CN116058952A - Open monopole pulse electric field ablation instrument - Google Patents

Abstract

The invention provides an open type monopole pulse electric field ablation instrument, which comprises a heart absolute refractory period monitoring module, a heart absolute refractory period monitoring module and a control module, wherein the heart absolute refractory period monitoring module responds to real-time monitoring of the heart absolute refractory period and generates a corresponding absolute refractory period triggering signal; the pulse energy triggering module is used for generating a pulse energy triggering signal; the pulse electric field energy generator responds to the pulse energy trigger signal and controls the transmission of the pulse electric field by utilizing a preset energy generation trigger algorithm; and the energy separation module is externally connected with the ablation catheter and is used for outputting pulse energy from the ablation catheter to heart focus tissues for ablation treatment, wherein the pulse energy returns to the electrotome negative plate externally connected with the pulse energy triggering module through a human body, so that reflux is realized. The invention is upgraded from the traditional radio frequency ablation to the dual-mode of the pulse electric field selective ablation and the radio frequency ablation, improves the operation safety, and does not generate transmural injury to esophagus, phrenic nerve and pulmonary vein organs compared with the radio frequency ablation.

Description

Open monopole pulse electric field ablation instrument

Technical Field

The invention relates to the technical field of clinical medical instrument manufacturing, in particular to an open type monopole pulse electric field ablation instrument.

Background

The normal sinus rhythm of the heart begins with the sinoatrial node, which produces depolarizations that depolarize myocardial tissue cells, depolarize adjacent myocardial tissue cells, effecting trans-atrial propagation of the depolarization, whereby the atria contract and empty blood from the atria into the ventricles, and electrophysiological signals are then delivered to the myocardial tissue cells of the ventricles via the atrioventricular node and the his bundle. The depolarization of the cells propagates across the ventricles, causing the ventricles to contract, and the conduction system effects an organized sequence of myocardial contractions, resulting in a regular heartbeat.

The uneven distribution of refractoriness of certain parts of the cardiomyocytes in the heart may lead to abnormal conduction paths in the heart tissue, possibly resulting in wavelets of the electrocardiosignal circulating around certain tissues. Abnormal conduction pathways cause abnormal, irregular and potentially fatal arrhythmias. Arrhythmia may occur in the atria, such as in the form of atrial tachycardia, atrial fibrillation, or atrial flutter. Arrhythmia may also occur in the ventricles, such as in the form of ventricular tachycardia or high lethality ventricular fibrillation.

Methods of treating cardiac arrhythmias include fabricating one or more lesions on the myocardium that divide individual linear lesions in the endocardium, disabling the formation of abnormal conduction pathways. The method for manufacturing the lesion can be to apply radio frequency energy thermal ablation or cryogenically cool myocardial cells at the target site, but has the potential disadvantage of damaging non-target tissues such as esophagus or phrenic nerve at the same time, causing complications.

Pulse catheter ablation is a common surgical treatment method, which uses high-voltage pulse electric field energy above 2000V to instantaneously discharge at high frequency through an electrode to form irreversible micropores on a cell membrane, so that the change of the permeability of the cell membrane is caused, the homeostasis in the cell is destroyed, and the apoptosis is caused, thereby achieving the purpose of treatment. However, the existing pulse ablation generally needs to design a brand new pulse ablation catheter, and special insulation treatment is needed for the electrode wire to ensure the transmission of high-voltage pulses, meanwhile, arc effect between adjacent electrodes is avoided, and the pulse ablation catheter is completed by combining a pulse energy source. Clinically, the method requires a brand new operation mode and long-time clinical training. Meanwhile, the original three-dimensional mapping platform and the radio frequency ablation catheter are required to be redesigned, a low-frequency low-voltage three-dimensional mapping system and a high-voltage high-frequency pulse electric field are effectively isolated, and development cost is high.

Disclosure of Invention

Aiming at the technical problems of the prior art that the radio frequency ablation safety is poor, transmural injury can be generated to esophagus, phrenic nerve and pulmonary vein organs. In view of this, the present invention provides an open monopole pulsed electric field ablator.

The technical scheme adopted by the invention is that the open type monopole pulse electric field ablation instrument comprises:

the heart absolute refractory period monitoring module responds to the heart absolute refractory period monitored in real time and generates a corresponding absolute refractory period trigger signal;

the pulse energy triggering module is used for generating a pulse energy triggering signal corresponding to the absolute refractory period triggering signal;

the pulse electric field energy generator is connected with the pulse energy triggering module and responds to the pulse energy triggering signal to control the transmission of the pulse electric field by utilizing a preset energy generation triggering algorithm;

the energy separation module is externally connected with an ablation catheter and is used for outputting pulse energy of the pulse electric field to heart focus tissues for ablation treatment through the ablation catheter, wherein the pulse energy returns to an electrotome negative plate externally connected with the pulse energy triggering module through a human body, and backflow is achieved.

