WO2023142428A1

WO2023142428A1 - Splined basket ablation catheter capable of being bent bidirectionally

Info

Publication number: WO2023142428A1
Application number: PCT/CN2022/111657
Authority: WO
Inventors: 谭家宏
Original assignee: 上海鑫律通生命科技有限公司
Priority date: 2022-01-26
Filing date: 2022-08-11
Publication date: 2023-08-03

Abstract

A splined basket pulsed field ablation catheter capable of being bent bidirectionally, which comprises an adjustment handle (1), a catheter body (2), and a treatment head (3); the adjustment handle (1) comprises a bend control knob (13), and the bend control knob (13) is connected to two pull wires; the catheter body (2) comprises at least two pull wire cavities which are axially symmetrically distributed; the bend control knob (13) enables a distal end of the catheter body (2) to bend by means of at least two pull wires, thereby enabling the treatment head (3) to achieve bidirectional bending; the treatment head (3) comprises a splined basket having a plurality of splines, wherein each spline comprises at least one annular electrode. The splined basket catheter has a controllable bidirectional bending feature, assisting a doctor in easily reaching four pulmonary veins at different spatial locations; the splined basket catheter fits well with a pulmonary vein antrum by means of complex angle control, up to 10 splines and a high-density electrode arrangement provide an effective high-density pulsed field ablation ring or surface, and the objective of quickly, effectively, and safely isolating a pulmonary vein and treating atrial fibrillation are achieved.

Description

A two-way bendable spline basket ablation catheter

priority statement

This application is a continuation of the Chinese patent (Patent No. CN202210095734.7 and CN202220218952.0) filed on January 26, 2022, and claims priority thereof, the entire contents of which are hereby incorporated by reference.

technical field

The invention relates to the field of medical equipment, in particular to a two-way bendable spline basket ablation catheter.

Background technique

Cardiac ablation has undergone a great deal of innovation and rapid development since it was first performed in 1969. Ablation was first used in patients with supraventricular tachycardia with accessory pathways and WWD syndrome, and today, ablation is also used to treat atrial flutter, atrial fibrillation, and ventricular arrhythmias.

The goal of ablation is to destroy the underlying arrhythmic tissue and create a transmural and continuous permanent lesion. Percutaneous catheter ablation of pulmonary vein (PV) isolation in atrial tissue using radio-frequency ablation (RFA) and cryoablation therapy has become a widely accepted procedure for the treatment of atrial fibrillation (AF). Other energy modalities for catheter ablation include microwaves, high-intensity focused ultrasound, low-intensity collimated ultrasound, lasers, cryogenic energy, and heated saline. Radio-frequency (Radio-frequency, RF) energy is currently the most commonly used energy source. RF creates lesions by resistively heating tissue and subsequently conducting the heat to deeper tissues.

The cornerstone of AF treatment is the isolation of the pulmonary veins in the left atrium. Generally, there are four pulmonary veins, namely the left upper pulmonary vein, left lower pulmonary vein, right upper pulmonary vein, and right lower pulmonary vein. The normal value of the size of the left atrium is 45-55mm, and the four pulmonary veins must be completely isolated in such a small space.

U.S. Patent US20170071665A1 discloses a flexible spinal basket catheter suitable for mapping and/or ablation in the atria having a basket electrode array with two or more position sensor. The catheter includes a catheter body, a basket electrode assembly at a distal end of the catheter body, and a control handle at a proximal end of the catheter body. The basket electrode assembly has a plurality of barbs with electrodes and a dilator adapted to move longitudinally relative to the catheter body to expand and collapse the assembly by extending beyond the proximal portion of the control handle, which can be Push or pull by the control handle. The dilator is also adapted to flex in response to an actuator on the control handle that allows the user to control at least one pull wire extending through the catheter body and the dilator. However, similar to the above-mentioned patented products, only the treatment head can be bent in a small range, which cannot meet the bending requirements of the complex vascular environment. Additionally, the spinal basket catheter is primarily used for mapping rather than ablation.

