A medical guide wire and a prosthetic valve delivery system

Abstract

The application relates to a medical guide wire and a prosthetic valve delivery system, wherein the guide wire comprises a core wire, a fixing part and a spring coil; the core wire comprises a covered section and a bare section arranged in sequence from the distal end to the proximal end of the core wire, and part of the covered section is in a curled structure; the fixing part is connected to the distal end of the covered section; the spring coil is in a cylindrical structure, is inserted into the outer periphery of the covered section, and the proximal end of the spring coil is connected to the proximal end of the covered section, and the distal end of the spring coil is connected to the fixing part. The curled structure in various size specifications can be wound by the unique specification core wire to adapt to ventricles of different sizes, and the curled structure in each size specification has a pressure deformation capacity of 0.4-0.7 N in the first direction, and the curve recovery rate is greater than or equal to 95%.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of medical devices, in particular to a medical guide wire and a prosthetic valve delivery system. BACKGROUND

[0002] In recent years, minimally invasive surgery has been rapidly promoted, and such surgery usually requires a medical guide wire to establish a vascular access. For example, in transcatheter aortic valve implantation, a guide wire needs to be inserted into the femoral artery, and the distal end of the guide wire needs to be anchored in the ventricle, and then other pipelines are inserted under the guidance of the guide wire. In order to achieve the anchoring function, the distal end of the guide wire is usually in a curled structure to fit the ventricular wall, but the curled structure needs to be in a straight line during arterial transmission. In the prior art, the state of the curled structure is controlled by different temperatures, and the curled structure is set to be a five-segment or three-segment structure with equal diameter or variable diameter.

[0003] However, the size of the curled structure needs to adapt to the different sizes of the ventricle, so the curled structure is made into different specifications, but the deformation ability of the curled structure under the compression of the ventricle and the self-recovery ability of the curled structure are different in actual use, which leads to the fact that some specifications of the curled structure increase the burden of ventricular contraction, and some specifications of the curled structure are difficult to recover to the original state after being compressed by the ventricular contraction, resulting in the problem of insufficient anchoring ability. Therefore, it is necessary to individually design and manufacture a core wire suitable for different specifications of the curled structure, which has a large processing difficulty and high cost. SUMMARY

[0004] Therefore, the present application provides a medical guide wire and a prosthetic valve delivery system, which can wind a core wire of the same size specification to form curled structures of multiple size specifications to adapt to ventricles of different sizes, and the deformation ability of the curled structures of each size specification under compression in the first direction is within the range of 0.4-0.7N, and the curve recovery rate is greater than or equal to 95%.

[0005] The technical scheme adopted by the present application is as follows:

[0006] A medical guide wire is used in transcatheter intervention, and the guide wire comprises a core wire, a fixing member and a spring coil. The core wire comprises a covered section and a bare section arranged in sequence from the distal end to the proximal end, and part of the covered section is in a curled structure. The fixing member is connected to the distal end of the covered section. The spring coil is in a cylindrical structure, is sleeved on the outer periphery of the covered section, and its proximal end is connected to the proximal end of the covered section, and its distal end is connected to the fixing member.

[0007] The covering section comprises a first constant diameter section, a first taper section and a second constant diameter section arranged in sequence from the distal end to the proximal end, the first taper section is a taper section, the taper is 20:10000-52:10000, the diameter of the large end is 0.5-0.6mm, and the length of the first taper section is 100mm-150mm; the diameter of the first constant diameter section is equal to that of the small end of the first taper section, the diameter of the second constant diameter section is equal to that of the large end, and the proximal end of the second constant diameter section is connected with the exposed section;

[0008] The first taper section in the first constant diameter section and the part of the first taper section connected therewith form the crimping structure, the length of the part of the first taper section used to form the crimping structure accounts for 70%-90% of the total length of the first taper section, so that the starting point of the crimping structure is located in the first taper section, different size specifications of the crimping structure can be formed by selecting different starting points in the first taper section using the same size specification of the core wire, and the larger the size specification of the crimping structure, the greater the proportion of the length of the part of the first taper section used to form the crimping structure accounts for the total length of the first taper section, the number of winding turns of the crimping structure is not less than 1.5 turns, the outermost turn is formed by the first taper section, and the crimping structure is located in the same plane in a natural state and can be compressed or unfolded into a strip-shaped structure under the action of an external force.

[0009] Preferably, when the size specification of the crimping structure is that the size in the first direction is 20mm-32mm and the size in the second direction is 25mm-37mm, the length of the first taper section in the crimping structure accounts for 70%-78% of the total length of the first taper section;

[0010] When the size specification of the crimping structure is that the size in the first direction is 30mm-43mm and the size in the second direction is 35mm-48mm, the length of the first taper section in the crimping structure accounts for 76%-85% of the total length of the first taper section;

[0011] When the size specification of the crimping structure is that the size in the first direction is 40mm-50mm and the size in the second direction is 46mm-55mm, the length of the first taper section in the crimping structure accounts for 83%-90% of the total length of the first taper section;

[0012] Wherein, the normal direction of the crimping structure at the starting point thereof is the first direction, and the direction perpendicular to the first direction is the second direction.

[0013] Preferably, the taper of the first taper section is 20:10000-30:10000, the diameter of the large end is 0.55mm-0.58mm, and the length of the first taper section is 120mm-140mm.

[0014] Preferably, the diameter of the small end of the first variable diameter section is 0.08-0.2mm, and the ratio of the length of the first constant diameter section to the length of the first variable diameter section is 0.067-0.2.

[0015] Preferably, the length of the second constant diameter section is 50-100mm.