In one embodiment, the open monopolar pulsed electric field ablation instrument further comprises:

the intra-cavity electrode impedance detection module is used for controlling the pulse energy to be output to heart focus tissues by the ablation catheter within a preset impedance range;

and, open monopole pulsed electric field ablation appearance still has externally:

the three-dimensional mapping system is connected with the energy separation module and is used for three-dimensional modeling of heart focus;

the multi-conductor body surface electrode is connected with the heart absolute refractory period monitoring module and is used for monitoring body surface ECG signals, wherein the body surface ECG signals comprise electrophysiological signals representing the heart absolute refractory period;

and the multi-guide physiological instrument is connected with the energy separation module and is used for monitoring electrophysiological signals in the heart cavity.

In one embodiment, the ablation catheter is used for at least one of pulsed energy ablation or radio frequency ablation.

In one embodiment, a tip electrode and a ring electrode inside the ablation catheter are connected across an external resistance such that a voltage difference between the tip electrode and the ring electrode is less than a safety threshold.

In one embodiment, the energy separation module comprises:

the three-dimensional mapping and pressure sensing connector is connected with the three-dimensional mapping system;

the electrode comprises a large-head electrode and an annular electrode;

the three-dimensional mapping and pressure sensing connector, the connector for connecting the multi-conductivity physiological instrument and the intracavity electrode impedance detection module are connected with the large-head electrode and the annular electrode through signal wires, and relay switches are respectively arranged on the connected signal wires.

In one embodiment, the pulsed electric field energy generator generates a DC voltage in the range of 1900 volts to 3000 volts, with adjustable 100, 200, 500 volt spacing.

In one embodiment, the discharging mode of the pulse electric field energy generator comprises: at least one of a monopolar monophasic mode or a monopolar biphasic mode.

In one embodiment, the unipolar single-phase mode includes:

at least two pulses form a pulse burst, a burst interval is interposed between adjacent ones of said pulse bursts, and only the normal phase pulse burst.

In one embodiment, the monopolar biphasic mode comprises:

at least two pulses form a pulse group, a pulse group interval is inserted between two adjacent pulse groups, and the pulse group interval comprises a positive phase pulse train and a negative phase pulse train, and a delay is set between positive and negative voltages.

In one embodiment, the pulsed electric field energy generator further comprises a discharge protection module for preventing an electric leakage condition of the pulsed electric field energy generator.

By adopting the technical scheme, the invention has at least the following advantages:

the open type monopole pulse electric field ablation instrument provided by the invention is upgraded from the traditional radio frequency ablation to a pulse electric field selective ablation and radio frequency ablation dual-mode, so that the operation safety is improved, and compared with the radio frequency ablation, the open type monopole pulse electric field ablation instrument can not generate transmural damage to esophagus, phrenic nerve and pulmonary vein organs.

Drawings

FIG. 1 is a block diagram of the internal modules of an open monopole pulsed electric field ablator according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of four-lead cardiac absolute refractory period monitoring in accordance with an embodiment of the present invention;

FIG. 3 is a schematic diagram of a discharge time period of a proposed releasable pulse energy in accordance with an embodiment of the present invention;

FIG. 4 is a schematic diagram illustrating the conduction between high voltage electrodes of a pulsed electric field according to an embodiment of the present invention;

FIG. 5 is a block diagram of an energy separation module architecture according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of a high frequency high voltage pulsed electric field generation module according to an embodiment of the present invention;

FIG. 7 is a schematic diagram of a unipolar monophasic pulsed electric field parameter setting according to an embodiment of the present invention;

FIG. 8 is a diagram of a unipolar biphasic asymmetric pulsed electric field parameter setup according to an embodiment of the present invention;

FIG. 9 is a timing diagram of high voltage high frequency pulses according to an embodiment of the present invention;

fig. 10 is a schematic diagram of a pulsed electric field discharge protection module according to an embodiment of the present invention.

Detailed Description

In order to further describe the technical means and effects adopted by the present invention for achieving the intended purpose, the following detailed description of the present invention is given with reference to the accompanying drawings and preferred embodiments.

In the drawings, the thickness, size and shape of the object have been slightly exaggerated for convenience of explanation. The figures are merely examples and are not drawn to scale.

It will be further understood that the terms "comprises," "comprising," "includes," "including," "having," "containing," and/or "including," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. Furthermore, when a statement such as "at least one of the following" appears after a list of features that are listed, the entire listed feature is modified instead of modifying a separate element in the list. Furthermore, when describing embodiments of the present application, the use of "may" means "one or more embodiments of the present application. Also, the term "exemplary" is intended to refer to an example or illustration.