US Patent US9101734B2 discloses a force-sensing catheter for diagnosis or treatment of blood vessels found in the body or in a body space, the sensing catheter comprises a central strut preferably aligned along its longitudinal axis with a thermoplastic tubular member housed therein thermally bonded. The tubular member preferably has three layers: an inner layer, a braid and an outer layer. One or more semiconductor or metal foil strain gauges are affixed to the central strut to provide bending and torsional force measurements at the distal end of the catheter. This patent measures and controls the bending by setting strain gauges on the support rods, and the structure is relatively complicated.

European patent EP3915477A1 discloses an electrode device for diagnosing cardiac arrhythmia, wherein FIG. 7 is a diagram of the middle part of the catheter shaft deflected by about 360°. The end effector has a first side and a second side. This allows the user to place the first side on the tissue surface, with at least the middle portion (if not the distal portion of the catheter body) generally perpendicular to the tissue surface, and actuate the control handle to deflect the middle deflection portion to achieve various deflections or curvatures radius such that the second side is deflected toward the catheter body. Such positioning may allow the second side to drag the transverse plane of the end effector including the

ring members

1, 2, 3 through the tissue surface when the intermediate portion is deflected. The middle section can be deflected by manipulating the pull wire. However, this patent can only realize the deflection of the middle part of the catheter, and cannot quickly and accurately control the direction of the treatment head.

The current pulsed electric field spline basket catheters at home and abroad cannot be actively adjusted in both directions, and it is difficult to help the catheter reach the vestibule of the pulmonary vein at different angles for treatment, thus increasing the difficulty of the doctor's operation and increasing the risk of surgery. Therefore, how to provide a flexible spline basket ablation catheter with good maneuverability, which is not only suitable for ablation diagnosis and treatment of annular vascular orifices, but also suitable for ablation diagnosis and treatment of non-vascular orifices; it can be used for radiofrequency ablation An ablation system that can be used for pulsed electric field ablation and other situations is a technical problem to be solved urgently by those skilled in the art.

Contents of the invention

In order to achieve the above purpose, the present application provides a two-way bendable spline basket ablation catheter, which is characterized in that it includes an adjustment handle, a catheter body and a treatment head;

The adjusting handle includes a bending control knob, and the bending control knob is connected with 2 pull wires;

The catheter body includes at least two axially symmetrically distributed puller lumens;

The bending control knob bends the distal end of the catheter main body through at least two pull wires, so that the treatment head can be bent in two directions.

The treatment tip includes a spline basket having a plurality of splines, wherein each spline includes at least one ring electrode. Preferably, each spline includes 1 to 5 ring electrodes. The electrodes on the splines can be of equal length or of different lengths. The ring electrode is circular, or oval, or chamfered, or in the middle shape.

Preferably, each spline comprises 2-4 ring electrodes.

Preferably, said spline basket comprises 4-10 splines.

Preferably, the ring-shaped electrodes on the spline are distributed at the distal end of the spline basket, occupying 1/10-2/3 of the entire spline length.

Preferably, the ring electrodes of each spline include one short electrode at the distal end of the spline and one to four long electrodes at the middle and proximal parts.

Preferably, the catheter body is a hollow tubular structure with a guide wire lumen in the middle, and the pull wire lumens are symmetrically distributed in the tube wall along the axial direction.

In one embodiment, a plurality of lumens are evenly distributed in the tube wall of the catheter body, and two of the lumens distributed symmetrically along the axial direction are used as puller lumens.

Preferably, the number of the plurality of lumens is preferably 2-10.

Preferably, the shape of the lumen of the tube wall can be circular, elliptical, or elongated.

Preferably, the bending angle of the treatment head of the ablation catheter and the distal end of the catheter body can be adjusted within the range of 0° to 180°, so that the treatment head can quickly reach the pulmonary vein vestibule or other vein targets at different angles.

In one embodiment, the distal end of the catheter body is a bendable section, and the wall of the bendable section is made of a flexible polymer material with an elastic modulus of less than 1 MPa.

In one embodiment, the bending angle of the treatment head is related to the turning angle of the bending control knob. There are displacement or angle scale marks around the bending control knob, through which the bending angle of the treatment head can be precisely adjusted.

