ABLATION DEVICE

An ablation device includes an outer tube; an ablation assembly, provided at a distal end of the outer tube and including a radially collapsible and expandable support frame and a plurality of electrodes arranged on the support frame, wherein at least one first electrode used for mapping is included in the plurality of electrodes; and a connector, provided at a proximal end of the outer tube, the connector including a plurality of conductive terminals, the connector being electrically connected to the plurality of electrodes through the plurality of conductive terminals, the plurality of conductive terminals including at least one first terminal, and each first terminal being electrically connected to one corresponding first electrode in a one-to-one correspondence mode, so that when the connector is connected to an external mapping device, the first electrode implements mapping through the first terminal.

The present application is a National Stage of International Application No. PCT/CN2022/139652, filed Dec. 16, 2022, which claims priority to Chinese Patent Application No. 202210077700.5 (entitled “Ablation Device”) filed with China National Intellectual Property Administration on Jan. 21, 2022, which are incorporated herein by reference in their entirety.

TECHNICAL FIELD

The present invention relates to the technical field of medical devices, and particularly to an ablation device.

BACKGROUND

Electrophysiological mapping plays a very important role in the field of electrophysiology, which is used to record electrophysiological signals in vivo, so as to find abnormal lesions and guide ablation accordingly. After ablation treatment, the effect of treatment is then verified by mapping.

The traditional electrophysiological mapping is generally implemented by using a mapping catheter and the ablation therapy is implemented by using an ablation catheter. This leads to the need to insert and retract multiple devices in and from the patient's body during the operation. For example, during the procedure, a mapping catheter is used for electrophysiological mapping. Once the mapping is completed, the mapping catheter can be removed, an ablation catheter will be then inserted in situ. After the ablation, the mapping catheter is inserted again for mapping, to verify the effect of the ablation treatment. However, it needs to introduce both ablation catheter and the mapping catheter during the procedure which causes many defects such as complicated operation steps, long operation time and high cost.

SUMMARY

To solve the above problems, the present invention provides an ablation device, which includes an outer tube; an ablation assembly, provided at a distal end of the outer tube and including a radially collapsible and expandable support frame and a plurality of electrodes arranged on the support frame, wherein the plurality of electrodes includes at least one first electrode for mapping; and a connector, provided at a proximal end of the outer tube, wherein the connector includes a plurality of conductive terminals, the connector is electrically connected to the plurality of electrodes by means of the plurality of conductive terminals, the plurality of conductive terminals (32) includes at least one first terminal, and each of the at least one first terminal is electrically connected to one corresponding first electrode in a one-to-one correspondence mode, so that when the connector is connected to an external mapping device, the first electrode implements mapping by means of the first terminal.

According to the ablation device provided in the embodiments of the present invention, a target ablation area can be ablated by means of the radially expandable support frame and the plurality of electrodes arranged on the support frame. Moreover, the first electrode(s) of the electrodes is/are connected to the first terminal(s) on the connector in a one-to-one correspondence mode. Therefore, when the connector is connected to an external mapping device, the first electrode can also be used for electrophysiological mapping by the corresponding first terminal. In this way, the ablation device has the functions of both mapping and ablation, making the surgical operations more convenient, and improving the operation efficiency.

LIST OF REFERENCE NUMERALS

DESCRIPTION OF EMBODIMENTS

Typical embodiments embodying the characteristics and advantages of the present invention will be described in detail hereinafter. It should be understood that various variations of the present invention can be made in various embodiments, without departing from the scope of the present invention. The description and accompanying drawings herein are provided essentially for illustration, instead of limiting the present invention.

In the description of the present application, it should be understood that directions or location relationships indicated by the terms “center”, “longitudinal”, “transverse”, “length”, “width”, “thickness”, “upper”, “lower”, “front”, “rear”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inner”, “outer”, “clockwise”, and “counterclockwise” are directions or location relationships shown based on the accompanying drawings, which are merely provided for the purpose of describing the present application and simplifying the description, but are not used to indicate or imply that a device or an element must have a particular direction, or must be constructed and operated in a particular direction. Therefore, they cannot be construed as limiting on the present application. Furthermore, the terms “first”, and “second” are used merely for the purpose of description, and shall not be construed as indicating or implying relative importance or implying a quantity of indicated technical features Therefore, a feature restricted by “first” or “second” may explicitly or implicitly include one or more of the features. In the description of the present application, “a plurality of” means two or more, unless explicitly specified.

An embodiment of the present invention provides an ablation device having mapping function, which can be used for cardiac ablation, by delivering the ablation device to a specific position of the heart by percutaneous puncture and ablating the pulmonary vein, the left atrial appendage, or trigger foci (such as superior vena cava and coronary sinuatrial orifice) of non-pulmonary vein origins combined with typical atrial flutter by using an external ablation energy source such as pulsed electric field, radio frequency or microwave, so as to achieve the effect of electrical isolation. It can be understood that cardiac ablation is a typical application of the ablation device, and if feasible, the ablation device can also be applied to other tissues, which is not limited herein.

The ablation device is provided with an electrode for ablation, which can also be directly used for electrophysiological mapping before and after ablation. In this way, the ablation device has the functions of mapping and ablation at the same time, making the surgical operations more convenient, and improving the success rate of surgery.

To facilitate the understanding of the technical solutions of the present invention, the present invention will be described in detail in connection with several embodiments. It is to be understood that where there are no contradictions, features in various embodiments of the present invention can be combined with each other without conflict.

For ease of description, the definitions of some terms involved herein are interpreted as follows:

Proximal and distal ends: In the field of interventional medical devices, the end of a medical device inserted into the human or animal body that is close to an operator is called “proximal” end, and the end far away from the operator is called “distal” end. The “proximal end” and “distal end” of any components in the ablation device are defined herein according to this rule. “Axial direction” generally refers to a length direction of a medical device when it is delivered, “radial direction” generally refers to a direction of the medical device that is perpendicular to its “axial direction”, and “circumferential direction” generally refers to a direction around the “axial direction”. The “axial direction”, “radial direction” and “circumferential direction” of relevant components in the ablation device are defined herein according to this rule. These definitions are merely provided for convenience of expression and do not constitute a limitation on the present application. If there are any exceptions, a reasonable explanation can be made by combining the attached drawings and the common understanding of the terms by those skilled in the art.

