Eschar identification method and device for multi-electrode catheter

Abstract

The present invention belongs to the field of medical device technology. The present invention provides a method for identifying eschar of a multi-electrode catheter, comprising: measuring the blood impedance value, the impedance value close to the heart, and the impedance value between electrode pairs corresponding to the multi-electrode catheter; periodically calculating a first change value of the impedance value between the electrode pairs relative to the blood impedance value, and a second change value of the impedance value between the electrode pairs relative to the impedance value close to the heart; judging the eschar state of the multi-electrode catheter based on the first change value and the second change value; generating different types of reminder information according to the type of eschar state of the multi-electrode catheter. The present invention judges the state of the ablation catheter based on the impedance changes between multiple groups of electrode pairs. When eschar is identified on the catheter, it is used to guide the correct use of the ablation catheter during surgery, thereby improving surgical efficiency and safety.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a method and device for identifying eschar of a multi-electrode catheter. Background Art

[0002] Cardiac electrophysiology is a crucial branch of modern medicine. Arrhythmias (atrial fibrillation) are abnormal changes in heart rhythm and rate, primarily caused by altered electrical activity or conduction within the myocardium. Currently, ablation surgery is the primary treatment for electrophysiological disorders.

[0003] Common ablation treatment options include radiofrequency ablation, cryoablation, and pulsed electric field ablation. Radiofrequency ablation is the most common surgical treatment and is considered a traditional ablation method. All ablation methods work by inserting a catheter into the heart, directing the device's energy to the target tissue within the heart, thereby treating the diseased tissue.

[0004] Whether it's traditional radiofrequency ablation or the new pulsed electric field ablation, both aim to deliver energy to the target tissue. However, because the catheter is in a full-blood environment, some energy is inevitably lost to the bloodstream during energy delivery. Various existing technologies have investigated ways to improve energy delivery to the target tissue, such as ensuring good contact between the electrodes within the heart and the target tissue, or increasing the size of the balloon to squeeze the electrodes onto the target tissue. Regardless of the method, some energy is output from the device into the bloodstream. Excessive energy can cause blood to form eschars on the electrodes, and in severe cases, blood clots can form, leading to conditions such as myocardial infarction.

[0005] To prevent eschar formation, Johnson & Johnson has developed saline-irrigated catheter technology. This technology can lower the temperature of the ablation catheter and reduce the likelihood of eschar formation. However, this approach increases the difficulty of catheter fabrication and requires a saline-irrigation system. Summary of the Invention

[0006] The present invention provides a method and device for identifying eschar of a multi-electrode catheter, which overcome the above problems.

[0007] The technical solutions provided by the present invention are as follows:

[0008] In one aspect, the present invention provides a method for identifying eschar in a multi-electrode catheter, comprising:

[0009] Measure the blood impedance value corresponding to the multi-electrode catheter, the impedance value close to the heart, and the impedance value between the electrode pairs;

[0010] Periodically calculating a first change value of the impedance value between the electrode pairs relative to the blood impedance value, and a second change value of the impedance value between the electrode pairs relative to the heart impedance value;

[0011] determining an eschar state of the multi-electrode catheter based on the first change value and the second change value;

[0012] Different types of reminder information are generated according to the eschar status type of the multi-electrode catheter.

[0013] In some embodiments, the periodic calculation of a first change in the impedance value between the electrode pairs relative to the blood impedance value includes:

[0014] The first change value is calculated by the following formula:

[0015]

[0016] in,

[0017] C i,j min =min{Z ij};

[0018] C i,j max =max{Z ij};

[0019] S i1 is the first change value; C i,j min represents the minimum value of each electrode pair; C i,j max represents the maximum value of each electrode pair; Z i，j represents the impedance value measured by different electrode pairs; i represents different electrodes, depending on the selected electrodes (i≥2); t is any time; n is the number of ablation catheter electrodes.

