Pulse potential ablation catheter

Abstract

The invention provides a pulse potential ablation catheter which is controlled by a remote host and provides pulse energy, the pulse potential ablation catheter comprises a flexible catheter, an elastic push rod and a pulse ablation part, and the elastic push rod is an inner core of the flexible catheter and is controlled to be pushed and pulled by a far-end operating handle; the hemispherical ring array ultrasonic probe and a fixing ring with a built-in magnetic positioning sensor are fixed to the front end and the rear end, extending out of the flexible catheter, of the elastic push rod respectively, and the pulse ablation parts are annularly distributed on the extending part of the elastic push rod in a spherical shape and fixed to the hemispherical ring array ultrasonic probe and the fixing ring respectively in a bundling mode. And the top end of the elastic push rod is wrapped in the hemispherical structure by the hemispherical ring array ultrasonic probe. The method has the advantages that the adaptability is high, the treatment effect and safety are improved, damage to surrounding tissue is reduced, imaging is more accurate, the comfort and convenience of surgical operation are improved, and excessive ablation and incomplete ablation are avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a pulse potential ablation catheter for treating pulmonary hypertension. Background Art

[0002] In the field of electrophysiological therapy, pulse ablation catheters deliver ablation electrodes to the lesion area through blood vessels, and use ablation electrodes to apply an ablation electric field to the lesion area to form pores on the cell membrane of target cells, thereby destroying cell stability and causing target cells to die. Compared with traditional radiofrequency ablation and cryoablation techniques, pulse ablation has shown many advantages, including selective destruction of tissues, non-thermal ablation mechanism, rapid energy release, good injury effect and shortened operation time, but existing pulse ablation still has defects to varying degrees in the electrode ablation process.

[0003] Although the existing ring electrode has a simple structure, it is difficult to expand and adjust, and requires high skills from the operator, and may not achieve the ideal ablation effect; although the strip ball cage electrode is easy to fold, adjacent electrodes may accidentally touch during operation, causing sparks; although the mesh ball cage electrode is stable, when released from the delivery catheter, the rapid or excessive expansion of the spherical electrode may cause damage to human tissue, and it may also be difficult to retract due to excessive or too fast traction force in the inner tube.

[0004] Since different lesion areas have different shapes, the ablation components in the prior art are difficult to form effective contact with various lesion areas, resulting in poor contact, insufficient electric field, poor ablation effect, etc. The operator needs to constantly adjust the contact angle to find a better contact position, which makes the operation difficult, the operation time long, and the surgical risk increased.

[0005] The existing pulse ablation combined with visualized surgical operation, the visualization equipment and level are not precise and advanced enough, the positioning of the lesion area during surgery is not accurate enough, and the image resolution of the lesion area is also poor, which not only affects the comfort of the surgical operation and prolongs the operation time, but also the surgical treatment effect is poor. Summary of the invention

[0006] The purpose of the present invention is to provide a pulse potential ablation catheter with strong adaptability, improved treatment effect and safety, reduced damage to surrounding tissues, more accurate imaging, improved comfort and convenience of surgical operations, and avoidance of excessive ablation and incomplete ablation.

[0007] In order to achieve the above object, the present invention is implemented by the following technical solutions: A pulse potential ablation catheter is controlled by a remote host and provides pulse energy, comprising a flexible catheter, an elastic push rod, and a pulse ablation part. The elastic push rod is the inner core of the flexible catheter and is controlled to be pushed and pulled by a remote operating handle. The front and rear ends of the part of the elastic push rod extending out of the flexible catheter are respectively fixed with a hemispherical ring array ultrasound probe and a fixing ring with a built-in magnetic positioning sensor. The pulse ablation part is spherically distributed on the extended part of the elastic push rod and is respectively bundled and fixed on the hemispherical ring array ultrasound probe and the fixing ring. The hemispherical ring array ultrasound probe wraps the top end of the elastic push rod in a hemispherical structure.

[0008] Furthermore, the pulse ablation part is formed into a spherical shape by 32 independent coated guide wires woven in an equidistant manner in the vertical and horizontal directions, each bundle of coated guide wires is provided with an independent positive and negative electrode column, and the 32 electrode columns are evenly distributed.

[0009] Furthermore, the pulse ablation part is formed into a spherical shape by evenly distributing 8 arc-shaped coated spring pieces, and an anode piece and a cathode piece are respectively arranged on a single coated spring piece.

[0010] Furthermore, shaping wires are provided between adjacent plated spring sheets to ensure the pulse ablation portion maintains spherical stability.

