CN107661141A - Ablation catheter - Google Patents

Abstract

The present invention provides an ablation catheter, which includes a radially incompressible support body and at least one electrode arranged on the surface of the support body. The support body includes a distal cross section and a first cross section. The cross-section of the support corresponding to the distal end of the electrode closest to the distal end of the support among the at least one electrode is the first cross-section. The radial maximum length of any cross-section between the distal cross-section of the support body and the first cross-section is less than or equal to the radial maximum length of the first cross-section.

Description

Ablation Catheter

technical field

The invention relates to the field of medical devices, in particular to an ablation catheter.

Background technique

Hypertension is a common chronic disease. In its formation mechanism, the renin-angiotensin-aldosterone system (Renin Angiotensin Aldosterone System, RAAS) plays a key role as an important blood pressure regulation system. RAAS maintains the balance of water, electrolytes and blood pressure in the body through the regulation of the heart, blood vessels and kidneys. Studies have confirmed that RAAS causes hypertension through the following three pathways: (1) RAAS activation causes sodium retention; (2) RAAS activation can increase the activity of the sympathetic nervous system; (3) RAAS activation can directly constrict blood vessels. Among them, the renal artery sympathetic nerve plays a decisive role in inducing and maintaining systemic hypertension, and its overactivity makes it difficult to lower blood pressure in hypertensive patients.

Figure 1 shows the typical anatomy of the renal artery. The entrance of the main renal artery 2 is connected to the aorta 1, and the blood flow from the aorta 1 passes through the renal artery 2, the branch vessels 31, and the next-level branch vessels 311 and 312 separated by the branch vessels 31 (hereinafter referred to as secondary vessels) Branch vessels 311, 312) flow to the kidneys. Generally, the inner diameters of the secondary branch vessels 311 and 312 are smaller than the branch vessel 31 . Figure 2 shows the distribution of renal sympathetic nerves along the vessel wall of the renal artery. Renal sympathetic nerve fibers 4 (hereinafter referred to as nerve fibers 4 ) distributed in the renal artery wall are closely related to renal function. Viewed from the side of the blood vessel, the nerve fiber 4 extends along the blood vessel from the aorta 1 to the kidney 8 through the main renal artery 2 and branch vessels 31 of the renal artery (hereinafter referred to as branch vessels 31 ). Nerve fibers 4 are mainly distributed in the adventitia of the vessel wall they pass through.

Transcatheter renal artery sympathetic nerve ablation is aimed at the ablation of renal artery sympathetic nerves. Its typical mode of action is to deliver electrodes into the renal artery vessels of the patient's body through catheters, and apply energy to the renal artery vessels through these electrodes to achieve The purpose of ablation of the renal sympathetic nerve in the wall of the renal artery to lower the patient's blood pressure.

A nerve ablation system is disclosed in the prior art (as shown in FIG. 3 ). The system includes an energy generator 6 and an ablation catheter 5 . The energy generator 6 is used to emit energy, such as radio frequency energy. The ablation catheter 5 includes an elongated tubular body 57 , a balloon 76 disposed at the distal end of the tubular body 57 (that is, the end away from the operator), and an electrode 72 disposed on the balloon 76 . The proximal end of the tubular body 57 (that is, the end away from the operator) is connected to the energy generator 6 through a wire, and the energy emitted by the energy generator 6 can be transmitted to the electrode 72 . The balloon 76 is a relatively regular, nearly cylindrical columnar structure. The electrodes 72 can be fed into the blood vessel and deliver energy from within the blood vessel to the vessel wall, deactivating the nerve fibers 4 .

However, when there are irregularly shaped locations in the target vessel, such as at the entrance of the renal artery or at the stenosis of the renal artery, it is difficult for the electrode to completely fit the vessel wall, or the inner diameter of the target vessel is small and the balloon cannot be fully deployed in the vessel , the electrode will be difficult to fit the vessel wall due to the obstruction of the balloon, which will lead to poor ablation effect and low ablation efficiency.

Contents of the invention

Based on this, it is necessary to provide an ablation catheter whose electrodes have good wall-attachment performance, better ablation effect and higher ablation efficiency.

The present invention provides an ablation catheter, which includes a radially incompressible support body and at least one electrode arranged on the surface of the support body. The support body includes a distal cross section and a first cross section. The cross-section of the support corresponding to the distal end of the electrode closest to the distal end of the support among the at least one electrode is the first cross-section. The radial maximum length of any cross-section between the distal cross-section of the support body and the first cross-section is less than or equal to the radial maximum length of the first cross-section.

In one embodiment, grooves are provided on the side of the support body, and the grooves extend along the axial direction of the support body.

In one embodiment, the circumferential width of the groove along the side of the support gradually increases from the distal end to the proximal end, and the electrodes are erected on the groove.

In one of the embodiments, the circumferential width of the groove along the side of the support body is equal from the distal end to the proximal end, the electrodes are linear electrodes, and the linear electrodes are arranged on the side surfaces of the support body , and the linear electrode is parallel to the axial direction of the support.

In one of the embodiments, the support body further has a second cross section located between the first cross section and its proximal end cross section, and the electrode closest to the support body proximal end among the at least one electrode The cross section of the support body corresponding to the proximal end is the second cross section, and the maximum radial length of the second cross section is less than or equal to the maximum radial length of the third cross section.

In one of the embodiments, the maximum radial length of the first cross-section of the support body is less than or equal to 1.1 mm, and the maximum radial length of the second cross-section is greater than or equal to 2.5 mm and less than or equal to 3.5 mm, The distance between the first cross section and the second cross section is greater than or equal to 4 mm and less than or equal to 7 mm.

In one of the embodiments, the maximum radial length of the first cross-section of the support body is less than or equal to 0.9 mm, and the maximum radial length of the second cross-section is greater than or equal to 2 mm and less than or equal to 2.5 mm, The distance between the first cross section and the second cross section is greater than or equal to 3 millimeters and less than or equal to 6 millimeters.

In one of the embodiments, the maximum radial length of the first cross-section of the support body is less than or equal to 2.5 mm, and the maximum radial length of the second cross-section is greater than or equal to 5 mm and less than or equal to 8 mm, The distance between the first cross section and the second cross section is greater than or equal to 4 mm and less than or equal to 12 mm.

