CN114948174A

CN114948174A - Intelligent pulsed electric field ablation system for controlling output channel

Info

Publication number: CN114948174A
Application number: CN202210583013.0A
Authority: CN
Inventors: 黄雍俊; 朱显钊; 魏少勋; 陶亮; 肖平
Original assignee: Sichuan Jinjiang Electronic Science and Technology Co Ltd
Current assignee: Sichuan Jinjiang Electronic Science and Technology Co Ltd
Priority date: 2022-05-26
Filing date: 2022-05-26
Publication date: 2022-08-30

Abstract

The invention belongs to the technical field of pulsed electric field ablation, and particularly relates to an intelligent pulsed electric field ablation system for controlling an output channel. The system comprises a pulse electric field ablation instrument and a multi-electrode pulse ablation catheter, wherein the multi-electrode pulse ablation catheter opens or closes a channel for outputting a high-voltage pulse signal according to a detection result of the pulse electric field ablation instrument; the multi-electrode pulse ablation catheter is also used for detecting the acquisition of impedance signals, PH value acquisition signals and/or dielectric constant signals at the catheter; the pulse electric field ablation instrument judges the ablation state of a high-voltage pulse signal acting on human tissues through one or more detection results of impedance detection, pH value detection and dielectric constant detection, and the ablation state is used for visual marking. The system reflects the state of human tissue at each electrode in the current high-voltage pulse ablation according to the change conditions of the impedance change rate, the PH value and the dielectric constant of the electrode, and carries out marking and intelligent switching according to the state.

Description

Intelligent pulsed electric field ablation system for controlling output channel

Technical Field

The invention belongs to the technical field of pulsed electric field ablation, and particularly relates to an intelligent pulsed electric field ablation system for controlling an output channel.

Background

The existing technology for treating tachyarrhythmia usually adopts radiofrequency, freezing and other thermal ablation technologies. Wherein the radio frequency technology can generate a sine wave of fixed frequency. The generated radio frequency energy acts on the focus point needing to be treated through the radio frequency catheter or the radio frequency electrode, so that the effect of blocking or conditioning is achieved, and the treatment effect is further achieved. In the freeze ablation, heat is absorbed through the evaporation process of the liquid refrigerant in the freezing saccule, so that the temperature around an ablation target point is suddenly reduced. The tissue cells in the focus area are damaged or dead through low temperature, thereby achieving the purpose of treatment. The ablation techniques are limited by the heat pool effect in the clinical practical application, the full-layer transmural ablation target is difficult to achieve, and the ablation techniques do not have the selectivity of cells, so that non-target cells are ablated and damaged.

In view of the above drawbacks of thermal ablation techniques, pulsed electric field ablation techniques are gaining increasing attention as an athermal ablation technique. The pulsed electric field ablation technology is to generate a high-voltage pulsed electric field with the pulse width of millisecond, microsecond or even nanosecond, and release extremely high energy in a short time, so that a large number of irreversible micropores can be generated in cell membranes and even intracellular organelles such as endoplasmic reticulum, mitochondria, cell nucleus and the like. Further causing the apoptosis of the pathological cells, thereby achieving the expected treatment purpose.

In the application of treating the tachyarrhythmia, the adoption of the pulsed electric field ablation technology can selectively treat the myocardial cells without influencing other non-target cell tissues, and meanwhile, the method has the characteristics of complete full-layer ablation, accuracy, rapidness and coronary artery protection. Therefore, the pulsed electric field ablation technology is expected to be an ideal cardiac ablation means.

In the prior art, usually, an ablation device needs to be used in combination with an electrophysiology three-dimensional mapping system, the ablation device outputs energy to a focus to cause the focus to change, and the electrophysiology three-dimensional mapping system monitors an ablation process by acquiring signals, for example, the electrophysiology three-dimensional mapping system can mark an ablation point, so that an ablation position can be visually displayed, and an operator can timely adjust parameters of the ablation device and an ablation direction according to returned data displayed by the electrophysiology three-dimensional mapping system.

After the pulse electric field discharge ablation is adopted, pulse energy output is generally completed by the pulse electric field discharge between a plurality of electrodes instead of single-point ablation, so that the ablation effect is fed back through a pressure sensor under the condition of single-point ablation, the mode of performing ablation point marking on the electrophysiology three-dimensional mapping system is not suitable for the pulse electric field discharged between the plurality of electrodes, improvement needs to be performed on high-voltage pulse ablation, and a new system for feeding back the ablation effect is provided.

