the spline 30, and the electrode 31 is suitable for being electrically connected to the ablation system.

In this embodiment, the flexible expansion body 20 can be a spherical capsule, a cylindrical capsule or a special-shaped film, etc., and its material can be a polymer elastomer, such as TPU, etc. The flexible expansion body 20 can be folded and stored on the distal end of the catheter body 10 when not in use, and can be filled with liquid into a shape that matches the ablation environment during the operation. The specific shape of the flexible expansion body 20 when folded and filled is not limited here.

In this embodiment, the spline 30 can be assembled from a plurality of sheet-shaped or tubular components, or can be an integrated structure, and its overall shape can match the shape of the flexible expansion body 20, which is not limited here.

It can be understood that the present invention adopts the ablation catheter of the above structure. When the ablation catheter contacts the vestibule or entrance of the pulmonary vein, the expanded flexible expansion body 20 squeezes the blood between it and the atrial wall, and the ablation electrode 31 is located between the insulating flexible expansion body 20 and the conductive atrial wall. The electrode 31 is more closely attached, which allows the electrode 31 to apply an electric field to the atrial tissue more concentratedly, thereby effectively reducing the loss of current in the blood and side effects, greatly enhancing the safety and effectiveness of the ablation technique.

To further improve the safety and effectiveness of ablation, referring to Figures 13 and 14, in some embodiments, the flexible expansion body 20 may be provided with a filling cavity and a plurality of liquid spraying micropores 20a connected to the filling cavity. In combination with Figures 9, 13 and 14, the catheter body 10 is provided with a liquid inlet channel 10a connected to the filling cavity. The liquid inlet end of the liquid inlet channel 10a is suitable for introducing liquid, and the liquid is used to fill the flexible expansion body 20. The liquid may be a mixture of physiological saline for cooling local tissues, a liquid for anticoagulation (such as glycogen water) and a contrast agent for angiography; wherein, when the liquid pressure in the filling cavity is less than the target pressure value, the plurality of liquid spraying micropores 20a do not allow liquid to pass through; when the liquid pressure in the filling cavity is greater than or equal to the target pressure value, the flexible expansion body 20 expands until the aperture of the liquid spraying micropore 20a reaches the target aperture to allow liquid to be sprayed out.

In this embodiment, the flexible expansion body 20 may preferably be a compliant balloon, and the two ends of the balloon are fixed at the distal end of the catheter body 10 at a certain distance. Different volumes of liquid can be used to control the shape of the balloon. When a small volume of liquid (such as 3 mL) is used, the shape formed by the balloon is suitable for abutment and ablation at the entrance of the pulmonary vein. When a larger volume of liquid is used to fill the balloon (such as 6 mL), the balloon can form a flatter shape to facilitate abutment against the vestibule of the pulmonary vein for ablation.

The outer surface of the balloon is designed with molecular-level liquid-spraying micropores 20a. Under a certain pressure, the liquid-spraying micropores 20a on the balloon are not large enough to allow the internal liquid to flow out. When the pressure increases to a certain value, the compliant balloon expands, increasing the aperture of the liquid-spraying micropores 20a, thereby allowing the liquid to be sprayed out from the liquid-spraying micropores 20a.

When the liquid pressure in the balloon is lower than the opening threshold pressure of the liquid injection micropore 20a, the balloon maintains its original shape or slightly deforms to complete the sticking function; when the pressure in the balloon exceeds a certain threshold (such as 4atm), the balloon is expanded, and the liquid injection micropore 20a can be opened by pressure to release a small amount of physiological saline or medicine around the electrode 31, thereby reducing the blood concentration around the electrode 31 and reducing the electrode during the ablation process. It reduces the chance of blood clots forming in the blood and increases the safety of the operation.

13 and 14 , a plurality of liquid spraying micropores 20a can be radially arranged on the distal surface of the flexible expansion body 20. In this way, the spraying range of saline or medicine and the uniformity of liquid spraying can be effectively increased, which is conducive to further reducing the blood concentration around the electrode 31.