[0016] Preferably, in the direction from the distal end to the proximal end, the bare section comprises a second variable diameter section and a third constant diameter section arranged in sequence, and the diameter of the second variable diameter section gradually increases; the third constant diameter section is connected with the covered section through the second variable diameter section, the small end of the second variable diameter section has the same diameter as the second constant diameter section, and the large end of the second variable diameter section has the same diameter as the third constant diameter section.

[0017] Preferably, the diameter of the third constant diameter section is 0.762-0.889mm, the outer diameter of the spring coil is equal to the diameter of the third constant diameter section, and the length of the second variable diameter section is 5-100mm.

[0018] Preferably, the bare section is a constant diameter section.

[0019] Preferably, the spring coil has a cylindrical structure, one end of the inner wall of the spring coil is attached to the outer peripheral surface of the second constant diameter section, and the other end of the inner wall of the spring coil is connected with the fixing member.

[0020] Preferably, the gap between two adjacent turns of the spring coil is 0.01mm-0.04mm.

[0021] Preferably, PTFE coating is arranged on the outer peripheral surface of the bare section and the turns of the spring coil.

[0022] Preferably, the material of the core wire and the spring coil is selected from 304 stainless steel and nickel-titanium alloy.

[0023] The application also relates to a delivery system for a prosthetic valve, comprising a sheath and the medical guide wire as described above, the medical guide wire being capable of being inserted into the sheath, and the coiled structure being substantially in a strip shape in the sheath.

[0024] The application has the following advantages:

[0025] The medical guide wire of the present application, by designing the core wire structure of the coating section into an equal-diameter, variable-diameter, equal-diameter simple three-section structure, designing unique parameter sizes for the three-section structure, and setting the starting point of the coiled structure in the variable-diameter section, can only use a size specification of core wire to make coiled structures of different size specifications by selecting different length proportions of the variable-diameter section, can meet the size requirements of different sizes of ventricles, and can ensure the consistency of the deformation ability and the curve recovery rate of the coiled structure, greatly reducing the design and manufacturing costs, and achieving the advantages of reliable anchoring and no damage to the ventricular wall.

[0026] The taper of the first variable-diameter section is designed to be 20:10000-52:10000, the diameter of the large end is 0.5-0.6mm, and the length is 100mm-150mm, and the coiled structure is designed as a planar structure, and the length of the part in the first variable-diameter section for forming the coiled structure accounts for 70%-90% of the total length of the first variable-diameter section, so that coiled structures of different size specifications can be manufactured by selecting different positions on the first variable-diameter section as the starting point of the coiled structure to meet different sizes of ventricles, and the outermost circle of the coiled structure, especially the half circle connected to the starting point, has a certain range of stiffness, so that the coiled structure has good elasticity, so that no matter what size specification the coiled structure is manufactured, the compression deformation ability under the same pressure in the first direction is within the range of 0.4-0.7N, and the recovery rate of the curve after deformation is greater than or equal to 95%, so that during the ventricular contraction process, the burden on the ventricle due to the extrusion of the coiled structure is not increased, and during the ventricular diastole, the coiled structure can recover to the original state under the elastic recovery ability of itself; at the same time, the present application can provide greater support force for the coiled structure by setting the second equal-diameter section, so that the coiled structure is always anchored at a fixed position in the ventricle and adheres to the inner wall of the ventricle during the diastole and systole of the ventricle; and the present application is coated with a spring coil from the second equal-diameter section, so that the spring coil cooperates with the second equal-diameter section with a larger diameter to fix the spring coil well, and then coats the entire coiled structure and other sections close to the coiled structure to prevent damage to the ventricular wall during anchoring. BRIEF DESCRIPTION OF DRAWINGS

[0027] The above and other objects, features and advantages of the present application will become more apparent from the following description of embodiments of the present application with reference to the accompanying drawings, in which:

[0028] Figure 1 is a structure diagram of a medical guide wire in a natural state;

[0029] Figure 2 is a structure diagram of one embodiment of a core wire in a natural state;

[0030] Figure 3 Partial sectional view of the medical guide wire in the unwound state of the coiled structure;

[0031] Figure 4 Structural schematic diagram of another embodiment of the core wire in the natural state.

[0032] Wherein: 1, core wire; 2, covering section; 3, bare section; 4, spring coil; 5, fixing piece; 6, guide section; 7, anchoring section; 21, first constant diameter section; 22, first variable diameter section; 23, second constant diameter section; 24, coiled structure; 25, starting point; 26, deformation section; 31, second variable diameter section; 32, third constant diameter section. DETAILED DESCRIPTION

[0033] The present application is described in the following based on embodiments, but the present application is not limited to these embodiments only. In the following detailed description of the present application, some specific details are described in detail in order to avoid obscuring the present application, and well-known methods, procedures, processes, elements are not described in detail.

[0034] In addition, those skilled in the art should understand that the drawings provided herein are for illustrative purposes only, and the drawings are not necessarily drawn to scale.

[0035] Unless the context clearly requires otherwise, throughout the description and the claims, the words "comprise", "comprising", and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is to say, in the sense of "including, but not limited to".

[0036] In the description of the present application, it should be understood that the terms "first", "second", etc. are used only for the purpose of description and should not be construed as indicating or implying relative importance. In addition, in the description of the present application, unless otherwise specified, the meaning of "multiple" is two or more.

[0037] In the present application, taking transcatheter aortic valve implantation as an example, "proximal end" is the end away from the artificial heart valve during the operation, and "distal end" is the end close to the artificial heart valve during the operation, see Figure 3 for the direction shown.

