CN212234431U

CN212234431U - Pressure measurement catheter and intravascular pressure gradient sensing system

Info

Publication number: CN212234431U
Application number: CN202022163454.4U
Authority: CN
Inventors: 董樑; 丘信炯; 张庭超
Original assignee: Hangzhou Valgen Medtech Co Ltd
Current assignee: Hangzhou Valgen Medtech Co Ltd
Priority date: 2020-09-27
Filing date: 2020-09-27
Publication date: 2020-12-29
Anticipated expiration: 2030-09-27

Abstract

The utility model discloses a pressure measurement pipe and intravascular pressure gradient sensing system. The pressure measurement catheter includes a pressure measurement assembly and a tubular body. The body extends axially between a proximal end and a distal end. The load cell assembly comprises a first load cell and at least one second load cell, and the first load cell and the at least one second load cell are arranged on the peripheral wall of the body and are arranged at intervals along the axial direction of the body. The at least one second load cell is closer to the distal end of the body than the first load cell. The pressure measurement catheter may simultaneously measure the proximal vessel pressure and the distal vessel pressure to determine the fractional coronary flow reserve FFR. The pressure measurement catheter reduces the operation time and the plaque risk caused by the back-and-forth operation of the guide wire in and out in operation, reduces the FFR value deviation caused by extra resistance caused by the blood vessel restoring curvature after the guide wire is withdrawn, and improves the measurement accuracy. Meanwhile, the operation of an operator is facilitated, and the risk of the patient and the detection cost are reduced.

Description

Pressure measurement catheter and intravascular pressure gradient sensing system

Technical Field

The utility model relates to an intervene the medical instrument field, especially relate to pressure measurement pipe and intravascular pressure gradient sensing system.

Background

Fractional Flow Reserve (FFR) of the coronary artery refers to the maximum blood Flow of the vessel in the presence of a stenotic lesion as compared to the maximum blood Flow that would have been obtained if the stenotic lesion were not present. Simplified definition is the ratio of the mean pressure in the stenotic distal coronary artery (Pd) to the mean pressure in the coronary artery oral aorta (Pa) in the maximal hyperemic state of the myocardium. In recent years, functional examination of Coronary vessels, such as FFR, has been demonstrated in the diagnostic value of Percutaneous Coronary Intervention (PCI) and is used in evidence-based medicine.

Currently, FFR detection is typically achieved using a guide wire or catheter with a pressure chip and a guide wire attached to the tip to obtain FFR data. During operation, firstly, a guide wire is arranged in the guide catheter in a penetrating mode and sent to a coronary artery, then the pressure Pa of the proximal end of a blood vessel is measured, then the guide wire is pushed to the far end to measure the pressure Pd of a lesion at the far end of the blood vessel, then the guide wire is slowly withdrawn, pressure values Pd at multiple positions in the withdrawing process are measured, and the condition of ischemia at the far end of the lesion blood vessel is judged according to the ratio of Pd to Pa. The existing FFR guide wire technology has multiple defects, firstly, the guide wire design for attaching a pressure chip and a guide wire brings difficulty in operation, particularly when complex coronary artery lesion intervention operations are encountered, such as bifurcation, multiple lesions, diffuse long lesions, calcification and the like, the guide wire needs to be exchanged back and forth, time and labor are wasted, the success rate of the guide wire passing is reduced, complications are easy to occur, the physical strength and time consumption of operators are increased, the risk and economic burden of patients are increased, and the operation defect is particularly obvious; secondly, in the withdrawal process, the blood vessel straightened by the guide wire is distorted again and is easily misjudged to be the pressure value change caused by the pathological changes of the blood vessel, so that the accuracy of the measured value is reduced.

SUMMERY OF THE UTILITY MODEL

In order to solve the above technical problem or at least partially solve the above technical problem, the present invention provides a pressure measurement catheter, including:

a body having a tubular shape, the body extending axially between a proximal end and a distal end; and

the pressure measuring assembly comprises a first pressure measuring unit and at least one second pressure measuring unit, the first pressure measuring unit and the at least one second pressure measuring unit are arranged on the peripheral wall of the body and are arranged at intervals along the axial direction of the body, and the at least one second pressure measuring unit is close to the far end of the body compared with the first pressure measuring unit.

Preferably, the first load cell and the second load cell each include a sensing part for measuring a pressure value and a wire connecting the sensing part and the processor.

Preferably, the sensing component comprises a flexible pressure sensor comprising a dielectric layer and first and second conductive layers disposed on opposite sides of the dielectric layer.

Preferably, the sensing component comprises a flexible pressure sensor comprising a first flexible substrate and a second flexible substrate arranged in a stack;

the first flexible substrate comprises a first flexible substrate and microstructures arranged on one surface of the first flexible substrate and having at least two heights, and a conductive layer is arranged on the surface of the first flexible substrate with the microstructures;

the second flexible substrate comprises a second flexible substrate and an electrode arranged on one surface of the second flexible substrate, and the electrode is in contact with part of the conductive layer.

Preferably, the number of the at least one second load cell is one, and the axial distance between the first load cell and the second load cell along the body is 4-12 cm.

Preferably, the number of the at least one second load cell is one, and the axial distance between the first load cell and the second load cell along the body is 12-20 cm.

