CN219579013U - Pulse ablation catheter and pulse ablation system - Google Patents

Abstract

The utility model discloses a pulse ablation catheter and a pulse ablation system, and belongs to the technical field of pulse ablation. The pulse ablation catheter can be effectively abutted against target tissues, and the pulse ablation effect is optimized. The pulse ablation catheter includes: the handle, the proximal tube body and the annular tube section are connected in sequence. Wherein, the annular pipe section includes: a flexible tube, a support member, and an electrode. The flexible pipe is connected with the lower part of the proximal pipe body; a support member disposed within the flexible tube for supporting the flexible tube for helical bending into a helical loop in a direction away from the proximal tube body; electrodes are disposed on the flexible tube for receiving pulsed ablation signals to generate pulsed ablation electric fields.

Description

Pulse ablation catheter and pulse ablation system

Technical Field

Relates to the technical field of pulse ablation, in particular to a pulse ablation catheter and a pulse ablation system.

Background

Atrial fibrillation is one of the most common clinical arrhythmic diseases, and its morbidity and mortality increases year by year. Among them, thromboembolic complications are the main cause of death and disability of atrial fibrillation, and cerebral stroke is the most common manifestation type. In recent years, the development of an electrophysiological center is rapid, and the catheter ablation technology is widely applied to paroxysmal atrial fibrillation with severe frequent symptoms and continuous atrial fibrillation treatment accompanied with high risk of cerebral apoplexy. The catheter ablation technology is an ablation technology for isolating the pulmonary veins and the left atrium through radial skin puncture, and has the advantages of radical treatment of atrial fibrillation and no need of taking antiarrhythmic drugs for life compared with drug treatment.

The ablation techniques now commonly used can be divided into conventional radiofrequency ablation, cryoablation and emerging pulsed ablation. Radio frequency ablation is usually in a point-to-point mode, and tissue target cells are necrotized by heating, so that tissue electric signals are isolated, and the method is suitable for arrhythmia such as atrial fibrillation, atrial flutter and the like formed by pulmonary veins or pulmonary veins. However, the application of radio frequency energy to the target tissue site has an effect on non-target tissue. For example, application of radio frequency energy to atrial wall tissue may cause esophageal or phrenic nerve damage in the vicinity of the heart, and the longer the radio frequency ablation treatment time, further increasing the likelihood of damage to non-target tissue or the risk of tissue crusting, further increasing the likelihood of embolism. Cryoablation utilizes endothermic vaporization of liquefied refrigerant to substantially reduce ambient temperature. At present, the cryoballoon ablation has better adhesion between the balloon and the pulmonary vein port, so that a continuous and complete annular ablation range can be formed, and the conduction of tissue signals can be isolated by one or more ablations, so that the treatment time is shortened. However, cryoballoon ablation has a high incidence of damage to the phrenic nerve and there is a certain probability of esophageal damage and pulmonary vein stenosis.

Pulsed electric field ablation is an emerging ablation therapy that involves applying a pulsed electric field to target tissue through a pulsed ablation catheter to ablate lesions. In the ablation process, nanosecond micro-holes are generated on the cell membrane through the action of a pulse electric field, so that electroporation is realized. Compared with smooth muscle and nerve cells, the threshold value of the myocardial cells to the pulsed electric field is the lowest, so that the myocardial cells are necrotized first in the process of ablation of the pulsed electric field. Unlike conventional thermal effect-based ablation methods, pulsed electric fields are capable of selectively ablating cardiac tissue while preserving vascular, neural and pericardiac tissue. In addition, the pulse electric field carries out irreversible electroporation ablation on myocardial tissue, heat energy conduction is not needed, the ablation process is efficient and rapid, and the ablation time is obviously shortened. Accordingly, there is a need to provide an ablation catheter that supports pulsed electric field ablation.

Disclosure of Invention

The utility model aims to overcome the defect that radio frequency ablation and cryoablation in the prior art have great damage to non-focal tissues, and provides a pulse ablation catheter and a pulse ablation system.

The utility model solves the technical problems by the following technical scheme:

in a first aspect, embodiments of the present utility model provide a pulse ablation catheter, comprising: the handle, the proximal tube body and the annular tube section are connected in sequence; the annular tube section includes:

a flexible tube connected to the proximal tube body;

a support member disposed within the flexible tube for supporting the flexible tube to be helically bent into a helical loop in a direction away from the proximal tube body;

and the electrode is arranged on the flexible tube and is used for receiving the pulse ablation signal to generate a pulse ablation electric field.

In one embodiment, the support member supports the flexible tube in a helical bend in a direction away from the proximal tube body into at least two helical rings that are coaxially distributed.

In one embodiment, the outer diameter of the helical ring increases gradually in a direction away from the proximal tube; or alternatively

The outer diameter of the spiral ring gradually decreases along the direction away from the proximal tube body; or alternatively

The flexible tube comprises a first ring section, a straight section and a second ring section which are distributed along the direction far away from the proximal tube body, wherein the first ring section and the second ring section are coaxially distributed, and the straight section is axially distributed along the first ring section and is connected with the first ring section and the second ring section.

In one embodiment, the annular tube section is linear when subjected to an external force.