In one of the embodiments, the maximum radial length of the first cross-section of the support body is less than or equal to 1 mm, and the maximum radial length of the second cross-section is greater than or equal to 2.5 mm and less than or equal to 3.5 mm, The distance between the first cross section and the second cross section is greater than or equal to 4 mm and less than or equal to 7 mm.

In one of the embodiments, the support body includes a plurality of support subunits and at least one flexible connection part, two adjacent support subunits among the plurality of support subunits are connected through the flexible connection part, the The electrodes are ring-shaped electrodes, and the ring-shaped electrodes are sheathed on the peripheral surface of the supporting subunit.

Compared with the ablation catheter in the prior art, the support body of the electrode of the ablation catheter in this solution is radially incompressible, and the diameter of any cross-section between the distal end cross-section and the first cross-section of the support body is The maximum radial length is less than or equal to the maximum radial length of the first cross-section, so the electrodes arranged on the surface of the support will not be hindered by the part of the support that enters the blood vessel, making it difficult to adhere to the blood vessel wall. The electrode can obtain good wall-attachment performance, achieve better ablation effect, and improve ablation efficiency.

Description of drawings

Figure 1 is a schematic diagram of a typical anatomical structure of the renal artery;

Figure 2 is a schematic diagram of the distribution of renal sympathetic nerves along the wall of the renal artery;

FIG. 3 is a schematic structural diagram of an existing nerve ablation system;

Fig. 4 is a schematic structural diagram of the nerve ablation system provided by the first embodiment of the present invention;

Fig. 5 is a schematic structural diagram of the ablation catheter of the nerve ablation system in Fig. 4;

Fig. 6 is a schematic diagram after the ablation catheter in Fig. 5 enters the branch vessel of the renal artery;

Fig. 7 is a schematic structural diagram of the ablation assembly provided by the second embodiment of the present invention;

Fig. 8 is a schematic structural diagram of the ablation assembly provided by the third embodiment of the present invention;

Fig. 9 is a schematic structural view of the ablation catheter provided by the fourth embodiment of the present invention;

Fig. 10 is a schematic structural view of the ablation catheter provided by the fifth embodiment of the present invention;

Fig. 11 is a schematic diagram of the ablation catheter in Fig. 10 after being attached to the vessel wall;

Fig. 12 is a schematic structural view of the ablation catheter provided by the sixth embodiment of the present invention;

Fig. 13 is a schematic structural view of the ablation catheter provided by the seventh embodiment of the present invention;

Fig. 14 is a schematic side view of the support body of the ablation catheter in Fig. 13 .

Detailed ways

In order to make the above objects, features and advantages of the present invention more comprehensible, specific implementations of the present invention will be described in detail below in conjunction with the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, the present invention can be implemented in many other ways different from those described here, and those skilled in the art can make similar improvements without departing from the connotation of the present invention, so the present invention is not limited by the specific implementations disclosed below.

It should be noted that, in the field of intervention, the end closer to the operator is usually called the proximal end, and the end farther away from the operator is called the distal end. It should also be noted that, in this application, the radial maximum length of a cross-section refers to the distance between the two farthest points on the cross-section.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field of the invention. The terms used herein in the description of the present invention are for the purpose of describing specific embodiments only, and are not intended to limit the present invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Please refer to FIG. 4 , a nerve ablation system 100 provided by a first embodiment of the present invention includes an energy generator 10 and an ablation catheter 20 for ablation of a target blood vessel. The energy generator 10 is a common instrument used by those skilled in the art, and the present invention does not repeat the structure and principle of the energy generator 10 .

The ablation catheter 20 includes a hollow and elongated tubular body 21 and an ablation component 23 disposed at the distal end of the tubular body 21 . The proximal end of the tubular body 21 is connected to the energy generator 10 through a wire (not shown), so as to transmit the energy emitted by the energy generator 10 to the ablation assembly 23 . The ablation assembly 23 includes a support body 231 and at least one electrode 233 disposed on the support body 231 .

The support body 231 has an axial direction and a radial direction. The axial direction of the support body 231 is consistent with the axial direction of the tubular body 21 , and its radial direction is perpendicular to the axial direction. The section along the radial direction, that is, the section perpendicular to the axial direction is defined as the cross section, and the direction of rotation around the axial direction is defined as the circumferential direction.

Please also refer to FIG. 5 , the supporting body 231 is radially incompressible and has a distal cross section 234 , a proximal cross section 235 , a first cross section 236 and a second cross section 237 . The first cross section 236 and the second cross section 237 are located between the distal cross section 234 and the proximal cross section 235 , and the first cross section 236 is closer to the distal cross section 234 than the second cross section 237 . The distal ends of all the electrodes 233 may be located in the same cross-section, or in different cross-sections. When the distal ends of all electrodes 233 are located in the same cross section, this cross section is defined as the first cross section 236 . When the distal ends of all electrodes 233 are not located in the same cross section, define the cross section of the support body 231 corresponding to the distal end of the electrode closest to the distal end of the support body 231 among all electrodes 233 as the first cross section 236. Similarly, the proximal ends of all the electrodes 233 may be located in the same cross-section, or in different cross-sections. When the proximal ends of all the electrodes 233 are located in the same cross section, this cross section is defined as the second cross section 237 . When the proximal ends of all the electrodes 233 are not located in the same cross section, the cross section of the support body 231 corresponding to the proximal end of the electrode closest to the proximal end of the support body 231 among all the electrodes 233 is the second cross section 237 . That is, all electrodes 233 are located between the first cross section 236 and the second cross section 237, the surface of the support body 231 located between the first cross section 236 and the second cross section 237 is defined as an electrode area, and the far end of the electrode area The cross section is the first cross section 236 , and the proximal cross section of the electrode region is the second cross section 237 . The radial maximum length of any cross-section between the distal cross-section 234 and the first cross-section 236 is less than or equal to the radial maximum length of the first cross-section 236 . Because blood vessels have certain elasticity, when the outer diameter of the ablation assembly 23 at the first cross section 236 is smaller than or equal to the inner diameter of the blood flow inlet of the target blood vessel, the electrodes 233 of the ablation assembly 23 can enter the target blood vessel. That is to say, in actual use of the electrodes, it is necessary to select an ablation component 23 whose outer diameter of the ablation component 23 at the first cross section 236 is smaller than or equal to the inner diameter according to the inner diameter of the blood inlet of the target blood vessel.

