Counter-pulsation balloon catheter and counter-pulsation balloon catheter system

Abstract

The invention provides a counterpulsation balloon catheter and a counterpulsation balloon catheter system. The counterpulsation balloon catheter comprises a balloon and a catheter body. The balloon is communicated with the catheter and is configured to be expanded or contracted by filling or extracting the filling liquid through the catheter; the catheter wall of the catheter comprises an inner layer, a braid layer and an outer layer. The braid layer comprises a first-direction wire and a second-direction wire which are arranged in a winding mode and inclined to the axis of the catheter, the winding directions of the first-direction wire and the second-direction wire are opposite, and the first-direction wire and the second-direction wire intersect to form a plurality of intersection points; wherein the first-direction wires and the second-direction wires are flat wires, the thickness directions of the first-direction wires and the second-direction wires extend in the radial direction of the catheter, and the ratio of the width to the thickness of the flat wires ranges from 2: 1 to 4: 1; the catheter comprises a main body section in the axial direction, in the main body section, a first weaving angle formed by the first direction wire and the axis of the catheter is 30-60 degrees, and a second weaving angle formed by the second direction wire and the axis of the catheter is 30-60 degrees. Not only is the pushing performance of the catheter improved, but also the collapse resistance of the catheter cavity is enhanced.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and particularly to an anti - pulsation balloon catheter and an anti - pulsation balloon catheter system. Background Art

[0002] The balloon counterpulsation device is an important tool for improving the hemodynamic state of patients and is widely used in the interventional treatment of cardiovascular diseases. Currently, the balloon counterpulsation device usually uses gas (such as helium, etc.) as the filling medium for the balloon. However, using gas as the filling medium faces the following problems in clinical practice: 1. There are significant safety hazards in gas filling: When the balloon ruptures due to over - filling or material aging, the gas will quickly enter the human vascular system. Since the gas cannot be quickly absorbed and metabolized by the human body, after the gas enters the blood vessels, the emergency treatment is difficult. Traditional drainage or dredging methods usually cannot quickly remove it, which may cause serious consequences, may lead to serious gas embolism, and even endanger life.

[0003] 2. The intraoperative monitoring is relatively complex: The leakage of gas is difficult to detect and locate in a timely manner, increasing the uncertainty of intraoperative operation. Summary of the Invention

[0004] The purpose of the present invention is to provide an anti - pulsation balloon catheter and an anti - pulsation balloon catheter system to solve the safety problems existing in the existing balloon counterpulsation device using gas as the filling medium.

[0005] To solve the above - mentioned technical problems, the present invention provides an anti - pulsation balloon catheter, which includes a balloon and a catheter; the balloon is in communication with the catheter and is configured to be inflated or deflated by filling or extracting a filling liquid through the catheter to achieve expansion or contraction; The tube wall of the catheter includes an inner layer, a braided layer, and an outer layer; the braided layer includes first - direction filaments and second - direction filaments that are wound around the axis of the catheter in an inclined manner, and the winding directions of the first - direction filaments and the second - direction filaments are opposite and intersect to form a plurality of intersection points; wherein, both the first - direction filaments and the second - direction filaments are flat filaments, the thickness direction of which extends along the radial direction of the catheter, and the ratio of the width to the thickness of the flat filament is 2:1 - 4:1; The catheter includes a main body section in the axial direction. In the main body section, the first braiding angle formed by the first - direction filaments and the axis of the catheter is 30° - 60°, and the second braiding angle formed by the second - direction filaments and the axis of the catheter is 30° - 60°.

[0006] Optionally, in the main body section, the first braiding angle increases from the proximal end to the distal end, the second braiding angle increases from the proximal end to the distal end, and the braiding density of the braided layer increases from the proximal end to the distal end; at the proximal end of the main body section, the first braiding angle and the second braiding angle are 30° to 40°; at the distal end of the main body section, the first braiding angle and the second braiding angle are 50° to 60°; in the main body section, the number of intersections per inch of the braided layer is 30 to 70.

[0007] Optionally, along the wire in the first direction, every three consecutive intersections form a cycle unit, where the wire in the first direction is located inside the wire in the second direction at two consecutive intersections, and the wire in the first direction is located outside the wire in the second direction at the other intersection; along the wire in the second direction, every three consecutive intersections form a cycle unit, where the wire in the second direction is located outside the wire in the first direction at two consecutive intersections, and the wire in the second direction is located inside the wire in the first direction at the other intersection.