[0020] In some embodiments, the periodic calculation of a second change in the impedance value between the electrode pairs relative to the heart impedance value includes:

[0021] The second change value is calculated by the following formula:

[0022]

[0023] Among them, S i2 is the second change value.

[0024] In some embodiments, judging the eschar state of the multi-electrode catheter based on the first change value and the second change value includes judging the eschar state of the multi-electrode catheter according to a catheter eschar judgment threshold, where the catheter eschar judgment threshold is (C1, C2), where:

[0025] C1∈{0,1000};

[0026] C2∈{-200,1000};

[0027] When the first change value is greater than C1 or the second change value is less than C2, the multi-electrode catheter is in an initial eschar state; otherwise, it is in a severe eschar state.

[0028] In some embodiments, generating different types of reminder information according to the eschar status type of the multi-electrode catheter includes:

[0029] When the multi-electrode catheter is in an initial eschar state, reminding the user of the multi-electrode catheter to terminate energy output and wait for the multi-electrode catheter to cool down before use;

[0030] When the multi-electrode catheter is in a severe eschar state, a user of the multi-electrode catheter is reminded to replace the multi-electrode catheter.

[0031] In some embodiments, the present invention further provides an eschar identification device for a multi-electrode catheter, comprising:

[0032] A measurement module is used to measure the blood impedance value corresponding to the multi-electrode catheter, the impedance value close to the heart, and the impedance value between the electrode pairs;

[0033] a calculation module for periodically calculating a first change value of the impedance value between the electrode pairs relative to the blood impedance value, and a second change value of the impedance value between the electrode pairs relative to the heart impedance value;

[0034] a judgment module, configured to judge the eschar state of the multi-electrode catheter based on the first change value and the second change value;

[0035] The reminder module is used to generate different types of reminder information according to the eschar state type of the multi-electrode catheter.

[0036] In some embodiments, the computing module is configured to:

[0037] The first change value is calculated by the following formula:

[0038]

[0039] in,

[0040] C i，j mib =min{Z ij};

[0041] C i，j max =max{Z ij};

[0042] S i1 is the first change value; C i，j minrepresents the minimum value of each electrode pair; C i，j max represents the maximum value of each electrode pair; Z i，j represents the impedance value measured by different electrode pairs; i represents different electrodes, depending on the selected electrodes (i≥2); t is any time; n is the number of ablation catheter electrodes.

[0043] In some embodiments, the computing module is configured to:

[0044] The second change value is calculated by the following formula:

[0045]

[0046] Among them, S i2 is the second change value.

[0047] In some embodiments, the judgment module is configured to judge the eschar state of the multi-electrode catheter according to a catheter eschar judgment threshold, where the catheter eschar judgment threshold is (C1, C2), where:

[0048] C1∈{0,1000};

[0049] C2∈{-200, 1000};

[0050] When the first change value is greater than C1 or the second change value is less than C2, the multi-electrode catheter is in an initial eschar state; otherwise, it is in a severe eschar state.

[0051] In some embodiments, the reminder module is used to:

[0052] When the multi-electrode catheter is in an initial eschar state, reminding the user of the multi-electrode catheter to terminate energy output and wait for the multi-electrode catheter to cool down before use;

[0053] When the multi-electrode catheter is in a severe eschar state, a user of the multi-electrode catheter is reminded to replace the multi-electrode catheter.

[0054] The method and device for identifying eschar on a multi-electrode catheter provided by the present invention have at least one of the following beneficial effects: the present invention judges the state of the ablation catheter based on the impedance changes between multiple groups of electrode pairs. When eschar is identified on the catheter, it is used to guide the correct use of the ablation catheter during surgery, thereby improving surgical efficiency and safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0056] Figure 1 is a schematic diagram of an embodiment of a method for identifying eschar in a multi-electrode catheter according to the present invention;

[0057] Figure 2 is a schematic diagram of an embodiment of a method for identifying eschar in a multi-electrode catheter according to the present invention;

[0058] Figure 3 It is a schematic diagram of an embodiment of an eschar identification device for a multi-electrode catheter of the present invention. DETAILED DESCRIPTION

[0059] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0060] To simplify the drawings, only the parts relevant to the present invention are schematically shown in each figure. They do not represent the actual structure of the product. Furthermore, to simplify the drawings and facilitate understanding, in some figures, only one of the components with the same structure or function is schematically depicted or labeled. As used herein, "one" not only means "only one" but also "more than one."