When the radial maximum length of the distal cross-section is less than or equal to the radial maximum length of the first cross-section, the radial maximum length of the first cross-section is less than the radial maximum length of the second cross-section, and the diameter of the second cross-section When the maximum length is less than or equal to the radial maximum length of the proximal cross-section, the distal cross-section of the support body 231 can quickly pass through the irregularly shaped position in the blood vessel, while the proximal cross-section is difficult to penetrate due to its large size. By blocking the position with irregular shape in the blood vessel, the support body 231 can be effectively positioned at the position with irregular shape in the blood vessel, shortening the operation time and improving the efficiency of ablation. In this embodiment, the support body 231 includes a truncated cone (ie, a truncated cone); the distal cross-section 234, the proximal cross-section 235, the first cross-section 236 and the second cross-section 237 are all circular; the distal cross-section The radial maximum length, the radial maximum length of the proximal cross-section, the radial maximum length of the first cross-section, and the radial maximum length of the second cross-section are diameters of respective circles.

Preferably, configuration one is adopted: the radial maximum length of the first cross-section is less than or equal to 1.1 mm, the radial maximum length of the second cross-section is greater than or equal to 2.5 mm and less than or equal to 3.5 mm, the first cross-section 236 and the second cross-section The distance between the two cross-sections 237 is greater than or equal to 4 mm and less than or equal to 7 mm, and the ablation assembly 23 can be positioned at the entrance of the branch vessel 31 of most patients as shown in FIG. 1 . Specifically, in this embodiment, the radial maximum length of the distal cross-section is 1 mm, the radial maximum length of the proximal cross-section is 3 mm, the radial maximum length of the first cross-section is 1.1 mm, and the second cross-section The radial maximum length of the section is 2.8 mm, and the distance between the first cross section 236 and the second cross section 237 is 4.2 mm.

The electrode 233 is disposed on the side of the support body 231 and located between the first cross section 236 and the second cross section 237 . In this embodiment, the number of electrodes 233 is four, and each electrode 233 is a linear electrode; the four electrodes 233 on the support body 231 are center-symmetrically distributed with the axial direction of the support body 231 as the axis of symmetry. That is to say, the extension direction of each electrode 233 on the support body 231 from the distal end to the proximal end forms an acute angle with the axial direction of the support body 231 from the distal end to the proximal end. In this way, after the multiple electrodes 233 enter the target blood vessel, they can There is a larger contact area with the target vessel wall, which improves the ablation efficiency.

Please refer to FIG. 6 , the ablation assembly 23 of the ablation catheter 20 can enter the blood vessel through the puncture point on the patient's femoral artery, and be pushed into the aorta 1 along the pre-arranged delivery sheath 9 . The ablation assembly 23 is movable in the main renal artery 2 . The operator can select a branch vessel 31 with an inner diameter of about 2.5 mm as the target vessel. The distal cross-section 234 can enter into the branch vessel 31, while the proximal cross-section 237 cannot. When an appropriate push force is applied to the catheter body 21 along the axial direction of the ablation catheter 20, the ablation assembly 23 will be positioned at the blood flow inlet of the target blood vessel, and at least a part of the electrode 233 will be in contact with the wall of the target blood vessel. It's like using a tapered cork to stop the bottle. On this basis, since the electrode 233 is located between the first cross section and the second cross section, the energy emitted by the energy generator 10 can be delivered to the target tissue through the electrode 233 to ablate the target tissue. The ablation assembly 23 is arranged with a plurality of electrodes 233 along the circumferential direction, so that when the ablation assembly 23 is positioned at the entrance of the target blood vessel, multiple electrodes 233 in the circumferential direction can be in contact with the blood vessel wall at the same time, and can simultaneously treat the blood vessel wall. Ablation is performed at multiple positions in the circumferential direction.

It can be understood that, in some other embodiments, when other conditions remain unchanged, only the positions of the first cross-section 236 and the distal cross-section 234 coincide, that is, the radial maximum length of the first cross-section is equal to that of the distal end. When the radial maximum length of the end cross-section is reached, the purpose that the support body 231 of the present invention can be effectively positioned at the entrance of the target blood vessel can also be achieved. It can also be understood that, in some other embodiments, when other conditions remain unchanged, the positions of the second cross-section 237 and the proximal cross-section 235 coincide, that is, the radial maximum length of the second cross-section is the same as that of the proximal cross-section. When the radial maximum lengths of the end cross-sections are equal, the purpose that the support body 231 of the present invention can be effectively positioned at the entrance of the target blood vessel can also be achieved.

It can be understood that, in other embodiments, the distal end of the support body 231 can also be hemispherical. At this time, the distal cross section 234 is a tangent point on a plane tangent to the most distal end of the hemispherical shape, that is, That is to say, the radial maximum length of the distal cross-section approaches zero, which can also achieve the purpose that the support body 231 of the present invention can be effectively positioned at the entrance of the target blood vessel.

Please refer to FIG. 7, the ablation assembly 23a provided by the second embodiment of the present invention is substantially the same as the ablation assembly 23, the difference is that the ablation assembly 23a includes a radially incompressible support body 231a and six The linear electrode 233a. The definitions of the axial direction and the radial direction of the support body 231 a are the same as the definitions of the axial direction and the radial direction of the support body 231 , and will not be repeated here.