In order to further improve the ability to cool local tissue and reduce damage, mainly referring to Figures 1 to 6, in some embodiments, the catheter body 10 may include an outer tube 13 and an inner tube 11 arranged in the outer tube 13, the inner tube 11 forms a liquid inlet channel 10a and is provided with a liquid return channel 10b, the distal end of the inner tube 11 extends into the filling cavity and is provided with a liquid outlet hole 11a connected to the liquid inlet channel 10a and a liquid extraction hole 11b connected to the liquid return channel 10b, so that the liquid in the filling cavity circulates.

The liquid outlet hole 11a may be located in the flexible expansion body 20 and at the distal end of the ablation catheter, and the liquid extraction hole 11b may be located in the flexible expansion body 20 and at the proximal end of the ablation catheter, which is not limited here.

Both ends of the flexible expansion body 20 can be fixed on the inner tube 11. The functions of the liquid outlet hole 11a and the liquid extraction hole 11b on the wall of the inner tube 11 are to allow liquid to enter the flexible expansion body 20 during the filling process and to discharge liquid during the contraction process. The inner tube 11 wall is axially designed with multiple cavities, and through holes are opened from the outer surface of the tube wall to the tube wall cavity, as shown in Figures 5 and 6, respectively, and the liquid outlet hole 11a and the liquid extraction hole 11b are formed. In the cross-sectional direction, the liquid outlet hole 11a and the liquid extraction hole 11b can be arranged adjacently and staggered.

In this embodiment, the liquid return channel 10b can be externally connected to a suction device, and the suction device can selectively suck the liquid filling the cavity to meet different operation requirements.

In this embodiment, the liquid inlet channel 10a can be externally connected to a liquid supply device to introduce physiological saline or mixed liquid of appropriate temperature, which can enhance the ability to cool local tissues.

In addition, in some other embodiments, the liquid inlet channel 10a can also be formed by the interlayer cavity between the inner tube 11 and the outer tube 13 of the catheter body 10, and the liquid inlet channel 10a extends into the filling cavity and is provided with a liquid outlet hole 11a connected to the filling cavity.

Referring to Figures 20 to 23, in some embodiments, the catheter body 10 may also include a middle tube 12 arranged between the inner tube 11 and the outer tube 13, that is, the middle tube 12 is sleeved on the inner tube 11, and the outer tube 13 is sleeved on the middle tube 12; the inner tube 11 and the middle tube 12 can move relative to each other in the axial direction, the proximal end of the flexible expansion body 20 is connected to the middle tube 12, the proximal end of the spline 30 is fixed on the proximal end of the flexible expansion body 20, and the wire 313 of the electrode 31 is arranged between the outer tube 13 and the middle tube 12.

In this embodiment, the distal pin of the flexible expansion body 20 is fixed to the inner tube 11, and the proximal pin of the flexible expansion body 20 is connected to the middle tube 12. The inner tube 11 and the middle tube 12 can move relative to each other along the axial direction, thereby adjusting the axial position of the flexible expansion body 20 and the electrode 31 during the operation, and facilitating the filling of the flexible expansion body 20. The shape is more suitable for the ablation environment, so that the electrode 31 can be effectively attached to the ablation environment, further enhancing the safety and effectiveness of the ablation.

Based on the above embodiments, referring to Figures 1, 2, 13 and 15, in some embodiments, the ablation catheter may also include a morphology control head 14, which is fixed to the distal end of the inner tube 11, and the distal ends of the flexible expansion body 20 and the spline 30 are fixed in the morphology control head 14; the morphology control head 14 is used to control the morphology of the flexible expansion body 20 and the spline 30.