In one embodiment, the adjustment handle is further provided with a friction control module. By pressing or rotating the friction control button so that the friction force between the handle and the pull wire is greater than the tension of the pull wire, the position of the pull wire can be fixed, so that the bending angle of the catheter remains fixed.

Beneficial technical effect of the present invention:

(1) The spline basket catheter of the present invention has the performance of controllable two-way bending, which helps doctors easily reach the four pulmonary veins in different spatial positions, or other vein targets, and makes the spline basket catheter very good through the control of complex angles. Fit the pulmonary vein vestibule or other vein targets to quickly and effectively isolate the pulmonary vein, which not only reduces the X-ray exposure of doctors and patients, but also greatly shortens the entire operation time, improves the efficiency of doctors and interventional catheterization laboratories, and reduces the operation cost risk;

(2) The splines in the spline basket of the present invention are covered with a plurality of annular electrodes, and the spline basket can form umbrella-shaped, elliptical, spherical, flat, and petal-shaped continuous deformations, which are suitable for different ablation sites It can also control multiple electrode pairing combinations of each spline to achieve the effect of adjusting the ablation range, with strong flexibility and wide application range;

(3) When the other electrodes of the spline basket are performing discharge ablation, the ring electrodes at the distal end of each spline can be paired with the electrodes on the adjacent splines to map ECG signals in real time. Once the real-time mapping meets the requirements of ECG interruption , the ablation can be stopped, the damage to the tissue can be minimized, and the safety of ablation can be improved;

(4) The longer ring electrode in each spline can cover the vascular vestibule with different calibers. This design can meet the needs of all patients with a spline basket catheter of one size; the longer electrode itself can be easily Curved to achieve a perfect fit with the surface of the ablated tissue and improve the success rate of ablation;

(5) The spline basket catheter has multiple splines evenly distributed. Under the control of the double bending function, it is convenient to reach the pulmonary vein orifice. The doctor can flexibly push the catheter forward and easily make the far hemisphere of the spline basket close to the vestibule of the pulmonary vein. tissue, so that the ablation energy can be efficiently delivered to the ablation target. At the same time, multiple splines share the overall support force of the spline basket, preventing cardiac perforation and pericardial effusion, and improving the safety and effectiveness of ablation;

(6) There is a scale mark of displacement or angle around the bending control knob of the handle of the present invention, and the bending angle of the treatment head can be precisely adjusted through the scale, which is convenient and quick;

(7) Through the friction control module of the present invention, the bending angle of the treatment head can be fixed, thereby allowing the operator to use the rocker and the deflection tip in a "free" state.

The above description is only an overview of the technical solution of the present application. In order to understand the technical means of the present application more clearly, it can be implemented according to the contents of the description, and in order to make the above and other purposes, features and advantages of the present application more obvious and understandable , the preferred embodiments of the application and accompanying drawings are described in detail below.

According to the following detailed description of specific embodiments of the application in conjunction with the accompanying drawings, those skilled in the art will be more aware of the above and other objectives, advantages and features of the application.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are For some embodiments of the present application, those skilled in the art can also obtain other drawings based on these drawings without creative work, and these are all within the protection scope of the present application. Throughout the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, elements or parts are not necessarily drawn in actual scale.

Figure 1 is a schematic diagram of the overall structure of a bidirectionally bendable spline basket ablation catheter disclosed by the present invention;

Fig. 2 is a schematic structural diagram of the first embodiment of the spline basket of the ablation catheter disclosed in the present invention;

Fig. 3 is a schematic structural diagram of the second embodiment of the spline basket of the ablation catheter disclosed in the present invention;

Fig. 4 is a schematic structural view of the third embodiment of the spline basket of the ablation catheter disclosed in the present invention;

Fig. 5 is a schematic structural view of the fourth embodiment of the spline basket of the ablation catheter disclosed in the present invention.