[0061] It should be further understood that the term "and / or" used in this specification and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

[0062] It should be noted that, unless otherwise specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they can refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediary; and internal communication between two components. Those skilled in the art will understand the specific meanings of these terms in the present invention based on the specific circumstances.

[0063] In addition, in the description of the present application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0064] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the specific embodiments of the present invention will be described below with reference to the accompanying drawings. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings and other embodiments can be obtained based on these drawings without inventive work.

[0065] In one embodiment, Figure 1 As shown, in one aspect, the present invention provides a method for identifying eschar in a multi-electrode catheter, comprising:

[0066] S101 measures the blood impedance value corresponding to the multi-electrode catheter, the impedance value close to the heart, and the impedance value between the electrode pairs.

[0067] Specifically, the ability to promptly identify the presence of eschar on the catheter can prevent the development of severe eschar, thereby reducing surgical risks for patients. Existing technologies primarily focus on reducing the formation of catheter eschar, but research on how to quickly identify eschar is lacking. Current product designs primarily explore the source of eschar formation to prevent it, but direct eschar identification has yet to be discovered.

[0068] This invention is an eschar identification algorithm based on catheter impedance changes. It utilizes impedance variations between different electrodes in a multi-electrode ablation catheter (with more than two electrodes). When blood proteins adhere to the catheter electrodes, the impedance between the electrodes increases. The more eschar present, the more pronounced the impedance increase. Eschar on the electrodes causes increased energy loss, generates heat within the heart, and can cause adverse reactions, endangering patient safety.

[0069] S102 periodically calculates a first change value of the impedance value between the electrode pairs relative to the blood impedance value, and a second change value of the impedance value between the electrode pairs relative to the heart impedance value.

[0070] S103: Determine the eschar state of the multi-electrode catheter based on the first change value and the second change value.

[0071] S104 generates different types of reminder information according to the eschar status type of the multi-electrode catheter.

[0072] The present invention judges the status of the ablation catheter based on the impedance changes between multiple groups of electrode pairs. When eschar is identified on the catheter, it is used to guide the correct use of the ablation catheter during surgery, thereby improving surgical efficiency and safety.

[0073] In one embodiment, the periodic calculation of a first change in the impedance value between the electrode pairs relative to the blood impedance value includes:

[0074] The first change value is calculated by the following formula:

[0075]

[0076] in,

[0077] C i，j min=min{Z ij};

[0078] C i，j max =max{Z ij};

[0079] S i1 is the first change value; C i，j min represents the minimum value of each electrode pair; C i，j max represents the maximum value of each electrode pair; Z i，j represents the impedance value measured by different electrode pairs; i represents different electrodes, depending on the selected electrodes (i≥2); t is any time; n is the number of ablation catheter electrodes.

[0080] In one embodiment, the periodic calculation of the second change value of the impedance value between the electrode pairs relative to the heart impedance value includes:

[0081] The second change value is calculated by the following formula:

[0082]

[0083] Among them, S i2 is the second change value.

[0084] In one embodiment, judging the eschar state of the multi-electrode catheter based on the first change value and the second change value includes judging the eschar state of the multi-electrode catheter according to a catheter eschar judgment threshold, where the catheter eschar judgment threshold is (C1, C2), where:

[0085] C1∈{0,1000};

[0086] C2∈{-200,1000};

[0087] When the first change value is greater than C1 or the second change value is less than C2, the multi-electrode catheter is in an initial eschar state; otherwise, it is in a severe eschar state.