[0011] Furthermore, the hemispherical annular array ultrasonic probe is composed of a plurality of ultrasonic array elements uniformly distributed around the top of the elastic push rod as the center to form a plurality of concentric circular rings, and the distribution density of each concentric circular ring is consistent.

[0012] Furthermore, thin film pressure sensors are respectively provided before and after the anode sheet or cathode sheet on the plated spring sheet.

[0013] Compared with the prior art, the present invention has the following advantages: The present invention provides a pulse potential ablation catheter with strong adaptability, improved treatment effect and safety, reduced damage to surrounding tissues, more accurate imaging, improved comfort and convenience of surgical operation, and avoided excessive and incomplete ablation. Specifically, a flexible catheter, an elastic push rod, a pulse ablation unit, a hemispherical ring array ultrasound probe and other components are organically combined to form a single-ball electrical ablation structure with multi-size adaptability to better meet treatment needs, improve treatment effects, and reduce damage to patients; it integrates multi-element ultrasound imaging, magnetic positioning 3D navigation, and pulse electric field ablation, wherein the magnetic positioning 3D navigation provides 3D position and direction for multi-element ultrasound imaging; the electrodes of the pulse ablation unit are evenly distributed to prevent excessive concentration of ablation energy from causing ablation scabs and bubbles during the ablation process; the ultrasonic multi-element distribution at the catheter tip provides a new imaging reference angle that is different from the past and is closer to the surgical procedure. The device provides patients with intuitive imaging experience and is more ergonomic than previous side-view ultrasound imaging probes; the electrode column and coated guide wire or anode piece, cathode piece and coated spring piece and other components are independently connected, which means that each electrode component can work independently without affecting each other, thereby achieving more accurate energy transmission and ablation control, providing higher safety and effect for medical surgery; the design of the electrode column and coated guide wire adopts a multi-channel design, which can realize multi-channel simultaneous discharge and improve the treatment effect; the setting of the thin film pressure sensor can detect the degree of contact between the electrode and the human tissue, provide a reference for the energy and time of pulse ablation during surgery, and avoid excessive ablation and incomplete ablation. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is the ablation surgery handle used in the present invention.

[0015] Figure 2 It is a structural diagram of embodiment 1 of the present invention.

[0016] Figure 3 It is a schematic diagram of the operation of embodiment 1 of the present invention.

[0017] Figure 4 It is a structural diagram of embodiment 2 of the present invention.

[0018] Figure 5 It is a schematic diagram of the operation of embodiment 2 of the present invention.

[0019] Figure 6 It is a structural diagram of embodiment 3 of the present invention.

[0020] Figure 7 It is a schematic diagram of the operation of embodiment 3 of the present invention.

[0021] Figure 8 It is a structural schematic diagram of the hemispherical ring array ultrasonic probe of the present invention.

[0022] Figure numerals: 1. flexible catheter; 2. elastic push rod; 3. pulse ablation part; 31. coated guide wire; 32. electrode column; 33. coated spring; 34. anode plate; 35. cathode plate; 36. thin film pressure sensor; 37. shaping wire; 4. operating handle; 5. hemispherical ring array ultrasound probe; 51. ultrasound array element; 6. fixing ring. DETAILED DESCRIPTION

[0023] The embodiments of the present invention are described in further detail below in conjunction with the accompanying drawings.

[0024] A pulse potential ablation catheter, which is controlled by a remote host and provides pulse energy, comprises a flexible catheter 1, an elastic push rod 2, and a pulse ablation part 3, such as Figure 1 As shown, the elastic push rod 2 is the inner core of the flexible catheter 1 and is pushed and pulled by the distal operating handle 4. The front and rear ends of the part of the elastic push rod 2 extending out of the flexible catheter 1 are respectively fixed with a hemispherical ring array ultrasound probe 5 and a fixed ring 6 with a built-in magnetic positioning sensor. The pulse ablation part 3 is spherically distributed in the extended part of the elastic push rod 2 and is respectively bundled and fixed to the hemispherical ring array ultrasound probe 5 and the fixed ring 6. The hemispherical ring array ultrasound probe 5 wraps the top end of the elastic push rod 2 in the hemispherical structure.

[0025] The elastic push rod 2 is used to control the retraction and extension movement of the ablation balloon, thereby achieving precise control and adjustment of the ablation balloon during the ablation process, ensuring the safety and effectiveness of the operation.

[0026] The flexible catheter 1 is used to guide the operation, making it more flexible, convenient and accurate in actual operation.