In this embodiment, when the morphology control head 14 moves, the inner tube 11 and the middle tube 12 produce relative movement, which can control the morphology change of the flexible expandable body 20 and make the morphology of the flexible expandable body 20 change to a spherical shape. This process can change the maximum radius of the flexible expandable body 20 to adapt to pulmonary veins of different sizes and shapes, so that the spline 30 of the ablation catheter can better adapt to the ablation environment, so that the electrode 31 can be better attached to the pulmonary vein vestibule or extended into the interior of the pulmonary vein for mapping and ablation, further improving the effectiveness and safety of the ablation technique.

The spline 30 can be fixed on the flexible expansion body 20. Of course, referring to Figures 20 and 21, the flexible expansion body 20 and the spline 30 can also be in a separated state. The filled flexible expansion body 20 supports the spline 30, and the distal end of the spline 30 may not be set in the shape control head 14. Only the distal end of the flexible expansion body 20 is fixed in the shape control head 14, and the shape control head 14 is used to control the shape of the flexible expansion body 20.

Mainly referring to Figures 15, 22 and 23, when the flexible expansion body 20 adopts a balloon, the spline 30 can be fixed on the balloon, and can also be installed separately from the balloon. The distal end of the spline 30 is fixed on the shape control head 14, and the proximal end is fixed on the proximal pin of the balloon; the distal pin of the balloon is fixed on the inner tube 11, and the proximal pin is fixed on the middle tube 12. The connecting wire 313 on the electrode 31 can be placed in the interlayer cavity between the inner tube 11 and the outer tube 13, and the balloon filling medium can enter and exit through the interlayer cavity between the inner tube 11 and the middle tube 12.

In this embodiment, as shown in Figures 24 and 25, the inner tube 11 can slide as the shape of the balloon changes, and changes with the change in the axial length of the balloon due to the deformation. In addition, in other embodiments, the inner tube 11 can also be controlled to slide by pushing the handle of the inner tube 11 at the operating handle end.

In order to further enhance the convenience of adjusting the shape of the balloon and improve the effect and safety of ablation, mainly referring to Figures 27 and 28, in some embodiments, the ablation catheter may also include an operating handle 40, which is connected to the proximal end of the catheter body 10; the operating handle 40 includes a handle body 41 and a pushing member 42 movably arranged on the handle body 41, the pushing member 42 is sleeved on the inner tube 11, and is used to push the inner tube 11 to move axially relative to the outer tube 13; the pushing member 42 is provided with a first connector 421 connected to the inner tube 11, and the first connector 421 is suitable for connecting to a liquid supply device to inject physiological saline into the inner tube 11 to expel the air in the tube, thereby effectively avoiding air embolism caused by surgery to the human body.

In this embodiment, a circuit connector 43 may be provided on the operating handle 40 to be electrically connected to the ablation system.

Mainly referring to Figures 29 and 30, in this embodiment, a connection seat 411 connected to the catheter body 10 may be provided in the handle body 41, and a guide wire cavity 411a, a liquid inlet and outlet 411b and a mounting port 411c are provided in the connection seat 411. The liquid inlet and outlet 411b is connected to the liquid inlet channel 10a of the catheter body 10 and is suitable for passing liquid. A second connector 422 may be connected to the outside of the liquid inlet and outlet 411b, and the mounting port 411c is provided for the outer tube 13 to be inserted for fixing. In this way, the catheter body 10 and the operating handle 40 can be conveniently connected, and the convenience of injecting liquid can be improved. Among them, the first connector 421 and the second connector 422 can both adopt Luer connectors, which are not limited here.

Further, referring to Figures 29 and 30, in order to improve the sealing performance of the connecting seat 411, a sealing ring 412 and a sealing ring stopper 413 may be provided inside the connecting seat 411. The sealing ring 412 is sleeved on the inner tube 11, and the sealing ring stopper 413 is provided on one side of the sealing ring 412 and sleeved on the inner tube 11 to block the sealing ring 412.