Disclosure of Invention

Aiming at the problem that the existing ablation point marking method of the electrophysiology three-dimensional mapping system cannot accurately reflect the multi-point ablation effect of the high-voltage pulse signals, the invention selects new parameters such as impedance value, PH value and dielectric constant, and reflects the state and effect of the high-voltage pulse ablation according to the change of the parameters, thereby providing the pulse electric field ablation system for intelligently controlling the output channel.

In order to achieve the above purpose, the invention provides the following technical scheme:

an intelligent pulsed electric field ablation system for controlling an output channel comprises a pulsed electric field ablation instrument and a multi-electrode pulsed ablation catheter,

the multi-electrode pulse ablation catheter opens or closes a channel for outputting a high-voltage pulse signal according to the detection result of the pulse electric field ablation instrument; the multi-electrode pulse ablation catheter is also used for acquiring impedance signals, PH value acquisition signals and/or dielectric constant signals at the catheter;

the pulsed electric field ablation instrument carries out impedance detection according to the impedance signal, carries out PH value detection according to the PH value acquisition signal, carries out dielectric constant detection according to the dielectric constant signal, and judges the ablation state of the high-voltage pulse signal after being applied to human tissues through one or more detection results of the impedance detection, the PH value detection and the dielectric constant detection, wherein the ablation state is used for visual marking.

In a preferred embodiment of the present invention, the ablation state includes an unperforated state and a perforated state, and when the ablation state is a perforated state, the channel outputting the high voltage pulse is closed, and when the ablation state is an unperforated state, the channel outputting the high voltage pulse is kept open.

As a preferable aspect of the present invention, the impedance detection includes detection of an impedance value and detection of an impedance change rate,

when the impedance value is in a first impedance threshold range and the impedance change rate is in a first change rate range, the electrode outputting the high-voltage pulse is in the blood pool and is not attached to human tissues;

and when the impedance value is in a second impedance threshold range and the impedance change rate is in a second change rate range, the electrode outputting the high-voltage pulse is attached to the human tissue.

As a preferred aspect of the present invention, a method for acquiring an impedance signal for impedance detection includes: and loading signals with the frequency of 2KHz to 200KHz to the electrode of the multi-electrode pulse ablation catheter, collecting return signals of the signals from 2KHz to 200KHz acting on the electrode, and converting the return signals into impedance signals through filtering treatment.

In a preferred embodiment of the present invention, the ablation state is perforation if the PH detection result indicates that the variation range is ± 0.5, on the premise that the electrode outputting the high voltage pulse is in contact with the human tissue.

In a preferred embodiment of the present invention, the ablation state is perforation if the result of the permittivity detection is within a predetermined permittivity range, on the premise that the electrode outputting the high voltage pulse is in contact with the human tissue.

As a preferred aspect of the present invention, a method for acquiring a permittivity signal for permittivity detection includes:

and (3) enabling the sinusoidal excitation signal to act on human tissues through the electrodes of the multi-electrode pulse ablation catheter, wherein the frequency range of the sinusoidal excitation signal is 5KHz-300MHz, and acquiring a complex impedance electric signal returned after the sinusoidal excitation signal with different frequencies acts on the human tissues, wherein the complex impedance electric signal is a dielectric constant signal.

In a preferred embodiment of the present invention, the ablation state is perforation if the PH detection result is within ± 0.5 when the electrode outputting the high voltage pulse is not in contact with the human tissue and the permittivity detection result is within a predetermined permittivity range.

In a preferred embodiment of the present invention, the ablation state is perforation if the impedance change rate, the PH change rate, and the permittivity change rate are stable.

As a preferable proposal of the invention, the invention also comprises a cardiac electrophysiology three-dimensional mapping system,

the cardiac electrophysiology three-dimensional mapping system is in communication connection with the pulsed electric field ablation instrument and is used for displaying an ablation state mark in a cardiac three-dimensional image;

the cardiac electrophysiology three-dimensional mapping system is also used for detecting key conducting signals from a sinoatrial node, an atrioventricular node or a his bundle and outputting the key conducting signals to the pulsed electric field ablator; and the pulsed electric field ablation instrument cuts off the channel of the high-voltage pulse signal related to the key conducting signal.