In one embodiment, a plurality of the electrodes are equally spaced on the flexible tube; or alternatively, the process may be performed,

the spacing between adjacent electrodes is divided into a first spacing and a second spacing, and the first spacing is smaller than the second spacing.

In one embodiment, the proximal tube body includes a tip tube connected to the annular tube segment, the tip tube having a second lumen that accommodates the flexible tube;

a positioning assembly is also disposed in the second lumen, the positioning assembly being configured to determine a position of the pulse ablation catheter within the target under examination.

In one embodiment, the pulsed ablation catheter further comprises a guide,

a third inner cavity is further formed in the tail end pipe of the proximal pipe body, the third inner cavity is used for accommodating the guide piece, and the guide piece extends out of the proximal pipe body from the third inner cavity and is arranged beyond the annular pipe section.

In one embodiment, the proximal tube further comprises a flexible bendable tube connected to an end of the distal tube remote from the flexible tube and forming a mounting cavity;

the pulse ablation catheter further comprises a stay wire arranged in the mounting cavity, and the stay wire is fixedly connected with the flexible bendable pipe and used for driving the flexible bendable pipe to bend under the action of external force.

In one embodiment, the flexible, bendable tube is further formed with a fourth lumen, the fourth lumen being in communication with the second lumen and the third lumen,

the pulse ablation catheter also has an electrode lead electrically connected to the electrode, the electrode lead extending from the fourth lumen to the second lumen, and the guide extending from the fourth lumen to the third lumen.

In a second aspect, embodiments of the present utility model provide a pulse ablation system comprising a pulse device, and a pulse ablation catheter as provided in the first aspect above,

the pulse device is electrically connected with the electrode in the pulse ablation catheter and is used for outputting pulse ablation signals to the electrode.

In one embodiment, the pulse device comprises:

the impedance detection assembly is electrically connected with the electrode and is used for outputting a detection signal to the electrode so as to determine the impedance of the current environment of the electrode;

the electrode state determining component is electrically connected with the impedance detecting component and is used for determining the state of the electrode according to a preset threshold value and the impedance acquired by the impedance detecting component, and the state comprises the following steps: the open state, the short state, and the inter-electrode distance are smaller than a preset value.

The utility model has the positive progress effects that:

according to the pulse ablation catheter provided by the embodiment of the utility model, the flexible tube is in a spiral ring shape through the supporting member, so that the electrode on the flexible tube is easier to effectively lean against the target tissue, and the pulse ablation effect is ensured. In addition, the structure of a plurality of spiral rings can bear more electrodes, the pulse ablation effect is improved through the cooperation of different electrodes, and the treatment time is saved.

Drawings

FIG. 1 is a schematic diagram of a pulse ablation catheter shown in accordance with an exemplary embodiment;

FIG. 2 is a schematic illustration of a configuration of a ring segment shown in accordance with an exemplary embodiment;

FIG. 3A is an isometric view of a support member shown according to an exemplary embodiment;

FIG. 3B is a front view of the support member according to FIG. 3A;

FIG. 3C is a schematic illustration of a ring segment within an ablated subject, according to an exemplary embodiment;

FIG. 4A is an isometric view of a flexible tube shown according to another exemplary embodiment;

FIG. 4B is a front view of the flexible tube according to FIG. 4A;

FIG. 4C is a schematic illustration of a ring segment within an ablated subject, according to another exemplary embodiment;

FIG. 5A is an isometric view of a flexible tube shown according to another exemplary embodiment;

FIG. 5B is a front view of the flexible tube according to FIG. 5A;

FIG. 5C is a schematic illustration of a ring segment within an ablated subject, according to another exemplary embodiment;

FIG. 6 is a schematic view of a ring segment within an ablated subject, according to another exemplary embodiment;

FIGS. 7A and 7B are electrode profiles shown according to various exemplary embodiments;

FIG. 8 is a schematic diagram illustrating a structure at an end tube according to an exemplary embodiment;

FIG. 9A is a radial cross-sectional view of an end tube shown according to an exemplary embodiment;

FIG. 9B is a schematic illustration of the connection of the end tube and the annular tube segment shown according to an exemplary embodiment;

FIG. 9C is a schematic view illustrating a use state of a pulse ablation catheter according to an example embodiment;

FIG. 10A is a specific block diagram of a pulse ablation catheter shown according to an example embodiment;

FIG. 10B is a schematic view illustrating a use state of a pulse ablation catheter according to another example embodiment;

FIG. 11A is a radial cross-sectional view of a flexible, pliable tube shown according to an example embodiment;

FIG. 11B is an axial cross-sectional view of a flexible, bendable pipe shown according to an example embodiment;

FIG. 12A is a radial cross-sectional view of a flexible, pliable tube shown according to an example embodiment;

FIG. 12B is an axial cross-sectional view of a flexible, bendable pipe shown according to an example embodiment;

13A, 13B and 13C are schematic diagrams of pulsed electric field profiles shown according to various exemplary embodiments;

14A, 14B and 14C are schematic diagrams of pulse ablation foci shown according to various exemplary embodiments;

FIG. 15 is a schematic diagram of a pulse ablation system shown according to an example embodiment;

FIG. 16 is a block diagram of a pulse device shown according to another example embodiment;

fig. 17 is a schematic diagram illustrating electrode segment impedance detection according to an exemplary embodiment.