As used herein, the terms "substantially," "about," and the like are used as terms of a table approximation, not as terms of a table level, and are intended to illustrate inherent deviations in measured or calculated values that would be recognized by one of ordinary skill in the art.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

It should be noted that, in the case of no conflict, the embodiments and features in the embodiments may be combined with each other. The present application will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.

The apparatus is an open pulse energy system for use in conjunction with cardiac interventional ablation catheters for delivering pulsed electric field energy to heart focal tissue that causes irreversible electroporation of cardiomyocytes. The traditional radio frequency ablation catheter is directly connected with the three-dimensional mapping system, and is connected with a radio frequency ablation instrument and a saline infusion pump through the three-dimensional mapping, so that radio frequency ablation is completed. As shown in the figure, the radio frequency ablation catheter is not directly connected with the electrophysiology three-dimensional mapping system any more, in the system, the three-dimensional mapping system for clinical use and the radio frequency ablation catheter are respectively connected into a PFA (pulse electric field ablation, pulsed field ablation) ablation instrument device through customized special lines, the upgrading from radio frequency ablation to PFA ablation is completed, the original radio frequency ablation instrument does not need to be removed from the system, and an operator can freely select radio frequency ablation or pulse ablation.

In a first embodiment of the present invention, an open monopole pulsed electric field ablation apparatus, as shown in fig. 1, comprises:

the heart absolute refractory period monitoring module responds to the heart absolute refractory period monitored in real time and generates a corresponding absolute refractory period trigger signal;

the pulse energy triggering module is used for generating a pulse energy triggering signal corresponding to the absolute refractory period triggering signal;

the pulse electric field energy generator is connected with the pulse energy triggering module and responds to the pulse energy triggering signal to control the transmission of the pulse electric field by utilizing a preset energy generation triggering algorithm;

the energy separation module is externally connected with an ablation catheter and is used for outputting pulse energy of the pulse electric field to heart focus tissues for ablation treatment through the ablation catheter, wherein the pulse energy returns to an electrotome negative plate externally connected with the pulse energy triggering module through a human body, and backflow is achieved.

In this embodiment, the open monopole pulsed electric field ablator further includes:

the intra-cavity electrode impedance detection module is used for controlling the pulse energy to be output to heart focus tissues by the ablation catheter within a preset impedance range;

further, in this embodiment, the open monopole pulsed electric field ablation apparatus is further externally connected with:

the multi-conductor body surface electrode is connected with the heart absolute refractory period monitoring module and is used for monitoring body surface ECG signals, wherein the body surface ECG signals comprise electrophysiological signals representing the heart absolute refractory period;

and the multi-guide physiological instrument is connected with the energy separation module and is used for monitoring electrophysiological signals in the heart cavity.

In this embodiment, the ablation catheter is used for at least one of pulsed energy ablation or radio frequency ablation.

In this embodiment, the tip electrode and the ring electrode inside the ablation catheter are connected across the external resistor, so that the voltage difference between the tip electrode and the ring electrode is smaller than a safety threshold.

In this embodiment, the energy separation module includes: the three-dimensional mapping and pressure sensing connector is connected with the three-dimensional mapping system; the electrode comprises a large-head electrode and an annular electrode;

the three-dimensional mapping and pressure sensing connector, the connector for connecting the multi-conductivity physiological instrument and the intracavity electrode impedance detection module are connected with the large-head electrode and the annular electrode through signal wires, and relay switches are respectively arranged on the connected signal wires.

In this embodiment, the dc voltage generated by the pulse electric field energy generator ranges from 1900 volts to 3000 volts, and the pitches of 100, 200, and 500 volts are adjustable.

In this embodiment, the discharging mode of the pulse electric field energy generator includes: at least one of a monopolar monophasic mode or a monopolar biphasic mode.

Specifically, the monopolar single-phase mode includes:

at least two pulses form a pulse burst, a burst interval is interposed between adjacent ones of said pulse bursts, and only the normal phase pulse burst.

Specifically, the monopolar biphasic mode comprises:

at least two pulses form a pulse group, a pulse group interval is inserted between two adjacent pulse groups, and the pulse group interval comprises a positive phase pulse train and a negative phase pulse train, and a delay is set between positive and negative voltages.

In one embodiment, the pulsed electric field energy generator further comprises a discharge protection module for preventing an electric leakage condition of the pulsed electric field energy generator.