Preferably, projections of the first load cell and the at least one second load cell on a cross section perpendicular to the axial direction of the body are arranged at intervals in the circumferential direction of the outer circumferential wall of the body.

Preferably, the number of the at least one second load cell is multiple, and the axial distance between two adjacent second load cells along the body is 0.8-2.5 cm.

Preferably, the body comprises a first section and a second section from the far end to the near end in sequence, the first section is axially communicated with the second section, and the pipe diameter of the first section is gradually reduced from the connecting end connected with the second section to the free end far away from the second section.

Preferably, the load cell assembly is provided on the outer peripheral wall of the second section.

Preferably, the second section is of constant diameter construction.

Preferably, the pressure measurement pipe further comprises a mounting assembly, the mounting assembly comprises a base, the base surrounds at least part of the peripheral wall, grooves are formed in the base, and the first pressure measuring unit and the second pressure measuring unit are respectively fixed in the corresponding grooves.

Preferably, the first and second load cells are integrally attached to the inner surfaces of the recess, respectively.

Preferably, the first load cell and the second load cell are respectively attached to the inner surface of the recess by an adhesive, and the adhesive fills a gap between the first load cell and the inner surface of the recess and a gap between the second load cell and the inner surface of the recess.

Preferably, the base has a hardness greater than the first load cell and the second load cell and less than the body.

Preferably, the base surrounds at least one third of the peripheral wall.

Preferably, the contour line of the inner surface of the base, which is perpendicular to the axial direction, is arc-shaped, and the inner surface of the base is attached to the peripheral wall.

Preferably, the base is made of a high polymer material, and the base is fixed on the peripheral wall in an adhesion or hot melting mode; alternatively, the first and second electrodes may be,

the base is made of metal and is fixed on the peripheral wall in a bonding mode.

The utility model also provides an intravascular pressure gradient sensing system, include:

any of the pressure measurement conduits described above; and

a processor electrically connected to the first load cell and the at least one second load cell of the pressure measurement catheter, respectively, the processor configured to receive the proximal vascular pressure measured by the first load cell and the distal vascular pressure measured by the at least one second load cell, respectively, and determine at least one fractional flow reserve based on the proximal vascular pressure and the at least one distal vascular pressure.

The embodiment of the utility model provides an above-mentioned technical scheme compares with prior art has following advantage: the utility model discloses a pressure measurement pipe is through setting up first pressure cell and second pressure cell, can once the simultaneous measurement obtain distal end vascular pressure Pd and near-end vascular pressure Pa, and the pressure value that will survey transmits to the treater, calculates the ratio between them and can obtain coronary artery blood flow reserve fraction FFR. The pressure measurement catheter reduces the operation time and the plaque risk caused by the back-and-forth operation of the guide wire in and out in operation, reduces the FFR value deviation caused by extra resistance caused by the blood vessel restoring curvature after the guide wire is withdrawn, and improves the measurement accuracy. Meanwhile, the simplified operation flow reduces the times of repeatedly passing in and out the blood vessel by guide wires and other instruments, is convenient for the operation of operators, reduces the risk of patients and also reduces the FFR detection cost.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description, serve to explain the principles of the invention.

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without inventive labor.

In the drawings:

fig. 1 is a schematic structural view of an intravascular pressure gradient sensing system according to a first embodiment of the present invention;

FIG. 2 is a partial cross-sectional view of the pressure measuring catheter of FIG. 1;

FIG. 3 is a schematic view of a portion of the pressure measurement catheter of FIG. 1;

FIG. 4 is a schematic view of the pressure measurement catheter of FIG. 1 entering an intravascular test pressure;

fig. 5 is a partial structural schematic view of a pressure measurement catheter according to a first embodiment of the present invention;

FIG. 6 is a top view of FIG. 5;

FIG. 7 is an axial cross-sectional view of FIG. 5;

FIG. 8 is a radial cross-sectional view of a pressure measurement catheter in accordance with an embodiment of the first embodiment of the present invention;

FIG. 9 is a radial cross-sectional view of the pressure measurement conduit of a preferred embodiment of FIG. 8;

fig. 10 is an example axial cross-sectional view of a pressure measurement catheter of a first embodiment of the present invention;

fig. 11 is another example axial cross-sectional view of a pressure measurement catheter of the first embodiment of the present invention;

fig. 12 is an axial partial structural view of a pressure measurement catheter according to a second embodiment of the present invention;

FIG. 13 is a schematic view of a radial partial structure of the pressure measurement catheter of FIG. 12;

fig. 14 is another axial partial structural schematic view of a pressure measurement catheter in accordance with a second embodiment of the present invention;

FIG. 15 is a schematic view of a radial partial structure of the pressure measurement catheter of FIG. 14;

fig. 16 is a schematic view showing the measurement result of a pressure measuring catheter according to a second embodiment of the present invention;

fig. 17 is a schematic view of another measurement result of the pressure measurement catheter according to the second embodiment of the present invention.

Detailed Description

In order to clearly understand the technical features, objects, and effects of the present invention, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, it should be understood that the directions or positional relationships indicated by "front", "back", "upper", "lower", "left", "right", "longitudinal", "horizontal", "vertical", "horizontal", "top", "bottom", "inner", "outer", "head", "tail", etc. are configured and operated in specific directions based on the directions or positional relationships shown in the drawings, and are only for convenience of describing the present invention, but do not indicate that the device or element referred to must have a specific direction, and thus, should not be construed as limiting the present invention.