Insulating layer: It is formed by insulating a surface of a component, and is used to insulate this portion of the component. Particularly, the insulating layer is formed by coating, at a position intended to be insulated, an insulating coating material, including, but not limited to, a Parylene coating, a poly-tetra-fluoroethylene (PTFE) coating, and a polyimide (PI) coating; or by applying, at a position intended to be insulated, an insulating film, including, but not limited to, fluorinated-ethylene-propylene (FEP), polyurethane (PU), ethylene-tetra-fluoro-ethylene (ETFE), polyfluoroalkoxy (PFA), PTFE, poly-ether-ether-ketone (PEEK), and silica gel; or by arranging an insulating sleeve tube around at a position intended to be insulated, wherein the material of the insulating sleeve tube includes, but is not limited to, FEP, PU, ETFE, PFA, PTFE, PEEK, and silica gel.

Pulsed-field ablation: Irreversible electric breakdown, also known as irreversible electroporation (IRE) in the medical field, of cell membrane is caused by a high-intensity pulsed electric field, to induce cell apoptosis, so that non-thermal ablation of cells is realized without the use of heat sink effect. A high-voltage pulse sequence generates less heat and does not require the cooling with physiological saline, effectively reducing the occurrence of steam pops, eschar and thrombosis. The duration of pulsed-field ablation is short. The time of treatment by applying a group of pulse sequences is less than 1 minute, and the whole ablation time is generally less than 5 minutes. Moreover, because different tissues have different response thresholds to pulsed electric field, it is possible to ablate the myocardium without interfering with other adjacent tissues, thus avoiding accidental injury to adjacent tissues. In addition, compared with other forms of energy, pulsed-field ablation does not require heat conduction to ablate the deep tissue, because all myocardial cells distributed within a certain electric field intensity will be electroporated, reducing the requirement for contact pressure of a catheter during the ablation. Therefore, even if the ablation device is not completely attached to an inner wall of a tissue, the ablation effect of IRE will not be affected.

FIRST EMBODIMENT

Referring toFIG.1a, an ablation device according to this embodiment mainly includes an outer tube1, an ablation assembly2provided at a distal end of the outer tube1, and a connector3provided at a proximal end of the outer tube1. In this embodiment, the ablation device further includes a driving member4inserted in the outer tube1and connected to the ablation assembly2. The ablation device can be delivered to the interior of the heart by a delivery device that generally includes a sheath, and a handle, etc. For the specific structure of the delivery device, reference can be made to related technologies in the art. The connector3of the ablation device can be arranged on a handle100, as shown inFIG.1b.

Referring toFIG.1aagain, the outer tube1has a hollow tubular structure, with an axis extending in a distal-proximal direction. The outer tube1has a single axial lumen or a central lumen (not shown) therein. According to requirement in practice, the outer tube1can also be constructed to have a plurality of lumens, to accommodate, a pull wire, a lead wire, a sensor cable, and any other wires, cables and/or tubes and structures that may be needed in a specific application therein.

It can be understood that the outer tube1can also be of any suitable configuration, and made of any suitable material. For example, one configuration includes an outer wall made of a polymer material such as polyurethane or polyether-block-amide (PEBAX). The outer tube1has certain flexibility and can be bent to adapt to the bending structure inside the heart.

The ablation assembly2includes a radially collapsible and expandable support frame21and a plurality of electrodes22arranged on the support frame21.

A proximal end of the support frame21is connected to the distal end of the outer tube1, and a distal end of the support frame21is gathered towards the axis L of the outer tube1. In this embodiment, the distal end of the support frame21is converged at the distal end of the driving member4. FIG. la schematically shows a structure in which the support frame21is in an expanded state. In this case, the two ends of the support frame21are converged and the intermediate portion is expanded, and the contour of the support frame21is substantially in the shape of a mesh basket. The support frame21may also have other configurations, such as spherical, egg-shaped, pumpkin-shaped, lantern-shaped, and oval-shaped configurations etc.

On the basis of the structure shown inFIG.1a, the support frame21can be radially inwardly collapsed relative to the axis L of the outer tube1, that is, the intermediate portion of the support frame21can also be gathered towards the axis L of the outer tube1. The support frame21will be straightened to have a substantially linear shape in a collapsed state. The axial length of the support frame21in the collapsed state will be greater than that in the expanded state.

In the collapsed state, the support frame21can be received in a sheath, for convenient delivery to the human body through the sheath. After delivery to a target ablation site through the sheath, the support frame21is released from the sheath, and then radially expanded to the expanded state shown inFIG.1a.

The radial expansion of the support frame21may be self-expansion and unfolded when it extends out of the sheath, or the support frame21may expand radially by human manipulation or intervention after it extends out of the sheath. For example, in this embodiment, the driving member4can be used to control the collapse and expansion of the support frame21, which will be described in detail below.

The support frame21can be prepared by cutting a pipe made of an elastic metal or by weaving an elastic metal wire, or processed by combining local weaving with local pipe cutting, wherein the parts obtained by different processing methods can be welded or fixed to each other by coupling elements. The pipe may be made of a metal or nonmetal material, preferably a memory metal material or a nickel-titanium alloy material. In this embodiment, the support frame21can be cut and shaped from a nickel-titanium alloy pipe.

Particularly, the support frame21includes a plurality of bearing rods211arranged circumferentially around the axis L of the outer tube1. The plurality of bearing rods211define a radially collapsible and expandable structure. In this embodiment, six bearing rods211are arranged circumferentially around the axis L of the outer tube1, and the bearing rods211are uniformly arranged in the circumferential direction. In other embodiments, four, five, six, seven, eight, nine, ten, eleven, twelve or any other suitable number of bearing rods211can be provided. The bearing rods211may be evenly or unevenly distributed at intervals in the circumferential direction.