Compared with the prior art, the embodiment has at least the following advantages:

1) The traditional radio frequency ablation is upgraded to a dual-mode of pulse electric field selective ablation and radio frequency ablation, so that the operation safety is improved, and compared with the radio frequency ablation, the transmural injury to esophagus, phrenic nerve and pulmonary vein organs is avoided;

2) The system can be compatible with a radio frequency ablation catheter, an annular mapping catheter and a three-dimensional mapping system for clinical use, and allows a doctor to perform an operation according to radio frequency ablation operation, so that training time, workflow adjustment and cost are saved. Seamless upgrading of the radio frequency ablation system is realized;

3) The radio frequency ablation is reserved on the basis of pulse ablation, so that a dual-mode ablation mode is realized, and switching operation can be performed between the radio frequency ablation and the pulse ablation;

4) According to the tissue depth of the focus, a plurality of ablation modes with different pulse electric field energy can be set to ablate arrhythmia focuses with different tissue depths;

5) Impedance measurement can be automatically carried out in the ablation process, and ablation energy is adjusted to achieve safe transmural injury;

6) The pulse energy delivery algorithm keeps the energy output in a balanced way under different concentricity, so that an ideal ablation effect is achieved;

7) Is compatible with the existing multi-guide physiological instrument in the catheter chamber cavity, and realizes the intra-operation electrophysiological monitoring.

The second embodiment of the present invention, corresponding to the first embodiment, introduces an open monopole pulsed electric field ablator.

Referring to fig. 1, the open monopole pulsed electric field ablator is externally connected with the following devices:

1) The electrophysiology three-dimensional mapping system is used for completing heart three-dimensional modeling;

2) The monopolar pressure-sensing saline perfusion radio frequency ablation catheter can be compatible with pulsed electric field ablation and radio frequency ablation simultaneously;

3) A body surface multi-lead electrode for collecting body surface ECG signals;

4) A multi-guide physiological instrument for monitoring an intra-cavity electrophysiological signal;

5) The electrotome negative plate and the monopole ablation catheter form a discharge loop.

The inside of the open type monopole pulse electric field ablation instrument consists of 5 core modules: 1) a high-frequency high-voltage pulse electric field energy generator, 2) a pulse energy triggering module, 3) a heart absolute refractory period monitoring module, 4) an energy separation and system switching module and 5) an intra-cavity electrode impedance detection module.

The high-frequency high-voltage pulse electric field energy generator is internally connected with the pulse energy triggering module, and the transmission of the high-voltage pulse electric field is controlled through an energy generation triggering algorithm.

The pulse energy triggering module is externally connected with an electrotome negative plate and a foot pedal switch, monitors the cardiac cycle of the cardiac refractory period triggering signal, and sends the triggering signal based on a proper impedance value interval in a proper cardiac cycle.

The heart absolute refractory period real-time detection module is externally connected with a tetrad body surface electrode, monitors body surface ECG signals in real time, monitors and analyzes the heart absolute refractory period, and generates a trigger signal.

The energy separation and system switching module is externally connected with a multi-guide physiological instrument, a three-dimensional mapping system and a monopole ablation catheter. The energy separation module is used for isolating the high-frequency high-voltage pulse electric field, so that the system can be compatible with an electrophysiology three-dimensional mapping system of the existing catheter chamber, a multi-guide physiology instrument and a traditional large-head electrode radio-frequency ablation pressure-sensing saline perfusion catheter.

And the intra-cavity electrode impedance detection module ensures that the pulse electric field is transmitted within a reasonable impedance range. Pulse energy generated by a high-frequency high-voltage pulse electric field energy generator is transmitted to an energy separation module, and the pulse energy is output to heart focus tissues for ablation by an ablation catheter through the energy separation module, and passes through a human body to return to a negative plate of the electrotome to form a loop.

The invention adopts a monopolar pulse ablation mode, current enters the tissue from the head end of an ablation catheter and flows to a return electrode (a body surface negative plate) at the distal end, so that ablation energy extends to myocardial tissue to reach deeper treatment depth. This is in contrast to multipole pulsed electric field electrodes, which are relatively close in distance, at the surface of the same myocardial tissue, so that the pulsed energy transmitted by the multipole electrodes can only enter the tissue shallowly, only back to the end effector with the return electrode, so that the energy does not propagate so deeply, the current will follow the path of least resistance, which is directed to the surface tissue, without too much current going deep into the tissue.

Thus, for multipole electrode arrangements, a more stringent treatment regime is required to achieve a deeper treatment depth in the target tissue. This feature appears more pronounced as the target depth increases further (i.e., from 2mm to 4mm may require about 4 times the energy, while expanding the treatment depth from 2mm to 6mm may require about 16 times the energy, some multipole designs require up to 100 joules to achieve the same lesion depth depending on the electrode configuration, and often involve various negative effects such as regional tissue overheating.

The vascular gas embolism is a focus of many pulsed electric field treatments, clinical studies show that only 0.1 milliliter of air in coronary arteries can cause myocardial injury, the system reduces the generation of micro bubbles by using a biphasic pulse wave mode, simultaneously, the saline hole at the head end of a catheter is ablated by radio frequency, saline is infused into the surface of the electrode at the head end of the catheter, the generation of micro bubbles is further reduced, and a series of complications are avoided. The saline injection flow rate is designed to be more than 4 ml/min.