[0038] The present application provides a medical guide wire (hereinafter referred to as "guide wire") for transcatheter intervention, for example, for transcatheter aortic valve implantation, and can also guide other delivery systems or treatment systems into the surgical site. See Figures 1-4, the guide wire comprises a core wire 1, a fixing member 5 and a spring coil 4, the core wire 1 is of an integral structure, and the core wire 1 comprises, from a distal end to a proximal end thereof, a coated section 2 and a bare section 3 arranged in sequence, a part of the coated section 2 is heat set so as to form a crimped structure 24, and of course, the coated section 2 can be manually wound to form the crimped structure 24; the fixing member 5 is connected to the distal end of the coated section 2. The spring coil 4 is of a cylindrical structure, which can be a cylindrical tube structure, the spring coil 4 is sleeved on the outer periphery of the coated section 2, the proximal end of the spring coil 4 is connected to the proximal end of the coated section 2, and the distal end of the spring coil 4 is connected to the fixing member 5, the spring coil 4 covers the outer periphery of the entire coated section 2 from the outside, and since the part of the coated section 2 is of the crimped structure 24, the crimped structure 24 also causes the spring coil 4 outside the crimped structure 24 to be crimped, so that the distal end part of the guide wire is crimped, for the convenience of description, the crimped distal end part of the guide wire is referred to as an anchoring section 7, and the part of the guide wire which is not crimped is referred to as a guide section 6.

[0039] The coated section 2 comprises, from the distal end to the proximal end thereof, a first constant-diameter section 21, a first variable-diameter section 22 and a second constant-diameter section 23 arranged in sequence, the first variable-diameter section 22 is a tapered section, the taper is 20:10000-52:10000, for example, 20:10000, 30:10000, 40:10000, 50:10000 or 52:10000, the diameter of the large end is 0.5-0.6 mm, for example, 0.5 mm, 0.52 mm, 0.55 mm, 0.58 mm or 0.6 mm, etc., the length of the first variable-diameter section 22 is 100-150 mm, for example, 100 mm, 110 mm, 120 mm, 130 mm, 140 mm or 150 mm, etc.; the diameter of the small end of the first variable-diameter section 22 is equal to that of the first constant-diameter section 21, and the diameter of the large end of the second constant-diameter section 23 is equal to that of the bare section 3.

[0040] Referring to Figure 2 The crimped structure 24 comprises the first constant-diameter section 21 and the part of the first variable-diameter section 22 connected thereto, the length of the part of the first variable-diameter section 22 used to form the crimped structure 24 accounts for 70%-90% of the total length of the first variable-diameter section 22, so that the starting point 25 of the crimped structure 24 is located in the first variable-diameter section 22, so as to be able to use the same size specification of the core wire 1 to form crimped structures 24 of different size specifications by selecting different starting points 25 in the first variable-diameter section 22, and the larger the size specification of the crimped structure 24 is, the greater the proportion of the length of the part of the first variable-diameter section 22 used to form the crimped structure 24 accounts for the total length of the first variable-diameter section 22, the number of winding turns of the crimped structure 24 is not less than 1.5 turns, the outermost turn of the crimped structure 24 is formed by the first variable-diameter section 22, the crimped structure 24 is located in the same plane in a natural state, and under the action of an external force, the crimped structure 24 can be compressed or unfolded into a strip-shaped structure, the strip-shaped structure here is only relative to the crimped structure, and is not limited to a straight line type, for example, it can be a slightly curved structure.

[0041] Reference Figure 3 The covering section 2 is sequentially divided into a first constant diameter section 21, a first variable diameter section 22 and a second constant diameter section 23 from the distal end to the proximal end. The diameter of the first constant diameter section 21 is the same at each location, the diameter of the second constant diameter section 23 is the same at each location, and the diameter of the first variable diameter section 22 is different at each location. In the direction from the distal end to the proximal end, the diameter of the first variable diameter section 22 gradually increases, the first variable diameter section 22 is conical (the top of the conical shape is not a sharp angle, but has a certain diameter, or the variable diameter section 22 can be referred to as a truncated cone), and the generatrix of the first variable diameter section 22 is a straight line. The distal end (i.e., the small end) of the first variable diameter section 22 is equal in diameter to the first constant diameter section 21, so that the first constant diameter section 21 and the first variable diameter section 22 can smoothly transition, the proximal end (i.e., the large end) of the first variable diameter section 22 is equal in diameter to the second constant diameter section 23, so that the first variable diameter section 22 and the second constant diameter section 23 can smoothly transition, thereby ensuring the structural strength at the junction between the first constant diameter section 21 and the first variable diameter section 22 and at the junction between the first variable diameter section 22 and the second constant diameter section 23. Of course, in other embodiments, the diameter of the first constant diameter section 22 can be smaller than the diameter of the distal end of the first variable diameter section 22, but the trend of the covering section 2 from the distal end to the proximal end is from small to large.

[0042] Throughout the core wire 1, the diameter of the first constant diameter section 21 is the smallest, and specifically, the diameter of the small end of the first variable diameter section 22 is 0.08-0.2 mm, such as 0.08 mm, 0.1 mm, 0.13 mm, 0.15 mm, 0.18 mm or 0.2 mm, etc. In embodiments in which the diameter of the first constant diameter section 21 is equal to the diameter of the small end of the first variable diameter section, the diameter of the first constant diameter section 21 is also 0.08-0.2 mm. Such a structure makes the first constant diameter section 21 very thin, so that the first constant diameter section 21 is easily deformed by external force. Therefore, the guide wire can more easily perceive vibrations during transportation and anchoring, thereby feeding back to the doctor, facilitating the doctor to confirm the status of the distal end of the guide wire, and facilitating the performance of transcatheter aortic valve implantation.