It is also noted that, unless expressly stated or limited otherwise, the terms "mounted," "connected," "secured," "disposed," and the like are intended to be inclusive and mean, for example, that they may be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. When an element is referred to as being "on" or "under" another element, it can be "directly" or "indirectly" on the other element or intervening elements may also be present. The terms "first", "second", "third", etc. are only for convenience in describing the present technical solution, and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated, whereby the features defined as "first", "second", "third", etc. may explicitly or implicitly include one or more of such features. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

In the description of the present invention, it should be noted that, in the field of interventional medical devices, the proximal end refers to the end closer to the operator, and the distal end refers to the end farther from the operator; axial refers to a direction parallel to the line connecting the center of the distal end and the center of the proximal end of the medical device, and radial is perpendicular to the axial direction. The foregoing definitions are for convenience only and are not to be construed as limiting the present invention.

Referring to fig. 1-4, the present invention provides an intravascular pressure gradient sensing system 1 that includes a pressure measurement catheter 10 and a processor 20. Therein, a pressure measuring catheter 10 is used to enter a blood vessel to simultaneously measure a proximal blood vessel pressure Pa and a distal blood vessel pressure Pd. A processor 20 is electrically connected to the pressure measurement catheter 10 for receiving the proximal vascular pressure Pa and the distal vascular pressure Pd measured by the pressure measurement catheter 10 and determining a fractional flow reserve FFR based on the proximal vascular pressure Pa and the distal vascular pressure Pd. Specifically, by calculating the ratio Pd/Pa between the distal blood vessel pressure Pd and the proximal blood vessel pressure Pa, the fractional flow reserve FFR of the coronary artery vessel can be rapidly and accurately determined before, during and/or after the percutaneous coronary intervention.

The intravascular pressure gradient sensing system 1 may include a display 30, the display 30 being coupled to the processor 20. The display 30 is used to instantaneously display the measured Pd and Pa values and the FFR value obtained by the processor 20 from the Pd and Pa values. The processor 20 and the display 30 may be integrated to form a processing device. Processor 20 may employ any suitable means known in the art capable of obtaining Pd and Pa values and obtaining FFR values based on such calculations, and will not be described in detail herein.

The pressure measuring catheter 10 comprises a pressure measuring assembly 12 and a body 11 in the form of a tube. Wherein the body 11 extends in an axial direction C between a proximal end and a distal end. The load cell assembly 12 includes a first load cell 121 and at least one second load cell 122, and the first load cell 121 and the at least one second load cell 122 are provided on the outer circumferential wall 110 of the body 11 and are arranged at intervals in the axial direction C of the body 11. The at least one second load cell 122 is closer to the distal end of the body 11 than the first load cell 121. Thus, the first pressure measurement unit 121 may measure the intravascular proximal vascular pressure Pa and the second pressure measurement unit 122 may measure the intravascular distal vascular pressure Pd. The processor 20 is electrically connected to the first load cell 121 and the at least one second load cell 122, respectively. The processor 20 is configured to receive the proximal vascular pressure Pa measured by the first pressure measurement unit 121 and the distal vascular pressure Pd measured by the at least one second pressure measurement unit 122, respectively, and determine at least one fractional flow reserve FFR based on the proximal vascular pressure Pa and the at least one distal vascular pressure Pd.

The utility model discloses a pressure measurement pipe 10 is through setting up first pressure cell 121 and second pressure cell 122, can once measure simultaneously and obtain distal end vascular pressure Pd and near-end vascular pressure Pa, and the pressure value Pd and the Pa that will survey transmit to treater 20, calculates ratio between them and can obtain coronary artery blood flow reserve fraction FFR. The pressure measurement catheter 10 reduces the operation time and the plaque risk caused by the back-and-forth operation of the guide wire 4 in and out during the operation, reduces the FFR value deviation caused by extra resistance caused by the blood vessel restoring curvature after the guide wire 4 is withdrawn, and improves the measurement accuracy. Meanwhile, the simplified operation flow reduces the times of repeatedly passing in and out the blood vessel by guide wires and other instruments, is convenient for the operation of operators, reduces the risk of patients and also reduces the FFR detection cost.

Specifically, the main body 11 is used for passing a guide wire 4 for percutaneous coronary intervention, and the pressure measuring unit 12 provided on the main body 11 can perform FFR detection during percutaneous coronary intervention. The operator can freely select a proper guide wire 4 according to coronary artery lesion to pass through the body 11, the body 11 can also provide the guide wire 4 with extra support, the lesion is passed through in the help, the times of repeatedly passing in and out the blood vessel of the guide wire 4 and other instruments are reduced, the operator operation is convenient, the risk of the patient is reduced, the consumable expense of guiding the catheter and the guide wire 4 is also reduced, the FFR detection cost is reduced, and the economic burden of the patient is reduced.

Moreover, the measurement mode of the pressure measurement catheter 10 can replace the mode that the traditional FFR uses the pressure at the external guide catheter port hemostatic valve as the Pa value, and compared with the Pa measurement point of the traditional FFR, the Pa measurement point is greatly close to the coronary artery opening, is closer to the pressure point defined by the original FFR, and has higher accuracy.