The system sub-module in this embodiment will be described in detail below.

1) A cardiac absolute refractory period monitoring module;

the heart absolute refractory period real-time detection module is an important system safety component module and is used for providing a gating signal for an ablation energy source. The invention provides real-time monitoring of the absolute refractory period of a heart based on a body surface QRS, which is externally connected with four lead electrodes on the body surface, transmits an R wave trigger signal and provides refractory period trigger synchronous pulses to an energy transmitter. Since the vulnerable period of cardiomyocytes is very sensitive to the applied electric field energy, any applied pulse that reaches the threshold of fibrillation can easily induce fatal ventricular fibrillation, resulting in sudden death. Therefore, the invention is also provided with a real-time detection module for the absolute refractory period of the heart, and only pulse electric fields are allowed to be issued in the absolute refractory period of the myocardial cells, so that the heart ventricular fibrillation is avoided.

As shown in fig. 2, the QRS absolute refractory period determination condition is the onset of R wave, and the length is: 80% QTc-80ms (wherein QTc=QT/(RR≡0.5) (ms), RR interval is QT interval at 1 second) with a regulation pitch of 5%. The four-lead trigger electrode may be set to any RA, LA, RL, LL lead selection. The Notch filter is built in, the triggering delay is smaller than 2ms, the monitoring precision error of the R-R wave is smaller than 75us, and the R wave triggering pulse is output.

The absolute refractory period is realized through the gating of the body surface limb lead QRS wave, and the gating conditions of the body surface four lead QRS wave are as follows: 1) dominant wave upward, 2) forward absolute amplitude above 5mv, 3) baseline drift less than 10%, 4) no clutter interference, 5) continuous stabilization above 3 QRS waves, 6) effective identification of the starting and stopping points of QRS waves and T waves, and 7) compliance with the other gating parameter conditions.

Fig. 3 is a schematic diagram of a discharge time period for which pulse energy is recommended to be released, and at RT, the discharge time period is recommended, and the pulse energy is not released to cause ventricular fibrillation. As shown in fig. 3, the time that the discharge can be actually performed is in ST segment, i.e. 1-100ms after the R-wave peak is triggered, and the ST segment can last a discharge window. Meanwhile, R wave synchronous signals need to be continuously monitored, and discharge is started after 3-5 continuous R wave top trigger signals are arranged, so that the patient is prevented from being subjected to ventricular fibrillation caused by discharge in a T section.

2. ) Ablation catheter and three-dimensional mapping system connection and energy separation module

The pulse energy output designed by the invention is connected into a loop through the head end electrode of the large-head catheter and the negative plate of the body surface, and adopts a monopole pulse electric field ablation mode. The ablation catheter and the three-dimensional mapping system connection and energy separation module are used for being compatible with the electrophysiology three-dimensional mapping system of the existing catheter room, the multi-guide physiology instrument and the traditional large-head electrode radio-frequency ablation pressure-sensing saline perfusion catheter. Meanwhile, the separation module provides an important pulse energy separation function, separates pulse electric field energy output from the multi-conductivity physiological recorder and the three-dimensional mapping system, prevents high-voltage signals from interfering low-voltage signal processing equipment, and solves the problems of electric arc and short circuit caused by high-voltage series connection effect among a plurality of electrodes.

Since conventional rf ablation catheters are designed for lower voltages and have not only a distal tip electrode but also a plurality of ring electrodes near the tip of the conventional rf ablation catheter, each electrode having a respective connecting lead extending through the catheter to the proximal end of the catheter, which leads are contained within the catheter body, the conventional rf ablation catheters are designed for lower voltages and are therefore not designed to be highly insulated from each other, which insulation is insufficient to insulate voltage differences exceeding about 1500V, if pulse energy is outputted directly through the tip electrode, a high energy high frequency pulse signal is required to be outputted during a pulse ablation procedure, and the distance between the tip electrode and the ring electrode is close, a voltage difference exceeding 1500V is generated between the tip electrode and the ring electrode, and arcing and shorting between the connecting leads within the catheter is easily generated, so that conventional rf ablation catheters cannot be directly applied to pulse ablation.

As shown in fig. 4, a high-voltage high-frequency pulse is output at the large-head electrode, because blood in the heart chamber is a conductor, the annular electrode simultaneously induces an environmental voltage, so that the cross-boundary voltage difference between the head-end electrode and the annular electrode is larger than the insulation voltage threshold of the radio-frequency ablation catheter, and the breakdown and short circuit of an insulator between the head-end electrode and the annular electrode lead are caused. In order to prevent electric arc and short circuit between electrodes, the invention reduces the crossover voltage by bridging the resistor so that the voltage difference is in a safe range. The voltage difference between the big-end electrode and the annular electrode is controlled by adjusting the resistance value of the bridging resistor, so that the voltage difference is not higher than the voltage threshold value in the insulation state of the traditional radio frequency ablation catheter, and the radio frequency ablation catheter is prevented from generating electric arcs and short circuits.