[0043] The first constant diameter section 21 and the portion of the first variable diameter section 22 connected thereto are bent into a crimped structure 24 by artificial or heat setting, so that the crimped structure 24 has elasticity and can be deformed under pressure in a first direction and gradually recover to the original state when the external force is reduced or removed. The crimped structure 24 also has elasticity in the crimping direction, specifically, it can be unfolded into a strip shape under the action of external force, and after the external force is removed, the crimped structure 24 can recover to the original state under the action of its own elasticity, i.e., it will recover into the crimped structure 24 again; wherein the normal direction of the crimped structure 24 at its starting point 25 is the first direction, and the direction perpendicular to the first direction is the second direction.

[0044] The spring coil 4 is substantially equal in length to the covering section 2, the spring coil 4 is sleeved on the outer periphery of the entire covering section 2, and the two ends of the spring coil 4 are connected (including direct connection and indirect connection) with the two ends of the covering section 2. As mentioned above, the first constant diameter section 21 and part of the first variable diameter section 22 in the covering section 2 are in a curled structure 24, and in the natural state, the curled structure 24 will drive the corresponding part of the spring coil 4 outside it to be in a curled state, thereby forming a curled anchor section 7 on the guide wire. The guide wire is first located in the sheath tube in the transcatheter aortic implantation procedure, and the distal end of the guide wire is sent to the heart chamber through the sheath tube. Due to the restriction of the sheath tube, the guide wire is basically unfolded into a strip-shaped structure (the curled structure 24 is unfolded into a strip-shaped structure, so that the anchor section 7 is also unfolded into a strip-shaped structure); after the distal end of the guide wire reaches the heart chamber, the distal end of the guide wire extends out of the sheath tube, and the sheath tube no longer restricts the distal end of the guide wire. The first constant diameter section 21 and part of the first variable diameter section 22 connected thereto are restored from the strip-shaped structure to the curled structure 24 under the action of their own elasticity, so that the anchor section 7 of the guide wire is also curled, and at least in the first direction, the anchor section is in contact with the inner wall of the heart chamber, so that the anchor section 7 of the guide wire can be anchored in the heart chamber.

[0045] The curled structure 24 of the present application is located in the same plane, that is, the axes of the core wires of each part in the curled structure 24 are on the same plane, and the distal end of the first constant diameter section 21 is located in the curled structure 24, so that the distal end of the guide wire is located in the curled anchor section 7. When the heart chamber contracts and presses the curled anchor section 7, the distal end of the guide wire does not come into contact with the heart chamber wall, thereby preventing the distal end of the anchor section 7 from injuring the heart chamber wall.

[0046] The number of turns of the curled structure 24 is not less than 1.5 turns, for example, 1.5 turns, 2 turns, 2.5 turns or 3 turns, etc. Generally, the number of turns of the curled structure 24 will not exceed 3 turns, so that there is enough spacing between the outermost turn of the curled structure 24 and the adjacent inner turn, so that only the outermost turn comes into contact with the heart chamber wall during the process of the heart chamber pressing the curled structure.

[0047] The outermost circle of the coiled structure 24 is formed by the first variable diameter section 22, the diameter of the large end of the first variable diameter section 22 is 0.5-0.6mm, so that the half circle connected with the starting point 25 in the coiled structure 24 (for the convenience of description, the half circle is called the deformed section 26) has a certain stiffness, when the ventricle contracts, the ventricular wall presses the coiled structure 24 from the first direction, so that the coiled structure 24 deforms, and the end points at both ends of the deformed section 26 move inward, and when the ventricle relaxes, the deformed section 26 recovers to the original state under the joint action of its own deformation ability and the support force provided by the second constant diameter section 23, so that the coiled structure 24 recovers to the original state. In the above process, the local spring coil 4 on the outer side of both ends of the deformed section 26 is always in contact with the ventricular wall, so that the coiled anchor section 7 can always be anchored in the ventricle.

[0048] Due to the difference of patients, the size of the ventricle is actually different, for example, the size of the ventricle of a child and the size of the ventricle of an adult will have a large difference, therefore, the size of the coiled structure 24 should be adapted to the size of the corresponding ventricle.

[0049] Due to the difference in size of the coiled structure 24, the length of the deformed section 26 in the coiled structure 24 will change, specifically, when the same starting point is selected, the smaller the size of the coiled structure 24 is, the smaller the length of the deformed section 26 is, and the curvature is larger, which will inevitably increase the stiffness of the deformed section 26, and the recovery ability of the deformed section 26 is stronger, but on the other hand, the difficulty of compression of the deformed section 26 is also increased, which increases the working burden of the ventricle during contraction, affecting the normal work of the ventricle of the patient; on the contrary, the larger the size of the coiled structure 24 is, the larger the length of the deformed section 26 is, the smaller the curvature is, the smaller the stiffness of the deformed section 26 is, and the deformed section 26 is easier to be compressed, and the recovery ability is limited, although the burden of the ventricle during contraction is reduced, but when the ventricle relaxes, the deformed section 26 may not recover to the original state, which causes the coiled anchor section 7 to be unable to effectively anchor in the ventricle, thereby affecting the operation.

