An electric pulse ablation system for treating atrial fibrillation and a method of using the same

Abstract

The present invention relates to the field of medical devices, and in particular to an electric pulse ablation system for treating atrial fibrillation and a method of using the same. The existing radiofrequency ablation or cryoablation for treating atrial fibrillation is not effective and is prone to cause pulmonary vein stenosis and phrenic nerve damage, and balloon dilatation and stent implantation are required later. The present invention provides an electric pulse ablation system for treating atrial fibrillation, including an ablation surgical clamp connected to a power cord and a high-voltage electric pulse generating device, the ablation surgical clamp includes a connecting rod and a clamp body and a grip disposed at both ends thereof, the clamp body includes a fixed clamp and a movable clamp disposed at the end of the connecting rod, and an arc-shaped clamping section is extended from each of the fixed clamp and the movable clamp to form a clamping hole that can be opened and closed, and an electrode sheet group is arranged on two clamping sections corresponding to one side of the clamping hole and / or the inner edge of the clamping hole, the grip is provided with an unlocking mechanism for opening the clamping hole, and the connecting rod is provided with a locking mechanism for closing the clamping hole. The present invention can perform comprehensive ablation on the atrial fibrillation area and effectively block the transmission of ectopic signals.

Description

Technical Field

[0001] The present invention relates to the field of medical devices, and in particular to an electric pulse ablation system for treating atrial fibrillation and a use method thereof. Background Art

[0002] One of the main mechanisms of paroxysmal atrial fibrillation (AF), especially AF without organic heart disease, is triggered by rapid electrical excitation from the pulmonary vein muscle sleeve. For this reason, surgical or catheter radiofrequency ablation can be used to isolate the anatomical connection or electrical connection (conduction) relationship between the pulmonary vein muscle sleeve and the atrium to achieve the purpose of radical cure. As a result, catheter ablation has become an important part of the overall treatment of AF, and the recommendation level in medical guidelines has been continuously improved. Currently, radiofrequency ablation or cryoablation is commonly used in clinical practice. The conventional ablation energy relies on time-dependent conduction heating or cooling. The extreme temperature of radiofrequency (60°C) or cryotherapy (-160°C) will ablate all tissues in the target area. When working, the catheter emits high-frequency electromagnetic waves (RF energy) after reaching the designated position along the inside of the blood vessel through the vascular cannula, and a circle of ablation points is made along the opening of the pulmonary vein. By increasing or decreasing the temperature, the atrial muscle is necrotized to produce a circular scar, isolating the ectopic signal source from the outside, and then the heart resumes regular beating. However, the formation of scars can easily lead to pulmonary vein stenosis after surgery. Cryoablation can also easily cause phrenic nerve damage, with serious consequences. Patients have to undergo follow-up treatments such as balloon dilatation and stent implantation.

[0003] Nanosecond pulsed electrical field (NsPEF) ablation is a new electric field energy source that can be selected. It forms a local high voltage difference by sending biphasic high-voltage ultra-short nanosecond pulse electric fields. It is a new ablation method that causes irreversible electrical damage to the myocardium through electric field energy. NsPEF can transmit different electric field energies according to the resistance of different cells and tissue types, and has good tissue selectivity. Moreover, NsPEF is a non-thermal ablation technology. The damage mechanism is nanosecond-level high-voltage ultra-short high-frequency electric pulses. It destroys the atrial fibrillation triggering foci in the pulmonary veins and vestibule and partially eliminates the atrial fibrillation matrix in a non-thermal electrical ablation manner, causing micropores and programmed cell membrane death in the area, thereby blocking the transmission of ectopic signals. Summary of the invention

[0004] The technical problems to be solved and the technical tasks proposed by the present invention are to overcome the many problems that the existing radiofrequency ablation or cryoablation will ablate all tissues in the target area and easily form pulmonary vein stenosis. Cryoablation is also prone to cause phrenic nerve damage and requires subsequent balloon dilatation and stent implantation treatment. The present invention provides an electric pulse ablation system for treating atrial fibrillation and a method of using the same. The electric pulse ablation system uses nanosecond pulsed electric field (NsPEF) for annular catheter ablation, which has uniformly distributed irreversible transmural damage to myocardial tissue and effectively reduces the risk of fibrous scars; selective ablation of myocardial tissue can be performed to protect surrounding tissues from unnecessary damage; the electric field is released in a very short time for ablation, and the heating temperature is controlled within the normal temperature range without the risk of thermal damage; ③ ablation will not produce coagulative necrosis, and the risk of pulmonary vein (PV) stenosis is reduced.