Further, the utility model discloses a pressure measurement pipe 10 can also reduce the drift of the Pa value that brings when instrument operations such as guide catheter and hemostasis valve and injection contrast medium, and the FFR value is more stable, also reduces the risk that needs to mark Pa again because of various operations. The pressure measurement catheter 10 does not need to be withdrawn in operation, and the second pressure measurement unit 122 can be arranged to directly form a real-time FFR map and accurately indicate the position and the length of the intravascular lesion. Since the pressure measurement catheter 10 employs the first pressure cell 121 and the second pressure cell 122, zero adjustment is not required before the pressure measurement catheter 10 is used; meanwhile, in the measuring process, due to the convenient operation and short time, the use of the contrast agent can be reduced.

The pressure measuring catheter 10 of the present invention, the load cell assembly 12 includes a first load cell 121 and at least one second load cell 122. That is, the load cell assembly 12 may include one first load cell 121 and one second load cell 122, or the load cell assembly 12 may include one first load cell 121 and a plurality of second load cells 122. Referring to fig. 1 to 11, in the pressure measuring tube 10 according to the first embodiment of the present invention, the load cell assembly 12 includes a first load cell 121 and a second load cell 122. The pressure measurement catheter 10 will be described in detail below by taking a first embodiment as an example.

In a specific embodiment of this embodiment, the body 11 includes a first section 111 and a second section 112 in order from the distal end to the proximal end. The first section 111 may have a length of 3-6mm, preferably 5mm, a distal end being a free end and a proximal end being connected to the second section 112. The diameter of the first section 111 is gradually reduced from the connecting end connected with the second section 112 to the free end far away from the second section 112, and the reducing structure is beneficial to improving the conveying performance and the passing performance of the body 11. The first section 111 is used as the front end of the pressure measuring catheter 10 entering the blood vessel, and is made softer by adopting a reducing structure, so that the injury to the blood vessel can be reduced when the pressure measuring catheter advances in the blood vessel.

Referring to fig. 2 and 4, the first section 111 has an inner cavity 1112 defined by an outer peripheral wall 1111, which may be a nylon layer 1111. Further, at least a portion of the outer peripheral wall 1111 of the first segment 111 is provided with a hydrophilic coating 1113 to reduce friction when the body 11 enters and exits the blood vessel a, so that the body 11 can pass through the lesion b more conveniently, thereby enhancing operability and reducing patient risk. The hydrophilic coating 1113 may be a medical grade water soluble biopolymer, such as an isocyanate compound. Preferably, the hydrophilic coating 1113 is applied to the surface of the peripheral wall 1111 of the first section 111.

The second section 112 also has an inner cavity 112b defined by the outer peripheral wall 112a, the inner cavity 112b communicating with the inner cavity 1112 of the first section 111 such that the first section 111 communicates axially with the second section 112. The outer peripheral wall 112a of the second section 112 may be of a multi-layered construction, e.g., radially outward from the inner cavity 112b, and the outer peripheral wall 112a may include, in order, an inner nylon layer 1123, a woven layer 1122, and an outer nylon layer 1121. The braid 1122 may be braided from wire. Further, at least a part of the inner surface of the second section 112 is provided with a hydrophilic coating 1124 to reduce the friction between the inner cavity of the body 11 and the puncture guide wire when the body 11 enters the blood vessel along the puncture guide wire, so as to increase the passability of the body 11. Preferably, the inner diameter of the second section 112 is equal throughout the axial direction, i.e., the second section 112 has a constant diameter structure, which facilitates its use as an operating handle. The outer peripheral wall 110 of the body 11 includes an outer peripheral wall 1111 of the first stage 111 and an outer peripheral wall 112a of the second stage 112.

In this embodiment, the load cell assembly 12 includes a first load cell 121 and a second load cell 122, and the load cell assembly 12 is disposed on the outer peripheral wall 112a of the second section 112, that is, the first load cell 121 and the second load cell 122 are both disposed on the outer peripheral wall 112a of the second section 112, so as to avoid being disposed on the softer first section 111, and to prevent the load cell assembly 12 from affecting the operability of the body 11. In the case of the pressure measuring catheter 10 for coronary vessels, the axial spacing L between the first pressure cell 121 and the second pressure cell 122 along the body 11 may be 4-12cm, preferably 6-10 cm. In the case of the pressure measuring catheter 10 for peripheral blood vessels, the axial spacing L between the first pressure cell 121 and the second pressure cell 122 along the body 11 may be 12-20cm, preferably 20 cm.

In a specific embodiment, the projections of the first load cell 121 and the second load cell 122 on the cross section (radial surface) perpendicular to the axial direction of the body 11 are arranged at intervals along the circumferential direction of the outer circumferential wall 110 of the body 11, that is, the first load cell 121 and the second load cell 122 are not on the same axis, for example, located at two ends of the same radial direction. Of course, the above is only one embodiment of the present embodiment, and is not a limitation of the present invention, and in other embodiments, the first pressure measuring unit 121 and the second pressure measuring unit 122 may be on the same axis.

To facilitate the intraoperative operation, the pressure measurement catheter 10 further comprises a visualization assembly 13, and the visualization assembly 13 may comprise a plurality of visualization rings, for example, four visualization rings 131 may be included, wherein two visualization rings 131 are respectively disposed on two axial sides of the first pressure cell 121, and the other two visualization rings 131 are respectively disposed on two axial sides of the second pressure cell 122, so as to determine the positions of the first pressure cell 121 and the second pressure cell 122 in the blood vessel by X-ray.