In the above figures, the meaning of the individual reference numerals is as follows:

100. a ring tube segment, 100x, in a direction away from the proximal tube body; 110. a flexible tube 110a, a first helical ring 110b, a second helical ring 110c, a third helical ring; 111. a first lumen; 120. an electrode 120a, an ablation electric field 121, a first electrode 122, a second electrode 123, a third electrode; 124. a fourth electrode; 1214. a fourteenth electrode; 130. a support member, 131, a first ring segment, 132, a straight segment, 133, a second ring segment; 140. an electrode lead; 150. a protective layer;

200. a proximal tube body 210, a main tube; 220. a flexible bendable tube 221, a first mounting cavity 222, a second mounting cavity 223, a third mounting cavity 224, a fourth inner cavity 224a, a wire cavity 224b, a guide cavity; 230. a terminal tube 231, a second inner cavity 232, a third inner cavity 241, a first positioning electrode 242, a second positioning electrode 243, a magnetic field sensor 250, a stay wire welding ring 260 and a connecting piece;

300. a handle 310, an electrode socket 320, an adjusting component 331, a first pull wire 332, a second pull wire 333 and a third pull wire;

400. a guide 410, a balloon;

500. a pulse device 510, an impedance detection component, 520, an electrode state determination component;

600. a detection device;

700. an ablation stove;

800. a sheath;

900. the target tissue.

Detailed Description

The utility model is further illustrated by means of the following examples, which are not intended to limit the scope of the utility model.

Example 1

The embodiment of the utility model provides a pulse ablation catheter which can be effectively attached to target tissues and improves the pulse ablation effect. Fig. 1 is a schematic structural view of a pulse ablation catheter shown according to an exemplary embodiment. As shown in fig. 1, the pulse ablation catheter includes a ring tube segment 100, a proximal tube body 200, and a handle 300 connected in sequence.

Fig. 2 is a schematic structural view of a ring segment shown according to an exemplary embodiment. Referring to fig. 1 and 2, the ring segment 100 includes a flexible tube 110, an electrode 120 disposed on the flexible tube 110, and a support member 130 disposed within the flexible tube 110.

The flexible tube 110 has high insulating properties and biocompatibility, and flexibility is good enough to accommodate complex structures in tissue. Alternatively, flexible tube 110 is made of polyether amide (Pebax), polyurethane (PU), or the like. The flexible tube 110 has a first lumen 111, and the support member 130 is disposed in the first lumen 111. The support member 130 is used to shape the flexible tube 110. Specifically, the support member 130 has a three-dimensional "tower" or "inverted tower" type structure when not subjected to an external force. Under the action of the support member 130, the flexible tube 110 is helically bent into a helical loop in a direction away from the proximal tube body 200. Illustratively, the flexible tube 110 is helically bent into at least two coaxially distributed helical rings, such as into 1-5 coaxially distributed helical rings. As shown in fig. 2, the flexible tube 110 is helically bent in a direction 100x away from the proximal tube body to form 3 first helical loops 110a, second helical loops 110b, and third helical loops 110c. Similarly, the support member 130 is spirally curved, wherein the pitch of the spiral ring formed by the support member 130 is 2-8 mm, the minimum outer diameter of the plurality of spiral rings is 9-21 mm, and the maximum outer diameter of the plurality of spiral rings is 25-30 mm.

The flexible tube 110 is made to take a spiral ring shape by the support member 130, in this way, the electrode 120 on the flexible tube 110 is more easily and effectively abutted against the target tissue, ensuring the pulse ablation effect. In addition, the structure of the spiral rings can bear more electrodes 120, the pulse ablation effect is improved through the cooperation of different electrodes 120, and the treatment time is saved.

In one example, fig. 3A is an isometric view of a support member shown according to an example embodiment, and fig. 3B is a front view of the support member shown according to fig. 3A. As shown in fig. 3A and 3B, the outer diameter of the helical ring formed by the support member 130 gradually decreases in a direction 100x away from the proximal tube. At this time, the support member 130 causes the flexible tube 110 to be spirally bent into a "tower" type structure.

Fig. 3C is a schematic diagram illustrating a ring segment within an ablated subject, according to an exemplary embodiment. As shown in fig. 3C, the flexible tube 110 and support members (not shown) in the ring segment 100 take on the tower configuration shown in fig. 3A. At this point, the flexible tube 110 maintains the tower structure in apposition to the target tissue 900.

In one example, fig. 4A is an isometric view of a flexible tube according to another example embodiment, and fig. 4B is a front view of the flexible tube according to fig. 4A. As shown in fig. 4A and 4B, the outer diameter of the helical ring formed by the support member 130 gradually increases in a direction 100x away from the proximal tube. At this time, the support member 130 causes the flexible tube 110 to be spirally bent into an "inverted tower" type structure.

In this example, the ring segment 100 requires a change in the "inverted tower" configuration of the flexible tube 110 when in use. Fig. 4C is a schematic view of a ring segment within an ablated subject, according to another exemplary embodiment. At this time, the flexible pipe 110 and the supporting member (not shown) in the annular pipe section 100 adopt an inverted tower structure shown in fig. 4A. When the annular tube segment 100 is extended into the vicinity of the target tissue, it is required to move further toward the target tissue such that the outer diameter of the helical loop formed by the support members gradually decreases in a direction 100x away from the proximal tube body, i.e., the support members and flexible tube 110 deform from an "inverted tower" type configuration to a "tower" type configuration. In this way, the electrode 120 on the flexible tube 110 is effectively conformed to the target tissue 900.