The internal design of the energy separation module of the invention is shown in fig. 5:

the invention comprises a three-dimensional mapping and pressure sensing connector which is used for being directly connected with an electrophysiological three-dimensional mapping system, and a clinical radio frequency ablation catheter can be directly connected with a compatible electrophysiological three-dimensional mapping system to realize three-dimensional electrophysiological modeling and pressure monitoring. Meanwhile, the large-head electrode and other annular electrodes are separated from other signal wires, as shown in fig. 5, the three-dimensional mapping and pressure sensing connector, the connector for connecting the multi-guide physiological instrument and the impedance measuring module are connected with the large-head electrode and the annular electrodes through the signal wires, relay switches are respectively arranged on the connected signal wires, when high-voltage high-frequency pulse signals are output, the digital relay can disconnect the connection of the large-head electrode and the annular electrodes with the multi-guide physiological instrument, the three-dimensional mapping instrument and the intra-cavity electrode impedance measuring module, the high-voltage signals are ensured not to influence the monitoring of peripheral equipment and the impedance measurement, the disconnection duration is short, and the signal influence on the electrophysiological three-dimensional mapping system, the multi-guide physiological instrument and the intra-cavity electrode impedance measuring module is reduced to the minimum.

And when the high-frequency high-voltage pulse signals are stopped to be output, the relays between the high-frequency high-voltage pulse energy electrode interfaces and the large-head electrodes and the annular electrode signal lines are disconnected, the high-frequency high-voltage pulse energy is stopped to be input, relay switches of the large-head electrodes, the annular electrodes, the multi-conductivity physiological instrument, the three-dimensional mapping instrument and the intra-cavity electrode impedance monitoring module are controlled to be closed again, and the multi-conductivity physiological instrument, the three-dimensional mapping instrument and the intra-cavity electrode impedance monitoring module are restored to work again.

The three-dimensional position signal line, the position sensing signal line and the temperature sensing signal line are connected with the corresponding sensor at the head end of the catheter in a straight-through mode, and no additional relay is needed to be connected.

The large-head electrode and the annular electrode form an electrode pair, the electrode pair is output to the intracavity electrode impedance measurement module, impedance monitoring between the large-head electrode and the annular electrode is carried out, the real-time impedance monitoring can be disconnected in the pulse electric field ablation process, and the influence of a high-voltage signal on an impedance measurement result is prevented, so that the test result is inaccurate.

The large-head electrode is separated singly, the monopole pulse energy designed by the system is output through the large-head electrode at the head end of the ablation catheter, and is connected with the electrotome negative plate on the body surface to form a loop, and the annular electrode of the ablation catheter is only used for connecting a multi-guide physiological instrument to record and stimulate electrophysiological signals in a cavity.

3) Pulse electric field energy generator

The high-voltage high-frequency pulse electric field generating module mainly comprises a high-voltage generator and a program pulse controller. The high voltage generator can generate a direct current high voltage in a range from 1900 volts to 3000 volts, the distance between 100 volts, 200 volts and 500 volts is adjustable, the program pulse controller is responsible for generating default instruction pulses and adjusting instruction pulses, corresponding ablation depth can be generated under corresponding specific energy, when atrial fibrillation ablation is carried out, the ablation depth of the pulmonary pulse isthmus needs to reach 10mm, and the pulse ablation depth is controlled by adjusting the energy generated by a pulse electric field. The pulmonary vein isthmus can reach proper ablation depth, and recurrence is prevented.

The high voltage high frequency pulsed electric field transmission module is shown in fig. 6:

the module is controlled by an external start trigger signal. The module includes a central control system, and energy charging memory, high voltage frequency converter, and delay controller. When the external starting trigger signal is received, the energy transmission is started after 0-100 ms delay through a delay controller, so that the pulse energy is ensured to be output in the refractory period of the heart, and the pulse energy is ended at the front of the T wave, so that the occurrence of ventricular fibrillation is prevented. The central control system is connected with the UI user interface energy selection input interface to complete the configuration of each pulse electric field parameter.

The energy storage and the high-voltage high-frequency converter are classified into low energy, medium energy, high energy and ultra-high energy by the UI user interface, so that the ablation depth reaches 1 mm-10 mm, and the ablation energy is accurately controlled by selecting proper voltage and frequency to generate pulse signal strings according to the tissue depth to be ablated. The energy charging storage accomplishes the energy storage by a large capacitor.

The system is designed to use a unipolar pulsed electric field. The unipolar pulse discharge mode is divided into two types: 1) Unipolar monophasic mode, 2) unipolar biphasic mode, wherein in monophasic mode the pulses are only positive phase, the others all belong to biphasic, biphasic mode can be divided into completely symmetrical or asymmetrical discharge modes.