Compared with the prior art, the invention has the beneficial effects that:

the system reflects the state of human tissues at each electrode in the current high-voltage pulse ablation according to the impedance, the PH value and the dielectric constant of the electrode, and accurately reflects the multi-point ablation effect of the high-voltage pulse signal.

Drawings

Fig. 1 is a system connection block diagram of a pulsed electric field ablation system with intelligently controlled output channels according to embodiment 1 of the present invention;

FIG. 2 is a schematic block diagram of a pulsed electric field ablation system with intelligently controlled output channels according to example 1 of the present invention;

FIG. 3 is a schematic diagram showing the classification of the impedance detection scheme in example 1 of the present invention;

FIG. 4 is a schematic diagram of the detection of the time-sharing handover in embodiment 1 of the present invention;

fig. 5 is a schematic diagram of frequency division handover detection in embodiment 1 of the present invention;

FIG. 6 is a schematic diagram of fusion extraction detection in example 1 of the present invention;

FIG. 7 is a schematic diagram of a pH detection scheme in example 1 of the present invention;

FIG. 8 is a schematic view of a dielectric detection scheme in example 1 of the present invention;

FIG. 9 is a structural view of a variable configuration spherical multi-electrode pulsed electric field ablation catheter in accordance with example 1 of the present invention;

fig. 10 is an expanded view of the variable-configuration spherical multi-electrode pulsed electric field ablation catheter in example 1 of the present invention;

FIG. 11 is a schematic view of the expanded array of the variable-configuration spherical multi-electrode pulsed electric field ablation catheter in example 1 of the present invention;

fig. 12 is a schematic view of an annular multi-electrode pulsed electric field ablation catheter in embodiment 1 of the present invention;

fig. 13 is a schematic drawing of the ring-shaped multi-electrode pulsed electric field ablation catheter in example 1 of the present invention;

FIG. 14 is a schematic view of a variable configuration annular multi-electrode pulsed electric field ablation catheter in accordance with example 1 of the present invention;

FIG. 15 is a schematic view of the distal end of a variable configuration annular multi-electrode pulsed electric field ablation catheter (with a guidewire) in accordance with example 1 of the present invention;

fig. 16 is an example of ablation point marking of the cardiac electrophysiology three-dimensional mapping system in embodiment 1 of the present invention.

Detailed Description

The present invention will be described in further detail with reference to test examples and specific embodiments. It should be understood that the scope of the above-described subject matter is not limited to the following examples, and any techniques implemented based on the disclosure of the present invention are within the scope of the present invention.

Example 1

A block diagram of an intelligent pulsed electric field ablation system with controlled output channels and the implementation principle are shown in fig. 1-2. A multi-electrode pulsed electric field ablation catheter that can be used with this system is shown in fig. 9-15. The following is a detailed implementation.

1. The impedance of the multi-electrode pulsed electric field ablation catheter in a blood pool is different from the impedance of the catheter in contact with tissues, and meanwhile, the change of the contact degree of the catheter in the moving process can have a certain reaction on the change rate of the impedance. Therefore, whether the tissue is attached to the tissue currently can be judged through the impedance between the electrodes, and the tissue attachment degree is reflected through the change rate of the impedance.

2. When the tissue is discharged by the pulse electric field, irreversible electroporation is generated, and programmed cell death is caused. These may reflect a decrease in impedance value, a change in PH, a change in dielectric constant, etc. to the ablation site. However, when the pulsed electric field is ablated to a certain extent, these changes will be relatively slow, reaching a certain balance, because now the cardiomyocytes that can cause irreversible electroporation at this field strength have been treated, and it is not meaningful to continue the ablation. Therefore, the impedance value change condition, the pH value change, the dielectric constant change and the like of the current ablation position can be detected in real time after each ablation, and whether the pulsed electric field ablation is needed at the current point position or not can be judged.

3. In order to avoid the influence of the pulsed electric field ablation on the conducting cells of important tissues (such as the sinoatrial node, the his bundle and the like), the electrophysiological signals around the electrodes need to be effectively identified, and the electrodes with risks identified by the electrophysiological signals around the electrodes need to be prevented from being discharged.