In one example, fig. 5A is an isometric view of a flexible tube shown according to another example embodiment, and fig. 5B is a front view of the flexible tube shown according to fig. 5A. As shown in fig. 5A and 5B, the supporting member 130 has a segmented structure, and specifically includes a first ring segment 131, a straight segment 132 and a second ring segment 133, which are distributed in a direction away from the proximal tube, the first ring segment 131 and the second ring segment 133 are coaxially distributed, and the straight segment 132 is distributed along an axial direction of the first ring segment 131 and is connected to the first ring segment 131 and the second ring segment 133. Wherein the outer diameter of the first ring segment 131 is greater than the outer diameter of the second ring segment 133 in such a way that the multi-turn ring-shaped tube segment 100 is more accessible to the target tissue.

Fig. 5C is a schematic view of a ring segment within an ablated subject, according to another exemplary embodiment. As shown in FIG. 5C, in the ablated target body, the flexible tube 110 and support member (not shown) in the annular tube segment 100 assume the segmented configuration shown in FIG. 5A and conform to the target tissue 900.

In the embodiment of the present utility model, the flexible tube 110 and the support member 130 in the multi-turn annular tube 100 have deformation properties and are stretched into a straight line shape when being subjected to an external force. Fig. 6 is a schematic view of a ring segment within an ablated subject, according to another exemplary embodiment. As shown in fig. 6, when the pulse ablation catheter is mated with the sheath 800, the ring segment 100 is stretched into a straight shape by an external force. The straight line shape herein does not strictly limit the shape of the annular tube section 100 to a straight line shape, and a state of being approximately straight is also included. In this manner, the annular tube segment 100 facilitates access to the sheath 800 and also to the body of the target to be ablated. When the external force is removed, the annular tube segment 100 returns to the spiral curved shape again based on the shape memory characteristics of the support member.

Referring again to fig. 2, in order to improve the insulation performance of the support member 130 and reduce the friction of the support member 130 with other components (e.g., electrode wires) within the flexible tube 110, a protective layer 150 (e.g., an insulating coating, or an insulating tubing) is coated on the outer surface of the support member 130. Alternatively, the material of the protective layer 150 is polyimide, polytetravinyl chloride, or the like.

In an embodiment of the present utility model, at least two electrodes 120 are provided on the flexible tube 110, and optionally, 5 to 30 electrodes are provided on the flexible tube 110. Fig. 7A and 7B are electrode profiles shown according to various exemplary embodiments, as shown in fig. 7A, a plurality of electrodes 120 are equally spaced on a flexible tube 110, and a spacing H between adjacent electrodes 120 is 3-5 mm. As shown in fig. 7B, the plurality of electrodes 120 are non-equally spaced on the flexible tube 110. Specifically, the pitch of the adjacent electrodes 120 is divided into a first pitch and a second pitch, and the first pitch is smaller than the second pitch. As an example, electrodes 120 are distributed on flexible tube 110 in electrode pairs. Specifically, the first electrode 121 and the second electrode 122 are one electrode pair, the third electrode 123 and the fourth electrode 124 are one electrode pair, and so on. Wherein, the distance between two electrodes in the electrode pair is the first distance H1. For example, the pitches of the first electrode 121 and the second electrode 122, and the pitches of the third electrode 123 and the fourth electrode 124 are both the first pitch H1. The electrodes of adjacent electrode pairs are at a second pitch H2, for example, the second electrode 122 and the third electrode 123 are at a second pitch. Wherein H1 is 1-3 mm, H2 is 3-5 mm.

During pulse ablation, an intracardiac signal needs to be mapped through an electrode pair (e.g., first electrode 121 and second electrode 122 as examples). The smaller spacing of the first electrode 121 and the second electrode 122 can improve the accuracy of intracardiac signal mapping. In this case, during the pulse discharge, the first electrode 121 and the second electrode 122 are connected in series as the same polarity to participate in the discharge, so as to satisfy the requirement of the inter-electrode distance.

In the embodiment of the present utility model, the electrode 120 is an electrode ring sleeved on the flexible tube 110, and the electrode material may be platinum iridium alloy, gold, etc. In addition, the annular tube segment 100 further includes an electrode lead positioned within the first lumen 111 of the flexible tube 110, the electrode lead being electrically connected to the electrode 120 to provide a pulsed ablation signal to the electrode 120.

With continued reference to fig. 1, the handle 300 is for grasping by an operator, and the proximal tube 200 is for connecting the handle 300 to the annular tube segment 100 and serves to support the annular tube segment 100 for delivery of the annular tube segment 100 to a target tissue of an ablated target.

The handle 300 is provided with an electrode socket 310 and an adjusting component 320, wherein the electrode socket 310 is electrically connected with the electrode 120 through a wire and is used for being electrically connected with external pulse equipment so as to transmit pulse ablation signals to the electrode 120. An adjustment assembly 320 (e.g., a knob as shown in fig. 1) is used to cooperate with a pull wire disposed inside the pulsed ablation catheter to control bending of the ring segment 100 such that the electrode 120 on the ring segment 100 effectively conforms to the target tissue.