To improve the convenience and reliability of assembly of the spline 30, referring to Figures 10 to 12 and Figures 18 to 19, in some embodiments, a T-shaped connecting portion 301 is provided at the distal end of the spline 30, a connecting sleeve 140 is provided in the shape control head 14, the connecting sleeve 140 is provided with a groove 141 that cooperates with the T-shaped connecting portion 301, and the spline 30 and the shape control head 14 are fixed by hot melting or bonding.

In some application scenarios, as shown in Figures 7, 8, 10 and 11, the spline 30 may include multiple flexible electrode substrates 311, each of which is provided with at least one flexible electrode 312, and the multiple flexible electrode substrates 311 are arranged at intervals along the circumference of the flexible expansion body 20.

In this embodiment, as shown in Figure 10, the spline 30 is a single-piece flexible structure, and a plurality of flexible electrodes 312 are distributed on the surface, two of which are shown in the figure. The head end of the flexible electrode substrate 311 can be designed to be T-shaped to form the above-mentioned T-shaped connecting portion 301; as shown in Figures 10 and 14, a plurality of flexible electrode substrates 311 can be evenly distributed on the outer surface of the balloon, 8 of which are shown in the figure, but are not limited here.

In some other application scenarios, as shown in FIGS. 16 to 19 , the spline 30 may include an integrated flexible substrate 321 having a plurality of branch substrates, and at least one flexible electrode 312 is disposed on each branch substrate.

In this embodiment, the proximal end of the integrated flexible substrate 321 can be rolled into a cylindrical connection portion 322, which is inserted into the catheter body 10. The connection portion 322 is provided with a plurality of welding points, which are connected and conducted with the flexible electrodes 312 in a one-to-one correspondence and are suitable for welding with the wire 313 connected to the ablation system. In this way, wiring can be convenient.

In some embodiments, the multiple branch substrates are of different lengths. Specifically, the tail ends of the multiple branch substrates can be staggered in length, which can avoid the problem of concentrated accumulation of connection points (welding points) of the terminal welding cables, and is conducive to reducing the outer diameter of the device. In addition, the head end of the branch substrate can be designed as a straight section or a T-shape, which is not limited here.

To facilitate the assembly of the spline 30 , mainly referring to FIGS. 16 and 17 , in some embodiments, the distal end of the integrated flexible substrate 321 may be arranged in a ring shape to form a ring end 323 , and the ring end 323 may be attached to the surface of the flexible expansion body 20 .

In this embodiment, the distal end of the spline 30 is an integral connection, and the proximal end is also an integral connection. A wire welding point is provided at the proximal end, and several branches are distributed in the middle, 8 branches are shown in the figure, and there are several flexible electrodes 312 on each branch, two flexible electrodes 312 are shown in the figure, but this is not limited here.

Of course, referring to Figures 18 and 19, the spline 30 can also adopt a split structure in which the distal end of the branch substrate is a split structure, and the split structure is composed of multiple above-mentioned T-shaped connecting parts 301 surrounded in a non-contact manner, while the proximal end of the branch substrate is an integrated above-mentioned connecting part 322 to facilitate assembly and reduce the outer diameter of the instrument.

15 , in some embodiments, the spline 30 may be bonded to the surface of the flexible expansion body 20, and the spline 30 may be wrapped on the surface of the flexible expansion body 20 through a film ring 324. In this way, the spline 30 may be easily assembled, and the reliability of the installation of the spline 30 and the flexible expansion body 20 may be improved.

Among them, the spline 30 is further fixed by the film ring 324, so that the branches of the spline 30 can be evenly distributed on the outer surface of the flexible expansion body 20 and will not move in the circumferential direction, thereby avoiding the displacement of the electrode 31 during the operation and affecting the ablation effect.

In addition, referring to Fig. 26, the ablation catheter can be designed with a bidirectional bending function, which can make it easier for the operator to control the position of the ablation catheter during the ablation process. Specifically, as shown in Fig. 23, a bending wire 15 can be provided in the outer tube 13 to facilitate bending.

