Pressure sensing electrophysiology catheter

Abstract

The invention discloses a pressure sensing electrophysiology catheter. The electrophysiology catheter comprises a catheter body, and a pressure sensor assembly capable of sensing pressure is arranged at the far end of the catheter body. Wherein the pressure sensor assembly comprises a strain gauge capable of detecting pressure. The dimension of pressure sensing is increased, the pressure can be sensed, and the direction of the pressure can be obtained through calculation.

Description

Technical Field

[0001] The present application relates to the field of interventional surgery, and particularly to a pressure-sensing electrophysiological catheter. Background Art

[0002] In the medical field, catheters are widely used in various diagnostic and treatment processes, such as cardiac intervention, digestive endoscopy, etc. During the use of catheters, it is crucial to sense the pressure at the distal end of the catheter. In order to accurately sense and control the pressure at the distal end of the catheter, it is usually necessary to integrate a pressure sensor into the catheter. However, existing pressure sensors have many problems in terms of size, sensitivity, stability, etc. Currently, there are some pressure-sensing catheters on the market, but they usually adopt complex mechanical structures or expensive sensor technologies, which not only increase the manufacturing cost, but also may affect the accuracy of pressure sensing due to the installation accuracy and errors of the sensors.

[0003] Therefore, there is a need for a catheter with a simple structure, low manufacturing cost, and capable of accurately sensing pressure now. Summary of the Invention

[0004] In order to solve the problems existing in the prior art, the present application provides a pressure-sensing electrophysiological catheter.

[0005] The specific technical solution of the present application is as follows:

[0006] 1. A pressure-sensing electrophysiological catheter, wherein the electrophysiological catheter includes a catheter body, and a pressure sensor assembly capable of sensing pressure is provided at the distal end of the catheter body;

[0007] The pressure sensor assembly can detect the magnitude and direction of the force it receives.

[0008] 2. The electrophysiological catheter according to item 1, wherein the pressure sensor assembly includes a strain gauge assembly capable of detecting pressure; the strain gauge assembly includes more than two strain gauges; preferably, three strain gauges are provided.

[0009] 3. The electrophysiological catheter according to item 1 or 2, wherein the plurality of strain gauges are arranged circumferentially along the catheter body, and the centers of the plurality of strain gauges are all located in the same radial cross-section of the catheter body;

[0010] Preferably, the strain gauges are evenly arranged along the circumferential direction of the catheter body.

[0011] 4. The electrophysiological catheter according to any one of items 1 to 3, wherein the pressure sensor assembly further includes a radial strain gauge; one radial strain gauge is provided.

[0012] 5. The electrophysiological catheter according to any one of items 1 to 4, wherein a half-bridge circuit capable of detecting the change in the resistance of the strain gauge is formed between the strain gauge and the radial strain gauge;

[0013] The plurality of strain gauges are connected in parallel, and all the strain gauges are respectively connected in series with the radial strain gauge.

[0014] 6. The electrophysiological catheter according to any one of items 1 to 5, wherein a stainless steel body is provided at the distal position of the catheter body, and the pressure sensor assembly is provided at the distal position of the stainless steel body; a softening hole is formed in the stainless steel body; the softening hole is formed at a position of the stainless steel body close to the proximal end;

[0015] Preferably, the softening hole is formed by laser engraving.

[0016] 7. The electrophysiological catheter according to any one of items 1 to 6, wherein a patch substrate is provided on the stainless steel body, and the pressure sensor assembly is bonded to the patch substrate assembly.

[0017] 8. The electrophysiological catheter according to any one of items 1 to 7, wherein the patch substrate is fixedly connected to the stainless steel body; an outer cladding is provided on the outer periphery of the stainless steel body; the outer cladding is sleeved on the outer periphery of the patch substrate and fixes the patch substrate on the stainless steel body;

[0018] Preferably, the outer cladding is a polymer material layer or a silicone layer;

[0019] More preferably, the outer cladding is a silicone layer.