A proximal end of each bearing rod211is connected to the distal end of the outer tube1, and distal ends of the plurality of bearing rods211are gathered towards the axis L of the outer tube1. In this embodiment, the distal end of each bearing rod211is connected onto the driving member4, and the support frame21can be collapsed or expanded under the control of the driving member4.

The driving member4is coaxially arranged in the outer tube1. A distal end of the driving member4extends distally out of the distal end of the outer tube1and is connected to the distal end of each bearing rod211. The driving member4can move axially relative to the outer tube1, to drive the support frame21to expand or contract in the radial direction.

A proximal end of the driving member4can be connected to the handle100, and the handle100pulls the driving member4to drive the driving member4to move in the axial direction. When the driving member4moves relative to the outer tube1in a distal-to-proximal direction, the distal end of each bearing rod211moves proximally with the driving member4, and the intermediate portion of the bearing rod211will gradually swell outward in the radial direction. As a result, the outer diameter of the support frame21will increase, that is, the support frame21expand outwards. On the contrary, when the driving member4moves relative to the outer tube1in a proximal-to-distal direction, the distal end of each bearing rod211moves distally with the driving member4, the bearing rod211is straightened, and the intermediate portion of the bearing rod211is gradually drawn close to the axis L of the outer tube1in the radial direction. As a result, the outer diameter of the support frame21will decrease. Therefore, the outer diameter of the support frame21can be flexibly adjusted by the driving member4, so that the support frame21can adapt to blood vessels (such as pulmonary veins) or other tissues with different diameters, and a target ablation area can be ablated with any appropriate outer diameter, instead of ablation with the restriction that the support frame21needs to have the maximum axial compression (that is, the maximum radial expansion). This improves the adaptability of the support frame21to the anatomical shapes of different target ablation areas, and facilitates the operation of the ablation device, so as to achieve a good ablation effect.

The driving member4can be a steel cable, a flexible polyimide (PI) pipe, a fluorinated polyethylene (PDFE) pipe, a stainless steel pipe, or a pipe made of other polymer materials. When the driving member4has a tubular structure, the driving member4has a certain structural strength, to buffer the external force on the bearing rod211, and effectively ensure the position stability of the bearing rod211.

In some embodiments, the ablation device may not be provided with the driving member4, and the support frame21expands in the radial direction by self-expansion. In this case, the diameter of the support frame21is not adjustable, and it is applicable to a target ablation area with a fixed size.

A plurality of electrodes22are arranged on each bearing rod211of the support frame21. After the support frame21expands radially, each bearing rod211can be attached to an inner wall of a tissue inside the heart, and the tissue is ablated by the electrode22using ablation energy. It should be noted that the electrodes22are arranged on the support frame21, and during the radial expansion of the support frame21, the radial positions of the electrodes22may change with the expansion of the support frame21.

In this embodiment, each bearing rod211is provided with a plurality of electrodes22at intervals in the axial direction. For the plurality of bearing rods211, the electrodes22correspond one-to-one in the axial direction and are arranged at intervals in the circumferential direction around the axis L of the outer tube1. In other embodiments, one or more electrodes22may be provided only on some of the bearing rods211.

As an example, three electrodes22are provided on each bearing rod211in this embodiment. It can be understood that the number of electrodes22can also be set reasonably according to actual needs. The position of the bearing rod211farthest from the axis L of the outer tube1in the radial direction is called the outermost end2111. In this embodiment, each electrode22is arranged between the distal end and the outermost end2111of the bearing rod211, so that the distance between the electrodes22can be ensured to be in a relatively suitable range to avoid arcing, and the electrodes22can be ensured to well conform to the atrial tissue and maintain good attachment. One of the electrodes22is located at the outermost end2111.

The electrode22may be a ring electrode, a sheet electrode, a punctiform electrode or a spherical electrode, which is not particularly limited in this embodiment. The electrode22can be made of a platinum-iridium alloy, gold, other platinum alloys, stainless steel, nickel-titanium or any other biocompatible medical metals.

The inner wall of each electrode22is welded with a wire5having an insulating layer. The bearing rod211includes a rod body and an insulating sleeve tube arranged around the rod body. The insulating sleeve tube is made of PEBAX tube or other polymer insulating materials, which ensures the insulation between the electrode22and the rod body. One, two or more layers of the insulating sleeve tube can be provided, which is not limited herein. The cross-sectional shape of the rod body can be oval, circular, rectangular, semi-circular, round drum or other shapes, which is not limited herein. In this embodiment, the rod body is made of a NiTi wire, so that the rod body has excellent elasticity and strength and can be well attached to the target ablation area. It is to be understood that the rod body can also be made of other materials, such as stainless steel or polymer materials.

The electrode22is arranged around on the insulating sleeve tube of the bearing rod211, to ensure the insulation between the electrode22and the rod body. The wire5is positioned between the rod body and the insulating sleeve tube. That is, the inner surface of each electrode22is connected to the connector3by the wire5extending through the surface of the insulating sleeve tube and along the bearing rod211and the outer tube1. The electrode22and the wire5are connected by welding or other special processes.

The connector3generally includes an insulating housing31and a plurality of conductive terminals32disposed on the insulating housing31. The connector3can be mounted on the handle100through the insulating housing31. The plurality of conductive terminals32can be arranged according to the actual needs, and are not limited to the arrangement shown inFIG.1a. The structure of the conductive terminal32is not limited, and may be a solid needle terminal, or pogo pin, etc.

The plurality of conductive terminals32are electrically connected to the plurality of electrodes22of the ablation assembly2through the wires5, and the wire5and the conductive terminal32can be connected by welding. By means of the conductive terminals32, the connector3can be optionally connected to an external ablation energy source200(as shown inFIG.1c) or an external mapping device300(as shown inFIG.1c). When the connector3is connected to the external ablation energy source200, the ablation energy can be transmitted to the electrode22through the conductive terminal32and the wire5, whereby the electrode22can be used for ablation. When the connector3is connected to the external mapping device, the electrode22meeting the mapping requirements can transmit the collected electrophysiological signals to the outside through the wire5and the conductive terminal32.