4. The impedance detection can be performed in the following ways, i.e., time-division switching detection, fusion extraction detection, and frequency-division switching detection. The detection signal is usually loaded at a frequency of 2Khz to 200Khz, and the electrical signal obtained by the extraction is converted into an actual impedance signal through filtering, as shown in fig. 3 to 6. The electrode is considered to be attached to the tissue when the impedance value is 150 ohms, and after the high-voltage pulse ablation is carried out, the ablation is carried out for ten times, the impedance value is reduced by 40-50 ohms, which indicates that the ablation is an effective ablation point. When the electrode is in a blood pool, the impedance is 100 ohms, but when the electrode is attached to human tissues, the impedance value is 200 ohms, the attachment state is reflected by the impedance value, and the attachment state is also reflected by the impedance change rate.

5. PH sensor is usually adopted in PH detection, and the PH values of the areas corresponding to different electrodes are detected in a time-sharing loading manner through channel switching, for example, the PH value is stable within the range of +/-0.5, which indicates that perforation is finished without ablation, in addition, the detected NA ion concentration is high, the PH value is higher, after cell perforation, potassium ions in cells overflow out, the PH value is reduced, which indicates that the system has been perforated through the wall, and ablation is completed, which is an effective ablation point.

6. The detection of the dielectric constant utilizes sinusoidal excitation signals with a plurality of frequencies in the range of 5KHz-300MHz to excite the change of complex impedance electric signals corresponding to the reaction cell tissues under different frequency signals. And these signals are converted into signals in the frequency domain by fourier transform or the like. The frequency domain signal of different types of cells and even ions under a certain frequency can be obtained, and the frequency domain signal is a characteristic value capable of reflecting the change of the frequency domain signal, and the value is used as the basis for determining the dielectric constant. The change of the cell tissue in the area after the pulsed electric field ablation can be reflected to a certain extent through the change of several parameters such as the dielectric constant of the myocardial cells, NA ions, CA ions and K ions.

Further, the impedance detection includes detection of an impedance value and detection of a rate of change of impedance,

when the impedance value is in the first impedance threshold range and the impedance change rate is in the first change rate range, the electrode outputting the high-voltage pulse is in the blood pool and is not attached to the human tissue. The first impedance threshold range is 100-150 ohms; the first range of rates of change of impedance is a rate of change of impedance much greater than 50 ohms/0.5 seconds.

And when the impedance value is in a second impedance threshold range and the impedance change rate is in a second change rate range, the electrode outputting the high-voltage pulse is attached to the human tissue. The second impedance threshold range of impedance values is about 200 ohms and the second rate of change of impedance rate range is about 50 ohms/0.5 seconds.

Further, on the premise that the electrode outputting the high-voltage pulse is attached to the human tissue, if the variation range of the PH detection result is within a range of ± 0.5, it can be determined that the ablation state is perforation only by using the PH detection result.

Further, on the premise that the electrode outputting the high voltage pulse is attached to the human tissue, if the result of the permittivity detection is within a preset permittivity range (for example, the K-ion permittivity is 100), the ablation state is perforation.

In addition, on the premise that the electrode outputting the high-voltage pulse is not attached to the human tissue, the change range of the result of the PH detection is within the range of ± 0.5, and the result of the permittivity detection is within the preset permittivity range, so that the ablation state can be judged to be perforation.

7. The electrophysiological signals are mainly acquired through a band-pass filtering acquisition circuit and judged and identified through an algorithm.

7.1 the specific intelligent output channel control is based on the description of FIGS. 1-3. The pulsed electric field ablatograph has the functions of impedance detection, PH detection and dielectric constant detection, and the identification of electrophysiological signals is realized by establishing the consumable catheter and a cardiac electrophysiological three-dimensional mapping system through the pulsed electric field ablatograph.

7.2 the pulse electric field ablation instrument judges the current impedance condition through impedance detection, and whether the current position of the electrode is a blood pool or not is identified according to the current impedance condition. And if so, the electrode will not discharge. It is ensured that no meaningless discharge will occur against the blood pool.

7.3 pulse electric field ablation appearance can discern the change rate of current electrode impedance through impedance detection, when the change rate appears great change or great fluctuation of making a round trip, can judge current electrode paste to be unstable even paste the degree and descend with this, the electrode here should not discharge at this moment to avoid reducing the effect of discharging. The pulse electric field ablation instrument can not be started until the position is judged to be well attached through impedance detection by operating the catheter.