The present invention also proposes an ablation device, which includes an ablation catheter. The structure of the ablation catheter refers to the above-mentioned embodiment. Since the ablation device proposed by the present invention includes all schemes of all embodiments of the above-mentioned ablation catheter, it has at least the same technical effects as the above-mentioned ablation catheter, which are not elaborated here one by one.

Mainly referring to Figures 1, 23 and 31, in one embodiment of the present invention, the ablation device includes an ablation catheter and an ablation system. The ablation system is connected to the electrode 31 of the ablation catheter through a wire 313, and the ablation system is used to control the discharge of the electrode 31.

To facilitate wiring, in this embodiment, the wire 313 of the electrode 31 can be connected to the ablation system via a multi-way connector.

Mainly referring to FIG. 31 , in one embodiment, the ablation system may include a host computer 310, a controller 320, a power module 330, an impedance detection module 340, a function switching module 350, and a mapping module 360. The host computer 310 is electrically connected to the controller 320, the power module 330 and the impedance detection module 340 are electrically connected to the controller 320, respectively, and the function switching module 350 is electrically connected to the impedance detection module 340. The impedance detection module 340, The function switching module 350 is used to test the impedance between the electrode 31 and the reference electrode; the function switching module 350 is used to control the working state of the mapping module 360 according to the control signal of the controller 320, and select energy output, impedance detection or mapping; the mapping module 360 is used to collect, receive or input potential information, and output the mapping electrical signal. The reference electrode can be a specific electrode located at the proximal or distal end of the ablation catheter and in the blood, or the reference electrode can be any electrode 31 on the spline 30.

In this embodiment, the host computer 310 can be a computer, a laptop computer, a tablet computer, etc., and the controller 320 can be a MCU, a DSP, an FPGA, etc., which are not limited here.

In addition, referring to FIG. 31 , the ablation system may also be provided with an audio-visual alarm module 370 , which is electrically connected to the controller 320 and is used to output sound and light signals according to control signals of the controller 320 in special circumstances, so as to further improve the safety of ablation.

It can be understood that by adopting the above-mentioned ablation system and cooperating with the ablation catheter, it is possible to test the impedance between each electrode 31 and the reference electrode, and control the electrodes to discharge automatically or manually, which is beneficial for concentrating the energy of the ablation electric field on the myocardial tissue, reducing the loss of electric current in the blood and side effects, and further enhancing the safety and effectiveness of the ablation procedure.

The present invention further proposes an ablation method, based on the above-mentioned ablation device, mainly referring to FIG32 , the ablation method comprises the following steps:

S10, after the ablation catheter contacts the pulmonary vein vestibule, testing the impedance between each electrode and the reference electrode to obtain an impedance detection value;

S20, judging the application status of each of the electrodes according to the impedance detection value;

S30, turning off the electrode in the state of being surrounded by blood, and controlling the electrode in the state of being in contact with the pulmonary vein vestibule to discharge.

It should be noted that the reference electrode can be a specific electrode near the proximal end of the ablation catheter. When performing ablation, the reference electrode is in the blood. Of course, the reference electrode can also be any electrode 31 on the spline 30, as shown in Figure 1. In this case, the electrode 31 may appear in the blood or contact with the atrial tissue.

In this embodiment, after the ablation catheter contacts the pulmonary vein vestibule, the impedance between each electrode 31 and the reference electrode is tested by the impedance analysis system of the ablation device, wherein the electrode 31 with high impedance is in a state of being attached to the atrial wall, and the electrode 31 with low impedance is in a state of being surrounded by blood. The operator only needs to turn off the electrode 31 surrounded by blood and allow the electrode 31 in contact with the pulmonary vein vestibule to discharge.

It can be understood that by adopting the above ablation method, the energy of the ablation electric field can be more concentrated on the myocardial tissue, thereby effectively reducing the loss and side effects of the current in the blood, greatly enhancing the ablation effect. The safety and effectiveness of the technique.