Referring to fig. 4, in the pressure measurement process entering the blood vessel a, the guide wire 4 for percutaneous coronary intervention passes through the body 11 of the pressure measurement catheter 10, and the first pressure measurement unit 121 is arranged on the proximal side of the second section 112, and is used for obtaining the average pressure of the aorta at the mouth of the coronary artery, namely the proximal blood vessel pressure Pa; a second pressure cell 122 is on the second segment 112 near the distal side for obtaining the pressure at the distal end of the lesion, i.e., the distal vessel pressure Pd.

Referring to fig. 5-7, the pressure measurement conduit 10 further includes a mounting assembly that includes a base 141. The base 141 is used for mounting the first load cell 121 and the second load cell 122, so that the influence of the load cell assembly 12 on the flexibility and the controllability of the body 11 can be reduced, and the connection strength between the load cell assembly 12 and the body 11 can be improved. The base 141 surrounds at least a portion of the peripheral wall 110 of the body 11. Grooves 1411 are formed in the base 141, and the first and

second load cells

121 and 122 are respectively fixed in the corresponding grooves 1411.

For example, the first load cell 121 is disposed in the pocket 1411 of one pedestal 141, and the second load cell 122 is disposed in the pocket 1411 of the other pedestal 141. The structure of the base 141 is only used as an example and is not a limitation of the present invention, and the structure of other mounting assemblies configured based on the concept of the present invention is within the protection scope of the present invention, for example, a base 141 can be further configured, the base 141 includes a plurality of grooves 1411, the first pressure measuring unit 121 and the second pressure measuring unit 122 are respectively fixed in the corresponding grooves 1411, and there is no further enumeration here.

The recessed groove 1411 may be a recessed area formed by recessing the base 141, and the recessed shape of the recessed groove 1411 may be a rectangular parallelepiped or a column, so as to fix the first load cell 121 or the second load cell 122 mainly. The inner surface of the pocket 1411 includes a bottom surface and a side surface surrounding the bottom surface, and the first and

second load cells

121 and 122 are integrally attached to the inner surface of the pocket 1411, respectively, and may be specifically attached to the bottom surface of the pocket 1411. It should be understood that the integral attachment herein means that the first load cell 121 and the second load cell 122 are completely attached to the inner surface (e.g., the bottom surface) of the pocket 1411, respectively, with no gap or space therebetween.

Specifically, the first pressure measuring unit 121 further includes a sensing part 12a for measuring a pressure value, and a wire 12b for electrically connecting the sensing part 12a and the processor 20. Likewise, the second pressure measuring unit 122 further includes a sensing part 12a for measuring a pressure value, and a wire 12b for electrically connecting the sensing part 12a and the processor 20. To ensure the consistency of the measurement and the effectiveness of the pressure ratio, the sensing unit 12a of the first load cell 121 is identical to the sensing unit 12a of the second load cell 122, and of course, the structure of the lead 12b is also identical, so that the sensing unit 12a and the lead 12b in the following do not distinguish the first load cell 121 from the second load cell 122, which is applicable to both the first load cell 121 and the second load cell 122.

The sensing component 12a is used to acquire intravascular blood flow pressure, i.e., to acquire Pd or Pa. The sensing part 12a may be made of a semiconductor silicon material, and preferably includes a developing portion made of platinum or the like for indicating the position of the sensing part 12a under X-rays. One end of the wire 12b is connected to the sensing member 12a, and the other end is connected to the processor 20 and the display 30, or connected to the processor 20, so as to transmit the pressure signal (Pd or Pa value) sensed by the sensing member 12 a. The processor 20 calculates the pressure signal sensed by the sensing part 12a to obtain the FFR value, and displays the result on the display 30.

The first pressure measuring unit 121 and the second pressure measuring unit 122 are integrally attached to the inner surface of the recess 1411, and specifically, the sensing parts 12a of the first pressure measuring unit 121 and the second pressure measuring unit 122 are integrally attached to the inner surface of the corresponding recess 1411. The lead wire 12b is embedded in the wall of the body 11 and extends to the proximal end of the body 11. Specifically, the lead 12b is attached to the outer peripheral wall 112a of the second segment 112 and extends axially, and the outer nylon layer 1121 wraps the sensing component 12a and the lead 12b to fix the sensing component 12a and the lead 12b relative to the body 11.

In one embodiment of the present invention, the hardness of the base 141 is greater than the hardness of the first load cell 121 and the hardness of the second load cell 122 and less than the hardness of the body 11. For example, the base 141 may be made of a metal material with a relatively high hardness, such as stainless steel, or may be made of a polymer material, such as polyamide, polyether amide, polyether ether ketone, polyimide, polyethylene, polytetrafluoroethylene, or the like. The sensing part 12a may employ a flexible pressure sensor, which means that an organic/inorganic material electronic device is fabricated on a flexible/ductile substrate using a flexible electronic technology. Of course, the sensing component 12a may also be a non-flexible pressure sensor, and it is only necessary to ensure that the hardness of the sensing component 12a is less than that of the base 141. The outer peripheral wall 112a of the second section 112 of the body 11 has a multi-layer structure, and the middle layer is a metal wire braided reinforcing layer, so that the hardness of the body 11 is greater than that of the base 141. The relative hardness setting of above-mentioned three can reduce the external diameter that brings because of sensing component 12a increases and the operation risk that brings outstanding body 11 surface, has improved the pliability and the bending resistance of body 11, has promoted the vascular compliance and the operational safety of body 11, has reduced the operation degree of difficulty.