[0020] 9. The electrophysiological catheter according to item 2,

[0021] When the electrophysiological catheter is under pressure, the magnitude and direction of the pressure are calculated by obtaining the micro-strain values of the three strain gauges.

[0022] 10. The electrophysiological catheter according to item 9,

[0023] The axial component force of the pressure is obtained using formula 1:

[0024]

[0025] ε 1 、ε 2 、ε 3 are the micro-strain values corresponding to the three strain gauge pressure sensors respectively;

[0026] E is the elastic modulus of the strain gauge pressure sensor,

[0027] A is the cross-sectional area,

[0028] Faxi is the axial component force.

[0029] 11. The electrophysiological catheter according to item 9,

[0030] Calculating the radial component force of the pressure includes separately calculating the magnitude and direction of the radial component force.

[0031] 12. The electrophysiological catheter according to item 9,

[0032] Select one of the strain gauge pressure sensors as the reference strain gauge, and the microstrain value corresponding to the reference strain gauge is ε 1 ; the microstrain values corresponding to the other two strain gauge pressure sensors are ε 2 and ε3 respectively;

[0033] The radial component force of the pressure satisfies the following formulas 2 to 4:

[0034]

[0035] Among them, E is the elastic modulus of the material, A is the cross-sectional area, I is the moment of inertia of the cross-section, and the calculation formula for the moment of inertia of a circular cross-section is: F tan is the radial component force, F axi is the axial component force, H is the axial distance from the force application point on the rigid body to the strain gauge pressure sensor, R is the radius of the cross-sectional circle; the angle θ is the central angle corresponding to the radial component force F tan and the reference strain gauge at the center of the cross-section; both H and R are known constants;

[0036] Calculate the magnitude and direction of the radial component force F tan .

[0037] 13. The electrophysiological catheter according to item 9, calculate the radial component force F tan according to the magnitude of and the angle θ, and calculate the radial component force F tan ; and combine with the axial component force F axi to calculate the magnitude and direction of the pressure.

[0038] 14. A method for pressure sensing using the electrophysiological catheter according to any one of items 1 to 13, which includes:

[0039] Performing an interventional operation using an electrophysiological catheter containing three strain gauges and one radial strain gauge;

[0040] The three strain gauges form a half-bridge circuit;

[0041] The three strain gauges are connected in parallel and in series with the radial strain gauge;

[0042] Measuring the microstrain values of the three strain gauges when the electrophysiological catheter is under pressure;

[0043] Calculate the magnitude of the axial component of the pressure based on the micro-strain value of the strain gauge;

[0044] Calculate the radial component of the pressure based on the relationship between the micro-strain values of the three strain gauges and the pressure;

[0045] Calculate the pressure based on the radial and axial components of the pressure.

[0046] Advantages

[0047] An electrophysiological catheter with pressure sensing of the present application has the following advantages:

[0048] 1. The integrated patch-type pressure sensor technology is adopted. First, the strain gauges of the three pressure sensors are pasted onto the patch substrate at specified angles and positions, and then the substrate is wrapped with silicone or other polymer materials to the specified position on the stainless steel body of the catheter. The advantage of this is that the pasting positions and angles of the three pressure sensors can be more precise, and the operation difficulty in actual production is also reduced.

[0049] 2. By selecting silicone or other polymer materials with good pressure conductivity and biocompatibility to wrap the patch substrate and the strain gauge silicone, the protection of the pressure sensor is increased, and its service life and stability are improved.

[0050] 3. The design of pasting three strain gauges at a 120-degree angle is adopted, increasing the dimension of pressure sensing. Not only can the magnitude of the force be sensed, but also the direction of the force can be calculated through calculation.

[0051] 4. The stainless steel body is engraved with a specified shape by laser etching technology, reducing the rigidity of the stainless steel, so that the strain gauge can better respond to the change of force.