32 and 33, in one embodiment, the reference electrode is a specific electrode located at the proximal end of the ablation catheter and in the blood; the step S20 of judging the application state of each electrode according to the impedance detection value is: the electrode corresponding to the impedance detection value being less than or equal to N times the impedance threshold of the reference electrode in the blood is determined as being in a blood surrounded state; the electrode corresponding to the impedance detection value being greater than N times the impedance threshold of the reference electrode in the blood is determined as being in a contact state with the pulmonary vein vestibule.

In this embodiment, N may be within a certain range, such as 1.2-1.4, or may be a specific value, such as 1.3, which is not limited here.

In this case, the reference electrode is in the blood, and the impedance between it and other electrodes 31 can be directly measured by the impedance analysis system. If the impedance value is less than or equal to N times the threshold value of the electrode in the blood, it means that the electrode 31 is in the blood and is not in contact with the tissue; if the impedance is higher than N times the threshold value, it means that the electrode 31 is attached to the tissue.

Mainly referring to Figures 32 and 33, in this embodiment, in step S10, it mainly includes two steps: impedance measurement S11 and obtaining impedance data S12; in step S20, it mainly includes two steps: comparing the impedance detection data with the blood threshold S21 and judging whether the impedance detection data is greater than N times the blood threshold S22.

In another embodiment, referring to FIG. 1 , FIG. 32 and FIG. 34 , the reference electrode is any electrode 31 on the spline 30 ; the step S20 of determining the application state of each electrode according to the impedance detection value includes:

S221, after obtaining all the impedance detection values, arrange them in order from small to large: R1, R2, R3...Rn;

S222, taking the smallest impedance detection value as R0, and calculating the difference ΔR between the impedance detection values of the other electrodes and R0;

S223, determining the electrode corresponding to the difference ΔR less than or equal to the first threshold as being in a blood surrounded state; determining the electrode corresponding to the difference ΔR greater than or equal to the second threshold as being in a high fit state with the pulmonary vein vestibule; determining the electrode corresponding to the difference ΔR between the first threshold and the second threshold as being in a low fit state with the pulmonary vein vestibule.

In this case, the reference electrode is any electrode 31 on the catheter spline 30, and the electrode 31 may be in the blood or in contact with the atrial tissue. In this way, the impedance variation between the electrodes 31 will be much greater than that when the reference electrode is only in the blood. The present invention uses a new algorithm to infer the contact of the electrode 31. First, all the measured impedances are arranged in order to obtain R1, R2, R3...Rn. The smallest impedance is taken as R0, and the difference ΔR between the impedance values of other electrodes 31 and R0 is used to determine the electrode attachment method. By adopting this algorithm, the changes and errors caused by the reference electrode and blood or tissue can be avoided, and the determination of the attachment state of the electrode 31 is more accurate.

Specifically, the first threshold value may be 10Ω. When the difference ΔR is less than or equal to 10Ω, it indicates that the electrode 31 is in a blood-surrounded state. The second threshold value may be 30Ω. When the difference ΔR is greater than or equal to 30Ω, it indicates that the corresponding electrode 31 is in a high fit state with the pulmonary vein vestibule. When the difference ΔR is between 10Ω and 30Ω, it indicates that the corresponding electrode 31 is in a low fit state with the pulmonary vein vestibule.

It should be noted that in the actual test, except for the strength of the fit, there was no significant difference between the electrodes 31 in the low fit state and the high fit state with the pulmonary vein vestibule, and the average treatment effect of the electrodes 31 in the blood surrounded state was significantly less than that of the electrodes 31 in the low fit state and the high fit state with the pulmonary vein vestibule. For the atrial line, the electrodes 31 in the low fit state and the high fit state with the pulmonary vein vestibule both achieved acute conduction block, while the electrodes 31 in the blood surrounded state measured the conduction gap through electroanatomical mapping.