The support body 231a is radially incompressible and includes a truncated hexagonal pyramid, that is to say, the support body 231a includes a truncated cone structure, and the cross section of the truncated cone structure is hexagonal. Specifically, the support body 231 has a hexagonal distal cross section 234a, a hexagonal proximal cross section 235a, a hexagonal first cross section 236a and a hexagonal second cross section 237a . The distal cross section 234a is the distal cross section of the support body 231a. The proximal cross-section 235a is the proximal cross-section of the support body 231a. The first cross section 236a and the second cross section 237a are located between the distal cross section 234a and the proximal cross section 235a, and the first cross section 236a is closer to the distal cross section 234a than the second cross section 237a. The cross section of the support body 231a where the distal end of the electrode 233a closest to the distal end of the support body 231a among the at least one electrode 233a is located is the first cross section 236a. The cross section of the support body 231a where the proximal end of the electrode 233a closest to the proximal end of the support body 231a among the at least one electrode 233a is located is the second cross section 237a. The radial maximum length of any cross-section between the distal cross-section 234a and the first cross-section 236a is less than or equal to the radial maximum length of the first cross-section 236a, and the outer surface of the ablation assembly 23a at the first cross-section 236a The diameter is smaller than or equal to the inner diameter of the blood flow inlet of the target blood vessel. When the radial maximum length of the distal cross-section is less than or equal to the radial maximum length of the first cross-section, the radial maximum length of the first cross-section is less than the radial maximum length of the second cross-section and the radial maximum length of the second cross-section When the maximum length is less than or equal to the radial maximum length of the proximal cross-section, the distal cross-section of the support body 231a is smaller and the proximal cross-section is larger, the support body 231a can be effectively positioned at the entrance of the target blood vessel, and the nerve The efficiency of modulation shortens the operation time.

Preferably, configuration two is adopted: the maximum radial length of the first cross-section is less than or equal to 0.9 millimeters, the maximum radial length of the second cross-section is greater than or equal to 2 millimeters and less than or 2.5 millimeters, the first cross-section 236a and The distance between the second cross-sections 237a is greater than or equal to 3mm and less than or equal to 6mm, and the ablation assembly 23a can be positioned at the blood flow inlet of the secondary branch vessels 311 of most patients as shown in FIG. 1 . Specifically, in this embodiment, the maximum radial length of the first cross-section is 0.8 mm, the maximum radial length of the second cross-section is 2.3 mm, and the distance between the first cross-section 236a and the second cross-section 237a is 4 mm.

The six linear electrodes 233a are all located in the electrode area, that is, between the first cross section 236a and the second cross section 237a, and one linear electrode 233a is located on one edge of the support 231a. The electrode 233a arranged on the edge of the support body 231a can exert greater pressure on the blood vessel wall, so that the blood vessel wall has a large local deformation, so that the electrode 233a can sink into the blood vessel wall, and the electrode 233a sunk into the blood vessel wall can Modulation of nerves distributed further from the vessel wall within the vessel wall.

It can be understood that, in other embodiments, the support body 231a may also include other truncated pyramids such as truncated pentagonal pyramids, truncated quadrangular pyramids, or truncated triangular pyramids. It can also be understood that the edges of the support body 231a can also be curved.

Referring to FIG. 8, the ablation assembly 23b provided by the third embodiment of the present invention is substantially the same as the ablation assembly 23, except that the radially incompressible support body 231b of the ablation assembly 23b includes a truncated elliptical cone, that is to say , the support body 231b includes a frusto-conical structure, and the cross-section of the frusto-conical structure is an ellipse with a non-axisymmetric shape. The plurality of electrodes 233b of the ablation assembly 23b are distributed near both ends of the major axis of the ellipse, so that the electrodes 233b can contact the blood vessel wall. In addition, just because the plurality of electrodes 233b are distributed near the two ends of the long axis of the ellipse, when the support body 231 with an elliptical cross section is positioned at the blood flow inlet of the target blood vessel, the positions near the two ends of the long axis on its cross section are the same as The blood vessel wall is in contact with the blood vessel wall, but the positions close to both ends of the short axis on the cross section are not in contact with the blood vessel wall, so that the blood can flow through the gap between the support body 231 and the blood vessel wall, and the blood flowing through the gap continuously takes away the heat of the electrode 233b, which is beneficial to The electrode 233b can lower the temperature, so as to avoid excessive damage to adjacent tissues caused by the electrode 233b due to excessive temperature.

Please refer to FIG. 9 , the ablation catheter 20c provided by the fourth embodiment of the present invention is substantially the same as the ablation catheter 20 , which includes a hollow elongated tubular body 21c and an ablation component 23c disposed at the distal end of the tubular body 21c.

The tubular main body 21c is substantially the same as the tubular main body 21 and will not be repeated here.

The ablation assembly 23c includes a radially incompressible support body 231c and a plurality of electrodes 233c disposed on the support body 231 .

The support body 231c is substantially identical to the support body 231, having a distal cross-section 234c, a proximal cross-section 235c, a first cross-section 236c and a second cross-section 237c. The definitions of the distal cross section 234c, the proximal cross section 235c, the first cross section 236c and the second cross section 237c are the same as those of the distal cross section 234, the proximal cross section 235, the first cross section 236 and the first embodiment. The definition of the second cross-section 237 is the same and will not be repeated here. The radial maximum length of the distal cross-section 234c is less than or equal to the radial maximum length of the first cross-section 236c, the radial maximum length of the first cross-section 236c is less than the radial maximum length of the second cross-section 237c, and the second cross-section The radial maximum length of 237c is less than or equal to the radial maximum length of proximal cross-section 235c. The radial maximum length of any cross-section between the distal cross-section 234c and the first cross-section 236c is less than or equal to the radial maximum length of the first cross-section 236c, and the outer surface of the ablation assembly 23c at the first cross-section 236c The diameter is smaller than the inner diameter of the blood flow inlet of the target blood vessel. Preferably, configuration three is adopted: the radial maximum length of the first cross-section is less than or equal to 2.5 millimeters, the radial maximum length of the second cross-section is greater than or equal to 5 millimeters and less than or equal to 8 millimeters, the first cross-section 236c and the second cross-section The distance between the two cross-sections 237c is greater than or equal to 4 mm and less than or equal to 12 mm, and the ablation assembly 23d can be positioned at the blood flow inlet of the main renal artery 2 of most patients as shown in FIG. 1 . Specifically, in this embodiment, the maximum radial length of the first cross section is 2 mm, the maximum radial length of the second cross section is 6 mm, and the distance between the first cross section 236c and the second cross section 237c is 8mm.