The complete connection relationship between the plurality of conductive terminals32and the plurality of electrodes22is not shown inFIG.1a. Depending on the different functions of the electrode22, the conductive terminal32and the electrode22may have correspondingly different connection relationships. For example, at least one first electrode22ais included in the plurality of electrodes22of the ablation assembly2, wherein the first electrode22acan be used for mapping. The first electrode22ais used for ablation when ablation is needed, and for mapping before and after ablation.FIG.1aexemplarily shows two first electrodes22a,and the two first electrodes22aare arranged on two respective bearing rods211. Corresponding to the two first electrodes22a,two first terminals32aare included in the plurality of conductive terminals32of the connector3, and each first terminal32ais electrically connected to a corresponding first electrode22ain a one-to-one correspondence mode. That is, one first terminal32ais only connected to one first electrode22athrough a corresponding wire5, and the one first terminal32awill not be connected to other electrodes22. In this case, after the electrophysiological signal collected by each first electrode22ais transmitted through the first terminal32a,it can clearly and uniquely reflect the electrophysiological state at a specific position in the human body, that is, the position where the first electrode22ais located. Therefore, electrophysiological mapping can be accurately carried out, and the first electrode22acan be used for mapping through the corresponding first terminal32a.The number and arrangement of the first electrodes22acan be varied, and are not limited to the two shown inFIG.1a.

Furthermore, because the first electrode22aand the first terminal32aare electrically connected in a one-to-one correspondence manner, when the connector3is connected to the external ablation energy source200(as shown inFIG.1c), the first terminal32acan be independently controlled to power on or off the corresponding first electrode22a.The area where the first electrode22ais located can be locally ablated when the first electrode22ais powered on, with no need to ablate the whole target ablation area. Therefore, the ablation device can realize regional ablation. It is possible to avoid the injury of the tissue that is not intended to be ablated by regional local ablation. Ablation energy can directionally act on the tissue intended to be ablated, thus increasing the utilization rate of ablation energy, reducing the dissipation of ablation energy in blood, and reducing unwanted bubbles generated in electrolysis of blood. During the regional ablation, not all the electrodes22need to be electrified, so as to reduce the total current during ablation, alleviate possible stimulation to the body, reduce short circuit or arcing caused by too many electrodes22, and improve the safety.

In some embodiments of the present disclosure, when the connector3is connected to the external ablation energy source200, the first electrode22acan be independently controlled by the first terminal32ato discharge, so that the first electrode22acontrolled to discharge can transfer the ablation energy outputted by the external ablation energy source200to the area where the first electrode22ais located for local ablation.

In this embodiment, the plurality of electrodes22of the ablation assembly2also include a plurality of second electrodes22bfor ablation only.FIG.1aexemplarily shows two second electrodes22b,and the two second electrodes22bare arranged on two respective bearing rods211. One second terminal32belectrically connected to the two second electrodes22bis included in the plurality of conductive terminals32of the connector3. That is, the two second electrodes22bare connected to this second terminal32bthrough their respective wires5. Therefore, the two second electrodes22bconnected to the second terminal32bwill have the same polarity during ablation.

The number of the second electrode22bis not limited to two as shown inFIG.1a, and more second electrodes22bcan be provided. The number of the second terminal32bis less than or equal to that of the second electrode22b.When the number of the second terminal32bis less than that of the second electrode22b,the plurality of second electrodes22bcan be electrically connected to the same second terminal32bin a mode of connection as shown inFIG.1a, so as to reduce the number of the second terminal32b.When the number of the second terminal32bis equal to that of the second electrode22b,the second terminals32bcan be used to endow the respective second electrodes22bwith different polarities as required, which is beneficial to the formation of different electric field distributions to meet different ablation requirements. In this case, the second terminals32bcan actually be connected to the second electrodes22bin a one-to-one correspondence mode, and regional ablation can also be achieved in this instance.

It is to be noted that the above description of the connection relationship between the electrode22and the conductive terminal32with reference to FIG. la is merely a schematic illustration of the principle. In practical connection, a reasonable connection relationship can be formed between the electrode22and the conductive terminal32according to the function of the electrode22, and the corresponding function of the electrode22can be realized with the aid of the conductive terminal32.

When the electrode22is used for ablation, the connector3transfers the ablation energy of the connected external ablation energy source200to the electrode22via the conductive terminal32, and then the electrode22ablates the target ablation area. In this embodiment, all electrodes22including the first electrode22aand the second electrode22bcan be used for ablation.

Taking the external ablation energy source200being of pulsed energy as an example, the voltage range of the pulse signal received by the electrode22is in the range of 500V to 3000V, including all values and subranges therebetween; and the pulse frequency is in the range of 500 Hz to 500 kHz, including all values and subranges therebetween. The pulse energy can be a unipolar high-voltage pulse power supply or a bipolar high-voltage pulse power supply. The waveform of a bipolar high-voltage pulse signal has alternating pulses of positive and negative polarity in each period. The maximum voltage that the wire5bears is 3000 V. All the electrodes22can be divided into one or more positive-negative electrode sets. In some embodiments, a plurality of electrodes22on each bearing rod211can be arranged to have the same polarity that is opposite to the polarity of the electrodes22on adjacent carrier rods211. In some other embodiments, the polarities of two adjacent electrodes22on each bearing rod211are opposite, and the polarities of the axially corresponding electrodes22on adjacent bearing rods211are opposite; or the polarities of two adjacent electrodes22on each bearing rod211are opposite, and the polarities of the axially corresponding electrodes22on adjacent bearing rods211are the same. The energy pulse received by the electrode22include single-phase pulses or biphasic pulses, and each electrode22can be configured to have single-phase or biphasic pulses with different parameters such as voltage, pulse width, repetition frequency, duty ratio and pulse number.

When the electrode22is used for mapping, the connector3is connected to the external mapping device300. In this case, only the first electrode is used for mapping. The electrophysiological signal of the target ablation area is collected by the first electrode22aand then transmitted to the external mapping device300through the first terminal32a.