In addition, it is worth mentioning that when in use, the impedance test interface of the ablation system can display the location (application status), serial number and measured impedance value of each electrode 31. The doctor can directly select the reference electrode on this interface, and the ablation system can automatically calculate the impedance difference ΔR between the electrodes, and according to the variation range of the difference ΔR, give different electrode 31 abutment conditions, and automatically display the abutment properties of the catheter (for example, the corresponding icon of the electrode 31 is black to indicate abutment with the tissue, and the corresponding icon is red to indicate in the blood). The ablation system can automatically control the electrode 31 abutting the tissue to be powered on and turn off the electrode 31 in the blood. At the same time, the doctor can also manually adjust the switch of the discharge electrode 31 on the artificial intelligence interface.

The above descriptions are only optional embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the contents of the present invention's specification and drawings, or directly/indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.

Claims (14)

An ablation device, comprising: An ablation catheter comprises a catheter body, a flexible expansion body, a spline and a shape control head; the flexible expansion body is arranged at the distal end of the catheter body, the flexible expansion body is suitable for contacting the pulmonary vein vestibule or entrance, and squeezing out the blood between it and the atrial wall after expansion contact; the spline is wrapped on the surface of the flexible expansion body through a film ring and is connected and fixed to the catheter body, and at least one electrode is arranged on the spline; the catheter body comprises an outer tube, an inner tube arranged in the outer tube and a middle tube arranged between the inner tube and the outer tube, and the inner tube and the middle tube can be The flexible expandable body moves relatively along the axial direction, the proximal end of the spline is connected to the proximal end of the flexible expandable body, and the wire of the electrode is arranged between the outer tube and the middle tube; the morphology control head is fixed to the distal end of the inner tube, and the distal ends of the flexible expandable body and the spline are fixed in the morphology control head; the morphology control head is used to control the morphology of the flexible expandable body and the spline; or the distal end of the flexible expandable body is fixed in the morphology control head; the morphology control head is used to control the morphology of the flexible expandable body; and An ablation system is connected to the electrode through a wire, and the ablation system includes an impedance detection module for testing the impedance detection value between the electrode and a reference electrode. The ablation system determines the application state of each electrode according to the impedance detection value, turns off the electrode in the blood surrounding state, and controls the discharge of the electrode in the contact state with the pulmonary vein vestibule; when the reference electrode is any electrode on the spline, after obtaining all the impedance detection values, they are arranged in order from small to large as: R1, R2, R3...Rn; the smallest impedance detection value is taken as R0, and the difference ΔR between the impedance detection values of the other electrodes and R0 is calculated; the electrode corresponding to which the difference ΔR is less than or equal to the first threshold is determined to be in the blood surrounding state; the electrode corresponding to which the difference ΔR is greater than or equal to the second threshold is determined to be in a high fit state with the pulmonary vein vestibule; the electrode corresponding to which the difference ΔR is between the first threshold and the second threshold is determined to be in a low fit state with the pulmonary vein vestibule; the first threshold is 10Ω, and the second threshold is 30Ω. The ablation device as described in claim 1 is characterized in that the flexible expansion body is a spherical capsule, a cylindrical capsule or a special-shaped film; the flexible expansion body is provided with a filling cavity and a plurality of liquid injection microholes connected to the filling cavity, the catheter body is provided with a liquid inlet channel connected to the filling cavity, the liquid inlet end of the liquid inlet channel is suitable for passing liquid, the liquid is used to fill the flexible expansion body, and the liquid is a mixture of physiological saline for cooling local tissue, a drug solution for anti-coagulation and a contrast agent for angiography. The ablation device according to claim 2, characterized in that when the liquid pressure in the filling chamber is less than the target pressure value, the plurality of liquid injection micropores do not allow liquid to pass through; When the body pressure is greater than or equal to the target pressure value, the flexible expansion body expands until the aperture of the liquid spraying micropore reaches the target aperture to allow liquid to be sprayed out; and/or The plurality of