The 7.4 pulsed electric field ablation instrument can also judge the characteristic of the current electrode ablation impedance after each discharge through means of impedance detection, PH detection, dielectric constant detection and the like. When the above parameters are combined, and when the change rate and fluctuation of the impedance value, the pH value and the dielectric constant tend to be stable, the region where the current electrode is located is considered to be free from ablation. The pulsed electric field energy ablatograph can disconnect the electrode passage according to the result and does not ablate any more until the catheter moves to other areas, and the pulsed electric field energy ablatograph can lead the energy output function of the electrode passage.

7.5 the electrophysiological signal monitoring of the multi-electrode catheter can be carried out through a channel established by the multi-electrode ablation catheter and the cardiac electrophysiological three-dimensional mapping system through the pulsed electric field ablation instrument. When the three-dimensional mapping system of the cardiac electrophysiology identifies that the electrophysiology signals on certain electrode paths are key conduction signals, such as sinus node, atrioventricular node or his bundle. The cardiac electrophysiology three-dimensional mapping system is timely transmitted to the pulsed electric field ablation instrument through the communication bus, and the pulsed electric field ablation instrument disconnects an electrode passage which needs to be protected and is determined according to the cardiac electrophysiology three-dimensional mapping system, so that energy output cannot pass through the electrode passage, and ablation safety is effectively guaranteed.

7.6 the pulse electric field ablation instrument intelligently switches the electrode path according to the information in the ablation process, thereby ensuring that the electrode path is effectively attached to and ablated at the position needing to be continuously treated. In the process, the pulsed electric field ablator transmits the information of the enabled electrode path to the cardiac electrophysiology three-dimensional mapping system in real time. The cardiac electrophysiology three-dimensional mapping system can mark the actual discharge point on the ablation model according to the information. The discharge point marked by the method can indicate a practical and effective ablation point, so that an operator can judge whether the ablation area meets the requirements according to the discharge point, and a patient can be treated more effectively.

While there have been shown and described what are at present considered the fundamental principles and essential features of the invention and its advantages, it will be apparent to those skilled in the art that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present description refers to embodiments, the embodiments do not include only one independent technical solution, and such description is only for clarity, and those skilled in the art should take the description as a whole, and the technical solutions in the embodiments may be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. An intelligent pulsed electric field ablation system for controlling an output channel is characterized by comprising a pulsed electric field ablation instrument and a multi-electrode pulsed ablation catheter,

2. The system of claim 1, wherein the ablation state comprises unperforated and perforated, and wherein the channel outputting the high voltage pulse is closed when the ablation state is perforated and remains open when the ablation state is unperforated.

3. An intelligent output channel-controlled pulsed electric field ablation system as in claim 1, wherein said impedance detection includes detection of an impedance value and detection of a rate of change of impedance,

4. The system of claim 3, wherein the impedance signal for the impedance detection is obtained by: and loading signals with the frequency of 2KHz to 200KHz to the electrode of the multi-electrode pulse ablation catheter, collecting return signals of the signals from 2KHz to 200KHz acting on the electrode, and converting the return signals into impedance signals through filtering treatment.

5. The system as claimed in claim 3, wherein the ablation state is perforation if the variation of the PH value detected by the PH value detection is ± 0.5, under the condition that the electrode outputting the high voltage pulse is attached to the human tissue.

6. The system as claimed in claim 3, wherein the ablation state is perforation if the result of the permittivity detection is within a predetermined permittivity range under the condition that the electrode outputting the high voltage pulse is attached to the human tissue.

7. The system of claim 6, wherein the permittivity signal for permittivity detection is obtained by:

8. The system as claimed in claim 3, wherein the ablation status is perforation if the PH value detected by the PH sensor is within ± 0.5 and the permittivity detected by the permittivity sensor is within the predetermined permittivity range, without the electrode outputting the high voltage pulse contacting the tissue.

9. The system of claim 1, wherein the ablation state is perforation if the rate of change of impedance, the rate of change of PH, and the rate of change of permittivity are stable.

10. The system of any one of claims 1-9, further comprising a cardiac electrophysiology three-dimensional mapping system,

the cardiac electrophysiology three-dimensional mapping system is also used for detecting key conducting signals from a sinoatrial node, an atrioventricular node or a his bundle and outputting the key conducting signals to the pulsed electric field ablator; and the pulsed electric field ablator cuts off the channel of the high-voltage pulse signal related to the key conduction signal.