[0052] 5. Simple manufacturing processes and equipment are adopted, reducing the manufacturing cost, which is beneficial to large-scale production and application. Description of the Drawings

[0053] Figure 1 is a schematic diagram of the overall structure of the electrophysiological catheter of the present application.

[0054] In the figure, 1, catheter body; 2, stainless steel body; 3, strain gauge; 4, softening hole; 5, patch substrate; 6, head electrode. Detailed Embodiments

[0055] The present application will be described in detail below. Although specific embodiments of the present application are shown, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present application can be more thoroughly understood and the scope of the present application can be completely conveyed to those skilled in the art.

[0056] It should be noted that certain terms are used in the description and claims to refer to specific components. Those skilled in the art should understand that technicians may use different terms to refer to the same component. The description and claims of this specification do not distinguish components by the difference in terms, but by the difference in the functions of the components. As mentioned throughout the description and claims, the terms "comprising" or "including" are open-ended terms and should be interpreted as "including but not limited to". The subsequent description in the specification is the preferred embodiment for implementing the present application. However, the description is for the purpose of the general principles of the specification and is not used to limit the scope of the present application. The protection scope of the present application shall be determined by what is defined in the appended claims.

[0057] Reference Figure 1 , the present application provides a pressure-sensing electrophysiological catheter. A pressure-sensing electrophysiological catheter, wherein the electrophysiological catheter includes a catheter body 1, and a pressure sensor assembly capable of sensing pressure is provided at the distal end of the catheter body 1.

[0058] In the field of interventional medicine, the end close to the operator is defined as the "proximal end", and the end far from the operator is defined as the "distal end". For an elongated object, the direction parallel to its length extension direction is defined as the "axial direction"; for an object with a circular cross-section, the direction around its axial direction is defined as the "circumferential direction". For a cylindrical object, its extension direction is defined as the "axial direction", and the radial direction of the circular cross-section is defined as the "radial direction".

[0059] When the catheter body 1 moves inside the human body, the catheter body 1 will come into contact with tissues, and then the catheter body 1 will be subjected to the resistance force of the tissues. The pressure sensor assembly located at the distal end of the catheter body 1 is used to detect the resistance force received by the catheter body at the distal end. Among them, the resistance force of the human tissues detected by the pressure sensor assembly on the catheter body 1 includes the magnitude and direction of the force.

[0060] After the operator knows the magnitude and direction of the resistance force through the pressure sensor assembly, the operator can then know the situation of the catheter body 1, and then can greatly reduce the probability of the operator causing harm to the human body during the operation. Further, according to the magnitude and direction of the resistance force, when the catheter body is being transported deeper inside the human body, before the catheter body is about to pierce the tissue, the operator can prevent the catheter body 1 from going deeper. While reducing the damage of the catheter body 1 to the tissue, it also helps to smoothly transport the catheter body 1 to the target position inside the human body.

[0061] The pressure sensor assembly includes a head electrode 6 arranged at the end position of the distal end of the catheter body 1; the head electrode 6 is located at the farthest end of the catheter body 1; when the catheter body 1 advances inside the human body, the head electrode 6 is located at the front end of the catheter body 1, and the head electrode 6 is used to contact human tissue and sense the pressure exerted on the catheter body 1.

[0062] Wherein, the pressure sensor assembly includes a strain gauge assembly capable of detecting pressure, and the strain gauge assembly includes more than two strain gauges; preferably, three strain gauges are provided.

[0063] In the present application, a strain gauge pressure sensor is used to detect the abutment force applied to the catheter body 1 .

[0064] Since the catheter body 1 needs to pass through the human blood vessels to enter the human body, the size of the catheter body 1 is limited to a certain extent, while the strain gauge 3 can be kept in a small size while ensuring sufficient accuracy. Therefore, in this application, the strain gauge 3 is installed at the distal end of the catheter body 1.