The difference between the support body 231c and the support body 231 is that the side surface of the support body 231c is provided with a plurality of grooves 238c extending along the axial direction of the support body 231c, and each groove 238c has a circumferential direction on the side surface of the support body 231d. The length gradually increases from the far end to the proximal end of the support body 238c, so that a protrusion 239c is formed between two adjacent grooves 238c; The guide wire lumen 232c, the guide wire lumen 232c communicates with the lumen of the tubular body 21c, so that the distal end of the guide wire can enter the guide wire lumen 231c of the support body 231c through the lumen of the tubular body 21c. The diameter of the guide wire cavity 232c is greater than 0.4 mm and less than 1.5 mm, so that the guide wire can enter the target blood vessel more smoothly. In this embodiment, the diameter of the guide wire lumen 232c is 1 mm. It can be understood that, in other embodiments, the guide wire cavity 231c of the support body 231c can also be omitted according to the actual situation.

The plurality of electrodes 233c are located between the electrode region, that is, between the first cross section 236c and the second cross section 237c, and the plurality of electrodes 233c are different from the plurality of electrodes 233 . Specifically, each electrode 233c is arc-shaped, and each electrode 233c is erected on a groove 238c, that is, two ends of each electrode 233c are respectively disposed on two adjacent protrusions 239c. In this way, when the support body 231c is positioned at the blood flow inlet of the target blood vessel, the blood flow can flow to the distal end of the support body 231c through the groove 238c. The blood flowing through the groove 238c continuously takes away the heat of the electrode 233c, thereby cooling the electrode 233c and preventing the electrode 233c from causing excessive damage to adjacent tissues due to excessive temperature.

When the doctor performs the operation, he can first send the guide wire into the target blood vessel to establish a track, and then deliver the ablation assembly 23c on the ablation catheter 20c to the target blood vessel along the guide wire track established by the guide wire The blood flow entrance.

Please refer to FIG. 10 , the ablation catheter 20d provided by the fifth embodiment of the present invention is substantially the same as the ablation catheter 20c, which includes a hollow elongated tubular body 21d and an ablation component 23d disposed at the distal end of the tubular body 21d. The tubular main body 21d is substantially the same as the tubular main body 21d, and will not be repeated here.

The ablation component 23d includes a radially incompressible support body 231d, electrodes 23d1, 23d2, 23d3 and 23d4 disposed on the support body 231d.

The support body 231d is substantially the same as the support body 231c, having a distal cross-section 234d, a proximal cross-section 235d, a first cross-section 236d, and a second cross-section 237d. The definitions of the distal cross section 234d, the proximal cross section 235d, the first cross section 236d and the second cross section 237d are the same as the distal cross section 234, the proximal cross section 235, the first cross section 236 and the first embodiment. The definition of the second cross-section 237 is the same and will not be repeated here. The radial maximum length of the distal cross-section 234d is less than or equal to the radial maximum length of the first cross-section 236d, the radial maximum length of the first cross-section 236d is less than the radial maximum length of the second cross-section 237d, and the second cross-section The radial maximum length of 237d is less than or equal to the radial maximum length of proximal cross-section 235d. A side surface of the support body 231d is provided with a plurality of grooves 238d extending along the axial direction of the support body 231d.

The support body 231d is a hollow structure, which has a guide wire lumen 232d axially penetrating the support body 231d, and the guide wire lumen 232d communicates with the lumen of the tubular main body 21d, so that the distal end of the guide wire can pass through the tube of the tubular main body 21d. The lumen enters the guidewire lumen 232d of the support body 231d. The diameter of the guide wire lumen 232d is greater than 0.4 mm and less than 1.5 mm, so that the guide wire can enter the target blood vessel more smoothly. In this embodiment, the diameter of the guide wire lumen 232d is 0.8 mm. It can be understood that, in other embodiments, the guide wire cavity 231d of the support body 231d can also be omitted according to the actual situation.

The difference between the support body 231d and the support body 231c is that the circumferential length of each groove 238d on the side of the support body 231d is equal from the distal end to the proximal end of the support body 238d, so that two adjacent grooves 238d A sheet-like protrusion 239d is formed therebetween.

Each of the electrode 23d1, the electrode 23d2, the electrode 23d3, and the electrode 23d4 is located between the first cross section 236d and the second cross section 237d. Each of the electrode 23d1, the electrode 23d2, the electrode 23d3, and the electrode 23d4 is linear. Each electrode in the electrode 23d1, the electrode 23d2, the electrode 23d3 and the electrode 23d4 is arranged on the side of the sheet-shaped protrusion 239d away from the axis of the support body 231d, and the length direction of each electrode is parallel to the side of the support body 231d. axis direction. In this way, when the support body 231d is positioned at the blood flow inlet of the target blood vessel, the blood flow can flow to the distal end of the support body 231d through the groove 238d. The blood flowing through the groove 238d continuously takes away the heat of the electrodes around the groove 238d, cooling the electrodes around the groove 238d, and preventing the electrodes around the groove 238d from causing excessive damage to adjacent tissues due to excessive temperature .