Proximal tube body 200 includes a main tube 210, a flexible bendable tube 220, and a tip tube 230 connected in sequence. The main body tube 210 is adapted to be coupled to the handle 300 and the tip tube 230 is adapted to be coupled to the ring tube segment 100. The proximal tube body 200 is used to support the annular tube segment 100, and in particular, the outer diameter of the main tube 210 is greater than the outer diameters of the flexible bendable tube 220 and the distal tube 230, which promotes structural stability of the overall proximal tube body 200.

The tip tube 230 is made of a medical polymer material having good flexibility, softness and elasticity, for example: nylon (Pebax), polyester amine (PU), and the like. Fig. 8 is a schematic diagram showing a structure at an end tube according to an exemplary embodiment. As shown in fig. 8, the tip tube 230 is formed with a second lumen 231, the second lumen 231 for receiving the flexible tube 110. Also provided on the tip tube 230 is a positioning assembly for determining the specific location of the pulse ablation catheter within the body of the target to be ablated.

Optionally, the positioning assembly includes a first positioning electrode 241 and a second positioning electrode 242 disposed in the second lumen 231. During pulsed ablation, the positions of the first positioning electrode 241 and the second positioning electrode 242, as well as the electrode 120 on the ring segment 100, are determined by the application of an external electric field. The positioning assembly also includes a magnetic field sensor 243 located in the second lumen 231. During pulsed ablation, the position of the magnetic field sensor 243 within the body of the target to be ablated can be determined by the applied magnetic field. Further, the form and position of the annular tube segment 100 can be obtained from the positions of the first positioning electrode 241, the second positioning electrode 242, and the electrode 120 positioned by the electric field, and the position of the magnetic field sensor 243 positioned by the magnetic field. Thereby enabling visualization of the annular tube segment 100 and providing an operational basis for subsequent steps of pulse ablation.

In one example, a guide is also provided within the proximal tube 200. Specifically, a guide is provided through the handle 300 and proximal tube 200 and beyond the annular tube segment 100. The guide is brought into contact with the target tissue prior to the ring segment 100 during the pulse ablation process to guide and support further advancement of the pulse ablation catheter.

Fig. 9A is a radial cross-sectional view of a tip tube according to an exemplary embodiment, and fig. 9B is a schematic diagram illustrating the connection of a tip tube and a ring tube segment according to an exemplary embodiment. As shown in fig. 9A and 9B, a third lumen 232 is also provided in the distal tube 230 of the proximal tube 200, the third lumen 232 being disposed in parallel with the second lumen 231 that houses the flexible tube 110. The third lumen 232 is for receiving the guide 400. The guide 400 extends from the third lumen 232 out of the proximal tube 200 and beyond the annular tube segment 100. The guide 400 extends beyond the third lumen 232 toward the intermediate region surrounded by the ring segment 100. In addition, there is a gap between the guide 400 and the third lumen 232 for injecting physiological saline into the body of the target to be ablated, avoiding thrombosis.

Fig. 9C is a schematic view illustrating a use state of the pulse ablation catheter according to an exemplary embodiment. As shown in fig. 9B and 9C, the guide 400 is a guidewire and the portion of the guide 400 beyond the annular tube segment 100 is advanced into the pulmonary vein or branch vein prior to the annular tube segment 100, and the operator can push the impulse catheter along the guide 400 until 100 fully conforms to the target tissue 900.

In addition to a guidewire, the guide 400 may also take the form of an anchoring balloon or a metal mesh balloon. Fig. 10A is a specific structural view of a pulse ablation catheter according to an exemplary embodiment, and fig. 10B is a schematic view of a use state of the pulse ablation catheter according to another exemplary embodiment. As shown in fig. 10A and 10B, the balloon 410 of the guide 400 is positioned beyond the annular tube segment 100, with the balloon 410 first contacting the target tissue 900 in use. Unlike the balloon 410 in the anchoring balloon, which includes a balloon portion disposed beyond the annular tube segment 100, the balloon portion of the metal mesh balloon is capable of receiving a pulsed ablation signal for use as an electrode.

Referring again to fig. 1, the flexible, bendable tube 220 is formed with a mounting cavity to receive a pull wire having one end fixedly connected to the flexible, bendable tube 220 and the other end connected to an adjustment assembly 320 on the handle 300 and controlled by the adjustment assembly 320. The flexible bendable section 220 is controlled to deflect in a single direction or in both directions by the adjustment assembly 320 and the pull wire, thereby bending the ring segment 100.