The first electrode22acan be arranged and used for mapping through many methods, which are described below. For case of description, this embodiment is described by way of example in which three electrodes22are provided on each bearing rod211. The three electrodes22on each bearing rod211are called electrode22#1, electrode22#2, and electrode22#3in sequence from the distal end to the proximal end, wherein the electrode22#3is located at the outermost end2111of the bearing rod211.

First method: One first electrode22ais provided on at least two respective bearing rods211.

In this method, when the connector3is connected to the external mapping device, any two of the first electrodes22aare used as a mapping electrode pair for mapping.

Any electrode22on the bearing rod211can be used as the first electrode22a,and the axially corresponding electrodes22on different bearing rods211can be used as the first electrodes22a.That is, the electrodes22#1on the bearing rods211are used as the first electrodes22a,the electrodes22#2on the bearing rods211are as the first electrodes22a,or the electrodes22#3on the bearing rods211are as the first electrodes22a.In addition, the electrodes22on two bearing rods211that are not corresponding to each other in the axial direction may be used as the first electrodes22a.For example, the electrode22#1on one bearing rod211is used as the first electrode22a,and the electrode22#3on another bearing rod211is used as the first electrode22a.

Preferably, all the bearing rods211are respectively provided with one first electrode22a,so more choices are feasible. Moreover, as the number of the first electrode22aincreases, the scope and efficiency of collection of the electrophysiological signals are improved, making the mapping more accurate.

Taking one first electrode22abeing provided on each bearing rod211as an example. During mapping, the first electrodes22aon two adjacent bearing rods211form a mapping electrode pair for electrophysiological mapping. For example, two adjacent electrode22#3form a mapping electrode pair. Definitely, any two first electrodes22amay also be used as a mapping electrode pair. For example, any two electrodes22#3are used as the first electrodes22aand form a mapping electrode pair.

Particularly, it is to be noted that the electrode22#3on each bearing rod211is preferably used as the first electrode22a.Compared with the case where the electrode22#1or the electrode22#2is used as the first electrode22a,because the electrode22#3is located at a position on the bearing rod211that is farthest from the axis L of the outer tube1in the radial direction, that is, a position where the support frame21has the largest radial dimension after expansion, the electrode22#3can be full attached to the target ablation area after the support frame21is expanded, so the attachment is good and the potential can be mapped more easily.

Second method: Two non-adjacent first electrodes22aare included in a plurality of electrodes22arranged on at least one bearing rod211.

In this method, when the connector3is connected to the external mapping device, any two first electrodes22aform a mapping electrode pair for mapping. It is preferable that two first electrodes22aon the same bearing rod211are used as a mapping electrode pair. However, in other embodiments, two first electrodes22aon different bearing rods211may be used as a mapping electrode pair.

Corresponding to the method of arrangement of the electrode22in this embodiment, the electrode22#1and the electrode22#3on the bearing rod211are used as the first electrodes22a.The first electrodes22ainclude the electrode22#3at the outermost end2111of the bearing rod211, and thus has the advantage of good attachment.

Preferably, each of the bearing rods211has two first electrodes22a.Therefore, in this method, twelve first electrodes22aare provided in total, which can form six mapping electrode pairs. The increase in number can greatly improve the scope and efficiency of collection of the electrophysiological signals, thus making the mapping more accurate. When the whole support frame21is attached to the target ablation area, electrocardic conduction signals in multiple directions can be collected, making the collected potential signals more accurate and avoiding the omission of a potential signal conducting in a direction perpendicular to the recording direction.

Third method: Two-adjacent first electrodes22aare included in a plurality of electrodes22arranged on at least one bearing rod211.

In this method, when the connector3is connected to the external mapping device, any two first electrodes22aform a mapping electrode pair for mapping. Preferably, two first electrodes22aon the same bearing rod211are used as a mapping electrode pair for mapping. However, in other embodiments, two first electrodes22aon different bearing rods211may be used as a mapping electrode pair.

Correspondingly, in this embodiment, the electrode22is arranged in such a manner that the electrode22#1and the electrode22#2on the bearing rod211are used as the first electrodes22a,or the electrode22#2and the electrode22#3on the bearing rod211are used as the first electrodes22a.

Preferably, the electrode22#2and the electrode22#3are used as the first electrodes22a.The first electrodes22ainclude the electrode22#3at the outermost end2111of the bearing rod211, and thus has the advantage of good attachment.

In this method, preferably each of the bearing rods211is provided with two first electrodes22a.Twelve first electrodes22aare provided in total, which can form six mapping electrode pairs. The increase in number can improve the accuracy of mapping.

Over the radial dimension change of the support frame21, the distance between two adjacent first electrodes22ais constantly small, the far-field interference is also constantly small, and the electric field interference is small in this method, so the mapping accuracy is high.

Forth method: Three or more electrodes22on at least one bearing rod211are all the first electrodes22a.

In this method, when the connector3is connected to the external mapping device, any two first electrodes22aform a mapping electrode pair for mapping.

In this embodiment, preferably, the electrodes22on all the bearing rods211are all the first electrodes22a.Accordingly, the ablation device has eighteen first electrodes22a. The increase in number can effectively improve the accuracy of mapping.

In the methods listed above, different mapping methods can be formed by setting different first electrodes22a.Each first electrode22aand a corresponding first terminal32ain the connector3can be electrically connected in a one-to-one correspondence mode as shown in the embodiment inFIG.1a. The schematic views of specific connections in various methods are omitted here.

In the methods listed above, in other embodiments, as shown inFIG.1d, the ablation device may further include a reference electrode6. Each reference electrode6is electrically connected to one of the conductive terminals32in the connector3in a one-to-one correspondence mode. The reference electrode6can be located on the outer tube1or the driving member4, and the reference electrode6and the first electrode22aform a mapping electrode pair. In some embodiments, as shown inFIG.1e, the reference electrode6can also be arranged at a most distal end of the support frame21, and the reference electrode6and the first electrode22aon the bearing rod211form a mapping electrode pair. In some cases, the reference electrode can also be provided on the body surface, and the reference electrode and one first electrode22aon the ablation device form a mapping electrode pair.