In addition, in this embodiment, the length direction of each of the electrodes 23d1 , 23d2 , 23d3 and 23d4 is parallel to the axial direction of the support 231d. When the support body 231d is in contact with the vessel wall at the entrance of the branch vessel 31, the cross section of the branch vessel 31 and the cross section of the ablation assembly 23d at the contact position are shown in FIG. 11 . In the figure, the part with thinner cross-hatching represents the cross-section of the branch blood vessel 31, the part with denser cross-hatching represents the cross-section of the ablation assembly 23d, and the nerve fibers 4 are distributed in the vessel wall. The vessel wall on the entire cross section can be regarded as a structure including vessel wall tissue 314, vessel wall tissue 315, vessel wall tissue 316 and vessel wall tissue 317, and vessel wall tissue 314, vessel wall tissue 315, vessel wall tissue 316 and vessel wall tissue Each vessel wall tissue in wall tissue 317 is placed between two adjacent electrodes. In this case, the energy emitted from the energy generator (not shown) can establish a bipolar electric field between two adjacent electrodes. The blood vessel wall tissue located between two adjacent electrodes is affected by the bipolar electric field, and the temperature will rise. When the temperature rises to a certain level, the cells in the tissue, including the nerve fiber 4 cells, will be damaged, so that The activity of the renal sympathetic nerves is reduced. Compared with the technical solution of monopolar electric field, the technical solution of bipolar electric field has the advantages that: on the one hand, the modulated blood vessel wall tissue is between two adjacent electrodes, and the modulation range is clearer; on the other hand, In the technical scheme of unipolar electric field, the modulated blood vessel wall tissue is the local tissue in contact with the electrode. In order to achieve a sufficient modulation range, the size of the electrode is often made relatively large. In the technical scheme of bipolar electric field, the modulated The blood vessel wall tissue is distributed between two adjacent electrodes, so the size of the electrode can be designed to be smaller, and the heat generated by the electrode itself is also small, which reduces the damage to the intima of the blood vessel in direct contact with the electrode. In addition, in actual operation, the first bipolar electric field can be established between the two electrodes 23d1 and 53d4 at both ends of the blood vessel wall tissue 314 in a certain period of time according to actual needs, and the two electrodes 23d1 and 53d4 in the circumferential direction of the blood vessel wall tissue 316 can establish a first bipolar electric field. A second bipolar electric field is established between the two electrodes 53d2 and 53d3 at the end, and the potential difference between the electrode 23d1 and the electrode 23d2 is zero, and the potential difference between the electrode 23d3 and the electrode 23d4 is zero. The blood vessel wall tissue 314 and the blood vessel wall tissue 316 in the bipolar electric field are modulated, but the blood vessel wall tissue 315 and the blood vessel wall tissue 317 are not modulated; in another time period, the blood vessel wall tissue 315 can also A third bipolar electric field is established between the two electrodes 23d1 and 23d2 at the end of the blood vessel wall tissue 317, and a fourth bipolar electric field is established between the two electrodes 23d3 and 23d4 at both ends of the blood vessel wall tissue 317, and the electrodes 23d1 and 23d4 The potential difference between them is zero, and the potential difference between the electrode 23d2 and the electrode 23d3 is zero, then only the blood vessel wall tissue 315 and the blood vessel wall tissue 317 in the third and fourth bipolar electric fields are modulated, and the blood vessel wall tissue 314 and vessel wall tissue 314 are not modulated. It can also be understood that the number of sheet-shaped protrusions 239c can also be five, seven or more, and the number of corresponding electrodes can also be five, seven or more. According to actual needs, Different combination relationships can be formed between multiple electrodes to form bipolar electric fields at different positions, so that the blood vessel wall tissue in the entire circumferential direction of the target blood vessel can be modulated or a certain proportion of the blood vessel wall tissue in the entire circumferential direction of the target blood vessel can be modulated. to modulate.

Please refer to FIG. 12 , the sixth embodiment of the present invention provides an ablation catheter 20e including a catheter body 21e and an ablation assembly 23e. The ablation assembly 23e includes a radially incompressible support body 231 . The support body 231 includes a connected first support subunit 231e in the shape of a truncated cone, a second support subunit 232e in the shape of a truncated cone, and a third support subunit 233e in the shape of a truncated cone. The radial maximum length of the proximal end surface of each support subunit 231e, the second support subunit 232e and the third support subunit 233e is smaller than the radial maximum length of the distal end surface of the same support subunit. length. The second supporting subunit 232e is located between the first supporting subunit 231e and the third supporting subunit 233e, and the first supporting subunit 231e is closer to the distal end of the ablation component 23e than the third supporting subunit 233e. The first support subunit 231e is connected to the second support subunit 232e through a flexible connection part 234e; the second support subunit 232e is also connected to the third support subunit 233e through a flexible connection part 234e. In this way, the ablation assembly 23a comprising a plurality of support subunits has the feature of being axially bendable, which is beneficial for passing some twisted blood vessel positions. The flexible connecting part 234e is a flexible solid tube or a hollow tube. Preferably, in this embodiment, the flexible connecting part 234e is a block polyetheramide solid tube with a braided mesh.

It can be understood that, in other embodiments, the flexible connecting part 234e may also be a block polyetheramide hollow tube with a braided mesh. It can also be understood that, in other embodiments, the number of support bodies in the ablation assembly 23e may also be two, four or more. It can also be understood that, in other embodiments, the support body in the ablation assembly 23e may be a hollow structure or a solid structure. It can also be understood that in other embodiments, the shape of the first support subunit 231e, the shape of the second support subunit 232e and the shape of the third support subunit 233e can be the same or different, for example, when multiple supports When the shapes of the subunits are the same, the shape of the first support subunit 231e, the shape of the second support subunit 232e and the shape of the third support subunit 233e can also be truncated prisms, truncated cones, truncated elliptical cones, Shapes such as truncated square pyramid, truncated pentagonal pyramid or truncated hexagonal pyramid; also for example, when the shapes of multiple supporting subunits are different, the first supporting subunit 231e, the second supporting subunit 232e and the third supporting subunit In 233e, one support unit is in the shape of a circular frustum, and the other two support units are in the shape of a truncated prism, a truncated cone, a truncated elliptical cone, a truncated square pyramid, a truncated pentagonal pyramid, or a truncated hexagonal pyramid. Set according to actual needs.

There is also a closed ring electrode 235e on the peripheral surface of the first support subunit 231e; a closed ring electrode 236e is also provided on the peripheral surface of the second support subunit 232e; A ring electrode 237e having an opening is provided.

It should be noted that, in this embodiment, the distal cross section of the first support subunit 231e is the distal cross section of the support body 231; the proximal cross section of the third support unit 233e is the proximal end of the support body 231 Cross section; the cross section of the first support unit 231e at the far end of the electrode 235e is the first cross section of the support body 231; the cross section of the third support subunit 233e at the proximal end of the electrode 237e is the support body 231 the second cross section of . Preferably, configuration four is adopted: the maximum radial length of the first cross-section is less than or equal to 1 mm, the maximum radial length of the second cross-section is greater than or equal to 2.5 mm and less than or equal to 3.5 mm, the first cross-section and the second The distance between the cross-sections is greater than or equal to 4 mm and less than or equal to 7 mm, and the ablation assembly 23e can be positioned at the entrance of a blood vessel with an inner diameter greater than 1 mm and less than 3 mm. In this embodiment, the maximum radial length of the first cross section is 0.9 mm, the maximum radial length of the second cross section is 2.8 mm, and the distance between the first cross section and the second cross section is 5 mm.

It can be understood that, according to actual needs, the ring electrodes in this embodiment can also be replaced by electrodes of other shapes such as linear electrodes and arc electrodes. The cross-section closest to the distal end of the third support subunit 233e is the first cross-section of the support body 231, and the cross-section closest to the proximal end of the electrode on the third support subunit 233e is the second cross-section of the support body 231.