In one embodiment, a flexible pressure sensor includes a dielectric layer and first and second conductive layers disposed on opposite sides of the dielectric layer. Specifically, the medium layer may include a base layer and a plurality of pores distributed in the base layer, the pores are communicated with the outside so that air in the pores can be discharged and sucked, and a piezoelectric thin film layer is further attached to the pore walls of the pores. On one hand, at least part of the pore channels in the plurality of pore channels distributed in the matrix layer penetrate through the matrix layer, and the rest pore channels are communicated with the part of pore channels, so that air in all the pore channels can be circularly discharged and sucked under the action of pressure. Therefore, under the action of pressure, the sensor has the function of changing capacitance by exhausting and sucking air, and the detection sensitivity is improved. On the other hand, a piezoelectric film layer is also attached to the hole wall of the pore passage, and the piezoelectric film layer has a piezoelectric effect, namely the dielectric constant of the piezoelectric film layer is changed under the action of pressure. Therefore, under the action of pressure, the piezoelectric film layer can change the area and the thickness of the sensor, and can also change the dielectric constant of the dielectric layer, so that the detection sensitivity of the sensor is improved.

In other embodiments, the dielectric layer includes a matrix layer and composite piezoelectric particles distributed in the matrix layer, and the composite piezoelectric particles include inorganic piezoelectric particles and a dopamine layer coated on the surfaces of the inorganic piezoelectric particles. Dopamine contains a large number of groups such as hydrogen bonds, hydroxyl groups and the like, and can be well combined with inorganic materials and organic materials. Therefore, dopamine can be well combined with inorganic piezoelectric particles to form composite piezoelectric particles with a core-shell structure, and then the dispersibility of the composite piezoelectric particles in a matrix layer and the binding force of the composite piezoelectric particles with the matrix layer are improved. Therefore, the composite piezoelectric particles can be well dispersed in the matrix layer, the interface polarization can be reduced, the dielectric property of the dielectric layer is improved, and the detection sensitivity of the flexible pressure sensor is further improved. The compound piezoelectric particles form a bulge on the surface of the dielectric layer, at the moment, because of the existence of the dopamine layer in the compound piezoelectric particles, the binding force of the dielectric layer and the first electrode layer and the second electrode layer can be greatly increased, the reliability of the binding force between the dielectric layer and the first electrode layer and the second electrode layer is improved, and the service life and the test accuracy of the flexible pressure sensor are ensured.

In another particular embodiment, a flexible pressure sensor includes a first flexible substrate and a second flexible substrate arranged in a stack. The first flexible substrate comprises a first flexible substrate and microstructures arranged on one surface of the first flexible substrate and having at least two heights, and a conductive layer is arranged on the surface of the first flexible substrate, which is provided with the microstructures. The second flexible substrate comprises a second flexible substrate and an electrode arranged on one surface of the second flexible substrate, and the electrode is in contact with part of the conductive layer. Under the action of pressure, the first-level microstructure with the highest height deforms firstly, so that the contact area between the conductive layer and the electrode is increased, the conductive paths of the sensor are increased, the sensitivity curve is linear, and the sensitivity is high. Along with the increase of the pressure, the second-level microstructure, the third-level microstructure and the like which are next to each other in height are sequentially contacted with the electrodes, so that the conductive path of the sensor is further increased, and the sensitivity of the sensor is kept. Therefore, the saturation contact area of the sensor can be increased through the multi-level microstructure, the conductive paths are increased, the pressure linear response range of the sensor is prolonged, and the sensitivity of the sensor is improved while the detection range and the reliability are improved.

In the case where the sensing member 12a is a flexible pressure sensor, the flexible pressure sensor having sufficient flexibility may be directly wrapped around the outer circumferential wall 110 of the body 11; of course, the flexible pressure sensor may also be fixed in the groove 1411 of the base 141. For the neuro-interventional procedure, the pressure measuring catheter 10 in which the sensing component 12a employs a flexible pressure sensor is more suitable.

In order to further enhance the attachment performance of the sensing part 12a to the inner surface of the pocket 1411, the first and

second load cells

121 and 122 may be respectively attached to the inner surface of the pocket 1411 by the adhesive 142, the adhesive 142 filling a gap between the first load cell 121 and the inner surface of the pocket 1411, and likewise, the adhesive 142 may fill a gap between the second load cell 122 and the inner surface of the pocket 1411. Of course, in other embodiments, the first and

second load cells

121 and 122 may be directly disposed in the recess 1411 by other fixing means, so that the sensing part 12a is attached to the inner surface of the recess 1411.