[0005] The technical solution adopted by the present invention to solve the technical problem is: an electric pulse ablation system for treating atrial fibrillation, including an ablation surgical clamp connected to a power cord and a high-voltage electric pulse generating device, the ablation surgical clamp includes a connecting rod and a clamp body and a grip arranged at both ends thereof, an electrode sheet group consisting of a plurality of electrode sheets is arranged on the clamp body, and the electrode sheet group is connected to the power cord, and is characterized in that the clamp body includes a fixed clamp and a movable clamp arranged at the end of the connecting rod, the fixed clamp is fixed to the end of the connecting rod, and the movable clamp is movably arranged in a slide groove at the end of the connecting rod, and the fixed clamp is fixed to the end of the connecting rod. An arc-shaped clamping section extends from each of the fixed clamp and the movable clamp, and the two clamping sections form a clamping hole that can be opened and closed movably. The electrode sheet group includes a first electrode sheet group distributed on two clamping sections corresponding to one side of the clamping hole and / or a second electrode sheet group distributed on two clamping sections corresponding to the inner edge of the clamping hole. The handle is provided with an unlocking mechanism that can drive the movable clamp to move back to the fixed clamp to open the clamping hole, and the connecting rod is provided with a locking mechanism at one end of the clamp body that can drive the movable clamp to move toward the fixed clamp to close the clamping hole. The present invention matches the clamp body with an arc-shaped clamping section with the area where the atrial fibrillation lesion is located, and at the same time applies a larger range of electric fields to destroy the atrial fibrillation triggering lesions in the pulmonary veins and vestibule and partially eliminate the atrial fibrillation matrix, so that the ablation is more comprehensive and has no dead angles, thereby achieving a better effect of blocking the transmission of ectopic signals. When working, two arc-shaped clamping sections form a clamping hole that can be opened and closed. The clamping section where the movable clamp is located opens the clamping hole or tightens the clamping hole by translational movement to match the shape of the pulmonary vein. The two clamping sections are provided with a first electrode sheet group and / or a second electrode sheet group, which are used to apply electric field ablation to the atrial surface close to the pulmonary vein and the root of the pulmonary vein and the part between the two: the electrodes of the first electrode sheet group are distributed on the two clamping sections on one side of the clamping hole, and the clamp body clamps the pulmonary vein so that the side where the first electrode sheet group is located fits the atrial surface close to the pulmonary vein. When working, a high-voltage electric field can be applied to the atrial surface that is in close contact by switching the polarity between each two adjacent electrodes in the first electrode sheet group for ablation; the electrodes of the second electrode sheet group are distributed on the inner edge of the clamping hole, and a high-voltage electric field is applied to the root of the pulmonary vein by switching the polarity between each two adjacent electrodes distributed around the inner edge of the clamping hole. Ablation is performed in a circle; when two electrode groups exist at the same time, the two adjacent electrode groups belonging to the first electrode group and the second electrode group can also apply a high-voltage electric field to the position between the two circular ablations on the atrial surface and the root of the pulmonary vein by switching the polarity positively and negatively. A high-voltage electric field can be applied between every two adjacent electrode groups along the clamping hole by switching the polarity positively and negatively, so as to achieve a superimposed ablation in a circle at right angles to the atrium and the pulmonary vein. Three groups of electric field ablations can be applied at different positions between the first electrode group, the second electrode group, and the first electrode group and the second electrode group, so as to achieve comprehensive and thorough electric field ablation without dead angles from the atrial surface where the clamp body is located to the adjacent pulmonary veins, thereby ensuring the ablation range and effect.