1. Single-pole single-phase pulse electric field

As shown in fig. 7, which shows a waveform of unipolar monophasic pulse PEF (peak expiratory flow ), two or more pulses form a pulse group (Packet), a pulse group interval rest time is inserted between the packets, and the monophasic pulse has only a normal phase pulse train; the core parameters of the PEF pulsed electric field include:

pulse width of 1-10us, corresponding to pulse frequency of 1000KHz-100KHz

The pulse interval is an important parameter, and the pulse interval of the system is 100us-20ms.

The pulse group interval is 100us-10000us, and the proper pulse group interval is set for reducing the pain feeling of patients.

The number of pulses in the pulse group is used for transmitting energy and determining the final ablation depth, the number of pulses in the pulse group of the system is between 10 and 200, and an operator sets pulse number parameters in the pulse group on a UI interface according to the ablation depth required by a target ablation part to accurately control the ablation depth.

2. Unipolar biphasic pulsed electric field

FIG. 8 is a schematic diagram of a unipolar biphasic pulsed electric field waveform, where biphasic PEF increases two parameters compared to monophasic pulsed waves: 1) Negative voltage pulse width, 2) inter-positive and negative voltage delay Switch Time, the parameters include the following:

the sum of the positive pulse width and the negative pulse width is 1-10us, and the width proportion of the positive pulse and the negative pulse can be independently set, and the corresponding pulse frequency is 1000KHz-100KHz.

The phase delay between the positive and negative pulses is increased and can be set between 1 and 10us to reduce the positive and negative double-phase offset effect.

The pulse interval is 100us-10000us.

The pulse group interval is 100us-10000us, and the pulse interval and the pulse group interval are combined to reduce the pain of patients in the ablation process.

The number of pulses in the pulse group is between 10 and 200, and the number of pulses in the pulse group can be set through a UI interface according to the required ablation depth of the target ablation part, so that accurate ablation is achieved.

In some possible embodiments, the discharge may also be achieved based on a pulse energy delivery algorithm of the cardiac cycle, in particular as follows:

as shown in fig. 9, the PEF discharge treatment time window employs a PEF pulse setting that releases once per second on average. The discharge and the heartbeat proportion are adjusted according to the total energy, for example, the discharge is carried out for 4 seconds at 60 hops and is carried out at 80 hops, and the discharge proportion is 80:60 =4: 3, namely every 4 heartbeats, discharging for 3 times and resting once. The PEF pulse train is released once per second, and the PEF supports 50-120 beats per minute of heart rate.

From the above, the energy of the invention can be arbitrarily adjustable, and a plurality of different energy levels can be output through pulse voltage adjustment. In practical designs, the frequency and the voltage are usually matched together, the high voltage needs corresponding high frequency as compensation, and when the voltage is reduced, the frequency can be reduced simultaneously to reduce the clinic.

Further, in this embodiment, a discharge protection module is further designed, and it can be understood that a discharge protection program and a mode which are stable, reliable, practical and convenient are designed to prevent any form of accidental discharge from causing irreversible damage accidents of non-therapeutic parts:

in this embodiment, referring to fig. 10, the discharge protection may specifically include:

1. pedal controller

2. The operator completes discharge ablation by manipulating the foot pedal for a preset length of time for each energy level. In each discharge process, the discharge time is controlled by the ablation energy meter respectively by selecting different energy levels.

3. And when the impedance measurement is carried out in real time and the discharge is output, the impedance change of the head end of the catheter is monitored through the impedance measurement module, the effective impedance discharge condition is 50-500Ohm, and when the impedance measurement value exceeds the range, namely, is lower than 50Ohm or is higher than 500Ohm, the discharge is immediately stopped. The discharge interval may be set based on actual clinical effects.

4. The heart is triggered in the absolute refractory period, and the pulse ablation instrument is controlled to only allow discharge treatment in the appointed range of the absolute refractory period, so that the ventricular fibrillation caused by pulse energy is prevented from endangering the life of a patient.

5. The heart rate threshold is met, discharge is allowed only when the heart rate threshold of the absolute refractory period of the heart is between 50 and 150BPM, and discharge is not allowed when any heart rate is outside the threshold. The heart rate is monitored by calculating trigger pulse signals of two consecutive absolute refractory periods, and the interval period between two trigger pulses corresponding to 50BPM is 1.2 seconds. The discharge is stopped after longer than 1.2 seconds, the interval period of 150BPM corresponding to two trigger pulses is 400 milliseconds, and the discharge is stopped after the signal is shorter than 400 milliseconds.