Referring to fig. 8-11, in one embodiment of the present embodiment, the base 141 of the pressure measuring catheter 10 surrounds at least one third of the outer peripheral wall 110 of the packaging body 11. The inner surface 141a of the base 141 is in contact with the outer peripheral wall 110 of the body 11, and in the case where the outer peripheral wall 110 of the body 11 is arc-shaped, the inner surface 141a of the base 141 is arc-shaped to be in contact therewith, that is, the contour line of the inner surface 141a in the direction perpendicular to the axial direction of the body 11 is arc-shaped. Of course, the outer surface 141b of the base 141 may also be curved.

The base 141 is arranged at least one third of the peripheral wall 110 surrounding the wrapping body 11, so that the connection strength can be improved, the reliability of the pressure measurement catheter 10 in the blood vessel pressure measurement process is improved, and the pressure measurement catheter is prevented from falling off due to bending stress when the blood vessel is bent. On the basis of ensuring that the base 141 is reliably connected with the body 11, the arrangement of the pressure measuring unit does not influence the body 11.

Referring to fig. 9, in a preferred embodiment, the base 141 surrounds and wraps the entire peripheral wall 110 of the body 11, that is, the base 141 is sleeved on the peripheral wall 110 of the body 11, so that the bending consistency of the base 141 and the body 11 is further enhanced on the basis of improving the connection strength, and the overall flexibility of the pressure measurement conduit 10 is ensured.

Referring to fig. 10, in the case that the base 141 is made of a polymer material, the base 141 may be fixed to the outer circumferential wall 110 by bonding or heat-melting, and the two are integrated. Referring to fig. 11, in the case where the base 141 is made of metal, the base 141 is fixed to the outer circumferential wall 110 by means of adhesion, and an adhesive 143 for adhesion is interposed between the base 141 and the outer circumferential wall 110 of the body 11.

Referring to fig. 12 to 15, the difference from the first embodiment is that in the pressure measuring tube 10 according to the second embodiment of the present invention, the pressure measuring unit 12 includes a first pressure measuring cell 121 and a plurality of second pressure measuring cells 122. The number of the second load cells 122 may be two to ten, and preferably six to ten. The axial distance between two adjacent second pressure measuring units 122 along the body 11 is 0.8-2.5 cm. Projections of the one first load cell 121 and the plurality of second load cells 122 on a cross section (radial plane) perpendicular to the axial direction of the body may be arranged at intervals in the circumferential direction of the outer circumferential wall 110 of the body 11, that is, the one first load cell 121 and the plurality of second load cells 122 are not on the same axis. Of course, in other embodiments, the first load cell 121 may be on the same axis as the at least one second load cell 122; or the plurality of second load cells 122 are on the same axis, and the first load cell 121 and the plurality of second load cells 122 are not on the same axis.

Referring to fig. 16, a plurality of Pd values may be measured by using the plurality of second pressure measuring cells 122, and the plurality of Pd values may be compared with the Pa value measured by the first pressure measuring cell 121 to obtain a plurality of FFR values, so that the influence of the operation of the body 11 itself and the hemodynamics on the FFR measurement result may be reduced to the maximum extent. Obtaining multiple FFR values at the same time allows the FFR distribution in the vessel to be known at the same time, and the FFR distribution in the vessel can be obtained without the need to perform a pull-back operation of the pressure measurement catheter 50. In the example of fig. 16, measurement point position 1 indicates the position of the blood vessel where the first pressure cell 121 is located, and measurement point positions 2 to 7 indicate the positions of the blood vessels where the six second pressure cells 122 are located. The FFR distribution at different positions in the blood vessel at the same time can be known from the graph.

Further, referring to fig. 17, a plurality of Pd can be measured by the plurality of second pressure measuring units 122, and two adjacent Pd values are compared, and the Pd value changes the most, that is, the mutation point, corresponds to the most severe stenosis portion. In the example of fig. 17, measurement point position 1 indicates the position of the blood vessel where the first pressure cell 121 is located, and measurement point positions 2 to 7 indicate the positions of the blood vessels where the six second pressure cells 122 are located. The pressure value P of each measuring point position can be obtained from the curve in the graph; from the histogram in the figure, the difference Δ P between two adjacent Pd values can be found, for example, the height of the bar at station position 4 represents the difference Δ P between the pressure value at station position 3 minus the pressure value at station position 4. As can be seen from the figure, the difference value delta P of the measuring point position 4 is the maximum, namely the section of the blood vessel from the measuring point position 3 to the measuring point position 4 is a mutation part and is the most serious part of stenosis.

In the example of fig. 12 and 13, the load cell assembly 12 includes six second load cells 122, and the six second load cells 122 are arranged at even intervals in the axial direction along the direction away from the first load cell 121, that is, two adjacent second load cells 122 are not located on the same radial plane, and the axial interval H between two adjacent second load cells 122 is 1.5-2.5cm, preferably 2 cm. The six second pressure measuring units 122 and the one first pressure measuring unit 121 may be uniformly arranged at intervals in the circumferential direction and the axial direction, that is, the six second pressure measuring units 122 and the one first pressure measuring unit 121 are not located on the same axis, but are arranged at uniform intervals in the circumferential direction and at uniform intervals in the axial direction in projection. The axial spacing H between adjacent first and

second load cells

121, 122 may also be 1.5-2.5cm, preferably 2 cm.