[0006] As a further improvement and supplement to the above technical solution, the present invention adopts the following technical measures: the first electrode sheet group includes 8 to 16 electrode sheets extending along the arc bend of the clamping section, and the electrode sheets on the fixed clamp and the movable clamp are equally and symmetrically arranged; the second electrode sheet group includes 6 to 14 electrode sheets extending along the arc bend of the clamping section, and the electrode sheets on the fixed clamp and the movable clamp are equally and symmetrically arranged. The electric field ablation effect is ensured by a sufficient number of symmetrical first electrode sheet groups and second electrode sheet groups on the two clamping sections. In actual use, it is preferred that the first electrode sheet group is 12 electrode sheets, 6 on each clamping section; the second electrode sheet group is 10 electrode sheets, 5 on each clamping section.

[0007] The unlocking mechanism includes a turning handle, a swing rod and a steel cable. The upper end of the turning handle is connected to the handle by rotation. One end of the swing rod is connected to the middle of the turning handle by rotation. The other end is slidably arranged in the limit groove on the handle. One end of the steel cable passes through the handle and the connecting rod to pull the movable clamp. The locking mechanism includes a spring arranged in the slide groove. The front end of the spring is limited to touch the movable clamp, and the rear end of the spring is limited to touch one end of the slide groove. Since the upper end of the turning handle is connected to the handle by rotation, pressing the turning handle downward can make it rotate inward around the rotating connection end, and at the same time push the swing rod to move. The two ends of the swing rod are respectively limited by the turning handle and the upper limit groove of the handle. One end of the swing rod slides in the limit groove, pulling the steel cable, and the steel cable drives the movable clamp to move backward to open the clamping hole, and the spring is compressed. When the turning handle is released, the spring stretches and resets to push the movable clamp to move forward to return to its position, and the clamping hole is closed and tightened again. The movable clamp moves forward to pull the swing rod to slide in the limit groove in the opposite direction, and the displacement of the swing rod pushes the turning handle to rotate outward to return to its position.

[0008] The connecting rod is composed of a long rod and a joint seat, one end of the long rod is rotatably connected to the handle, the fixed clamp and the movable clamp are arranged on the joint seat, and the slide groove is arranged on the joint seat. The connecting rod is divided into two parts, consisting of a long rod and a joint seat. When working, the handle does not move, and the long rod can adjust the direction angle by rotating 360° to ensure that the clamp body can smoothly enter the ablation site, so as to ensure that the electrode sheet group on the subsequent clamp body can accurately fit in place for electric field ablation.

[0009] The clamping hole is elliptical or circular. The elliptical clamping hole can better fit and clamp the pulmonary vein near the surface of the atrium, improve the close fit between the electrode sheet on the clamp body and the ablation tissue, and achieve a better ablation effect.

[0010] A method for using an electric pulse ablation system for treating atrial fibrillation, characterized by comprising the following steps performed in sequence:

[0011] (1) Turn the connecting rod to ensure that the clamp body can smoothly enter the ablation position;

[0012] (2) Open the clamping hole and operate the unlocking mechanism to drive the movable clamp to move back to the fixed clamp, and the elliptical clamping hole opens;

[0013] (3) Close the clamping hole, loosen the handle, and the spring of the locking mechanism drives the movable clamp to move toward the fixed clamp to reset, and the clamping hole is closed;

[0014] (4) Applying electric pulses: the first group of electric pulses, the second group of electric pulses and the third group of electric pulses applied individually or in combination, the first group of electric pulses being two electric pulses applied by switching forwards and backwards between two adjacent electrode sheets on the first group of electric pulse electrode sheets; the second group of electric pulses being two electric pulses applied by switching forwards and backwards between two adjacent electrode sheets on the second group of electric pulse electrode sheets; the third group of electric pulses being two electric pulses applied by switching forwards and backwards between adjacent electrode sheets on the first group of electric pulse electrode sheets and the second group of electric pulse sheets.