Preferably, in this embodiment, a temperature sensitive element 238e is provided on the peripheral surface of the third supporting subunit 233e near the opening of the ring electrode 237e to detect the temperature at the position of the ring electrode 237e. It can be understood that, in other embodiments, the ring electrode 235e or the ring electrode 236e may also be a ring electrode with an opening. It can also be understood that, in other embodiments, the second support subunit 232e and/or the first support subunit 231e may also be provided with a temperature sensitive element 238e to detect the temperature at the position of the corresponding electrode.

The ablation assembly 23e further includes a guide segment 239e connected to the distal end of the first supporting subunit 231e, so as to better guide the ablation assembly 23e into the target blood vessel. Preferably, in this embodiment, the guide section 239e is approximately J-shaped, and is integrally formed with the first supporting subunit 231e.

When the operator applies a push force along the axial direction of the ablation assembly 23e, the guide segment 239e can enter into the target blood vessel. It can be understood that if the inner diameter of the blood flow inlet of the target blood vessel is slightly smaller than the outer diameter of the ablation assembly 23e at the distal end of the electrode 235e on the first support subunit 231e, the target blood vessel can be slightly ablated after the operator applies an appropriate pushing force. When the electrode 235e is expanded, the electrode 235e can be in contact with the blood vessel wall; if the inner diameter of the blood flow inlet of the target vessel is greater than the maximum outer diameter of the ablation assembly 23e where the electrode 235e is located, and smaller than the outer diameter of the ablation assembly 23e at the distal end of the electrode 236e, then After the operator applies an appropriate pushing force, the first supporting subunit 231e enters into the target blood vessel, while the second supporting subunit 232e can properly expand the target blood vessel, and the electrode 236e can contact the blood vessel wall; if the blood flow inlet of the target blood vessel The inner diameter of the electrode 236e is greater than the maximum outer diameter of the ablation assembly 23e where the electrode 236e is located, and is smaller than the outer diameter of the ablation assembly 23e at the proximal end of the electrode 237e, then the operator applies an appropriate pushing force, and both the electrode 235e and the electrode 236e enter the blood vessel , and the electrode 237e can be in contact with the target blood vessel wall; if the inner diameter of the blood flow inlet of the target blood vessel wall is greater than the diameter of the proximal end of the third support subunit 233e, the ablation assembly 23e can completely enter the blood vessel, and the operator can continue to apply The pushing force moves the ablation component 23e toward the branch vessels of the blood vessel, and finds a vessel with an appropriate inner diameter among the branch vessels as the target vessel.

Please refer to FIG. 13 and FIG. 14 , the ablation catheter 20f provided by the seventh embodiment of the present invention is substantially the same as the ablation catheter 20e, and includes a catheter main body 21f and an ablation component 23f. The ablation component 23f includes a radially incompressible support body 231 and three electrodes (ie, a ring electrode 237f , a ring electrode 238f and a ring electrode 239f ) disposed on the support body 231 . The support body 231 includes a first support subunit 231f, a second support subunit 232f, and a third support subunit 233f

The radial maximum length of the proximal end surface of each support subunit 231f, the second support subunit 232f and the third support subunit 233f is smaller than the radial maximum length of the distal end surface of the same support subunit. length. The second supporting subunit 232f is located between the first supporting subunit 231f and the third supporting subunit 233f, and the first supporting subunit 231f is closer to the distal end of the ablation component 23f than the third supporting subunit 233f. The first support subunit 231f is connected to the second support subunit 232f through a flexible connection part 234f; the second support subunit 232f is also connected to the third support subunit 233f through a flexible connection part 234f. In this way, the ablation assembly 23f comprising a plurality of supports has the feature of being axially bendable, which is beneficial for passing through some twisted blood vessel positions. The flexible connecting part 234f is a flexible solid tube or a hollow tube. Preferably, in this embodiment, the flexible connecting part 234f is a block polyetheramide hollow tube with a braided mesh. It can be understood that, in other embodiments, the flexible connecting part 234f may also be a block polyetheramide solid tube with braided mesh. It can also be understood that, in other embodiments, the number of support bodies in the ablation assembly 23f may also be two, four or more. It should be noted that the definitions of the distal cross-section, proximal cross-section, first cross-section, and second cross-section of the support body 231 of the ablation assembly 23f are similar to the definitions of the distal cross-section and proximal cross-section of the support body 231 of the ablation assembly 23e. The definitions of the cross-section, the first cross-section and the second cross-section are the same and will not be repeated here.

The difference between the ablation assembly 23f and the ablation assembly 23e is that: the proximal end of the first support subunit 231f is recessed toward the distal end of the first support subunit 231f to form a first groove 235f, and the second support subunit 232f The distal end of the second support subunit 232f is received in the first groove 235f; the proximal end of the second support subunit 232f is recessed toward the distal end of the second support subunit 232f to form a second groove 236f, and the third support subunit 233f The distal end is accommodated in the second groove 236f. The advantage of such a nested structure is that it not only improves the flexibility of the ablation component 23f, but also does not need to increase the length of the ablation component 23f, directly making the structure of the ablation catheter with the ablation component 23f more compact.

It can be understood that the radial maximum length of the first cross-section, the radial maximum length of the second cross-section, and the distance between the first cross-section and the second cross-section It can be set according to actual needs, that is, the radial maximum length of the first cross-section, the radial maximum length of the second cross-section, and the first cross-section and the second cross-section The distance between them can be set according to configuration 1, configuration 2, configuration 3 or configuration 4 according to actual needs.