Fig. 6 is a schematic diagram of the multilayer structure of the main body of the ablation catheter disclosed in the present invention;

Fig. 7 is a schematic diagram of a cross-sectional lumen structure of the main body of the ablation catheter disclosed in the present invention;

Fig. 8 is a schematic structural diagram of the second embodiment of the section lumen of the main body of the ablation catheter disclosed in the present invention;

Fig. 9 is a schematic structural view of the third embodiment of the section lumen of the main body of the ablation catheter disclosed in the present invention;

Fig. 10 is a schematic structural view of the fourth embodiment of the cross-sectional lumen of the ablation catheter body disclosed in the present invention;

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments It is a part of the embodiments of this application, not all of them. In the following description, specific details, such as specific configurations and components, are provided only to help a comprehensive understanding of the embodiments of the present application. Accordingly, those of ordinary skill in the art should recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope and spirit of the application. Also, descriptions of well-known functions and constructions are omitted in the embodiments for clarity and conciseness.

It should be understood that references to "one embodiment" or "the present embodiment" throughout the specification mean that a particular feature, structure or characteristic related to the embodiment is included in at least one embodiment of the present application. Thus, appearances of "one embodiment" or "the present embodiment" in various places throughout the specification do not necessarily refer to the same embodiment. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments.

Furthermore, the application may repeat reference numbers and/or letters in different instances. This repetition is for the purposes of simplicity and clarity and does not in itself indicate a relationship between the various embodiments and/or arrangements discussed.

The term "and/or" in this article is just an association relationship describing associated objects, which means that there may be three relationships, for example, A and/or B, which can mean: A exists alone, B exists alone, and A and B exist simultaneously. In the three cases of B, the term "/and" in this article is to describe another associated object relationship, which means that there can be two relationships, for example, A/ and B, which can mean: there is A alone, and there are two cases of A and B alone , In addition, the character "/" in this article generally indicates that the contextual objects are an "or" relationship.

The term "at least one" in this article is just an association relationship describing associated objects, which means that there may be three relationships, for example, at least one of A and B can mean: A exists alone, A and B exist simultaneously, There are three cases of B alone.

It should also be noted that in this article, relational terms such as first and second etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that these entities or operations Any such actual relationship or order exists between. Moreover, the terms "comprises", "comprises" or any other variation thereof are intended to cover a non-exclusive inclusion.

Accompanying drawing 1 of the present invention introduces a schematic diagram of the overall structure of a bidirectionally bendable spline basket ablation catheter.

Please refer to Figure 1, which shows a two-way bendable spline basket ablation catheter, which includes:

Including adjustment handle 1, catheter body 2 and treatment head 3;

The adjusting handle 1 includes a bending control knob 13 connected with two pull wires; one end of the pulling wires is fixed in the retractable part 12 of the adjusting handle 1 .

The catheter body 2 includes at least two axially symmetrically distributed puller lumens;

The bending control knob 13 bends the distal end 22 of the catheter body 2 through at least two pull wires, so that the treatment head can be bent in two directions.

In one embodiment, the distal end 22 of the catheter body 2 is a bendable segment, and the tube wall of the bendable segment is made of a flexible polymer material with an elastic modulus of less than 1 MPa.

In one embodiment, the bending angle of the treatment head 3 is related to the turning angle of the bending control knob 13 . There may also be scale marks for displacement or angle around the bending control knob 13, through which the bending angle of the treatment head can be precisely adjusted.

In one embodiment, the adjusting handle 1 is also provided with a friction control module 14 . By pressing or rotating the button of the friction control module 14 so that the friction force between the handle and the pull wire is greater than the tension of the pull wire, the position of the pull wire can be fixed, so that the bending angle of the catheter remains fixed.

In one embodiment, the treatment head 3 includes a spline basket with multiple splines, the spline basket includes 4-10 splines, and each spline includes 1-5 ring electrodes. The electrodes on the splines can be of equal length or of different lengths. The ring electrode is circular, or oval, or chamfered, or in the middle shape.

The annular electrodes on the splines are distributed at the far end of the spline basket, occupying 1/10-2/3 of the entire spline length.

The length of the annular electrode is 0.5mm-5mm, the outer diameter is 2F-10F, it is close to the outer wall of the spline, the inner diameter is similar to the spline, and the distance between adjacent electrodes on the same spline is 0.5mm-20mm.