[0015] The method of use described in the present invention achieves comprehensive and thorough electric field ablation from the atrial surface where the clamp body is located to the adjacent pulmonary veins by applying three groups of electric field ablation at different positions, namely, the first electrode group, the second electrode group, and between the first electrode group and the second electrode group, thereby ensuring a continuous ablation range and a better ablation effect.

[0016] The present invention provides an electric pulse ablation system for treating atrial fibrillation and a method of using the same. The system matches a clamp body with an arc-shaped clamping section to an area where the atrial fibrillation lesion is located, and applies an electric field over a wider range to destroy the atrial fibrillation triggering lesions in the pulmonary veins and vestibule and partially eliminate the atrial fibrillation matrix. The ablation is more comprehensive and has no dead angles, thereby achieving a better effect of blocking the transmission of ectopic signals. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 : Overall schematic diagram of the present invention.

[0018] Figure 2 : Schematic diagram of surgical clamp described in the present invention.

[0019] Figure 3 : A cross-sectional view of the surgical clamp described in the present invention.

[0020] Figure 4 : Schematic diagram of the three groups of electric pulses described in the present invention.

[0021] Figure 5 : Circuit topology diagram of nanosecond pulse electric field generating device.

[0022] In the figure: 1. power cord, 2. high voltage electric pulse generating device, 3. connecting rod, 3-1. long rod, 3-2. joint seat, 3-3. slide groove, 4. clamp body, 4-1. fixed clamp, 4-2. movable clamp, 5. handle, 5-1. limit groove, 6. first electrode sheet group, 7. second electrode sheet group, 8. electrode sheet, 9-1. turning handle, 9-2. rocker arm, 9-3. steel cable, 10. clamping hole, 11. spring. DETAILED DESCRIPTION

[0023] The present invention will be further described below in conjunction with the accompanying drawings and specific implementation methods.

[0024] like Figures 1 to 3As shown, an electric pulse ablation system for treating atrial fibrillation includes an ablation surgical clamp connected to a power cord 1 and a high-voltage electric pulse generating device 2. The high-voltage electric pulse generating device 2 in this embodiment is a nanosecond pulse electric field generating device. The ablation surgical clamp includes a connecting rod 3 and a clamp body 4 and a grip 5 arranged at both ends thereof. The clamp body 4 is provided with a first electrode sheet group 6 and a second electrode sheet group 7 composed of a plurality of electrode sheets. Each electrode sheet in the two electrode sheet groups is connected to the power cord 1. The clamp body 4 includes a fixed clamp 4-1 and a movable clamp 4-2 arranged at the end of the connecting rod 3. The fixed clamp 4- 1 is fixed to the end of the connecting rod 3, and the movable clamp 4-2 is movably arranged in the slide groove at the end of the connecting rod 3. An arc-shaped clamping section is extended from the fixed clamp 4-1 and the movable clamp 4-2 respectively, and the two clamping sections constitute an elliptical clamping hole 10 that can be opened and closed. The first electrode sheet group 6 is 12 electrode sheets 8 distributed on the two clamping sections on one side of the clamping hole 10, and 6 electrode sheets are distributed along the arc on each clamping section. The two clamping sections are symmetrically arranged. As shown in the figure, the electrode sheets are numbered 1 / 2 / 3...12. The second electrode sheet group 7 is divided into two clamping sections on the inner edge of the clamping hole 10. There are 10 electrode sheets 8 of the cloth, 5 of which are distributed along the arc on each clamping section, and are symmetrically arranged on the two clamping sections. As shown in the figure, the electrode sheets are numbered 13 / 14 / 15...22; the connecting rod 3 is composed of a long rod 3-1 and a joint seat 3-2, one end of the long rod 3-1 is rotatably connected to the handle 5, the fixed clamp 4-1 and the movable clamp 4-2 are arranged on the joint seat 3-2, and the slide groove 3-3 is arranged on the joint seat 3-2; the handle 5 is provided with an unlocking mechanism that can drive the movable clamp 4-2 to move back to the fixed clamp 4-1 to open the clamping hole 10, which includes a turning handle 9-1 and The rocker arm 9-2 and the steel cable 9-3, the upper end of the turning handle 9-1 is rotatably connected to the grip 5, one end of the rocker arm 9-2 is rotatably connected to the middle of the turning handle 9-1, and the other end is slidably arranged in the limiting groove 5-1 on the grip 5, one end of the steel cable 9-3 passes through the grip 5 and the connecting rod 3 to pull the movable clamp 4-2; one end of the connecting rod 3 docking with the clamp body 4 is provided with a locking mechanism which can drive the movable clamp 4-2 toward the fixed clamp 4-1 to move and close the clamping hole 10, which includes a spring 11 arranged in the slide groove, the front end of the spring 11 limits the top contact with the movable clamp 4-2, and the rear end of the spring 11 limits the top contact with one end of the slide groove.