liquid spraying micropores are radially arranged on the distal end surface of the flexible expansion body. The ablation device according to claim 2, characterized in that the liquid inlet channel is formed between the inner tube and the outer tube, the liquid inlet channel extends into the filling cavity and is provided with a liquid outlet hole communicating with the filling cavity; or The inner tube forms the liquid inlet channel and is provided with a liquid return channel. The distal end of the inner tube extends into the filling cavity and is provided with a liquid outlet hole connected to the liquid inlet channel and a liquid extraction hole connected to the liquid return channel, so that the liquid in the filling cavity circulates. The ablation device as described in claim 2 is characterized in that the ablation catheter also includes an operating handle, which is connected to the proximal end of the catheter body; the operating handle includes a handle body and a pushing member movably arranged on the handle body, the pushing member is sleeved on the inner tube, and is used to push the inner tube to move axially relative to the outer tube; the pushing member is provided with a first connector connected to the inner tube, and the first connector is suitable for connecting to a liquid supply device to inject physiological saline into the inner tube to expel air in the tube, so as to prevent surgery from causing air embolism to the human body. The ablation device as described in claim 5 is characterized in that a connecting seat connected to the catheter body is provided in the handle body, a wire cavity and a liquid inlet and outlet are provided in the connecting seat, and the liquid inlet and outlet are connected to the liquid inlet channel and are suitable for passing liquid. The ablation device as described in claim 6 is characterized in that a sealing ring and a sealing ring stopper are provided in the connecting seat, the sealing ring is sleeved on the inner tube, and the sealing ring stopper is provided on one side of the sealing ring and sleeved on the inner tube to block the sealing ring. The ablation device as described in claim 1 is characterized in that a T-shaped connecting portion is provided at the distal end of the spline, a connecting sleeve is provided inside the morphology control head, the connecting sleeve is provided with a groove that cooperates with the T-shaped connecting portion, and the spline and the morphology control head are fixed by hot melting or bonding. The ablation device as described in claim 1 is characterized in that the spline includes a plurality of flexible electrode substrates, each of which is provided with at least one flexible electrode, and the plurality of flexible electrode substrates are arranged at intervals along the circumference of the flexible expansion body. The ablation device according to claim 1, characterized in that the spline comprises an integral flexible substrate having a plurality of branch substrates, each of the branch substrates is provided with at least one of the electrodes, and the electrodes are flexible electrodes; The proximal end of the integrated flexible substrate is curled into a cylindrical connecting portion. The connecting part is inserted into the catheter body, and a plurality of welding points are arranged on the connecting part. The plurality of welding points are connected and conducted with the flexible electrodes one by one and are suitable for welding with the wires connected to the ablation system; and/or the distal end of the integrated flexible substrate is arranged in a ring shape and is attached to the surface of the flexible expansion body. The ablation device as described in claim 10 is characterized in that the plurality of branch substrates are of different lengths. The ablation device according to any one of claims 9 to 11, characterized in that the spline is bonded to the surface of the flexible expansion body. The ablation device according to claim 1, characterized in that the ablation system further comprises a host computer, a controller, a power module, a function switching module and a mapping module, the host computer is electrically connected to the controller, the power module and the impedance detection module are electrically connected to the controller respectively, and the function switching module is electrically connected to the impedance detection module; The function switching module is used to control the working state of the mapping module and select energy output, impedance detection or mapping according to the control signal of the controller; The mapping module is used to collect, receive or input potential information and output a mapping electrical signal. The ablation device according to claim 13, characterized in that the control method of the ablation device comprises the following steps: After the ablation catheter contacts the pulmonary vein vestibule, testing the impedance between each of the electrodes and the reference electrode to obtain an impedance detection value; According to the impedance detection value, determining the application state of each of the electrodes; The electrode in the state of being surrounded by blood is turned off, and the electrode in the state of being in contact with the vestibule of the pulmonary vein is controlled to discharge.