[0008] Optionally, at the same axial position of the catheter, the first braiding angle is equal to the second braiding angle in size.

[0009] Optionally, the cross-section of the flat wire is rectangular, with a width of 0.08 mm to 0.15 mm and a thickness of 0.02 mm to 0.06 mm; the surface roughness Ra of the flat wire is ≤ 0.2 μm, and the edge chamfer radius of the flat wire is ≤ 0.01 mm.

[0010] Optionally, the catheter further includes a densification section in the axial direction, and the densification section is connected between the proximal end of the balloon and the main body section; in the densification section, the first braiding angle and the second braiding angle are 25° to 30°, and the number of intersections per inch of the braided layer is 70 to 80; the axial length of the densification section is 5 mm to 10 mm.

[0011] Optionally, in the main body section, the wall thickness of the outer layer decreases from the proximal end to the distal end; and / or; the material hardness of the outer layer decreases from the proximal end to the distal end.

[0012] Optionally, the inner wall of the inner layer has spiral microgrooves, the depth of the spiral microgrooves is less than 30 μm, and the pitch of the spiral microgrooves is 0.2 mm to 0.8 mm.

[0013] Optionally, the counterpulsation balloon catheter further includes a flexible distal end, and the flexible distal end is connected to the distal end of the balloon; the inner layer and the braided layer pass through the balloon and extend into the flexible distal end.

[0014] To solve the above technical problems, the present invention further provides an anti-pulse balloon catheter system, which includes: an anti-pulse device and the anti-pulse balloon catheter as described above; the anti-pulse device is connected to the catheter and is used to fill or extract the filling liquid through the catheter.

[0015] In summary, in the anti-pulse balloon catheter and the anti-pulse balloon catheter system provided by the present invention, the anti-pulse balloon catheter includes a balloon and a catheter; the balloon is communicated with the catheter and is configured to be expanded or contracted by filling or extracting the filling liquid through the catheter; the tube wall of the catheter includes an inner layer, a braided layer and an outer layer; the braided layer includes a first-direction wire and a second-direction wire that are coiled and arranged obliquely to the axis of the catheter, and the coiling directions of the first-direction wire and the second-direction wire are opposite and intersect to form a plurality of intersection points; wherein, both the first-direction wire and the second-direction wire are flat wires, the thickness direction of which extends along the radial direction of the catheter, and the ratio of the width to the thickness of the flat wire is 2:1 to 4:1; the catheter includes a main body section in the axial direction, in the main body section, the first braiding angle formed by the first-direction wire and the axis of the catheter is 30° to 60°, and the second braiding angle formed by the second-direction wire and the axis of the catheter is 30° to 60°.

[0016] With such a configuration, by introducing a braided layer into the tube wall of the catheter and further defining the braiding angles of the first-direction wire and the second-direction wire and the form of the wire, the braided layer formed by braiding can take into account better pushing force and flexibility, not only improving the pushing performance of the catheter, but also enhancing the anti-collapse ability of the lumen, ensuring the charging and discharging stability of the liquid medium in the high-bending path. Description of the Drawings

[0017] Those of ordinary skill in the art will understand that the provided drawings are used to better understand the present invention and do not constitute any limitation to the scope of the present invention.

[0018] Figure 1 is a schematic diagram of the anti-pulse balloon catheter system according to an embodiment of the present invention.

[0019] Figure 2 is a cross-sectional schematic diagram of the anti-pulse balloon catheter according to an embodiment of the present invention.

[0020] Figure 3 is a schematic diagram of the braided layer according to an embodiment of the present invention.

[0021] Figure 4 is a schematic diagram of the wire stacking relationship of two pressing one according to an embodiment of the present invention.

[0022] In the accompanying drawings: 1 - balloon; 2 - catheter; 20 - lumen; 21 - inner layer; 22 - braided layer; 220 - intersection point; 221 - first direction wire; 222 - second direction wire; 23 - outer layer; 24 - main body section; 25 - encryption section; 3 - inner tube; 4 - flexible head end; 6 - counterpulsation device; 61 - charging and discharging drive unit; 7 - pressure sensor. Detailed implementation manners

[0023] To make the objectives, advantages and features of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that the accompanying drawings are all in a very simplified form and not drawn to scale, and are only used to conveniently and clearly assist in explaining the objectives of the embodiments of the present invention. In addition, the structures shown in the accompanying drawings are often part of the actual structures. In particular, the accompanying drawings need to show different emphases and sometimes different scales are used.