In one example, flexible bendable tube 220 may enable bi-directional bending. Fig. 11A is a radial cross-sectional view of a flexible, bendable pipe shown according to an example embodiment, and fig. 11B is an axial cross-sectional view of a flexible, bendable pipe shown according to an example embodiment. As shown in fig. 11A and 11B, the flexible bendable pipe 220 is formed with a first mounting chamber 221 and a second mounting chamber 222, and the first mounting chamber 221 and the second mounting chamber 222 are symmetrically distributed with respect to the axial direction of the flexible bendable pipe 220. A first pull wire 331 is disposed in the first mounting chamber 221 and a second pull wire 332 is disposed in the second mounting chamber 222. One ends of the first and second wires 331 and 332 protrude from the mounting cavity 221 to the flexible bendable section 220 and are connected to the flexible bendable section 220 by wire weld rings 250 fixed to ends of the flexible bendable section 220. The other ends of the first and second pull wires 331 and 332 are connected to an adjustment assembly on a handle (not shown in fig. 11A and 11B) for controlled pulling of the flexible bendable section 220 to bend. Specifically, the first pull wire 331 contracts to bend the flexible bendable pipe 220 upward (the orientation shown in fig. 11B), and the second pull wire 332 contracts to bend the flexible bendable pipe 220 downward (the orientation shown in fig. 11B). In this way, the ring segment 100 connected to the proximal tube 200 is brought to bend.

In one example, flexible bendable tube 220 may achieve unidirectional bending. Fig. 12A is a radial cross-sectional view of a flexible, bendable pipe shown according to an example embodiment, and fig. 12B is an axial cross-sectional view of a flexible, bendable pipe shown according to an example embodiment. As shown in fig. 12A and 12B, the flexible bendable pipe 220 is formed with a third mounting chamber 223, and the third mounting chamber 223 is located at one side of the axis of the flexible bendable pipe 220. A third pull wire 333 is provided in the third mounting cavity 223. One end of the third pull wire 333 is fixedly connected to the connector 260 inserted into the third mounting cavity 223 in such a way as to be connected to the flexible bendable section 220. The other end of the third pull wire 333 is connected to an adjustment assembly on the handle (not shown in fig. 12A and 12B) for controlled pulling of the flexible bendable section 220 to bend. Specifically, the contraction of third pull wire 333 causes flexible bendable pipe 220 to bend upward (the orientation shown in fig. 12B). In this way, the ring segment 100 connected to the proximal tube 200 is brought to bend.

In addition, the connector 260 also connects to the support member 130 within the tip tube 230, the support member 130 extending from the connector 260 into the first lumen of the flexible tube 110.

The flexible, bendable tube 220 is also formed with a fourth lumen 224 that communicates with the second lumen of the tip tube and the third lumen.

Alternatively, as shown in fig. 11A, the fourth lumen 224 is a separate lumen, and the electrode lead 140 and the guide 400 are disposed through the fourth lumen 224. Wherein protective sleeves are wrapped around the outside of the electrode lead 140 and the guide 400, respectively, to improve the insulation of the electrode lead 140 and the guide 400. The electrode lead 140 extends from the fourth lumen 224 to the second lumen of the tip tube and the guide 400 extends from the fourth lumen to the third lumen of the tip tube.

Alternatively, as shown in fig. 12A, flexible bendable tube 220 is a multi-lumen tube, and fourth lumen 224 specifically includes guidewire lumen 224a and guide lumen 224b. The lead cavity 224a is for receiving the electrode lead 140. The electrode lead 140 extends from the lead lumen 224a into the second lumen of the tip tube and into the flexible tube interior for electrical connection with the electrode. The guide lumen 224b is configured to receive the guide 400, and the guide 400 extends from the guide lumen 224b into the third lumen of the tip tube and out of the tip tube.

In summary, in the pulse ablation catheter provided by the embodiment of the utility model, the support member 130 makes the flexible tube 110 have a ring structure, so that the flexible tube 110 can bear a greater number of electrodes 120, and multiple treatment modes are realized by matching different electrodes 120.

Alternatively, a monopolar discharge mode is employed, i.e., the electrodes 120 on the ring segment 100 are of the same polarity to form an ablative electric field with the backplate of the body surface being ablated.

Alternatively, a bipolar discharge pattern is employed, i.e., an ablative electric field is formed between electrodes 120 on the ring segment 100. Specifically, a pair of electrodes 120 on the ring segment 100 is selected for discharge, or electrode segments of several pairs of electrodes 120 are selected for discharge, or, in the case of a pulse ablation catheter comprising a metal mesh balloon, several electrodes 120 are selected to participate in the discharge with the metal mesh.

Also, the positive and negative properties of the electrode 120 have a variety of options. Fig. 13A, 13B, and 13C are schematic diagrams showing pulse electric field distribution according to different exemplary embodiments.

As shown in fig. 13A, adjacent electrodes 120 on flexible tube 110 are of opposite polarity. For example, the first electrode 121 and the third electrode 123 are positive, and the second electrode 122 is negative. At this time, the ablation electric field 120a formed by each pair of adjacent electrodes 120 has a portion overlapping.

As shown in fig. 13B, the electrodes 120 are arranged in a positive-negative-positive or negative-positive manner. That is, two adjacent electrodes 120 form an electrode group, and the electrical properties of the adjacent electrodes 120 in the adjacent electrode group are the same. For example, the first electrode 121 is positive, the second electrode 122 and the third electrode 123 are negative, and the fourth electrode 124 is positive. At this time, the overlapping portion of the ablation electric field 120a formed by each pair of electrode groups is reduced.