[0050] The present application can wind the same specification core wire 1 into different size specifications of the coiled structure 24 according to the needs to adapt to different sizes of the ventricle, only the starting point 25 of each size specification of the coiled structure 24 on the first variable diameter section 22 is different. The smaller the size specification of the coiled structure 24 in the present application, the shorter the length of the first variable diameter section 22 in the coiled structure 24, so that the starting point 25 is farther away from the proximal end (large end) of the first variable diameter section 22, the diameter of the core wire 1 at the starting point 25 is smaller, so that the diameter of the whole deformed section 26 is smaller, so that the stiffness of the deformed section 26 is relatively weakened, and the elastic recovery ability of the deformed section 26 is relatively enhanced, so that the deformation ability of the deformed section 26 is within a reasonable interval range, so that the ventricle can easily compress the coiled structure 24, and the coiled structure 24 can recover to the original state under the action of the self-elastic recovery force when the ventricle is diastolic, so that the anchoring section 7 can be anchored in the ventricle. Similarly, the larger the size specification of the coiled structure 24, the longer the length of the first variable diameter section 22 in the coiled structure 24, so that the starting point 25 is closer to the proximal end of the first variable diameter section 22, the diameter of the core wire 1 at the starting point 25 is larger, so that the diameter of the whole deformed section 26 is increased, and the length of the deformed section 26 is also increased, so that the deformation ability of the deformed section 26 is within a reasonable interval range, which can make the ventricle contract to easily compress the anchoring section 7, and the anchoring section can gradually recover to the original state with the diastole of the ventricle. Among them, the same specification core wire 1 refers to the medical guide wire used to manufacture each specification of the coiled structure 24 in the unfolded state of the coiled structure (or the anchoring section 7), the structure and size of each part are the same, including the same length of the covered section 2 and the exposed section 3 of the core wire 1, and the diameters of each part are consistent.

[0051] In the present application, the position of the starting point 25 of the coiled structure 24 corresponds to the size specification of the coiled structure 24, so that the same specification core wire 1 wound into different size specifications of the coiled structure 24 has different starting points 25, so that each coiled structure 24 has basically the same deformation ability and elastic recovery ability.

[0052] The core wires 1 of the same specification are respectively wound into the corresponding three size specifications of the crimped structures 24 according to the starting point positions of the crimped structures arranged in the present application, and then the three crimped structures 24 are respectively subjected to compression tests and compression load tests to respectively detect the compression deformation abilities and the curve recovery rates of each, and the results are shown in Table 1. In the experiment, for each specification of the crimped structure, the starting point of the crimped structure 24 is fixed, the size of the crimped structure 24 in the first direction is measured and recorded as A1, a compression force is applied to the crimped structure 24 in the first direction, when the crimped structure is compressed to 0.7A1 in the first direction, the compression force is removed, and this is repeated N times (preferably, N is 10-4000), when the crimped structure recovers to the natural state for the last time, the size of the crimped structure 24 in the first direction at this time is measured and recorded as A2, and the ratio of A2 to A1 is calculated, which is used to represent the curve recovery rate of the crimped structure. Finally, the crimped structure 24 is compressed in the first direction to 0.7A1 by using a tensile testing machine, and the force of the tensile testing machine during this process is read, and the maximum force during this process is taken as the maximum elastic force value of the crimped structure 24, which is used to represent the compression deformation ability of the crimped structure.

[0053] Table 1

[0054] As can be seen from Table 1, the compression deformation abilities of the three size specifications of the crimped structures 24 are very close (in the range of 0.4-0.7N), and are all basically within the range of the extrusion force generated by the ventricle during contraction, so that the ventricle can easily and basically without burden compress the crimped structure 24 to deform. And the curve recovery rates of the above three size specifications of the crimped structures 24 are all greater than 95%, so that during ventricular diastole, the anchoring segment 7 can follow the ventricular diastole to the original state under the action of the self-elastic recovery force, so that the anchoring segment can always adhere to the inner wall of the ventricle, thereby ensuring that the distal end of the guide wire can always be anchored in the ventricle.

[0055] Of course, the above compression test and compression load test can also be performed on the guide wire, specifically, the crimped anchoring segment 7 of the guide wire is subjected to the related test, only the crimped structure above is replaced by the anchoring segment. Since the deformation ability and the curve recovery rate of the anchoring segment 7 are mainly determined by the crimped structure, the compression deformation ability and the curve recovery rate of the anchoring segment 7 are basically the same as those of the corresponding crimped structure 24.

[0056] The curling structure 24 has strong curve recovery capability. When the anchoring section 7 is curled and anchored in the ventricle, the ventricular contraction will compress the anchoring section 7, so that the curled anchoring section 7 is deformed, and the curling structure 24 is also deformed. When the ventricle is diastolic, the curling structure 24 basically recovers to the original state under the action of its own deformation capability, so that the curled anchoring section 7 can deform correspondingly with the contraction and diastole of the ventricle.

[0057] The spring coil 4 is wrapped outside the covering section 2, which prevents damage to the ventricular wall during the delivery and anchoring of the guide wire. The curling structure 24 is arranged in the same plane, so that the anchoring section 7 is basically in the same plane even if it is compressed, and the distal end of the guide wire basically does not protrude out of the plane to stab the ventricular wall. In addition, the first variable diameter section 22 is arranged, so that the diameter of the distal end region of the core wire 1 is smaller than the inner diameter of the spring coil 4, resulting in a relatively large space between the spring coil 4 and the core wire 1. The distal ends of the two are directly fixed and connected, and the reliability is low. The fixing member 5 is arranged to connect the distal end of the spring coil 4 and the distal end of the covering section 2 together through the fixing member 5. Specifically, the distal end of the spring coil 4 can be directly connected with the end face of the fixing member 5, and the two can be connected by glue or laser welding. The proximal end of the spring coil 4 can be connected with the proximal end of the second constant diameter section 23 through glue or laser welding after being sleeved and matched, so as to fix the spring coil 4 well and ensure the effectiveness of the covering of the covering section 2.

[0058] Specifically, the size specification of the curling structure and the position of the starting point are as follows:

[0059] When the size specification of the curling structure 24 is that the size in the first direction is 20mm-32mm and the size in the second direction is 25mm-37mm, the size in the first direction is for example 20mm, 25mm, 28mm, 30mm or 32mm, and the size in the second direction is for example 25mm, 28mm, 32mm, 35mm or 37mm. The length of the first variable diameter section 22 in the curling structure 24 accounts for 70%-78% of the total length of the first variable diameter section 22, for example 70%, 72%, 75% or 78%.