[0065] The number of the strain gauges 3 is more than two.

[0066] The strain gauge 3 is used to detect the abutment force. When the tissue applies the abutment force to the catheter body 1, the strain gauge 3 can detect the pressure at its location.

[0067] Since the working principle of the strain gauge 3 is that the strain gauge 3 is deformed by force, and the magnitude of the force is measured by the magnitude of the deformation. Therefore, multiple strain gauges 3 are used in the present application to detect the forces at different positions of the circumference of the catheter body 1, and then the abutment force is reversely deduced according to the difference in the force components of the abutment force at different positions. Then the magnitude and direction of the abutment force are determined. Therefore, at least two strain gauges 3 are provided.

[0068] Specifically, the number of the strain gauges 3 is: 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15.

[0069] Preferably, three strain gauges 3 are provided.

[0070] In the present application, since the position of the catheter body 1 changes at any time when it goes deep into the human body, there is uncertainty in the abutment force on the catheter body 1. Therefore, the force on the catheter body 1 is more often a force in three-dimensional space.

[0071] When determining and calculating the magnitude and direction of the abutting force, an equation can be listed based on the relationship between the three component forces of the abutting force in the three directions of the x, y, and z axes in a three-dimensional space. Therefore, in this application, three strain gauges 3 are provided. By using the data of different positions detected by the three strain gauges 3, an equation is listed, and then the component forces of the abutting force are calculated indirectly to calculate the abutting force. Or the magnitude and direction of the abutting force can be directly calculated.

[0072] The multiple strain gauges 3 are arranged along the circumferential direction of the catheter body 1, and the centers of the multiple strain gauges 3 are all located in the same radial cross-section of the catheter body 1;

[0073] Preferably, the strain gauges 3 are evenly arranged along the circumferential direction of the catheter body 1.

[0074] When the catheter body 1 penetrates deep inside the human body, its elastic deformation in the axial direction is negligible. Therefore, the catheter body 1 is a rigid body in the axial direction, and thus the component forces of the entire catheter body 1 in the axial direction are equal everywhere. Therefore, in order to reduce the calculation intensity of calculating the abutting force based on the strain gauges 3, by arranging the strain gauges 3 on the same cross-section, the distance component of the pressure sensor in the axial direction can be offset, and thus the calculation of the abutting force becomes more convenient.

[0075] Due to the variability of the forces on the catheter body 1 during the process of penetrating deep into the human body, in order to enable the strain gauges 3 to detect a greater range of abutting forces. Therefore, the strain gauges 3 are evenly arranged along the circumferential direction of the catheter body 1 so as to be able to handle more force conditions.

[0076] The pressure sensor assembly further includes a radial strain gauge; one radial strain gauge is provided.

[0077] A half-bridge circuit capable of detecting the resistance change of the strain gauges 3 is formed between the strain gauges 3 and the radial strain gauge.

[0078] The multiple strain gauges 3 are connected in parallel, and all the strain gauges 3 are connected in series with the radial strain gauge.

[0079] The radial strain gauge and the strain gauges 3 together form a half-bridge circuit or a full-bridge circuit, preferably a half-bridge circuit; for temperature compensation of the strain gauges 3 to improve the detection accuracy of the strain gauges 3.

[0080] In a specific embodiment, a half-bridge circuit is formed between each strain gauge 3 and the radial strain gauge respectively; enabling the half-bridge circuit to perform temperature compensation on each strain gauge 3 respectively, thereby reducing the error caused by temperature during the detection of the strain gauges 3, and further improving the accuracy of the strain gauges in detecting forces. Further improving the accuracy of the electrophysiological catheter in pressure sensing.

[0081] A stainless steel body 2 is provided at the distal position of the catheter body 1, and the pressure sensor assembly is provided at the distal position of the stainless steel body 2.