[0088] Before the actual procedure, the catheter is configured to obtain the initial extreme values of the ablation catheter within the heart, as shown in Equations 1 and 2. During the procedure, the impedance between all electrode pairs is measured, and the reference indices Si1 and Si2 for electrode i are calculated based on the measured impedance values. The calculation process is shown in Equations 3 and 4.

[0089] The eschar status is determined based on the calculation results.

[0090]

[0091] Where:

[0092] i---represents different electrodes, depending on the selected electrodes (i≥2);

[0093] t---any time;

[0094] n---number of ablation catheter electrodes;

[0095] S i ---Represents the impedance change index of different electrodes;

[0096] C i,j min ---Represents the minimum value of each electrode pair;

[0097] C i,j max ---Represents the maximum value of each electrode pair;

[0098] Z i，j ---Represents the impedance measured by different electrode pairs (unit: Ω);

[0099] C1, C2---catheter eschar judgment threshold;

[0100] In summary, during the ablation process of a multi-electrode catheter, based on the measurement of multi-electrode impedance, the electrode status is judged and whether there is eschar on the ablation catheter electrode is identified, which helps to guide the energy output during the operation, improve the efficiency of catheter use, achieve the expected treatment effect, and at the same time improve surgical efficiency and reduce surgical risks.

[0101] In one embodiment, generating different types of reminder information according to the eschar status type of the multi-electrode catheter includes:

[0102] When the multi-electrode catheter is in an initial eschar state, reminding the user of the multi-electrode catheter to terminate energy output and wait for the multi-electrode catheter to cool down before use;

[0103] When the multi-electrode catheter is in a severe eschar state, a user of the multi-electrode catheter is reminded to replace the multi-electrode catheter.

[0104] In one embodiment, the catheter eschar identification method described in the present invention is based on the change of impedance to identify the eschar. It can also be based on the change of impedance by adding a fixed voltage to identify the change of current, or adding a fixed current to identify the change of voltage. Related similar methods are all within the scope of protection. The principle of this method is similar to identification based on changes in impedance. For example, if a fixed voltage of 50V is applied to the electrode pair, when the impedance environment in the blood changes, the current in the measuring electrode pair will change. When there is eschar on the electrode, the measured current value will become smaller. The principle of adding a fixed current to identify the change of voltage is the same as above, constant current voltage, and after the impedance changes, the measured voltage at both ends will change.

[0105] The present invention utilizes impedance changes between multi-electrode catheters for identification. When eschar forms between specific electrodes, it impedes the flow of electrons between the electrodes, reducing the current flowing between them at the same voltage. This energy loss, in turn, results in heat that increases catheter temperature, further causing eschar formation and creating a negative cycle. Effectively identifying resistance at the initial stage of a hazard can effectively prevent it from occurring.

[0106] In one embodiment, Figure 3 As shown, the present invention also provides an eschar identification device for a multi-electrode catheter, comprising:

[0107] The measurement module 101 is used to measure the blood impedance value corresponding to the multi-electrode catheter, the heart impedance value and the impedance value between the electrode pairs;

[0108] A calculation module 102 is configured to periodically calculate a first change in the impedance between the electrode pairs relative to the blood impedance value, and a second change in the impedance between the electrode pairs relative to the heart impedance value;

[0109] a judgment module 103, configured to judge the eschar state of the multi-electrode catheter based on the first change value and the second change value;

[0110] The reminder module 104 is configured to generate different types of reminder information according to the eschar status type of the multi-electrode catheter.

[0111] The present invention utilizes impedance changes between multi-electrode catheters for identification. When eschar forms between specific electrodes, it impedes the flow of electrons between the electrodes, reducing the current flowing between them at the same voltage. This energy loss, in turn, results in heat that increases catheter temperature, further causing eschar formation and creating a negative cycle. Effectively identifying resistance at the initial stage of a hazard can effectively prevent it from occurring.