[0024] As used in the present invention, the singular forms "a", "an", "one" and "the" include plural referents, the term "or" is generally used in the sense of "and / or", the term "several" is generally used in the sense of "at least one", the term "at least two" is generally used in the sense of "two or more". In addition, the terms "first", "second", "third" are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first", "second", "third" may explicitly or implicitly include one or at least two of such features. "One end" and "the other end", as well as "proximal end" and "distal end" generally refer to two corresponding parts, which include not only the endpoints. The terms "proximal end" and "distal end" are defined herein with respect to an intra-aortic balloon catheter having one end for insertion into the human body and a control end extending outside the body. The term "proximal end" refers to a position closer to the control end of the intra-aortic balloon catheter extending outside the body, and the term "distal end" refers to a position closer to the end of the intra-aortic balloon catheter inserted into the human body and thus farther from the control end of the intra-aortic balloon catheter. Optionally, in the context of manual or hand-operated applications, the terms "proximal end" and "distal end" are defined herein with respect to an operator such as a surgeon or clinician. The term "proximal end" refers to a position closer to the operator, and the term "distal end" refers to a position closer to the intra-aortic balloon catheter and thus farther from the operator. In addition, as used in the present invention, "mounted", "connected", "coupled", an element "disposed" on another element should be understood in a broad sense, generally only indicating that there is a connection, coupling, cooperation or transmission relationship between the two elements, and the two elements may be directly or indirectly connected, coupled, cooperated or transmitted through an intermediate element, and should not be construed as indicating or implying a spatial position relationship between the two elements, i.e., an element may be inside, outside, above, below or on one side of another element, etc., unless the content clearly indicates otherwise. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention may be understood according to specific circumstances. In addition, directional terms such as above, below, up, down, upward, downward, left, right, etc. are used with respect to the exemplary embodiments as shown in the figures, with the upward or upper direction towards the top of the corresponding figure and the downward or lower direction towards the bottom of the corresponding figure.

[0025] The object of the present invention is to provide an intra-aortic balloon catheter and an intra-aortic balloon catheter system to solve the safety problems existing in the existing balloon counterpulsation devices using gas as the filling medium.

[0026] The inventors' research found that in the field of minimally invasive interventional therapy, many balloon dilation catheters use liquids (such as normal saline, etc.) as the filling medium for the balloon. Compared with gases, using liquids (such as normal saline, etc.) as the filling medium for the balloon can improve safety. In some application scenarios where there are no special requirements for the charging and discharging speed, it is feasible to use liquids as the filling medium. However, in the case of an intra-aortic balloon pump catheter, since its intra-aortic balloon needs to expand and contract rapidly and periodically according to the heart rhythm based on the setting principle, if a liquid is used as the filling medium for the intra-aortic balloon, there will be a problem of limited charging and discharging efficiency, resulting in the inability to accurately and quickly make the intra-aortic balloon complete the required expansion and contraction.

[0027] The inventors' further research found that the main factor restricting the liquid charging and discharging efficiency lies in the catheter part. The flow of the liquid is much more sensitive to changes in the lumen shape than that of the gas. Once the lumen shape of the catheter bends, folds, deforms, or collapses in a complex blood vessel path, it will lead to unstable flow velocity, thereby affecting the precise control of balloon charging and discharging.

[0028] In order to use a liquid as the filling medium for the intra-aortic balloon, please refer to Figures 1 to 4 , an embodiment of the present invention provides an intra-aortic balloon pump catheter, which includes: a balloon 1 and a catheter 2; the balloon 1 is in communication with the catheter 2 and is configured to be inflated or deflated through the catheter 2 to achieve expansion or contraction; the tube wall of the catheter 2 includes an inner layer 21, a braided layer 22, and an outer layer 23; the braided layer 22 includes a first-direction wire 221 and a second-direction wire 222 that are wound around the axis of the catheter 2 in an inclined manner, and the winding directions of the first-direction wire 221 and the second-direction wire 222 are opposite and intersect to form a plurality of intersection points 220; wherein, both the first-direction wire 221 and the second-direction wire 222 are flat wires, the thickness direction of which extends along the radial direction of the catheter 2, and the ratio of the width to the thickness of the flat wire is 2:1 to 4:1; the catheter 2 includes a main body section 24 in the axial direction, in the main body section 24, the first braiding angle θ1 formed by the first-direction wire 221 and the axis of the catheter 2 is 30° to 60°, and the second braiding angle θ2 formed by the second-direction wire 222 and the axis of the catheter 2 is 30° to 60°.