When the ablation device according to this embodiment is used, the support frame21of the ablation assembly2is received in the collapsed state in a sheath, the ablation assembly2is delivered by the sheath to an intended position in the human body, then the sheath is withdrawn, then the support frame21is released, the support frame21is attached to a target ablation area, the connector3is connected to the external mapping device at this time, and the first electrode22aimplements the mapping with the aid of the first terminal32a.After the mapping is completed, the connector3is switched to connect to the external ablation energy source, the ablation energy is transferred by the conductive terminal32to the electrode22, and the electrode22ablates the target ablation area by pulsed-field ablation or by ablation in other energy forms. After the ablation, the connector3is switched to connect to the external mapping device, and the first electrode22ais used for mapping again. It can be understood that the mapping and ablation can be carried out alternately according to the actual situation.

In addition, for a structure with the driving member4in this embodiment, the driving member4can be manipulated to adjust the degree of expansion of the support frame21, so as to be well attached to the human tissue.

SECOND EMBODIMENT

An ablation device according to this embodiment has the following differences from that in the first embodiment. Referring toFIGS.2to4, in this embodiment, the bearing rod211of the support frame21helically extends from the proximal end to the distal end.

The helical shape of the bearing rod211can be formed by cutting and heat setting, or by other feasible technical means.

The proximal end of the bearing rod211is deflected from its distal end deflected by a preset angle a in the circumferential direction. Preferably, the preset angle a ranges from 30 degrees to 70 degrees.

The helical angle (i.e., the angle of twist) of the bearing rod211at different positions may be different. Particularly, the bearing rod211has an intermediate position between its proximal end and distal end, and the helical angle of the bearing rod211at the intermediate position is greater than the helical angle at its proximal end or distal end. That is, the bearing rod211does or does not deflect circumferentially at a small angle at its proximal end and distal end while extending in the axial direction, but the bearing rod211deflects circumferentially at a large angle at the intermediate position while extending in the axial direction. Preferably, the helical angle of the bearing rod211gradually decreases from the intermediate position to the proximal end of the bearing rod211or the distal end of the bearing rod211.

It is to be understood that the intermediate position refers to a non-end position of the bearing rod211, and may not particularly refer to a specific position.

In a preferred embodiment, the helical angles of the bearing rod211at various positions are symmetrically distributed on both sides of the intermediate position. When viewed from a direction shown inFIG.3, the projection of the bearing rod211on a plane perpendicular to the axis L of the outer tube1is symmetrical. As shown inFIG.3, the projection of the bearing rod211has a shape that is roughly defined by two straight line segments with an included angle a and an arc connected between the two straight line segments. In other embodiments (not shown), the projection of the bearing rod211may further have a shape that is an ellipse, an arc or other symmetrical geometric shapes.

The plurality of bearing rods211of the support frame21are evenly distributed at the circumferential position of the driving member4. The projections of two adjacent bearing rods211on a plane perpendicular to the axis L of the outer tube1may partially overlap or not overlap at all.

In this embodiment, the helically extending structure of the bearing rod211can have a longer length of attachment to the target ablation area in the circumferential direction, so that the ablation assembly2has better conformity, and can be closely attached to the target ablation area.

Each bearing rod211is provided with a plurality of electrodes22spaced apart from each other along the axial direction. For the plurality of bearing rods211, the plurality of electrodes22correspond one-to-one in the axial direction and are arranged at intervals in the circumferential direction around the axis L of the outer tube1.

Each electrode22can be used as an ablation electrode or as a mapping electrode by being connected to the first terminal32aof the connector3in a one-to-one correspondence mode. The connector3is not illustrated in the ablation device shown inFIGS.2to4, and the mode of connection of the electrode22with the connector3can be made reference to the description in the first embodiment. In addition, the specific method for the electrode22to implement the ablation function and the mapping function can also be made reference to the description in the first embodiment, and will not be further described here.

THIRD EMBODIMENT

An ablation device according to this embodiment has the following differences from that in the first embodiment. Referring toFIGS.5to7, in this embodiment, the support frame21further includes a locating frame213. A proximal end of the locating frame213is connected to the distal ends of the plurality of bearing rods211, and a distal end of the locating frame213is connected to the distal end of the driving member4. When the support frame21is fully expanded, the radial dimension of the locating frame213is smaller than the radial dimension of a frame body defined by the plurality of bearing rods211. The locating frame213and the plurality of bearing rods211can be formed by integrally cutting and shaping a nickel-titanium tube. The radial dimension of the locating frame213is the dimension of the locating frame213in a direction perpendicular to the axial direction of the driving member4.

In the support frame21, when the bearing rod211is applied with an external force perpendicular to its own axis or inclined to their own axis, the locating frame213can transfer the external force to another bearing rod211adjacent to the bearing rod211applied with the external force, whereby the adjacent bearing rod211is pulled. The bearing rod211has the performance of maintaining its own structure and state, so that an opposite force is formed on the adjacent bearing rod211to buffer or offset the force. The adjacent bearing rod211generates a reaction force perpendicular to the axis or inclined to the axis to confront the external force. In this way, the distance between the adjacent bearing rods211can be maintained, to keep the position of the bearing rod211stable, effectively maintain the stability of the relative positions of the electrodes22on the bearing rod211, prevent the short-circuiting due to contact of the electrodes22with one another when the ablation device is working, effectively avoid the breakdown injury to tissues, and reduce the occurrence of serious adverse complications.

The locating frame213includes a plurality of main rods2131and a plurality of branch rods2132. The plurality of main rods2131are arranged along the circumferential direction of the driving member4. A distal end of each main rod2131is connected to the distal end of the driving member4, and a proximal end of each main rod2131is connected to distal ends of a plurality of branch rods2132. The distal end of each bearing rod211is connected to proximal ends of a plurality of corresponding branch rods2132, and the distal ends of a plurality of branch rods2132connected to the same bearing rod211are connected to different main rods2131. Different bearing rods211connected by the same main rod2131and the plurality of branch rod2132can be connected to each other by the corresponding main rod2131and the corresponding branch rods2132, to distribute the stress on respective bearing rods211. For example, the stress on a single bearing rod211can be distributed onto other bearing rods211connected to the corresponding main rod2131.