As shown in fig. 13C, the polarity of the electrodes 120 on adjacent spiral rings is reversed. For example, the electrode 120 on the first spiral ring 110a is positive and the electrode 120 on the second spiral ring 110b is negative. At this time, the ablation electric field 120a is formed by the cooperation of the electrodes 120 on the different spiral rings.

And, based on different implementations of the annular tube segment 100, the pulsed ablation catheter is capable of achieving similar ablation widths and ablation depths within the target volume being ablated. Fig. 14A, 14B, and 14C are schematic diagrams of pulse ablation foci shown according to various exemplary embodiments. When the annular tube section adopts the supporting member shown in fig. 3A, and the pulse ablation catheter has a metal mesh ball, an ablation focus 700 formed by the pulse ablation catheter is shown in fig. 14A. When the annular tube section is used with the support member shown in fig. 4A, the pulse ablation catheter results in an ablation focus 700 as shown in fig. 14B, where the flexible tube 110 is pushed from the inverted tower configuration to the tower configuration. When the annular tube section is used with the support member shown in fig. 5A, a pulse ablation catheter results in an ablation focus 700 as shown in fig. 14C. According to fig. 14A, 14B and 14C, the ring segment 100 can achieve a good ablation width L and ablation depth D, i.e. ensure a good ablation effect.

In summary, according to the pulse ablation catheter provided by the embodiment of the utility model, the support member 130 makes the flexible tube 110 take on a spiral ring shape, so that the electrode 120 on the flexible tube 110 is more easily and effectively abutted against the target tissue, and the pulse ablation effect is ensured. In addition, the structure of the spiral rings can bear more electrodes 120, the pulse ablation effect is improved through the cooperation of different electrodes 120, and the treatment time is saved.

Example 2

The embodiment of the utility model provides a pulse ablation system. Fig. 15 is a schematic diagram of a pulse ablation system shown according to an example embodiment. As shown in fig. 15, the pulse ablation system includes a pulse device 500 and a pulse ablation catheter. The pulse device 500 is electrically connected to the electrode 120 in the pulse ablation catheter for outputting a pulse ablation signal to the electrode.

The pulse ablation signal received by the pulse ablation catheter provided by the embodiment of the utility model is an electric signal of high-frequency high-voltage short pulse. The voltage of the pulse ablation signal is 500-2000V, and the pulse width is 0.1-50 mu s. The pulse energy needs to be released during the safety period of the cardiac cycle. The pulse ablation system further includes a detection device 600, the detection device 600 being electrically connected to the pulse device 500. When the detecting device 600 detects the R wave for 50 to 200ms, the pulse device 500 releases the pulse ablation signal to the pulse ablation catheter.

Fig. 16 is a block diagram of a pulse device shown according to another example embodiment. As shown in fig. 16, the pulse apparatus 500 includes an impedance detection component 510 and an electrode state determination component 520.

The impedance detection component 510 is electrically connected to the electrode 120, and is configured to output a detection signal to the electrode 120 to determine an impedance of a current environment of the electrode 120.

The low voltage detection signal is released for impedance detection before the pulse device 500 releases the pulse ablation signal. The detection signal is a high-frequency low-voltage pulse signal, the voltage is 10-100V, the pulse width is 0.1-50 us, and the pulse structure form is the same as or similar to the waveform form of the pulse ablation signal.

Optionally, the impedance sensing component 510 obtains the impedance of the environment in which the current electrode 120 is located from the voltage applied to the electrode 120 and the current through the electrode 120. When the electrode 120 is suspended in blood, the impedance sensing assembly 510 obtains a blood impedance, and when the electrode 120 is in contact with the target tissue, the impedance sensing assembly 510 obtains a contact impedance. The contact resistance may be used as an evaluation parameter for evaluating the degree of abutment of the annular tube segment 100 with the target tissue.

The electrode state determining component 520 is electrically connected to the impedance detecting component 510, and is configured to determine the state of the electrode according to the preset threshold and the impedance obtained by the impedance detecting component, where the state includes: the open state, the short state, and the inter-electrode distance are smaller than a preset value.

Specifically, when the impedance value detected by the impedance detection module 510 is far greater than the blood impedance, it is determined that the ablation electrode is in an open state. For example, a preset threshold value greater than the impedance value of blood is set according to the requirements, and when the detected impedance value is greater than the preset threshold value, the ablation electrode is indicated to be in an open state. At this time, the pulse device 500 outputs a first warning message (e.g., a text warning or a voice warning) to warn that the pulse ablation catheter has an open circuit, and no pulse ablation signal is output to the pulse ablation catheter.

When the impedance value detected by the impedance detection module 510 is smaller than the first set threshold value, it is determined that the electrode spacing is smaller than the preset value. Illustratively, pulse ablation is performed in a segmented discharge fashion, where the polarity of the electrodes on each segment of flexible tube 110 is the same and the polarity of the electrodes on adjacent segments is opposite. Fig. 17 is a schematic diagram illustrating electrode segment impedance detection according to an exemplary embodiment. As shown in fig. 17, the first electrode 121 on the first spiral ring 110a is closer to the fourteenth electrode 1214 on the third spiral ring 110c, resulting in a smaller impedance value detected by the impedance detection module 510. This may be the case because the annular tube segment does not form a tower within the body of the target being ablated resulting in a closer distance between the electrodes on the different spiral rings. At this time, the pulse device 500 outputs a second prompt (e.g., a text prompt or a voice prompt) to alert that the electrodes in the pulse ablation catheter are too close or in contact, and no pulse ablation signal is output to the pulse ablation catheter.