[0029] Please refer to Figure 1 , in application, the distal end ( Figure 1 the left end) of the intra-aortic balloon pump catheter is used to be delivered to a predetermined part of the heart, such as the coronary sinus region, through vascular intervention, and the proximal end ( Figure 1extends out of the body from the right end thereof and is used to connect to the counterpulsation device 6. The counterpulsation device 6 is used to fill the balloon 1 with a filling fluid (such as normal saline, etc.) through the lumen 20 of the catheter 2 or extract the filling fluid through the lumen 20, so as to control the expansion or contraction of the balloon 1. The counterpulsation device 6 can accurately control the expansion and contraction of the balloon 1 by driving the filling or extracted filling fluid. The expansion and contraction of the balloon 1 are adapted to the counterpulsation requirements, that is, according to the rhythm of the heart, the blood flow in the coronary sinus is intermittently blocked, so as to achieve the purpose of controlling the intermittent increase and decrease of the blood pressure in the coronary sinus. The expansion size of the balloon 1 matches the size of the coronary sinus, and its outer diameter during expansion can be 4 mm to 16 mm, and the axial length of the balloon 1 along the catheter 2 can be 10 mm to 25 mm. The specific structure and the principle of expansion and contraction can refer to the prior art and will not be elaborated here.

[0030] Please refer to Figure 2 , the cross-section of the catheter 2 is preferably circular, and its outer diameter can be selected from 1.67 mm to 3.33 mm. In addition to being used for the circulation of the filling fluid, the lumen 20 of the catheter 2 can also be used for the inner tube 3 to pass through. In Figure 2 the exemplary embodiment shown, the inner tube 3 can be used as a guide wire channel during interventional delivery for the guide wire to penetrate, and its inner cavity can be compatible with guide wires of 0.018 in to 0.038 in. During the application process after implantation, the inner tube 3 can also be used for pressure detection. Its interior is filled with a liquid (such as blood or normal saline), and the proximal end of the inner tube 3 extending out of the body can be connected to the pressure sensor 7 to facilitate the monitoring of the venous sinus blood pressure.

[0031] The tube wall of the catheter 2 is a multi-layer composite wall, in which the inner layer 21 is preferably made of a polymer material with a low coefficient of friction, such as polytetrafluoroethylene (PTFE) or polyimide (PI), etc., to reduce the liquid flow resistance and enhance the smoothness. The braided layer 22 is preferably formed by braiding high-strength metal wire materials, and the materials thereof can include nitinol alloy wires, stainless steel wires or high-performance polymer fibers, etc. High-performance polymer fibers such as polyether ether ketone (PEEK) fibers or polyethylene terephthalate (PET) fibers, etc. The outer layer 23 is preferably made of flexible polyurethane (PU) or polyamide (PA), etc., to optimize the flexibility of the catheter 2 and reduce the friction with blood vessels. In some embodiments, a radiopaque material (such as tungsten, barium, etc.) can also be added to the outer layer 23. In an example of the manufacturing process, the metal wire material can be braided on the outer surface of the tube wall of the inner layer 21 to form a continuous and uniform braided layer 22, and then a polymer material is coated on the braided layer 22 and cured by heating to form the outer layer 23, so as to obtain the complete three-layer composite structure of the catheter 2.

[0032] Please refer to Figure 3, in this embodiment, the braided layer 22 is mainly braided with wire materials in two directions (the first-direction wire material 221 and the second-direction wire material 222). There are no restrictions on the quantity, specifications, materials, etc. of the first-direction wire material 221 and the second-direction wire material 222. The first-direction wire material 221 and the second-direction wire material 222 can have the same specifications (referring to cross-sectional dimensions, shapes, etc.), or different specifications; they can be made of the same material, or different materials.

[0033] Furthermore, the coiling directions of the first-direction wire material 221 and the second-direction wire material 222 here are opposite, which means that the helical directions of the two wire materials around the axis of the catheter 2 are opposite. If the first-direction wire material 221 is a right-handed helix, then the second-direction wire material 222 is a left-handed helix. Obviously, when two wire materials with opposite coiling directions are coiled on the inner layer 21, intersection points 220 will inevitably be generated, thus forming the braided layer 22.