The plurality of branch rods2132connected to the same main rod2131have an angle therebetween, so that they can be connected to a plurality of bearing rods211or other branch rods2132respectively.

In this embodiment, it is preferable that the proximal end of each main rod2131is connected with the distal ends of two branch rods213, the two branch rods2132connected to the same main rod2131extend in directions away from each other, and the proximal ends of the two branch rods2132connected to the same main rod2131are connected to the distal ends of two adjacent bearing rods211. Accordingly, the external force applied on a single bearing rod211is transmitted to two adjacent bearing rods211through the branch rods2132. Moreover, when the relative position between the driving member4and the outer tube1is adjusted to drive the support frame21to contract or expand, because two adjacent main rods2131are constrained by two branch rods2132bound together, the branch rods2132pull the main rods2131in the axial direction and the radial direction, so that the deformation of the main rods2131in the radial direction and the axial direction is not too large. This is beneficial to the maintenance of the locating frame213in the shape of a mesh basket, such that when the radial dimension of the support frame21is changed, the ablation device can maintain a good centering effect, and the ablation device can be accurately directed to the periphery of the pulmonary vein ostium when the ablation device is used for circular ablation at the pulmonary vein ostium.

In this embodiment, the plurality of branch rods2132are connected end to end to form a wave-shaped ring structure surrounding the driving member4, the proximal end of each main rod2131is connected to the peak of the wave-shaped ring structure, and the distal end of each bearing rod211is connected to the valley of the wave-shaped ring structure. Therefore, the external force applied onto the bearing rod211can be transmitted through the wave-shaped ring structure defined by these branch rods2132.

Preferably, the joint of the main rod2131and the branch rod2132is bent towards a side away from the driving member4, and the joint of the bearing rod211and the branch rod2132is bent towards a side approaching the driving member4.

In this embodiment, the arrangement of the electrode22and the specific method for the electrode22to implement the ablation and mapping function can be made reference to the description in the first embodiment, will not be repeated here.

FOURTH EMBODIMENT

An ablation device according to this embodiment has the following differences from that in the first embodiment. Referring toFIG.8, in this embodiment, the distal end of the bearing rod211is formed with a backward enclosure portion2113. The backward enclosure portion2113is formed by bending the most distal end of the bearing rod211towards the axis of the driving member4and extending towards the proximal end. The backward enclosure portion2113is connected to the distal end of the driving member4, and the most distal end of the bearing rod211exceeds the distal end of the driving member4in the distal direction. The backward enclosure portion2113defined by the plurality of bearing rods211are each connected to the distal end of the driving member4, and the contour of the support frame21is roughly in the shape of a spherical or cage structure.

Due to the differences in the special structures and anatomical characteristics of mitral isthmus, cavotricuspid isthmus, and left atrium apex, and the influence of physiological activities in the heart environment, the ablation treatment at these sites puts forward higher requirements for stable attachment and ablation. The design of the support frame21in this embodiment has the following advantages. On one hand, because the overall shape of the support frame21is spherical or cage-like, the arc-shaped or spherical structure on the surface of the spherical or cage-like support frame21facilitates the attachment and ablation. Accordingly, the support frame21can be easily attached to and positioned in the target ablation area at any angle. In this manner, the ablation device can be used for dot-and-dash ablation or circular ablation, dot-and-dash ablation at the left atrium apex, mitral isthmus, and tricuspid isthmus, or circular ablation at the pulmonary vein ostium. On the other hand, the structural design of the backward enclosure portion2113enables the distal end of the driving member4to locate inside the axial contour of the bearing rod211, so as to avoid the damage to the atrial tissue caused by a tip formed by the protrusion of the distal end of the driving member4, and well conform to the ablation area in the heart.

The length of the backward enclosure portion2113can be set as required, and thus the shape of the distal end of the support frame21can be changed, to adapt to different target ablation areas. When the driving member4has a tubular structure, the backward enclosure portion2113can be clamped in the tubular structure of the driving member4.

Each bearing rod211is provided with a plurality of electrodes22spaced apart from each other along the axial direction. At least one bearing rod211is provided with the electrode22at its most distal end, whereby the support frame21is provided with the electrode22at its most distal end, so that the ablation device can perform local ablation.

Preferably, the most distal end of each bearing rod211is provided with the electrode22. Preferably, the electrode22at the most distal end and the electrode22adjacent to the electrode22at the most distal end of each bearing rod211are set as the first electrodes22a,and the first electrodes22acan be used for both ablation and mapping.

The specific method for the electrode22to implement the ablation function and the mapping function can also be made reference to the description in the first embodiment, and will not be repeated here.

FIFTH EMBODIMENT

An ablation device according to this embodiment has the following differences from that in the first embodiment. Referring toFIG.9, in this embodiment, the distal end of each bearing rod211of the support frame21is connected to the outer periphery of the driving member4, and the tangent line of the distal end of each bearing rod211is perpendicular to the axis of the driving member4, so that the distal ends of the plurality of bearing rods211are bound together to form a shape with an arc or round structure.

Particularly, the outer periphery of the driving member4is provided with a plurality of insertion holes41, and each insertion hole41is correspondingly inserted with the distal end of one bearing rod211, such that each bearing rod211is connected into each insertion hole41in a one-to-one correspondence mode. The end of the bearing rod211connected to the driving member4is the most distal end of the bearing rod211, and the most distal end of the driving member4is flatly smoothly or circularly smoothly connected with the most distal ends of the bearing rods211.

In this structure, the distal end of the ablation device also has no protruding tip, to avoid the damage to the atrial tissue and well conform to the ablation area in the heart.