In the example of fig. 14 and 15, the load cell assembly 12 includes ten second load cells 122, the ten second load cells 122 are arranged at even intervals in the axial direction in the direction away from the first load cell 121, that is, two adjacent second load cells 122 are not located on the same radial plane, and the axial interval h between two adjacent second load cells 122 is 0.8-1.2cm, preferably 1 cm. The ten second pressure measuring units 122 and the one first pressure measuring unit 121 may be uniformly arranged at intervals in the circumferential direction and the axial direction, and the ten second pressure measuring units 122 and the one first pressure measuring unit 121 are not located on the same axis, but are arranged at uniform intervals in the circumferential direction and at uniform intervals in the axial direction in projection. The axial spacing h between adjacent first and

second load cells

121, 122 may also be 0.8-1.2cm, preferably 1 cm.

It should be understood that the above embodiments of six and ten second pressure measuring units 122 are only used as examples and are not intended to limit the present invention, and those skilled in the art can select an appropriate number of second pressure measuring units as needed, and the detailed description is omitted here.

It is to be understood that the foregoing examples merely represent preferred embodiments of the present invention, and that the description thereof is more specific and detailed, but not intended to limit the scope of the invention; it should be noted that, for those skilled in the art, the above technical features can be freely combined, and several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention; therefore, all changes and modifications that come within the meaning and range of equivalency of the claims are to be embraced within their scope.

Claims

1. A pressure measurement catheter, comprising:

a body in the shape of a tube extending axially between a proximal end and a distal end; and

the pressure measuring assembly comprises a first pressure measuring unit and at least one second pressure measuring unit, the first pressure measuring unit and the at least one second pressure measuring unit are arranged on the peripheral wall of the body and along the axial direction of the body at intervals, and the at least one second pressure measuring unit is closer to the far end of the body.

2. The pressure measurement catheter of claim 1, wherein the first and second load cells each include a sensing component for measuring a pressure value and a lead connecting the sensing component and a processor.

3. The pressure measurement catheter of claim 2, wherein the sensing component comprises a flexible pressure sensor comprising a dielectric layer and first and second conductive layers disposed on opposite sides of the dielectric layer.

4. The pressure measurement catheter of claim 2, wherein the sensing component comprises a flexible pressure sensor comprising a first flexible substrate and a second flexible substrate arranged in a stack,

the first flexible substrate comprises a first flexible substrate and microstructures arranged on one surface of the first flexible substrate and having at least two heights, and a conductive layer is arranged on the surface of the first flexible substrate, which is provided with the microstructures;

5. The pressure measurement catheter of claim 1, wherein the at least one second load cell is one in number, and the axial distance between the first load cell and the second load cell along the body is 4-12 cm.

6. The pressure measurement catheter of claim 1, wherein the at least one second load cell is one in number, and the axial distance between the first load cell and the second load cell along the body is 12-20 cm.

7. The pressure measurement catheter according to claim 1, wherein projections of the first load cell and the at least one second load cell on a cross section perpendicular to the axial direction of the body are arranged at intervals in a circumferential direction of the outer circumferential wall of the body.

8. The pressure measuring catheter according to claim 1, wherein the at least one second pressure measuring unit is provided in plurality, and the axial distance between two adjacent second pressure measuring units along the body is 0.8-2.5 cm.

9. The pressure measurement catheter of claim 1, wherein the body comprises a first section and a second section in sequence from the distal end to the proximal end, the first section being in axial communication with the second section, the first section having a diameter that tapers from a connection end connected to the second section to a free end distal from the second section.

10. The pressure measurement catheter of claim 9, wherein the load cell assembly is disposed on the peripheral wall of the second section.

11. The pressure measurement catheter of claim 9, wherein the second section is of constant diameter construction.

12. The pressure measurement catheter of any one of claims 1-11, further comprising a mounting assembly, the mounting assembly including a base surrounding at least a portion of the peripheral wall, the base having a recess, the first load cell and the second load cell being secured in the respective recesses.

13. The pressure measurement catheter of claim 12, wherein the first and second load cells are each integrally affixed to an inner surface of the recess.

14. The pressure measurement catheter of claim 13, wherein the first load cell and the second load cell are each attached to the inner surface of the recess by an adhesive that fills a space between the first load cell and the inner surface of the recess and a space between the second load cell and the inner surface of the recess.

15. The pressure measurement catheter of claim 12, wherein the base has a stiffness greater than a stiffness of the first load cell and a stiffness of the second load cell and less than a stiffness of the body.

16. The pressure measurement catheter of claim 12, wherein the base is wrapped around at least one third of the peripheral wall.

17. The pressure measurement catheter of claim 12, wherein a contour of the inner surface of the base perpendicular to the axial direction is arcuate, the inner surface of the base conforming to the peripheral wall.

18. The pressure measuring catheter according to claim 12, wherein the base is made of a polymer material, and the base is fixed to the outer circumferential wall by means of adhesion or heat fusion; alternatively, the first and second electrodes may be,

the base is made by metal, the base is fixed in through the mode that bonds on the periphery wall.

19. An intravascular pressure gradient sensing system, comprising:

the pressure measurement catheter of any one of claims 1-18; and

a processor electrically connected to the first pressure cell and the at least one second pressure cell of the pressure measurement catheter, respectively, the processor configured to receive the proximal vascular pressure measured by the first pressure cell and the distal vascular pressure measured by the at least one second pressure cell, respectively, and determine at least one fractional flow reserve based on the proximal vascular pressure and the at least one distal vascular pressure.