[0060] As shown in Figure 2 When the size specification of the curling structure 24 is that the size in the first direction is 30mm-43mm and the size in the second direction is 35mm-48mm, the size in the first direction is for example 30mm, 33mm, 37mm, 39mm or 43mm, and the size in the second direction is for example 35mm, 38mm, 40mm, 43mm, 46mm or 48mm. The length of the first variable diameter section 22 in the curling structure 24 accounts for 76%-85% of the total length of the first variable diameter section 22, for example 76%, 79%, 82% or 85%.

[0061] like Figure 4 As shown, when the dimensions of the coiled structure 24 are 40mm-50mm in the first direction and 46mm-55mm in the second direction, the dimensions in the first direction are, for example, 40mm, 43mm, 45mm, 47mm or 50mm, and the dimensions in the second direction are, for example, 46mm, 48mm, 50mm, 53mm or 55mm, and the length of the first variable diameter section 22 in the coiled structure 24 accounts for 83%-90% of the total length of the first variable diameter section 22, for example, 83%, 86%, 88% or 90%.

[0062] This invention pre-divides the coiled structure 24 into three fixed size specifications and allows for the mass production of guide wires corresponding to each size specification of the coiled structure 24. During application, the corresponding guide wire can be selected based on the patient's ventricular size, thus facilitating the procedure. Furthermore, the larger the size specification of these three coiled structures 24, the longer the first variable-diameter segment 22 in the coiled structure 24, ensuring that each coiled structure 24 possesses essentially the same deformation capacity and elastic recovery capability. Optionally, the coiled structure 24 can also be designed in more sizes according to the patient's actual situation, not limited to the three mentioned above. For example, each of the above can be further subdivided, but the larger the size specification, the longer the first variable-diameter segment 22 in the coiled structure 24.

[0063] Furthermore, the taper of the first variable diameter section 22 is 20:10000-30:10000, for example, 20:10000, 25:10000 or 30:10000, etc., the diameter of the large end is 0.55mm-0.58mm, for example, 0.55mm, 0.56mm, 0.57mm or 0.58mm, etc., and the length of the first variable diameter section 22 is 120mm-140mm, for example, 120mm, 130mm or 140mm, etc.

[0064] This combination method can further reduce the compressive force required for the coiled structure 24 to deform under pressure, and the curve recovery rate of the coiled structure 24 can reach more than 97%, further reducing the burden during ventricular contraction, while enhancing the anchoring ability of the distal end of the guide wire.

[0065] The ratio of the length of the first equal-diameter section 21 to the length of the first variable-diameter section 22 is 0.067-0.2, for example, 0.067, 0.08, 0.1, 0.13, 0.16, 0.18 or 0.2, etc.

[0066] By making the length of the first equal diameter section 21 much smaller than the length of the first variable diameter section 22, the first equal diameter section 21 is located entirely in the innermost circle on the coiled structure 24, thereby avoiding the situation where the easily deformable first equal diameter section 21 punctures the heart chamber wall.

[0067] In a specific embodiment, when the first variable diameter section 22 has a length as described in any of the above embodiments, the first constant diameter section 21 has a length of 10-20mm, such as 10mm, 12mm, 15mm, 18mm or 20mm.

[0068] In the above embodiments, the length of the second constant diameter section 23 is preferably 50-100mm, such as 50mm, 60mm, 70mm, 80mm, 90mm or 100mm. By setting the length of the second constant diameter section 23 in this range, a long enough fixed connection structure can be formed between the spring coil 4 and the second constant diameter section 23, and the fixation reliability of the spring coil 4 can be increased. In addition, a large support force can be provided for the crimping structure 24 during the compression and recovery of the crimping structure 24, and the anchoring position of the crimping structure 24 in the ventricle can be ensured. Of course, the length of the second constant diameter section 23 can also be selected to be outside the range of 50-100mm.

[0069] The bare section 3 can only include constant diameter sections, or can include both constant diameter sections and variable diameter sections. In the latter case, the number of constant diameter sections and variable diameter sections is not limited by the present application, but the diameter of the bare section 3 as a whole gradually increases from the distal end to the proximal end, and the constant diameter sections and variable diameter sections are arranged in an alternating manner. In a preferred embodiment, the diameter of the second variable diameter section 31 gradually increases from the distal end to the proximal end. The bare section 3 includes the second variable diameter section 31 and the third constant diameter section 32 arranged in sequence. The third constant diameter section 32 is connected to the covered section 2 through the second variable diameter section 31. The small end of the second variable diameter section 31 has a diameter equal to that of the second constant diameter section 23, and the large end of the second variable diameter section 31 has a diameter equal to that of the third constant diameter section 32.

[0070] Referring to Figure 3 , the diameter of the second variable diameter section 31 varies at different positions. The second variable diameter section 31 can be a variable diameter section with a continuously changing diameter, such as a frustum structure (i.e. the generatrix of the outer wall is a straight line) or a spherical frustum structure (i.e. the generatrix of the outer wall is an arc). The second variable diameter section 31 can also be a variable diameter section with a stepwise changing diameter, such as a plurality of cylindrical sections with different diameters. In this case, it is preferred that the two adjacent cylindrical sections are connected through a conical structure. The diameter of the third constant diameter section 32 is equal at different positions, i.e. the third constant diameter section 32 has a cylindrical structure.