[0034] The inventors have found through research that the magnitudes of the braiding angles (including θ1 and θ2) have a great influence on the mechanical properties of the braided layer 22 formed by coiling and braiding the wire materials. The braiding angle is a key parameter for optimizing the performance of the catheter 2. According to mechanical theory analysis, the pushing force F(push) of the catheter 2 = k·cos(θ1 + θ2), where k is the axial stiffness of the wire material. It can be understood that when the braiding angle decreases, the extending direction of the wire material is more parallel to the axis of the catheter 2, which will enhance the pushing force of the entire catheter 2 but reduce its flexibility. When the braiding angle increases, the braided layer 22 becomes more similar to a spring, which will improve the flexibility of the entire catheter 2 but weaken the pushing force.

[0035] The main body section 24 of the catheter 2 refers to most of the axial sections of the catheter 2, and its length can account for more than 90% of the entire catheter 2. Even in some embodiments, the catheter 2 can be entirely composed of the main body section 24. In other embodiments, the catheter 2 can also include some auxiliary sections, such as the densification section 25 (details will be described later), etc. It can be understood that the main body section 24 is the main body of the catheter 2, and its performance plays a decisive role in the performance of the catheter 2. In the main body section 24 of this embodiment, the first braiding angle θ1 is selected to be 30° - 60°, and the second braiding angle θ2 is selected to be 30° - 60°, which can enable the braided layer 22 formed by braiding to have both good pushing force and flexibility, not only improving the pushing performance of the catheter 2 but also enhancing the anti-collapse ability of the lumen 20, and ensuring the charging and discharging stability of the liquid medium in a highly curved path.

[0036] In addition, the morphology of the wire also has a great influence on the performance of the catheter 2. In this embodiment, both the first-direction wire 221 and the second-direction wire 222 are selected as flat wires. The thickness direction extends along the radial direction of the catheter 2, and the width direction is along the direction perpendicular to the axis of the wire itself, forming a certain angle with the wire axis in the circumferential direction of the catheter 2. Further, the inventors have found that when the ratio of the width to the thickness of the flat wire is 2:1 to 4:1, the flexibility and anti-kinking ability of the catheter 2 can be effectively balanced.

[0037] Further, the cross-section of the flat wire is rectangular (including a rounded rectangle or a chamfered rectangle with a small chamfer), the width is 0.08 mm to 0.15 mm, and the thickness is 0.02 mm to 0.06 mm; the surface roughness Ra of the flat wire ≤ 0.2 μm, and the edge chamfer radius of the flat wire ≤ 0.01 mm. The surface of the flat wire can be polished, and its surface roughness is low, which can significantly reduce the friction between the wires and the interfacial stress with the inner layer 21 or the outer layer 23.

[0038] The inventors have found that the braiding density also has an impact on the mechanical properties of the braided layer 22, and the braiding density is also an optional parameter for optimizing the performance of the catheter 2. The braiding density can be defined based on the number of all intersection points 220 in the entire circumference of the braided layer 22 per unit length of the catheter 2, such as the number of intersections per inch (PPI). Preferably, in the main body section 24, the number of intersections per inch (PPI) of the braided layer 22 is 30 to 70.

[0039] In addition to the braiding angle and the braiding density, the inventors have also found that the braiding order has an impact on the bending stability of the braided layer 22. The braiding order is mainly reflected in the overlapping relationship between the wires. Please refer to Figure 4 , in this embodiment, a wire overlapping relationship of two pressing one is preferably adopted. Specifically, along the first-direction wire 221, every three consecutive intersection points 220 form a cycle unit T. Among them, at two consecutive intersection points 220, the first-direction wire 221 is located inside the second-direction wire 222, and at the other intersection point 220, the first-direction wire 221 is located outside the second-direction wire 222; along the second-direction wire 222, every three consecutive intersection points 220 form a cycle unit T. Among them, at two consecutive intersection points 220, the second-direction wire 222 is located outside the first-direction wire 221, and at the other intersection point 220, the second-direction wire 222 is located inside the first-direction wire 221, and so on in a cycle. The wire overlapping relationship of two pressing one is beneficial to improving the stability of the catheter 2 during bending. After the anti-collapse test, after applying a radial compression force of 5 N to the catheter 2, the radial deformation of the lumen 20 is less than 5%.

[0040] The inventors' further research found that there are also differences in the requirements for pushing force and flexibility in different axial regions of the main body section 24. Specifically, the proximal region of the main body section 24 has a relatively higher requirement for pushing force, while the distal region of the main body section 24 has a relatively higher requirement for flexibility. This requires the main body section 24 to have varying properties axially. Based on this, preferably, the first braiding angle θ1 of the main body section 24 increases from the proximal end to the distal end, the second braiding angle θ2 increases from the proximal end to the distal end, and the braiding density of the braiding layer 22 increases from the proximal end to the distal end. Thus, the requirements for axially varying properties can be met.