For example, as a special case where the impedance value is smaller than the first set threshold, the impedance value detected by the impedance detection module 510 is smaller than the second set threshold, and the second set threshold is smaller than the first set threshold, at this time, it is determined that the electrode of the pulse ablation catheter is in a short-circuited state. For example, the electrodes are in direct contact, or there is a short circuit in the circuitry within the pulse ablation catheter. At this time, the pulse device 500 outputs a third warning message (e.g., text warning or voice warning) to alert the pulse ablation catheter to the presence of a short circuit, and no pulse ablation signal is outputted to the pulse ablation catheter.

In summary, the pulse ablation system provided by the embodiment of the utility model combines the physiological structural characteristics of the pulmonary veins and the technical characteristics of pulse ablation, and adopts the pulse ablation catheter with the annular tube section to realize effective adhesion with the pulmonary veins. And moreover, the tube body with the ring-shaped structure can bear more electrodes, ablation in different areas is realized through different electrode combinations, and the pulse ablation efficiency is improved. And the impedance monitoring is carried out on the catheter electrode and the equipment state before the pulse energy is released by the pulse equipment, so that the pulse ablation effect can be safely and effectively improved, and the operation time can be saved.

While specific embodiments of the utility model have been described above, it will be appreciated by those skilled in the art that this is by way of example only, and the scope of the utility model is defined by the appended claims. Various changes and modifications to these embodiments may be made by those skilled in the art without departing from the principles and spirit of the utility model, but such changes and modifications fall within the scope of the utility model.

Claims (10)

1. A pulse ablation catheter, the pulse ablation catheter comprising: the handle, the proximal tube body and the annular tube section are connected in sequence; the annular tube section includes:

a flexible tube connected to the proximal tube body;

a support member disposed within the flexible tube for supporting the flexible tube to be helically bent into a helical loop in a direction away from the proximal tube body;

an electrode disposed on the flexible tube for receiving a pulsed ablation signal to generate a pulsed ablation electric field;

the proximal tube body includes a tip tube connected to the annular tube segment, the tip tube having a second lumen for receiving the flexible tube;

a positioning assembly is also disposed in the second lumen, the positioning assembly being configured to determine a position of the pulse ablation catheter within the target under examination.

2. The pulse ablation catheter of claim 1, wherein the support member supports the flexible tube helically bent in a direction away from the proximal tube body into at least two helical loops coaxially distributed.

3. The pulse ablation catheter of claim 2, wherein the spiral ring has an outer diameter that gradually increases in a direction away from the proximal tube body; or alternatively

The outer diameter of the spiral ring gradually decreases along the direction away from the proximal tube body; or alternatively

The flexible tube comprises a first ring section, a straight section and a second ring section which are distributed along the direction far away from the proximal tube body, wherein the first ring section and the second ring section are coaxially distributed, and the straight section is axially distributed along the first ring section and is connected with the first ring section and the second ring section.

4. The pulse ablation catheter of claim 1, wherein the annular tube section is linear in shape when subjected to an external force.

5. The pulse ablation catheter of claim 1, wherein a plurality of the electrodes are equally spaced on the flexible tube; or alternatively, the process may be performed,

the spacing between adjacent electrodes is divided into a first spacing and a second spacing, and the first spacing is smaller than the second spacing.

6. The pulsed ablation catheter of claim 1, further comprising a guide,

a third inner cavity is further formed in the tail end pipe of the proximal pipe body, the third inner cavity is used for accommodating the guide piece, and the guide piece extends out of the proximal pipe body from the third inner cavity and is arranged beyond the annular pipe section.

7. The pulse ablation catheter of claim 6, wherein the proximal tube further comprises a flexible bendable tube connected to an end of the distal tube distal from the flexible tube and forming a mounting lumen;

the pulse ablation catheter further comprises a stay wire arranged in the mounting cavity, and the stay wire is fixedly connected with the flexible bendable pipe and used for driving the flexible bendable pipe to bend under the action of external force.

8. The pulsed ablation catheter of claim 7, wherein the flexible, bendable tube is further formed with a fourth lumen, the fourth lumen in communication with the second lumen and the third lumen,

the pulse ablation catheter also has an electrode lead electrically connected to the electrode, the electrode lead extending from the fourth lumen to the second lumen, and the guide extending from the fourth lumen to the third lumen.

9. A pulse ablation system comprising a pulse device, and a pulse ablation catheter according to any one of claims 1-8,

the pulse device is electrically connected with the electrode in the pulse ablation catheter and is used for outputting pulse ablation signals to the electrode.

10. The pulsed ablation system of claim 9, wherein the pulsed device comprises:

the impedance detection assembly is electrically connected with the electrode and is used for outputting a detection signal to the electrode so as to determine the impedance of the current environment of the electrode;

the electrode state determining component is electrically connected with the impedance detecting component and is used for determining the state of the electrode according to a preset threshold value and the impedance acquired by the impedance detecting component, and the state comprises the following steps: the open state, the short state, and the inter-electrode distance are smaller than a preset value.