[0025] A method for using an electric pulse ablation system for treating atrial fibrillation comprises the following steps performed in sequence:

[0026] (1) Rotate the connecting rod 3 to adjust the direction angle to ensure that the clamp body 4 can smoothly enter the ablation position;

[0027] (2) Open the clamping hole 10, operate the unlocking mechanism to drive the movable clamp 4-2 to move away from the fixed clamp 4-1, the clamping hole 10 opens, and the clamp body 4 enters from the narrow opening of the patient's heart pulmonary vein to surround the entire pulmonary vein;

[0028] (3) Close the clamping hole 10, loosen the turning handle 9-1, and the spring 11 of the locking mechanism drives the movable clamp 4-2 to move toward the fixed clamp 4-1 to reset, and the clamping hole 10 is closed;

[0029] (4) Applying electric pulses: Apply the first group of electric pulses, the second group of electric pulses and the third group of electric pulses in sequence. The first group of electric pulses is two electric pulses applied by switching between two adjacent electrode sheets on the first group of electric pulse electrode sheets (see Figure 4 A in the figure refers to the first group of pulsed electric fields applied on the surface of the atrium near the pulmonary veins. First, 1-2 applies a pulse, then 1-2 switches the electrode polarity forward and reverse and applies it again to avoid local myocardial rigidity. 2-3 applies the next pulse, 2-3 switches the electrode polarity forward and reverse and applies it again, and so on until 12-1 completes the pulse application. The second group of electric pulses is two electric pulses applied by switching forward and reverse between two adjacent electrode sheets on the second group of electric pulse electrode sheets (see Figure 4 B in the figure), specifically, the second set of pulsed electric fields is applied to the root of the pulmonary vein, first applying a pulse at 13-14, then applying it again after switching the electrode polarity at 13-14, and so on until the pulse application at 22-13 is completed; the third set of electric pulses is two electric pulses applied by switching the electrode sheet group of the first set of electric pulses and the adjacent electrode sheets of the second set of electric pulses (see Figure 4 C in the figure) is to form a superimposed electric field at right angles between the atrium and the pulmonary vein, first 1-13, then 13-2, 2-14, and 14-3, respectively, applying two pulses of positive and negative switching polarity. Through the aforementioned three sets of combined pulse electric field ablation, a full range of ablation without dead angles is formed to ensure the ablation range and effect.

[0030] In addition, Figure 5 As shown, the nanosecond pulse electric field generating device in this embodiment adopts an H-bridge topology to generate positive and negative pulses, and cooperates with a matrix switch structure to achieve the required electric field application method. The specific implementation method of the circuit is as follows Figure 4As shown, first, the power supply can be set to the required voltage value, and the energy storage capacitor C is charged through the current limiting resistor R. When the energy storage capacitor is fully charged, the control module drives the switch to work. Q1 and Q4 are a group, and Q2 and Q3 are a group, forming positive and negative pulses. The matrix switch array can send a signal from the control module to turn on specific electrodes and release pulses as needed. The power supply output voltage can be arbitrarily set to DC 0-1000V, and the output mode is constant current output. Compared with constant voltage output, it can speed up the charging time of the energy storage capacitor. Switches Q1, Q2, Q3, and Q4 can use MOS tubes or IGBT tubes. The control module uses FGPA as the main control chip to control the conduction time of the switch tube. The matrix switch array is closed accordingly according to the electric pulse application method, and the two electrodes that need to implement the pulse are turned on, thereby releasing the pulse.