[0041] In one embodiment, a lower braiding angle is used in the proximal region of the main body section 24. For example, the first braiding angle θ1 and the second braiding angle θ2 are 30° - 40° to provide strong axial support force; a larger braiding angle is used in the distal region of the main body section 24. For example, the first braiding angle θ1 and the second braiding angle θ2 are 50° - 60° to increase flexibility. It should be noted that the specific ranges and lengths of the proximal region and the distal region of the main body section 24 can be configured according to the actual situation. In a demonstration example, the region of the proximal 1 / 3 of the overall length of the main body section 24 can be set as the proximal region, the region of the distal 1 / 3 can be set as the distal region, and the middle 1 / 3 region can be set as the middle region. Further, the first braiding angle θ1 and the second braiding angle θ2 of the middle region can be set to 40° - 50° to facilitate the transitional change of mechanical properties. The braiding density of the braiding layer 22 can be adaptively changed according to the proximal region, the middle region, and the distal region. It should be noted that the above embodiment of dividing the main body section 24 into three regions, namely the proximal region, the middle region, and the distal region, is only a demonstration example and not a limitation on the regional division of the main body section 24. In some other embodiments, the main body section 24 can be divided into more regions, and this embodiment is not limited thereto.

[0042] In another embodiment, the first braiding angle θ1 and the second braiding angle θ2 of the main body section 24 can gradually increase from the proximal end to the distal end instead of changing regionally. The braiding density of the braiding layer 22 can also gradually increase from the proximal end to the distal end. Of course, from a microscopic perspective, dividing the main body section 24 into countless regions actually forms a gradually changing effect.

[0043] In some other embodiments, in the main body section 24, the wall thickness of the outer layer 23 decreases from the proximal end to the distal end; and / or; the material hardness of the outer layer 23 decreases from the proximal end to the distal end. In addition to controlling the axial property gradient of the main body section 24 by adjusting the braiding layer 22, in some other embodiments, the changes in the wall thickness and material of the outer layer 23 can also be used to achieve the adjustment of the axial property gradient of the main body section 24. For example, a gradually changing wall thickness can be adopted, or the distribution of rigidity and flexibility can be adjusted in different regions.

[0044] Optionally, in order to control the axial performance gradient of the main body section 24, the materials of the filaments in different axial regions of the braided layer 22 can also be adjusted. For example, in the proximal region, high-strength stainless steel wires can be selected for the first-direction filaments 221 and the second-direction filaments 222 to provide axial support and improve the pushing performance. In the distal region, nitinol alloy wires can be selected for the first-direction filaments 221 and the second-direction filaments 222 to provide a flexible memory effect and improve the distal adaptability.

[0045] Preferably, at the same axial position of the catheter 2, the first braiding angle θ1 is equal to the second braiding angle θ2 in size. When the first braiding angle θ1 and the second braiding angle θ2 at the same axial position of the catheter 2 are equal in size, it is beneficial to the circumferential uniformity of the catheter 2. Of course, the first braiding angle θ1 and the second braiding angle θ2 being equal in size at the same axial position of the catheter 2 is a preferred solution rather than a limitation. In some other embodiments, there may also be some differences between the first braiding angle θ1 and the second braiding angle θ2.

[0046] Please continue to refer to Figure 1 Optionally, the counterpulsation balloon catheter further includes a flexible distal end 4, and the flexible distal end 4 is connected to the distal end of the balloon 1; the inner layer 21 and the braided layer 22 pass through the balloon 1 and extend into the flexible distal end 4. The flexible distal end 4 is at the farthest end of the entire counterpulsation balloon catheter, and it will continuously pass through the blood vessels during the interventional delivery process. Extending the inner layer 21 and the braided layer 22 through the balloon 1 and into the flexible distal end 4 can improve the pushability of the flexible distal end 4 and make the counterpulsation balloon catheter easier to pass through complex vascular paths. The distal end of the flexible distal end 4 is open, and its inner cavity is communicated with the inner tube 3. Preferably, the flexible distal end 4 also has a number of lateral liquid passing holes communicated with the inner tube 3, so that even at the angled part of the tortuous blood vessel, even if the distal opening of the flexible distal end 4 is blocked, the blood can still be communicated with the inner tube 3 through the lateral liquid passing holes, thereby ensuring that the pressure sensor 7 can reliably detect the real-time blood pressure in the distal region of the counterpulsation balloon catheter.