[0112] In one embodiment, the computing module is configured to:

[0113] The first change value is calculated by the following formula:

[0114]

[0115] in,

[0116] C i，j min =min{Z ij};

[0117] C i，j max =max{Z ij};

[0118] Si1 is the first change value; C i，j min represents the minimum value of each electrode pair; C i，j max represents the maximum value of each electrode pair; Z i，j represents the impedance value measured by different electrode pairs; i represents different electrodes, depending on the selected electrodes (i≥2); t is any time; n is the number of ablation catheter electrodes.

[0119] In one embodiment, the computing module is configured to:

[0120] The second change value is calculated by the following formula:

[0121]

[0122] Among them, S i2 is the second change value.

[0123] In one embodiment, the judgment module is configured to judge the eschar state of the multi-electrode catheter according to a catheter eschar judgment threshold, wherein the catheter eschar judgment threshold is (C1, C2), where:

[0124] C1∈{0,1000};

[0125] C2∈{-200,1000};

[0126] When the first change value is greater than C1 or the second change value is less than C2, the multi-electrode catheter is in an initial eschar state; otherwise, it is in a severe eschar state.

[0127] In one embodiment, the reminder module is used to:

[0128] When the multi-electrode catheter is in an initial eschar state, reminding the user of the multi-electrode catheter to terminate energy output and wait for the multi-electrode catheter to cool down before use;

[0129] When the multi-electrode catheter is in a severe eschar state, a user of the multi-electrode catheter is reminded to replace the multi-electrode catheter.

[0130] In this embodiment, the parts that are the same as those in the above method embodiment will not be described in detail.

[0131] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented with electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0132] In the embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. Exemplarily, the system embodiments described above are merely schematic. Exemplarily, the division of the modules or units is merely a logical function division. There may be other division methods in actual implementation. Exemplarily, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0133] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0134] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0135] It should be noted that the above embodiments can be freely combined as needed. The above description is only a preferred embodiment of the present invention. It should be pointed out that those skilled in the art can make several improvements and modifications without departing from the principles of the present invention, and such improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A multi-electrode catheter eschar identification device, characterized in that: include: A measurement module is used to measure the blood impedance value corresponding to the multi-electrode catheter, the impedance value close to the heart, and the impedance value between the electrode pairs; a calculation module for periodically calculating a first change value of the impedance value between the electrode pairs relative to the blood impedance value, and a second change value of the impedance value between the electrode pairs relative to the heart impedance value; a judgment module, configured to judge the eschar state of the multi-electrode catheter based on the first change value and the second change value; a reminder module, configured to generate different types of reminder information according to the eschar state type of the multi-electrode catheter; The computing module is configured to: The first change value is calculated by the following formula: in, C i,jmin =min{Z ij }; C i,jmax =max{Z ij }; S i1 is the first change value; C i,jmin represents the minimum value of each electrode pair; C i,jmax represents the maximum value of each electrode pair; Z i，j represents the impedance value measured by different electrode pairs; i represents different electrodes, depending on the selected electrodes (i ≥ 2); t is any time; n is the number of ablation catheter electrodes; The second change value is calculated by the following formula: Among them, S i2 is the second change value; The judgment module is used to judge the eschar state of the multi-electrode catheter according to a catheter eschar judgment threshold, where the catheter eschar judgment threshold is (C1, C2), where: C1∈{0,1000}； C2∈{-200,1000}； When the first change value is greater than C1 or the second change value is less than C2, the multi-electrode catheter is in an initial eschar state; otherwise, it is in a severe eschar state.

2. The eschar identification device for a multi-electrode catheter according to claim 1, characterized in that: The reminder module is used to: When the multi-electrode catheter is in an initial eschar state, reminding the user of the multi-electrode catheter to terminate energy output and wait for the multi-electrode catheter to cool down before use; When the multi-electrode catheter is in a severe eschar state, a user of the multi-electrode catheter is reminded to replace the multi-electrode catheter.

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