[0082] The stainless steel body 2 is used to carry the pressure sensor; the distal end of the catheter body 1 is connected to the stainless steel body 2, and then the pressure sensor assembly is installed at the distal position of the stainless steel body 2. The stainless steel body 2 is used to connect the pressure sensor assembly and the catheter body 1.

[0083] A softening hole 4 is provided in the stainless steel body 2; the softening hole 4 is provided at a position of the stainless steel body 2 close to the proximal end;

[0084] Preferably, the softening hole 4 is formed by laser engraving.

[0085] The stainless steel body 2 is a hollow tubular structure. The softening hole 4 is a through hole in the stainless steel body 2. Therefore, under the action of the softening hole 4, the stainless steel body 2 ensures sufficient service strength and greatly increases the elasticity of the stainless steel body 2. Therefore, when the pressure sensor assembly is subjected to a contact force; the stainless steel body 2 can deform, so that the pressure sensor has a buffer area. The trend that the contact force gradually increases as the catheter body 1 penetrates is alleviated, so that the operator has a longer time to control the magnitude of the contact force.

[0086] On the other hand, the stainless steel body 2 provided with the softening hole 4 can also provide elastic deformation, so that when the force of the catheter body 1 and the pressure sensor assembly contacting the tissue is too large, the axial acting force of the catheter body 1 and the pressure sensor assembly can be offset, thereby reducing the stab injury to the tissue.

[0087] A patch substrate 5 is provided on the outer surface of the stainless steel body 2, and the pressure sensor assembly is bonded to the patch substrate 5.

[0088] The patch substrate 5 is the base of the strain gauge 3. The patch substrate 5 can be bonded to the stainless steel body 2.

[0089] The strain gauge 3 is bonded to the patch substrate 5.

[0090] Specifically, in the present application, the patch substrate 5 is a layer of base material attached to the outer surface of the stainless steel body 2.

[0091] When the strain gauge 3 is installed, first, three strain gauges 3 are installed or bonded to the patch substrate 5; then the patch substrate 5 is bonded to the outer peripheral surface of the stainless steel body 2.

[0092] The size of the patch substrate 5 is adapted to the outer peripheral size of the stainless steel body 2, enabling the patch substrate 5 to fix the strain gauge 3 on the stainless steel body 2. Moreover, a patch substrate 5 with a suitable size can reduce the influence of the patch substrate 5 on the stainless steel body 2 and the strain gauge 3. For example, excessive lamination at the joint of the patch substrate 5 may cause the strain gauge 3 to shift, etc., thereby increasing the positioning accuracy of the strain gauge 3.

[0093] When the strain gauge 3 is installed on the stainless steel body 2, since the stainless steel body 2 is cylindrical, the strain gauge 3 not only needs to be aligned axially on the stainless steel body 2, but also needs to be evenly arranged circumferentially, that is, the distance between any two of the three strain gauges 3 is equal. This makes it difficult to position the strain gauge 3 when it is fixed on the stainless steel body 2, which will lead to a decrease in the pressure detection accuracy of the strain gauge 3, a decrease in the yield rate of the electrophysiological catheter, and an increase in the manufacturing cost of the electrophysiological catheter.

[0094] Therefore, when the strain gauge 3 is installed on the stainless steel body 2, first fix the strain gauge 3 on the patch substrate 5. The patch substrate 5 is a layer structure, so it is easier for the strain gauge 3 to be accurately positioned on the patch substrate 5. It is easier to position the strain gauge 3 on the patch substrate 5 compared to directly positioning it on a flat surface on a cylindrical surface, which helps to improve the yield rate of the electrophysiological catheter and reduce the manufacturing cost of the electrophysiological catheter. After the strain gauge 3 is fixedly attached to the patch substrate 5, then directly attach the patch substrate 5 to the preset position on the stainless steel body 2. Since the strain gauge 3 has been accurately positioned on the patch substrate 5, the installation of the strain gauge 3 is achieved after the patch substrate 5 is attached to the stainless steel body 2.