[0047] Optionally, the catheter 2 further includes a reinforced section 25 in the axial direction, and the reinforced section 25 is connected between the proximal end of the balloon 1 and the main body section 24; in the reinforced section 25, the first braiding angle θ1 and the second braiding angle θ2 are 25° to 30°, and the number of intersections per inch of the braiding layer 22 is 70 to 80. Optionally, the axial length of the reinforced section 25 is 5 mm to 10 mm. When the balloon 1 is inflated, it will expand and dilate, and at this time, stress concentration and accompanying deformation are likely to occur at the connection between the catheter 2 and the balloon 1. In order to suppress the undesired expansion and deformation at the connection between the catheter 2 and the balloon 1 when the balloon is inflated, a reinforced section 25 is provided between the main body section 24 and the balloon 1. The reinforced section 25 has special configurations for both the braiding angle and the braiding density of the wire material. With such configurations, when the balloon is inflated, the radial deformation amount of the reinforced section 25 is not greater than 2%.

[0048] Optionally, the inner wall of the inner layer 21 has spiral microgrooves (not shown), the depth of the spiral microgrooves is less than 30 μm, preferably 20 μm to 30 μm, and the pitch of the spiral microgrooves is 0.2 mm to 0.8 mm, preferably 0.5 mm. In an alternative exemplary embodiment, the inner diameter of the lumen 20 of the catheter 2 is 1.2 mm ± 0.05 mm, and the cross-section is circular or quasi-circular (ellipticity ≤ 5%). It can be understood that the lumen 20 of the catheter 2 is substantially formed by the inner wall of the inner layer 21, and it is used for the flow of the filling liquid in application. The setting of the spiral microgrooves can effectively reduce the turbulent resistance and increase the flow rate. Based on the above configuration, after testing, the filling and discharging response time when the saline filling amount is 10 mL is not greater than 1.5 seconds, meeting the requirements.

[0049] Optionally, the counterpulsation balloon catheter further includes an optical fiber pressure sensor (not shown), and the optical fiber pressure sensor is disposed between the braiding layer 22 and the outer layer 23. In an exemplary embodiment, the type of the optical fiber pressure sensor can be selected as a Fabry - Perot optical fiber pressure sensor, and its diameter is not greater than 0.1 mm. The number of optical fiber pressure sensors can be selected as multiple, and the arrangement of the optical fiber pressure sensors can be embedded between the braiding layer 22 and the outer layer 23 at an axial interval of 10 mm along the catheter 2, and a total of 3 to 5 are arranged. The pressure measurement range of the optical fiber pressure sensor is -50 mmHg to 300 mmHg, and the resolution is 0.1 mmHg.

[0050] An embodiment of the present invention further provides an anti - pulsation balloon catheter system, which includes an anti - pulsation device 6 and the anti - pulsation balloon catheter as described above. The anti - pulsation device 6 is connected to the catheter 2 and is used to fill or extract the filling liquid through the catheter 2. Optionally, the anti - pulsation device 6 has a charging and discharging driving part 61. The power source of the charging and discharging driving part 61 can be selected from compressed air, oil pressure, electricity, etc. The specific driving structure of the charging and discharging driving part 61 can adopt an air pump, an engine, a motor, etc. to realize the filling or suction of the filling liquid. In a demonstration example, a pressure sensor 7 can be arranged on the anti - pulsation device 6. After the interventional delivery process is completed, the inner tube 3 can be connected to the pressure sensor 7. The specific structure and principle of the anti - pulsation device 6 can refer to the prior art and will not be elaborated here.

[0051] In summary, in the anti - pulsation balloon catheter and the anti - pulsation balloon catheter system provided by the present invention, the anti - pulsation balloon catheter includes a balloon and a catheter; the balloon is communicated with the catheter and is configured to be expanded or contracted by filling or extracting the filling liquid through the catheter; the tube wall of the catheter includes an inner layer, a braided layer and an outer layer; the braided layer includes a first - direction wire and a second - direction wire that are arranged in a coiled manner inclined to the axis of the catheter. The coiling directions of the first - direction wire and the second - direction wire are opposite and intersect to form a plurality of intersection points; wherein, both the first - direction wire and the second - direction wire are flat wires, the thickness direction of which extends along the radial direction of the catheter, and the ratio of the width to the thickness of the flat wire is 2:1 to 4:1; the catheter includes a main body section in the axial direction. In the main body section, the first braiding angle formed by the first - direction wire and the axis of the catheter is 30° to 60°, and the second braiding angle formed by the second - direction wire and the axis of the catheter is 30° to 60°. With such a configuration, by introducing a braided layer into the tube wall of the catheter and further defining the braiding angles of the first - direction wire and the second - direction wire and the form of the wires, the braided layer formed by braiding can take into account better pushing force and flexibility, not only improving the pushing performance of the catheter, but also enhancing the anti - collapse ability of the lumen, ensuring the charging and discharging stability of the liquid medium in the high - bending path.