The material of the ring electrode includes but is not limited to metal platinum, platinum alloy, gold, gold alloy, copper, stainless steel, nickel-titanium alloy, titanium alloy, MP35N and a metal composite structure with X-ray imaging components, such as The non-developing body composite structure with X-ray developing coating can also be the composite structure of developing metal powder and polymer.

Preferably, the ring electrodes of each spline include one short electrode at the distal end of the spline and one to two long electrodes at the middle and proximal parts.

In one embodiment, the length of the long electrode is more than 1.5 times, preferably more than 2 times, the length of the short electrode.

In one embodiment, the annular electrodes of each spline include 1-5 short electrodes.

In one embodiment, the distal end 22 of the catheter body 2 is a bendable section, and the elastic modulus of the bendable section is smaller than that of other parts of the catheter body. Preferably, the pipe wall of the bendable section has a hollow structure (such as including a plurality of hollow channels).

Preferably, the bending angle of the treatment head of the ablation catheter and the distal end of the catheter body can be adjusted within the range of 0-180°, so that the treatment head can quickly reach different angles of the pulmonary vein vestibule.

Please refer to accompanying drawing 2, described treatment head 3 comprises a spline basket with 10 splines 33, and the annular electrode of each spline comprises 1 short electrode 342 positioned at the spline distal end and 1 short electrode 342 in the middle. long electrode 341 .

One end of the 10 splines is fixed on the conduit main body nozzle 31, and the other end is fixed on the front end of the hollow push rod 32.

Please refer to accompanying drawing 3, the second embodiment of the spline basket of the ablation catheter, the treatment head 3 includes a spline basket with 8 splines 33, and the ring electrodes of each spline include two ring electrodes , that is, the first ring electrode 351 and the second ring electrode 352 .

One end of the eight splines is fixed on the nozzle 31 of the catheter main body, and the other end is fixed on the front end of the hollow push rod 32 .

Please refer to accompanying drawing 4, the third embodiment of the spline basket of the ablation catheter, the treatment head 3 includes a spline basket with 8 splines 33, and the annular electrode of each spline includes a short electrode 361 , the second electrode 362 , and the third electrode 363 .

Please refer to accompanying drawing 5, the fourth embodiment of the spline basket of the ablation catheter, the treatment head 3 includes a spline basket with 8 splines 33, and the ring electrode of each spline includes four short The ring electrodes are the first ring electrode 371 , the second ring electrode 372 , the third ring electrode 373 and the fourth ring electrode 374 .

The main body of the catheter is composed of a three-layer structure. Accompanying drawing 6 shows the manufacturing method of the main body of the catheter by the heat shrinking method. From the inside to the outside are the heat shrinkable mandrel 21, the inner tube layer 22, the braided layer 23, and the outer tube layer 24. , Heat shrinkable layer 25. After the heat shrinking is completed, the mandrel is taken out, the heat shrinkable layer is peeled off, and the three-layer braided structure of the catheter main body is obtained. Between the inner tube and the braiding layer, a similar heat-shrinking process can also be used to increase the symmetrically distributed drawing wire cavities on both sides, or other cavities.

The material of the mandrel 21 is a stainless steel rod with PTFE coating, PEEK rod, etc.; the material of the inner tube layer 22 is TPU or Pebax, nylon, or polyimide with a smaller friction coefficient and better insulation performance. Amine, FEP, ETFE, PTFE; The braided layer 23 is made of stainless steel braided mesh, or other metal mesh, or high-strength polymer braided mesh; the outer tube layer 24 is made of TPU, Pebax, nylon and other materials; The heat-shrinkable layer 25 is made of heat-shrinkable materials such as FEP and PTFE.

Catheter bodies can also be produced by extrusion methods. That is, first extrude the inner tube layer on the soft mandrel, then weave the braided mesh outside the inner tube layer, then extrude the outer tube layer out of the braided mesh, and grind the outer tube layer to a suitable size.

The catheter body can also be a multi-lumen structure without braiding layer, which can be directly produced by extrusion method.

The pull wire is a stainless steel wire or a nickel-titanium wire, which is fixed to the main body of the catheter near the nozzle 31 .