[0071] The distal end of the second variable diameter section 31 is connected to the proximal end of the second constant diameter section 23, and the diameter of the distal end (small end) of the second variable diameter section 31 is equal to the diameter of the second constant diameter section 23, so that the second constant diameter section 23 and the second variable diameter section 31 can be smoothly connected; the proximal end of the second variable diameter section 31 is connected to the distal end of the third constant diameter section 32, and the proximal end (large end) of the second variable diameter section 31 is equal to the diameter of the third constant diameter section 32, so that the second variable diameter section 31 and the third constant diameter section 32 can be smoothly connected, thereby ensuring the structural strength of the junction between the second constant diameter section 23 and the second variable diameter section 31 and the junction between the second variable diameter section 31 and the third constant diameter section 32, and improving the rigidity of the entire guide wire except the covering section, which is beneficial to the torque transmission of the entire guide wire.

[0072] For the core wire 1, from the distal end to the proximal end, the diameter of the core wire 1 only increases or remains unchanged, so that the diameter of the bare section 3 is greater than the diameter of the covering section 2, ensuring that the bare section 3 has sufficient structural strength to meet the requirements of transcatheter aortic valve implantation.

[0073] Preferably, the diameter of the third constant diameter section 32 is 0.762-0.889 mm, and the outer diameter of the spring coil 4 is equal to the diameter of the third constant diameter section 32. The length of the second variable diameter section 31 is 5-100 mm, for example, 5 mm, 8 mm, 12 mm, 15 mm, 20 mm, 50 mm, 70 mm, 90 mm, or 100 mm, etc. The length of the second variable diameter section 31 is relatively small, so that the diameters of the guide wire at most positions are the same, which facilitates the guide wire to pass through the sheath tube.

[0074] For the guide wire, the diameter of the part of the guide wire corresponding to the covering section 2 is the outer diameter of the spring coil 4, the diameters of the bare section 3 at different positions are the diameters of the corresponding parts of the guide wire, and the outer diameter of the spring coil 4 is substantially equal to the diameter of the third constant diameter section 32, that is, only the part of the second variable diameter section 31 in the entire guide wire has a relatively small diameter, and the length of the second variable diameter section 31 is only 5-100 mm, so that the diameters of the guide wire at different positions are substantially equal, thereby facilitating the guide wire to pass through the sheath tube.

[0075] In another embodiment, the bare section 3 has a constant diameter, that is, the diameters of the bare section 3 at different positions are equal. In this embodiment, the diameter of the bare section 3 can be equal to the diameter of the second constant diameter section 23, and more preferably, the diameter of the bare section 3 is greater than the diameter of the second constant diameter section 23 and equal to the outer diameter of the spring coil 4, so that the diameters of the guide wire at different positions are the same.

[0076] For the spring coil 4, preferably, the spring coil 4 has a cylindrical structure, one end of the inner wall of the spring coil 4 is attached to the outer circumferential surface of the second constant diameter section 23, and the other end is connected to the fixing member 5.

[0077] The outer diameter of the spring coil 4 is the same at each location, the inner diameter of the spring coil 4 is the same at each location, the inner diameter of the spring coil 4 can be matched with the outer diameter of the second constant diameter section 23, so that the entire outer surface of the second constant diameter section 23 can be glued or laser welded with the spring coil 4, thereby enhancing the connection strength between the spring coil 4 and the core wire 1. The distal end of the spring coil 4 is connected with the fixing member 5, increasing the contact surface between the spring coil 4 and the fixing member 5, and then the two are glued or laser welded, so that both ends of the spring coil 4 can be reliably fixed, so that the spring coil 4 has a good covering effect on the covering section 2.

[0078] Further, the gap between the two adjacent turns of the spring coil 4 is 0.01-0.04mm, and when the outer peripheral surface of the wire is provided with a PTFE coating, the spring coil is still wound according to the gap, that is, when the coating is provided, the thickness of the coating will also be considered during winding. The gap is, for example, 0.01mm, 0.02mm, 0.03mm or 0.04mm. The spring coil 4 is wound by the wire, and the gap between the two adjacent turns of the wire is 0.01-0.04mm, so that the trend of the spring coil 4 can be easily controlled, thereby facilitating the spring coil 4 to be arranged outside the covering section 2 and to follow the crimping structure 24 to be crimped.

[0079] Preferably, the outer peripheral surface of the spring coil 4 and the outer peripheral surface of the bare section 3 are both provided with a PTFE coating. The PTFE coating can enhance the lubricity of the guide wire, facilitate the guide wire to pass through the sheath, and also prevent the guide wire from injuring the ventricular wall. For the spring coil 4, the PTFE coating can be applied to the outer peripheral surface of the wire before the spring coil 4 is wound.

[0080] Preferably, the material of the core wire 1 and the spring coil 4 is selected from one of 304 stainless steel and nickel-titanium alloy, that is, the material of the core wire 1 can be 304 stainless steel or nickel-titanium alloy, and the material of the spring coil 4 can also be 304 stainless steel and nickel-titanium alloy, and the materials of the two can be the same or different. By using such materials, the guide wire has appropriate hardness and elasticity to meet the needs of the operation.

[0081] The application also relates to an artificial valve delivery system, comprising a sheath and the medical guide wire described above, the medical guide wire is divided into an anchoring section 7 and a guide section 6 along the axial direction thereof, the anchoring section 7 forms a crimping structure 24, the medical guide wire can be inserted into the sheath, and the anchoring section 7 is basically in a strip structure in the sheath.

[0082] When the guide wire is inserted into the sheath, the anchoring section 7 of the guide wire is in a strip structure, so as to facilitate the guide wire to pass through the aorta to reach the ventricle, and then the distal end of the guide wire extends out of the sheath, the sheath no longer limits the distal end of the guide wire, so that the first equal-diameter section 21 and the partial first variable-diameter section 22 connected thereto are restored from the strip structure to the coiled structure 24 under the action of the self-elastic force, so that the anchoring section 7 of the guide wire is coiled and anchored in the ventricle. Moreover, the coiled structure 24 has a compression deformation capacity of 0.4-0.7 N in the first direction, and the recovery rate of the curve after deformation is greater than or equal to 95%, so that, in the process of ventricular contraction, the burden of the ventricle is not increased due to the extrusion of the coiled structure, and in the process of ventricular diastole, the coiled structure 24 can be restored to the original state under the self-elastic recovery capacity, which improves the anchoring capacity of the anchoring section 7 of the guide wire and ensures the smooth performance of the transcatheter aortic valve implantation.