[0052] It should be noted that the above - mentioned several embodiments can be combined with each other. The above description is only a description of the preferred embodiments of the present invention and does not limit the scope of the present invention in any way. Any changes and modifications made by those of ordinary skill in the field of the present invention according to the above - disclosed content fall within the protection scope of the present invention.

Claims

1. A counterpulsation balloon catheter, characterized in that: The invention comprises a balloon and a catheter; the balloon is connected to the catheter and is configured to expand or contract by filling or withdrawing filling fluid through the catheter; The tube wall of the catheter comprises an inner layer, a braided layer and an outer layer; the braided layer comprises a first-direction wire and a second-direction wire arranged in a coiled manner oblique to the axis of the catheter, the first-direction wire and the second-direction wire are coiled in opposite directions and intersect to form a plurality of intersections; wherein the first-direction wire and the second-direction wire are both flat wires, the thickness direction of which extends in the radial direction of the catheter, and the ratio of the width to the thickness of the flat wire is 2:1 to 4:1; The catheter comprises a main body section in the axial direction, in which a first braiding angle formed by the first direction wires and the axis of the catheter is 30°~60°, and a second braiding angle formed by the second direction wires and the axis of the catheter is 30°~60°.

2. The counterpulsation balloon catheter according to claim 1, characterized in that: In the main body segment, the first braiding angle increases from the proximal end to the distal end, the second braiding angle increases from the proximal end to the distal end, and the braiding density of the braided layer increases from the proximal end to the distal end; at the proximal end of the main body segment, the first braiding angle and the second braiding angle are 30°~40°; at the distal end of the main body segment, the first braiding angle and the second braiding angle are 50°~60°; in the main body segment, the number of crossing points per inch of the braided layer is 30~70.

3. The counterpulsation balloon catheter according to claim 1, characterized in that: Along the first direction wire, every three consecutive intersections form a circulation unit, wherein at two consecutive intersections, the first direction wire is located on the inner side of the second direction wire, and at another intersection, the first direction wire is located on the outer side of the second direction wire; along the second direction wire, every three consecutive intersections form a circulation unit, wherein at two consecutive intersections, the second direction wire is located on the outer side of the first direction wire, and at another intersection, the second direction wire is located on the inner side of the first direction wire.

4. The counterpulsation balloon catheter according to claim 1, characterized in that: At the same axial position of the catheter, the first braiding angle is equal to the second braiding angle.

5. The counterpulsation balloon catheter according to claim 1, characterized in that: The cross section of the flat wire is rectangular, the width is 0.08mm-0.15mm, and the thickness is 0.02mm-0.06mm; the surface roughness Ra of the flat wire is ≤0.2μm, and the edge chamfer radius of the flat wire is ≤0.01mm.

6. The counterpulsation balloon catheter according to claim 1, characterized in that: The catheter also includes a densification segment in the axial direction, which is connected between the proximal end of the balloon and the main body segment; in the densification segment, the first braiding angle and the second braiding angle are 25°~30°, and the number of crossing points per inch of the braided layer is 70~80; the axial length of the densification segment is 5mm~10mm.

7. The counterpulsation balloon catheter according to claim 1, characterized in that: In the main body section, the wall thickness of the outer layer decreases from the proximal end to the distal end; and / or; the material hardness of the outer layer decreases from the proximal end to the distal end.

8. The counterpulsation balloon catheter according to claim 1, characterized in that: The inner wall of the inner layer has spiral microgrooves, the depth of the spiral microgrooves is less than 30 μm, and the pitch of the spiral microgrooves is 0.2 mm to 0.8 mm.

9. The counterpulsation balloon catheter according to claim 1, characterized in that: The counterpulsation balloon catheter also includes a flexible head end, which is connected to the distal end of the balloon; the inner layer and the braided layer pass through the balloon and extend into the flexible head end.

10. A counterpulsation balloon catheter system, characterized in that: include: A counterpulsation device and a counterpulsation balloon catheter according to any one of claims 1 to 9; The counterpulsation device is connected to the catheter and is used to fill or extract the filling fluid through the catheter.

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