According to a third embodiment of the present invention, the present embodiment is a practical application method based on the above embodiment, and the ablation procedure is applied, specifically including the following steps:

s1, connecting a power supply, switching on a power switch, and confirming that a related status lamp is in a normal lighting state;

s2, confirming normal connection of the foot pedal;

s3, confirming that the body surface QRS monitor is connected, and displaying a normal ECG signal when the four lead electrodes on the body surface are normally attached;

s4, confirming that the negative plate attached with the discharge knife is positioned at a position outside the range of the three-dimensional mapping electrode;

s5, connecting a clinical radio frequency ablation catheter;

s6, connecting a saline water filling pump, and setting the saline water filling pump to low flow;

s7, connecting a multi-guide instrument;

s8, connecting a three-dimensional mapping system;

s9, connecting each external device with a universal ground wire;

s10, starting an operation, wherein an operator confirms the position of a focus target point, sets energy level, and presses down a pedal to complete single ablation;

s11, controlling the catheter to the next ablation position through a three-dimensional mapping system, setting energy level, and pressing down a pedal to complete ablation;

s12, repeating the step S8 to finish ablation of all positions;

s13, after the operation is finished, removing the ablation catheter and removing all electrode patches;

s14, turning off the power supply.

While the invention has been described in connection with specific embodiments thereof, it is to be understood that these drawings are included in the spirit and scope of the invention, it is not to be limited thereto.

Claims (10)

1. An open monopole pulsed electric field ablator, comprising:

the heart absolute refractory period monitoring module responds to the heart absolute refractory period monitored in real time and generates a corresponding absolute refractory period trigger signal;

the pulse energy triggering module is used for generating a pulse energy triggering signal corresponding to the absolute refractory period triggering signal;

the pulse electric field energy generator is connected with the pulse energy triggering module and responds to the pulse energy triggering signal to control the transmission of the pulse electric field by utilizing a preset energy generation triggering algorithm;

the energy separation module is externally connected with an ablation catheter and is used for outputting pulse energy of the pulse electric field to heart focus tissues for ablation treatment through the ablation catheter, wherein the pulse energy returns to an electrotome negative plate externally connected with the pulse energy triggering module through a human body, and backflow is achieved.

2. The open-type monopolar pulsed electric field ablator of claim 1, further comprising:

the intra-cavity electrode impedance detection module is used for controlling the pulse energy to be output to heart focus tissues by the ablation catheter within a preset impedance range;

and, open monopole pulsed electric field ablation appearance still has externally:

the three-dimensional mapping system is connected with the energy separation module and is used for three-dimensional modeling of heart focus;

the multi-conductor body surface electrode is connected with the heart absolute refractory period monitoring module and is used for monitoring body surface ECG signals, wherein the body surface ECG signals comprise electrophysiological signals representing the heart absolute refractory period;

and the multi-guide physiological instrument is connected with the energy separation module and is used for monitoring electrophysiological signals in the heart cavity.

3. The open monopole pulsed electric field ablation instrument of claim 1, wherein the ablation catheter is for at least one of pulsed energy ablation or radio frequency ablation.

4. The open monopole pulsed electric field ablation instrument of claim 1, wherein a tip electrode and a ring electrode inside the ablation catheter are connected across an external resistor such that a voltage difference between the tip electrode and the ring electrode is less than a safety threshold.

5. The open monopole pulsed electric field ablator of claim 2, wherein the energy separation module comprises:

the three-dimensional mapping and pressure sensing connector is connected with the three-dimensional mapping system;

the electrode comprises a large-head electrode and an annular electrode;

the three-dimensional mapping and pressure sensing connector, the connector for connecting the multi-conductivity physiological instrument and the intracavity electrode impedance detection module are connected with the large-head electrode and the annular electrode through signal wires, and relay switches are respectively arranged on the connected signal wires.

6. The open monopole pulsed electric field ablation instrument of claim 1, wherein the pulsed electric field energy generator produces a dc voltage in the range of 1900 volts to 3000 volts, with adjustable 100, 200, 500 volt spacing.

7. The open monopole pulsed electric field ablation instrument of claim 6, wherein the pulsed electric field energy generator discharges in a manner comprising: at least one of a monopolar monophasic mode or a monopolar biphasic mode.

8. The open monopole pulsed electric field ablator of claim 7, wherein the monopole monophasic mode comprises:

at least two pulses form a pulse burst, a burst interval is interposed between adjacent ones of said pulse bursts, and only the normal phase pulse burst.

9. The open monopolar pulsed electric field ablator of claim 7, wherein the monopolar biphasic mode comprises:

at least two pulses form a pulse group, a pulse group interval is inserted between two adjacent pulse groups, and the pulse group interval comprises a positive phase pulse train and a negative phase pulse train, and a delay is set between positive and negative voltages.

10. The open monopole pulsed electric field ablation instrument of claim 6, wherein the pulsed electric field energy generator further comprises a discharge protection module for preventing leakage conditions of the pulsed electric field energy generator.

Images