[0095] The patch substrate 5 is used to fix the strain gauge 3 on the stainless steel body 2, enabling the strain gauge 3 to detect the contact force.

[0096] The patch substrate 5 is fixedly connected to the stainless steel body 2. An outer coating is provided on the outer periphery of the stainless steel body 2. The outer coating is sleeved on the outer periphery of the patch substrate 5 and fixes the patch substrate 5 on the stainless steel body 2.

[0097] Preferably, the outer coating is a polymer material layer or a silicone layer.

[0098] More preferably, the outer coating is a silicone layer.

[0099] The outer coating wraps the patch substrate 5, the strain gauge 3, and the stainless steel body 2. At the same time, the outer coating is a tightly insulating material that can be used to isolate its internal structure from external air or body fluids in the human body.

[0100] Meanwhile, since through holes of the softening holes 4 are formed in the stainless steel body 2, an outer cladding is used to wrap the stainless steel body 2, thereby reducing the entry of gas or liquid from the stainless steel body 2 into the inside of the catheter body 1.

[0101] When the electrophysiological catheter is under pressure, the magnitude and direction of the pressure are calculated by obtaining the micro-strain values of the three strain gauges 3.

[0102] The axial component of the pressure is obtained using Equation 1:

[0103]

[0104] ε 1 、ε 2 、ε 3 are the micro-strain values corresponding to the three strain gauges respectively;

[0105] E is the elastic modulus,

[0106] A is the cross-sectional area,

[0107] F axi is the axial component.

[0108] When the electrophysiological catheter penetrates deep inside the human body, the pressure exerted on the electrophysiological catheter is the abutting force.

[0109] Calculating the radial component of the pressure includes calculating the magnitude and direction of the radial component respectively.

[0110] Select one of the strain gauges 3 as the reference strain gauge, and the micro-strain value corresponding to the reference strain gauge is ε 1 ; the micro-strain values corresponding to the other two strain gauges 3 are ε 2 and ε 3 ;

[0111] The radial component of the pressure satisfies the following Equations 2-4:

[0112]

[0113] Wherein, E is the elastic modulus of the material, A is the cross-sectional area, I is the cross-sectional moment of inertia, and the cross-sectional moment of inertia calculation formula for a circle is: F tan is the radial component, F axi is the axial component, H is the axial distance from the force application point on the rigid body to the strain gauge, R is the radius of the cross-sectional circle; the angle θ is the central angle corresponding to the radial component F tan and the reference strain gauge at the center of the cross-section; both H and R are known constants;

[0114] In this application, H is the distance between the force application point of the strain gauge 3 and the tip electrode 6.

[0115] Combining the three equations of Formulas 2 to 4, the radial component force F is calculated. tan The magnitude and direction are obtained.

[0116] Based on the magnitude of the radial component force F tan and the angle θ, the radial component force F tan is calculated; and in combination with the axial component force F axi the magnitude and direction of the pressure are calculated.

[0117] A display component is connected to the electrophysiological catheter. The display component's structural pressure sensor component is based on the calculated force result detected; then the display component displays the magnitude and direction of the pressure received by the electrophysiological catheter, and the user can directly view the force condition of the electrophysiological catheter or the catheter body 1 through the display component.

[0118] A method for pressure sensing using the above electrophysiological catheter includes:

[0119] Performing an interventional operation using an electrophysiological catheter containing three strain gauges and one radial strain gauge;

[0120] The strain gauges can sense pressure; when the electrophysiological catheter is under pressure, the strain gauges can generate electrical signals accordingly, and based on the strength of the electrical signals, the magnitude of the component force of the pressure at the position where the strain gauges are located is sensed. Then, based on the positions of the multiple strain gauges and the magnitudes of the component forces sensed by the strain gauges, the magnitude and direction of the pressure are calculated.