[0083] It should be understood that the above embodiments are only exemplary and not limiting, and those skilled in the art can make various obvious or equivalent modifications or replacements to the above details without departing from the essential principles of the present application, which shall be included in the scope of the claims of the present application.

Claims

1. A medical guide wire for use in a transcatheter intervention, characterized in that The guide wire comprises a core wire, a fixing member and a spring coil, the core wire comprises a covered section and a bare section arranged in sequence from the distal end to the proximal end of the core wire, part of the covered section is in a curled structure; the fixing member is connected to the distal end of the covered section; the spring coil is in a cylindrical structure, is sleeved on the outer periphery of the covered section, and the proximal end of the spring coil is connected to the proximal end of the covered section and the distal end of the spring coil is connected to the fixing member; The covered section comprises a first constant-diameter section, a first variable-diameter section and a second constant-diameter section arranged in sequence from the distal end to the proximal end of the covered section, the first variable-diameter section is a tapered section, the taper of the first variable-diameter section is 20:10000-52:10000, the diameter of the large end is 0.5-0.6mm, and the length of the first variable-diameter section is 100mm-150mm; the diameter of the first constant-diameter section is equal to the diameter of the small end of the first variable-diameter section, and the diameter of the second constant-diameter section is equal to the diameter of the large end, and the proximal end of the second constant-diameter section is connected to the bare section; The curled structure comprises the first constant-diameter section and part of the first variable-diameter section connected to the first constant-diameter section, the length of the part of the first variable-diameter section used to form the curled structure accounts for 70%-90% of the total length of the first variable-diameter section, so that the starting point of the curled structure is located in the first variable-diameter section, different size specifications of the curled structure can be formed by selecting different starting points in the first variable-diameter section using the same size specification of the core wire, the greater the size specification of the curled structure, the greater the proportion of the length of the part of the first variable-diameter section used to form the curled structure accounts for the total length of the first variable-diameter section, and the number of winding turns of the curled structure is not less than 1.5 turns, the outermost turn of the curled structure is formed by the first variable-diameter section, and the curled structure is located in the same plane in a natural state and can be compressed or unfolded into a strip structure under the action of an external force.

2. The medical guide wire according to claim 1, wherein when the size specification of the curled structure is that the size in the first direction is 20mm-32mm and the size in the second direction is 25mm-37mm, the length of the first variable-diameter section in the curled structure accounts for 70%-78% of the total length of the first variable-diameter section; when the size specification of the curled structure is that the size in the first direction is 30mm-43mm and the size in the second direction is 35mm-48mm, the length of the first variable-diameter section in the curled structure accounts for 76%-85% of the total length of the first variable-diameter section; when the size specification of the curled structure is that the size in the first direction is 40mm-50mm and the size in the second direction is 46mm-55mm, the length of the first variable-diameter section in the curled structure accounts for 83%-90% of the total length of the first variable-diameter section; wherein the normal direction of the curled structure at the starting point thereof is the first direction, and the direction perpendicular to the first direction is the second direction.

3. The medical guide wire according to claim 1, wherein The taper of the first variable-diameter section is 20:10000-30:10000, the diameter of the large end is 0.55mm-0.58mm, and the length of the first variable-diameter section is 120mm-140mm.

4. The medical guide wire according to claim 1, wherein The diameter of the small end of the first variable diameter section is 0.08-0.2mm, and the ratio of the length of the first constant diameter section to the length of the first variable diameter section is 0.067-0.

2.

5. The medical guide wire according to claim 1, wherein The length of the second constant diameter section is 50-100mm.

6. The medical guide wire according to any one of claims 1 to 5, characterized by In the direction from the distal end to the proximal end, the bare section comprises a second variable diameter section and a third constant diameter section arranged in sequence, and the diameter of the second variable diameter section gradually increases; the third constant diameter section is connected with the covered section through the second variable diameter section, the small end of the second variable diameter section has the same diameter as the second constant diameter section, and the large end of the second variable diameter section has the same diameter as the third constant diameter section.

7. The medical guide wire according to claim 6, characterized by The diameter of the third constant diameter section is 0.762-0.889mm, and the outer diameter of the spring coil is equal to the diameter of the third constant diameter section; the length of the second variable diameter section is 5-100mm.

8. The medical guide wire according to any one of claims 1 to 5, characterized by The bare section is a constant diameter section.

9. The medical guide wire according to any one of claims 1 to 8, characterized by The spring coil is a cylindrical structure, one end of the inner wall of which is attached to the outer peripheral surface of the second constant diameter section, and the other end is connected with the fixing member through insertion.

10. The medical guide wire according to any one of claims 1 to 8, characterized by The gap between two adjacent turns of the spring coil is 0.01mm-0.04mm.

11. The medical guide wire according to any one of claims 1 to 10, characterized in that, The outer periphery of the spring coil and the outer peripheral surface of the bare section are both provided with a PTFE coating.

12. The medical guide wire according to any one of claims 1 to 11, characterized by The material of the core wire and the spring coil is selected from 304 stainless steel and nickel-titanium alloy.

13. A prosthetic valve delivery system, comprising: The medical guide wire comprises a sheath and the medical guide wire according to any one of claims 1-12, the medical guide wire can be inserted into the sheath, and the coiled structure is basically in a strip structure in the sheath.

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