[0027] The magnetic positioning sensor is used to bundle the coated guide wire 31 or the coated shrapnel 33 and fix their positions to prevent misalignment or damage to surrounding tissues during operation. The principle of the magnetic positioning sensor is: as a magnetic positioning navigation, a defined electromagnetic field is generated, and an electromagnetic micro sensor is tracked in the field. Specifically, a field generator is placed above, below or around the operating table, and the field generator emits a low-intensity, changing electromagnetic field to determine the measurement volume; when the sensor enters the electromagnetic field, a small current is induced inside the sensor, and these currents are relayed to the sensor interface unit (SIU), where they are amplified and digitized into signals, and the signals are transmitted to the system control unit (SCU), which calculates the position and direction of each sensor and converts them. The tracking data is transmitted to the host application interface for real-time navigation relative to the patient's image set. The magnetic positioning sensor can obtain the three-dimensional coordinates of two points, and thereby calculate the angle between the catheter and the XYZ axis, thereby obtaining the position and direction of the catheter. The outer diameter of the magnetic positioning sensor can be 0.4-3mm, the length can be 1-10mm, and it is composed of 3 mutually perpendicular coils and wires.

[0028] Since the catheter is relatively thin and has to pass through tortuous blood vessels, the ultrasonic signal and the magnetic positioning signal may interfere with each other during the dual transmission process. Therefore, a shielding layer and a protective layer are arranged between the transmission lines inside the catheter.

[0029] Example 1

[0030] like Figure 2 , 3 As shown, the pulse ablation part 3 is woven into a sphere by 32 independent coated guide wires 31 equidistantly woven vertically and horizontally. Each bundle of coated guide wires 31 is provided with an electrode column 32 with independent positive and negative electrodes, and the 32 electrode columns 32 are evenly distributed. The electrode column 32 is used to release pulses and transmit them to the part that needs ablation, so as to achieve a therapeutic effect. The coated guide wire 31 is used to conduct current, and its surface coating helps to insulate, thereby improving the current conduction efficiency and reducing damage to surrounding tissues.

[0031] As the top part of the whole device, the hemispherical ring array probe 5 is mainly made of PMCU piezoelectric ceramics, specifically, it can be lead zirconate titanate PZT or lead magnesium niobate PMN-PT, and its structure includes an acoustic lens layer, a matching layer, a piezoelectric ceramic layer, a backing, etc. The hemispherical ring array ultrasound probe 5 can receive the voltage signal emitted by the host and convert it into an ultrasonic signal, which is then transmitted to the human tissue, and then the echo sound signals of different intensities are reflected by different tissues of the human body, and then converted into corresponding electrical signals, and finally amplified, filtered, noise reduced, AD converted, and digital image processed to generate an image of the human tissue. The multi-element hemispherical ring array can generate multiple two-dimensional images of the target position, thereby completing three-dimensional imaging. The hemispherical ring array ultrasound probe 5 is connected to the host via a signal line and a ground line, and the cable can be an electronic coaxial line or FPC, etc.

[0032] The round head at the top of the hemispherical annular array ultrasound probe 5 protects tissues during ablation operations, and the hemispherical structure can seal and protect internal components, and also has the function of connecting the coated guide wire 31 or the coated spring sheet 33 .

[0033] Furthermore, if Figure 8 As shown, the hemispherical ring array ultrasonic probe 5 is composed of a number of ultrasonic array elements 51 uniformly distributed around the top of the elastic push rod 2 to form a number of concentric rings, and the distribution density of each concentric ring is consistent. Specifically, five layers of concentric rings are arranged from the top of the hemispherical structure to the outside, and the number of ultrasonic array elements 51 arranged from the top to the outside of each layer of concentric rings is 6, 10, 14, 18, and 22, respectively, so as to ensure uniform coverage of the sound field during ultrasonic imaging, thereby improving the imaging quality and resolution. A single ultrasonic array element 51 is a capacitive micromachined ultrasonic sensor, which constructs the sound field distribution data by solving the radiated sound field of a single ultrasonic array element 51 and spatially superimposing the sound pressure of N array elements. The displacement field formula of isotropic medium elastic wave is: ;in, is the sound pressure at a certain point in time, Represents spatial position and time respectively. In the Cartesian coordinate system The second-order partial derivative of is the speed of sound, For body force.