[0121] The three strain gauges form a half-bridge circuit;

[0122] The three strain gauges are connected in parallel and in series with the radial strain gauge;

[0123] The half-bridge circuit and the full-bridge circuit are used for temperature compensation of the strain gauges, reducing the measurement error caused by the deformation of the strain gauges due to thermal expansion and contraction during use. The measurement accuracy of the strain gauges for pressure is improved.

[0124] Measure the micro-strain values of the three strain gauges when the electrophysiological catheter is under pressure;

[0125] The three strain gauges are evenly arranged on the electrophysiological catheter. Therefore, when the electrophysiological catheter is under pressure, the component forces of the three strain gauges at different positions will also change with the direction of the pressure.

[0126] Therefore, based on the micro-strain values of the strain gauges, the magnitude of the component force of the pressure at the position of the strain gauges can be calculated, and then based on the magnitudes of the component forces of the three strain gauges in three directions and the positional relationship between the three strain gauges and the force application point of the pressure, the magnitude and direction of the pressure are calculated.

[0127] Calculate the magnitude of the axial component of the pressure based on the micro-strain values of the strain gauges;

[0128] Calculate the radial component of the pressure based on the relationship between the micro-strain values of the three radial strain gauges and the pressure;

[0129] When calculating the pressure, it is necessary to calculate the components of the pressure in the axial direction and the radial direction along the electrophysiological catheter respectively, and then calculate the resultant force, and then calculate the pressure.

[0130] When calculating the axial component of the pressure, use Equation 1 to calculate:

[0131]

[0132] ε 1 、ε 2 、ε 3 are the micro-strain values corresponding to the three strain gauges respectively;

[0133] E is the elastic modulus,

[0134] A is the cross-sectional area,

[0135] F axi is the axial component.

[0136] When calculating the radial component of the pressure, use Equations 2-4; calculate the magnitude and direction of the radial component.

[0137]

[0138]

[0139] Among them, E is the elastic modulus of the material, A is the cross-sectional area, I is the moment of inertia of the cross-section, and the formula for calculating the moment of inertia of a circular cross-section is: F tan is the radial component, F axi is the axial component, H is the axial distance from the force application point on the rigid body to the strain gauge, R is the radius of the cross-sectional circle; the angle θ is the central angle corresponding to the radial component F tan and the reference strain gauge at the center of the cross-section; both H and R are known constants;

[0140] Calculate the pressure based on the radial and axial components of the pressure.

[0141] In summary, the present application provides a pressure-sensing electrophysiological catheter, with a pressure sensor assembly disposed at the head end of the electrophysiological catheter for sensing the pressure exerted on the catheter body 1. When the electrophysiological catheter is inserted deep into the human body, the head electrode 6 at the front end of the electrophysiological catheter will be subjected to pressure, and the strain gauge 3 will sense the pressure on the head electrode 6. Subsequently, the strain gauge 3 will deform; and different magnitudes of current will be generated according to different positions of the strain gauge 3. Then, based on the magnitude of the current on the strain gauge 3 and the position of the strain gauge 3, the axial component force and the radial component force of the pressure on the electrophysiological catheter, including their magnitudes and directions, are calculated respectively. Finally, the magnitude and direction of the pressure are calculated based on the axial component force and the radial component force, and are finally displayed in the display component. The user can then view the results in the display component.

[0142] This specific embodiment is only an interpretation of the present application and does not limit the present application. After reading this specification, those skilled in the art can make modifications to this embodiment without creative contributions as needed, but as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A pressure-sensing electrophysiological catheter, wherein: The electrophysiological catheter comprises a catheter body, and a pressure sensor assembly capable of sensing pressure is arranged at the distal end of the catheter body; The pressure sensor assembly can detect the magnitude and direction of the force it is subjected to.

2. The electrophysiological catheter according to claim 1, wherein the pressure sensor assembly comprises a strain gauge assembly capable of detecting pressure; the strain gauge assembly comprises more than two strain gauges; preferably, three strain gauges are provided.