Referring to FIG. 7 , the main body of the catheter is a hollow tubular structure with a guide wire lumen 202 in the middle, and the pull wire lumens 203 are symmetrically distributed in the tube wall along the axial direction. Also included are two other lumens 204 for guidewire or saline lumens. The cavity is wrapped with an outer tube layer 201, which is made of TPU, PeBax, nylon and other materials.

Please refer to accompanying drawing 8, in another embodiment, the catheter body is a hollow tubular structure with a guide wire lumen 213 in the middle, and four lumens 212 are evenly distributed in the tube wall of the catheter body, two of which are along the axial direction Symmetrically distributed lumens are used as puller lumens. The multi-lumen tube 211 can be prepared by an extrusion method, heat shrinking, and the like.

Please refer to accompanying drawing 9, in another embodiment, the catheter body is a hollow tubular structure with a guide wire lumen 223 in the middle, and eight lumens 222 are evenly distributed in the tube wall of the catheter body, two of which are along the axial direction Symmetrically distributed lumens are used as puller lumens. The multi-lumen tube 221 can be prepared by extrusion, heat shrinking and other methods.

Please refer to accompanying drawing 10, in another embodiment, described catheter main body is hollow tubular structure, and the center is

guide wire lumen

233, and 2 backguy lumens 232 are evenly distributed in the tube wall of catheter main body, additionally consists of two long The strip lumen 234 is used for routing other wires or as a saline lumen. The multi-lumen tube 231 can be prepared by extrusion, heat shrinking and other methods.

The above descriptions are only preferred embodiments of the present invention, which do not limit the protection scope of the present invention. For those skilled in the art, the present invention may have various modifications and changes. Within the spirit and principles of the present invention, changes, modifications, substitutions, integrations and parameter changes of these embodiments without departing from the principles and spirit of the present invention by conventional substitutions or capable of achieving the same function fall within the scope of the present invention. Into the protection scope of the present invention.

Claims

A two-way bendable spline basket ablation catheter is characterized in that it includes an adjustment handle, a catheter main body and a treatment head;

The adjusting handle includes a bending control knob, and the bending control knob is connected with 2 pull wires;

The catheter body is an elongated hollow tube extending axially, its proximal end is connected to the adjustment handle, and its distal end is connected to the treatment head, and the catheter body includes at least 2 axially symmetrically distributed backguy lumens;

The bending control knob bends the distal end of the catheter main body through at least two pull wires, so that the treatment head can be bent in two directions.
The bidirectionally bendable spline basket ablation catheter according to claim 1, wherein the treatment head comprises a spline basket having a plurality of splines, wherein each spline comprises at least one ring-shaped electrode.
The bidirectionally bendable spline basket ablation catheter according to claim 2, characterized in that, the annular electrodes on the splines are distributed at the distal end of the spline basket, accounting for 1/10-2/3 of the entire spline length scope.
The bidirectionally bendable spline basket ablation catheter according to claim 3, wherein each spline includes 1 to 5 ring electrodes.
The bidirectionally bendable spline basket ablation catheter according to claim 3, characterized in that, the ring electrode of each spline includes 1 short electrode located at the distal end of the spline and 1 to 4 electrodes at the middle and proximal parts long electrode.
The two-way bendable spline basket ablation catheter according to claim 1, wherein the main body of the catheter is a hollow tubular structure with a guide wire lumen in the middle, and the pull wire lumens are symmetrically distributed on the tube wall along the axial direction middle.
The bidirectionally bendable spline basket ablation catheter according to claim 6, wherein a plurality of lumens are distributed in the tube wall of the catheter body, and two of the lumens distributed symmetrically along the axial direction are used as puller lumens road.
The bidirectionally bendable spline basket ablation catheter according to claim 7, wherein the number of the plurality of lumens is preferably 2-8.
The bidirectionally bendable spline basket ablation catheter according to claim 7, wherein the shape of the lumen of the tube wall can be circular, elliptical, or elongated.
The bidirectionally bendable spline basket ablation catheter according to any one of claims 1-9, characterized in that the bending angle of the treatment head of the ablation catheter and the distal end of the catheter body can be adjusted within the range of 0-180° , so that the treatment head can quickly reach different angles of the pulmonary vein vestibule or other vein targets.