[0034] The ultrasound focused imaging algorithm is applied to the hemispherical matrix module. The principle is mainly based on the unique propagation characteristics of sound waves on the spherical surface. By designing a specific sound wave transmitting and receiving array, and using time adjustment to control the propagation path and focus position of the sound wave. This process combines matrix data and non-steady-state filtering to construct a non-steady-state phase shift factor, and then applies the imaging algorithm to convert this data into a visual image. At the same time, factors such as sound wave attenuation, scattering, and multiple reflections are considered for correction and optimization to achieve accurate imaging of the external vascular structure of the sphere.

[0035] Example 2

[0036] The pulse ablation section 3 in the second embodiment is completely different from that in the first embodiment.

[0037] like Figure 4 , 5 As shown, the pulse ablation part 3 is formed into a sphere by evenly distributed eight arc-shaped coated spring pieces 33 , and each coated spring piece 33 is provided with an anode piece 34 and a cathode piece 35 .

[0038] The anode plate 34 or cathode plate 35 is used to release pulses and transmit them to the site requiring ablation.

[0039] The plated spring piece 33 is used to enhance the electrical energy conduction effect and strengthen the spherical structure, and to perform plated insulation to reduce damage to surrounding tissues. Preferably, a thin film pressure sensor 36 is provided before and after the anode piece 34 or cathode piece 35 on the plated spring piece 33, respectively.

[0040] The thin film pressure sensor 36 is a resistive pressure sensor or a capacitive pressure sensor, made of piezoelectric polyvinylidene fluoride PVDF, sputtered metallized film such as copper, nickel, gold and other alloys, silver ink screen-printed electrodes, and an elastomer on the back side, such as PDMS, polyethylene terephthalate, PI substrate film and single-sided double-sided tape or epoxy resin. After being subjected to contact resistance, an electrical signal (charge or voltage) will be generated between the upper and lower electrode surfaces of the piezoelectric film, and it is proportional to the force received, and its thickness is 0.02-0.4mm. When the force sensed by the thin film pressure sensor 36 is within a suitable threshold, it means that the electrode is well attached to the human tissue and the force is appropriate, and pulse discharge ablation can be performed; when the contact force is too small, it means that the electrode is not firmly attached, which may cause meaningless ablation; when the contact force is too large, it may damage the blood vessel, and the force of the catheter needs to be adjusted to a suitable level before ablation.

[0041] Example 3

[0042] On the basis of Example 2, Figure 6 , 7 As shown, a shaping wire 37 is provided between adjacent plated spring sheets 33 to ensure the spherical stability of the pulse ablation portion 3. The shaping wire 37 has poor elasticity and plasticity and is used to maintain the spherical stability of the expanded ablation balloon when it contacts the irregular inner wall.

[0043] The above description is only a preferred embodiment of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and modifications without departing from the concept of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A pulse potential ablation catheter, which is controlled by a remote host and provides pulse energy, characterized in that: It includes a flexible catheter, an elastic push rod, and a pulse ablation part. The elastic push rod is the inner core of the flexible catheter and is pushed and pulled by a distal operating handle. The front and rear ends of the elastic push rod extending out of the flexible catheter are respectively fixed with a hemispherical ring array ultrasound probe and a fixed ring with a built-in magnetic positioning sensor. The pulse ablation part is spherically distributed on the extended part of the elastic push rod and is respectively bundled and fixed on the hemispherical ring array ultrasound probe and the fixed ring. The hemispherical ring array ultrasound probe wraps the top end of the elastic push rod in the hemispherical structure.

2. The pulse potential ablation catheter according to claim 1, characterized in that: The pulse ablation part is formed into a spherical shape by 32 independent coated guide wires woven in an equidistant manner in the vertical and horizontal directions. Each bundle of coated guide wires is provided with an independent positive and negative electrode column, and the 32 electrode columns are evenly distributed.

3. The pulse potential ablation catheter according to claim 1, characterized in that: The pulse ablation part is formed into a sphere by evenly distributing 8 arc-shaped coated spring pieces, and an anode piece and a cathode piece are respectively arranged on each coated spring piece.

4. The pulse potential ablation catheter according to claim 3, characterized in that: A shaping wire is arranged between adjacent plated spring sheets to ensure the pulse ablation portion maintains the stability of the spherical shape.

5. The pulse potential ablation catheter according to claim 1, characterized in that: The hemispherical ring array ultrasonic probe is composed of a plurality of ultrasonic array elements uniformly distributed around the top of the elastic push rod as the center to form a plurality of concentric rings, and the distribution density of each concentric ring is consistent.

6. A pulse potential ablation catheter according to claim 3 or 4, characterized in that: Thin film pressure sensors are respectively arranged before and after the anode sheet or cathode sheet on the plated spring sheet.

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