3. The electrophysiological catheter according to claim 1 or 2, wherein the plurality of strain gauges are arranged along the circumference of the catheter body, and the centers of the plurality of strain gauges are all located in the same radial cross section of the catheter body; Preferably, the strain gauges are evenly arranged along the circumference of the catheter body. 4 . The electrophysiological catheter according to claim 1 , wherein the pressure sensor assembly further comprises a radial strain gauge; and one radial strain gauge is provided.

5. The electrophysiological catheter according to any one of claims 1 to 4, wherein the strain gauge and the radial strain gauge form a half-bridge circuit capable of detecting a change in resistance of the strain gauge; The multiple strain gauges are connected in parallel, and all the strain gauges are connected in series with the radial strain gauges respectively.

6. The electrophysiological catheter according to any one of claims 1 to 5, wherein a stainless steel body is provided at the distal end of the catheter body, and the pressure sensor assembly is provided at the distal end of the stainless steel body; a softening hole is provided on the stainless steel body; and the softening hole is provided at a position close to the proximal end of the stainless steel body; Preferably, the softening hole is formed by laser engraving; Further preferably, a patch substrate is provided on the stainless steel body, and the pressure sensor component is bonded to the patch substrate component.

7. The electrophysiological catheter according to any one of claims 1 to 6, wherein the patch substrate is fixedly connected to the stainless steel body; an outer sheath is arranged around the stainless steel body; the outer sheath is sleeved around the patch substrate and fixes the patch substrate on the stainless steel body; Preferably, the outer layer is a polymer material layer or a silica gel layer; Further preferably, the outer coating is a silica gel layer; Further preferably, when the electrophysiological catheter is subjected to pressure, the magnitude and direction of the pressure are calculated by obtaining microstrain values ​​of the three strain gauges.

8. The electrophysiological catheter according to claim 7, Using Equation 1, we find the axial component of pressure: ε1, ε2, and ε3 are the microstrain values ​​corresponding to the three strain gauge pressure sensors; E is the elastic modulus of the strain gauge pressure sensor, A is the cross-sectional area, F axi is the axial force component; Preferably, calculating the radial component of pressure includes respectively calculating the magnitude and direction of the radial component.

9. The electrophysiological catheter according to claim 8, One of the strain gauge pressure sensors is selected as the reference strain gauge, and the microstrain value corresponding to the reference strain gauge is ε1; the microstrain values ​​corresponding to the other two strain gauge pressure sensors are ε2 and ε3 respectively; The radial component of pressure satisfies the following formulas 2 to 4: in, E is the elastic modulus of the material, A is the cross-sectional area, and I is the cross-sectional moment of inertia. The calculation formula for the cross-sectional moment of inertia of a circle is: F tan is the radial force, F axi is the axial force component, H is the axial distance from the force point on the rigid body to the strain gauge pressure sensor, R is the radius of the cross-sectional circle; angle θ is the radial force component F tan The central angle between the reference strain gauge and the center of the cross section; H and R are both known constants; The radial force F is calculated tan size and direction; Preferably, according to the radial force F tan The radial force F is calculated by the magnitude and angle θ tan ; and combined with the axial force F axi Calculate the magnitude and direction of the pressure.

10. A method for pressure sensing using an electrophysiological catheter according to any one of claims 1 to 9, comprising: Interventional procedures were performed using an electrophysiology catheter containing three strain gauges and one radial strain gauge; The three strain gauges form a half-bridge circuit; Three strain gauges are connected in parallel and in series with the radial strain gauge; Measure the microstrain values ​​of the three strain gauges when the electrophysiology catheter is subjected to pressure; Calculate the magnitude of the axial component of pressure based on the microstrain value of the strain gauge; The radial component of pressure is calculated based on the relationship between the microstrain values ​​of the three strain gauges and the pressure; The pressure is calculated from the radial and axial components of the pressure.

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