In this embodiment, the arrangement of the electrode22and the specific method for the electrode22to implement the ablation and mapping function can be made reference to the sescription in the first embodiment, will not be repeated here.

SIXTH EMBODIMENT

An ablation device according to this embodiment has the following differences from that in the fifth embodiment. Referring toFIG.10, the driving member4includes a driving rod43and a joint44arranged at the distal end of the driving rod43. The bearing rods211are each connected to the outer periphery of the joint4, the tangent line of the distal end of bearing rod211is substantially perpendicular to the axis of the joint44, and a distal end of the joint44is approximately tangent to or forms a relatively circularly smooth transition with the distal ends of the plurality of bearing rods211.

A distal end surface of the joint44and a distal end surface of the support frame21are roughly on the same tangent plane, and the contour of the support frame21is roughly of a spherical or cage-like shape. Therefore, the support frame21can be attached stably as a whole, makes the ablation feasible at any angle, and is well applicable to the dot-and-dash ablation of the atrial wall, the mitral isthmus, and the tricuspid isthmus, to achieve the goal of rapid, efficient and high-quality ablation in the whole process.

The joint44can be used as an electrode with mapping and ablation performance, such as an ablation electrode or a mapping electrode, so as to fully improve the usability of the joint44, and systematically enhance the usability of the ablation device. When the joint44is used as an ablation electrode, since the distal end surface of the joint44is approximately tangent to or form a relatively circularly smooth transition with the distal ends of the plurality of bearing rods211, the joint44and the electrodes22arranged at the distal ends of the plurality of bearing rods211can be located on the same ablation spherical surface or ablation cambered surface, to achieve the goal of rapid, efficient and high-quality ablation in the whole process. Further, when the joint44is used as an ablation electrode, it can be used for ablation by radiofrequency ablation or for ablation by pulsed-field ablation. Adjustments can be made by an operator by making a targeted ablation strategy according to different conditions of different patients, to expand the scope of ablation at the lesion position, and meet the ablation requirements of more indications. When the joint44is used as a mapping electrode, the joint44can be solely connected to one conductive terminal32of the connector (not shown) by a wire in a one-to-one correspondence mode. The connector44can be well attached to the surface of the myocardium, which is beneficial to improving the mapping accuracy. The joint44can be used as a mapping electrode alone. Moreover, the joint44can also form a mapping electrode pair with the first electrode22aon the bearing rod211.

In this embodiment, the arrangement method of the electrode22on the bearing rod211and the specific method for the electrode22to implement the ablation function and the mapping function can also be made reference to the description in the first embodiment, which will not be repeated here.

SEVENTH EMBODIMENT

An ablation device according to this embodiment has the following differences from that in the sixth embodiment. Referring toFIG.11, in this embodiment, the support frame21further includes a plurality of support rods215, and each of the support rods215is used for connecting two adjacent bearing rods211. One end of each support rod215is connected to one of the bearing rods211, and the other end is connected to another adjacent bearing rod211. The support rod215extends obliquely, and two ends of the support rod215are spaced in the axial direction of the outer tube1.

The support rod215can restrain the adjacent bearing rods211. In this way, the distance between the adjacent bearing rods211can be maintained, to prevent the bearing rod211from shift when the ablation device works, and avoid short-circuiting due to contact of the electrodes22on adjacent bearing rods211with one another, thus avoiding the occurrence of arcing.

Moreover, the support rods215improve the uniformity in distribution of the bearing rods211in the circumferential direction, making it impossible for the support frame21to twist and deform as a whole, and improving the accuracy and efficiency of ablation and mapping of the ablation device.

In this embodiment, one support rod215is provided at either side of the same bearing rod211, and the support rods215provided at two side of the same bearing rod211both extend distally or proximally to connect another adjacent bearing rods211respectively. That is, the two support rods215provided at two sides of the same bearing rod211extend away from each other.

In this embodiment, the support rods215at two sides of the same bearing rod211are asymmetrical with respect to the bearing rod211, that is, the individual support rods215at two sides of the bearing rod211are connected to the bearing rod211at positions that are axially spaced. First ends of the two support rods215are connected to different positions on the same bearing rod211, and second ends extend in directions away from each other. Such an asymmetric structure is beneficial to improving the stable attachment of the whole spherical structure of the support frame21, the controllability of the arc shape of the spherical structure, and the stability of the whole spherical structure, so that the spherical frame is not prone to deformation.

It is to be understood that the position of the support rod215is not limited. The support rod215can be arranged at a middle position of the bearing rod211, at a distal position of the bearing rod211, or at a proximal position of the bearing rod211.

In this embodiment, the arrangement method of the electrode22on the bearing rod211and the specific method for the electrode22to implement the ablation function and the mapping function can also be made reference to the description in the first embodiment, which will not be repeated here.

EIGHTH EMBODIMENT

An ablation device according to this embodiment has the following differences from that in the seventh embodiment. Referring toFIG.12, in this embodiment, the support rods215at two sides of the same bearing rod211are arranged symmetrically with respect to the bearing rod211.

In this structure, as observed from the whole outer periphery of the support frame21, the support rods215arranged between any two bearing rods211in the plurality of bearing rods211form a ring structure of substantially continuous V shapes or W shapes. The ring structure enables the plurality of support rods215to support and abut against one other, thereby constraining each bearing rod211in the axial direction and the circumferential direction, and improving the stability of the shape of the support frame21. This is beneficial to improving the accuracy of ablation and mapping.

In this embodiment, the arrangement method of the electrode22on the bearing rod211and the specific method for the electrode22to implement the ablation function and the mapping function can also be made reference to the description in the first embodiment, which will not be repeated here.

Although the present invention has been described with reference to several exemplary embodiments, it should be understood that the terminology used is illustrative and exemplary rather than limiting. Since the present invention can be implemented in various forms without departing from the spirit or essence of the present invention, it should be understood that the above-mentioned embodiments are not limited to any of the foregoing details, but should be broadly interpreted within the spirit and scope defined by the appended claims. Therefore, all changes and modifications that fall within the scope of the claims or their equivalents are intended to be covered by the appended claims.