It should be noted that, according to actual needs, the materials constituting the electrodes can be metals with high density, such as platinum, gold, tantalum or other metals or alloys that are difficult for X-rays to penetrate. In this way, the doctor can see the images of the electrodes through X-ray equipment such as DSA equipment (digital subtraction angiography equipment), which is convenient for operation. It should also be noted that, according to actual needs, the support body of the ablation component can also contain materials that are difficult to transmit X-rays. Preferably, the support body of the ablation component can be made of block polyetheramide resin containing a certain proportion of barium sulfate (trade name Pebax) to facilitate surgical manipulation. It should also be noted that in some embodiments, the electrode and the support body can also be an integral structure made of the same material. Such an integral structure not only has the characteristics of the support body supporting the electrode, but also has the function of being an electrode. For example, the support itself is made of platinum-iridium alloy, and is connected to the energy generator through wires arranged in the main body of the catheter, so that the support also functions as an electrode. It should also be noted that, in order to pass through some curved paths, in some embodiments, the support body can be set as a structure with certain axial flexibility, for example, a support body made of a silicone material with a Shore hardness of 30A to 70A It has a certain axial flexibility. It should also be noted that, in some embodiments, if the ablation component does not have obvious flexibility, its axial length needs to be limited so as to pass through some curved paths, for example, the axial length of the ablation component that does not have obvious flexibility can be reduced. The length is less than 7 mm, preferably less than 5.5 mm.

It should be noted that the distal ends of the ablation components in the first to fifth embodiments can be provided with a guide section according to actual needs, and if the length of the guide section is too long, it will be hindered in the branch vessels of the target vessel. If the length of the guide section is too short, the guiding effect will be poor. Therefore, in order to enable the operator to position the ablation component to the target more smoothly At the blood flow inlet of the blood vessel, the length of the guide section is in the range of 30 mm to 75 mm. Preferably, the length of the guide segment 239e is in the range of 40 mm to 65 mm, such as 55 mm.

It can be understood that the support bodies in the first to third embodiments and the sixth to seventh embodiments may also have a guide wire lumen like the support body in the fourth embodiment. It can also be understood that the support body in the fourth and fifth embodiments may also not have a guide wire lumen like the support body in the first embodiment.

It can also be understood that the ablation catheter in the above embodiment can also have a perfusion chamber for perfusion liquid (such as physiological saline or contrast agent); the inlet of the perfusion chamber can be arranged at the proximal end of the ablation catheter; the outlet of the perfusion chamber can be There can be one, or there can be multiple, which can be set according to actual needs. When the perfusion liquid is physiological saline, the perfusion liquid can assist in taking away excess heat generated by the electrodes to cool the electrodes. At this time, the outlet of the perfusion chamber can be arranged on the side of the support close to the electrodes to better cool the electrodes. When the perfusion fluid is a contrast agent, the outlet of the perfusion chamber can also be arranged on the ablation catheter near the ablation assembly, preferably, the outlet of the perfusion chamber can be arranged on the ablation catheter at a distance of 513 mm to 10 mm from the proximal end of the ablation assembly position, so that less contrast agent is used to show where the ablation component is located in the blood vessel.

It can be understood that the surface of the ablation catheter in the above embodiments may be provided with a hydrophilic coating to reduce friction between the ablation catheter and the vessel wall. In order to make the hydrophilic coating have a better effect, the hydrophilic coating is at least provided on a section of the main body of the ablation catheter close to the ablation component. Preferably, the length from the proximal end of the hydrophilic coating to the proximal end of the ablation assembly along the axial direction of the catheter body is greater than or equal to 15 mm.

The above-mentioned embodiments only express several implementation modes of the present invention, and the description thereof is relatively specific and detailed, but should not be construed as limiting the patent scope of the present invention. It should be pointed out that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be based on the appended claims.

Claims (10)

1. An ablation catheter, comprising a radially incompressible support body and at least one electrode disposed on the surface of the support body, the support body comprising a distal cross section and a first cross section, and the at least one electrode center distance The cross-section of the support body corresponding to the distal end of the nearest electrode at the distal end of the support body is the first cross-section, and any cross-section between the distal end cross-section of the support body and the first cross-section The radial maximum length is less than or equal to the radial maximum length of the first cross-section. 2 . The ablation catheter according to claim 1 , wherein grooves are provided on the side of the support body, and the grooves extend along the axial direction of the support body. 3 . 3. The ablation catheter according to claim 2, wherein the width of the groove in the circumferential direction along the side of the support gradually increases from the distal end to the proximal end, and the electrodes are mounted on the groove superior. 4. The ablation catheter according to claim 2, characterized in that, the circumferential width of the groove along the side of the support body is equal from the distal end to the proximal end, the electrodes are linear electrodes, and the linear electrodes It is arranged on the side of the supporting body, and the linear electrode is parallel to the axial direction of the supporting body. 5. The ablation catheter according to claim 1, wherein the support body further has a second cross-section located between the first cross-section and its proximal cross-section, the at least one electrode is at a distance from the The cross-section of the support corresponding to the proximal end of the nearest electrode at the proximal end of the support is the second cross-section, and the maximum radial length of the second cross-section is less than or equal to the diameter of the third cross-section. to the maximum length. 6. The ablation catheter according to claim 5, wherein the radial maximum length of the first cross-section of the support body is less than or equal to 1.1 mm, and the radial maximum length of the second cross-section is greater than or equal to 2.5 mm to less than or equal to 3.5 mm, and the distance between the first cross-section and the second cross-section is greater than or equal to 4 mm and less than or equal to 7 mm. 7. The ablation catheter according to claim 5, wherein the radial maximum length of the first cross-section of the support body is less than or equal to 0.9 mm, and the radial maximum length of the second cross-section is greater than or equal to 2 mm and less than or equal to 2.5 mm, and the distance between the first cross section and the second cross section is greater than or equal to 3 mm and less than or equal to 6 mm. 8. The ablation catheter according to claim 5, wherein the radial maximum length of the first cross-section of the support body is less than or equal to 2.5 mm, and the radial maximum length of the second cross-section is greater than or equal to 5 mm and less than or equal to 8 mm, and the distance between the first cross section and the second cross section is greater than or equal to 4 mm and less than or equal to 12 mm. 9. The ablation catheter according to claim 5, wherein the radial maximum length of the first cross-section of the support body is less than or equal to 1 mm, and the radial maximum length of the second cross-section is greater than or equal to 2.5 mm to less than or equal to 3.5 mm, and the distance between the first cross-section and the second cross-section is greater than or equal to 4 mm and less than or equal to 7 mm. 10. The ablation catheter according to claim 1, wherein the support body comprises a plurality of support subunits and at least one flexible connecting part, and two adjacent support subunits among the plurality of support subunits pass through The flexible connecting parts are connected together, the electrodes are ring-shaped electrodes, and the ring-shaped electrodes are sheathed on the peripheral surface of the supporting subunit.