Claims

1. An electric pulse ablation system for treating atrial fibrillation, comprising an ablation surgical clamp connected to a power line (1) and a high-voltage electric pulse generating device (2), the ablation surgical clamp comprising a connecting rod (3) and a clamp body (4) and a grip (5) arranged at both ends thereof, the clamp body (4) being provided with an electrode sheet group consisting of a plurality of electrode sheets, the electrode sheet group being connected to the power line (1), and characterized in that The clamp body (4) comprises a fixed clamp (4-1) and a movable clamp (4-2) which are arranged at the end of the connecting rod (3), the fixed clamp (4-1) is fixed to the end of the connecting rod (3), and the movable clamp (4-2) is movably arranged in a slide groove (3-3) at the end of the connecting rod (3), and an arc-shaped curved clamping section is extended from each of the fixed clamp (4-1) and the movable clamp (4-2), and the two clamping sections form a clamping hole (10) that can be movably opened and closed, and the electrode sheet group comprises a first electrode sheet group (6) distributed on two clamping sections corresponding to one side of the clamping hole (10) and a second electrode sheet group (6) corresponding to one side of the clamping hole (10). The second electrode sheet group (7) distributed on the two clamping sections at the inner edge of the hole (10) and the two electric pulses applied by switching the polarity between the adjacent electrode sheets of the first electrode sheet group (6) and the second electrode sheet group (7) form a superimposed electric field in the right angle direction between the atrium and the pulmonary vein. The handle (5) is provided with an unlocking mechanism capable of driving the movable clamp (4-2) to move away from the fixed clamp (4-1) to open the clamping hole (10), and the connecting rod (3) is provided with a locking mechanism at one end of the clamp body (4) to drive the movable clamp (4-2) to move toward the fixed clamp (4-1) to close the clamping hole (10).

2. The electric pulse ablation system for treating atrial fibrillation according to claim 1, characterized in that The first electrode sheet group (6) comprises 8 to 16 electrode sheets (8) extending along the arc-shaped bend of the clamping section, and the electrode sheets (8) on the fixed clamp (4-1) and the movable clamp (4-2) are arranged in equal quantities and symmetrically; the second electrode sheet group (7) comprises 6 to 14 electrode sheets (8) extending along the arc-shaped bend of the clamping section, and the electrode sheets (8) on the fixed clamp (4-1) and the movable clamp (4-2) are arranged in equal quantities and symmetrically.

3. The electric pulse ablation system for treating atrial fibrillation according to claim 1 or 2, characterized in that The unlocking mechanism comprises a turning handle (9-1), a swing rod (9-2) and a steel cable (9-3); the upper end of the turning handle (9-1) is rotatably connected to the handle (5); one end of the swing rod (9-2) is rotatably connected to the middle of the turning handle (9-1), and the other end is slidably arranged in a limiting groove (5-1) on the handle (5); one end of the steel cable (9-3) passes through the handle (5) and the connecting rod (3) to pull the movable clamp (4-2); the locking mechanism comprises a spring (11) arranged in the slide groove (3-3); the front end of the spring (11) is limited to contact the movable clamp (4-2), and the rear end of the spring (11) is limited to contact one end of the slide groove.

4. The electric pulse ablation system for treating atrial fibrillation according to claim 1 or 2, characterized in that The connecting rod (3) is composed of a long rod (3-1) and a joint seat (3-2) connected together, one end of the long rod (3-1) is rotatably connected to the handle (5), the fixed clamp (4-1) and the movable clamp (4-2) are arranged on the joint seat (3-2), and the sliding groove (3-3) is arranged on the joint seat (3-2).

5. The electric pulse ablation system for treating atrial fibrillation according to claim 1, characterized in that The clamping hole (10) is oval or circular.

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